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authorRalf Baechle <ralf@linux-mips.org>2006-04-05 09:45:45 +0100
committerRalf Baechle <ralf@linux-mips.org>2006-04-19 04:14:28 +0200
commit41c594ab65fc89573af296d192aa5235d09717ab (patch)
tree562462512a320f386bdf49eabfbb26bb3ee761fa /arch/mips/kernel
parent2600990e640e3bef29ed89d565864cf16ee83833 (diff)
downloadop-kernel-dev-41c594ab65fc89573af296d192aa5235d09717ab.zip
op-kernel-dev-41c594ab65fc89573af296d192aa5235d09717ab.tar.gz
[MIPS] MT: Improved multithreading support.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel')
-rw-r--r--arch/mips/kernel/Makefile4
-rw-r--r--arch/mips/kernel/asm-offsets.c3
-rw-r--r--arch/mips/kernel/entry.S34
-rw-r--r--arch/mips/kernel/gdb-low.S24
-rw-r--r--arch/mips/kernel/gdb-stub.c61
-rw-r--r--arch/mips/kernel/genex.S29
-rw-r--r--arch/mips/kernel/head.S57
-rw-r--r--arch/mips/kernel/i8259.c4
-rw-r--r--arch/mips/kernel/irq-msc01.c9
-rw-r--r--arch/mips/kernel/irq.c13
-rw-r--r--arch/mips/kernel/mips-mt.c449
-rw-r--r--arch/mips/kernel/process.c10
-rw-r--r--arch/mips/kernel/ptrace.c14
-rw-r--r--arch/mips/kernel/ptrace32.c14
-rw-r--r--arch/mips/kernel/r4k_switch.S34
-rw-r--r--arch/mips/kernel/smp-mt.c (renamed from arch/mips/kernel/smp_mt.c)33
-rw-r--r--arch/mips/kernel/smp.c10
-rw-r--r--arch/mips/kernel/smtc-asm.S130
-rw-r--r--arch/mips/kernel/smtc-proc.c93
-rw-r--r--arch/mips/kernel/smtc.c1322
-rw-r--r--arch/mips/kernel/time.c3
-rw-r--r--arch/mips/kernel/traps.c124
-rw-r--r--arch/mips/kernel/vmlinux.lds.S2
23 files changed, 2447 insertions, 29 deletions
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 9ec01de..34e8a25 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -34,7 +34,9 @@ obj-$(CONFIG_CPU_R6000) += r6000_fpu.o r4k_switch.o
obj-$(CONFIG_SMP) += smp.o
-obj-$(CONFIG_MIPS_MT_SMP) += smp_mt.o
+obj-$(CONFIG_MIPS_MT) += mips-mt.o
+obj-$(CONFIG_MIPS_MT_SMTC) += smtc.o smtc-asm.o smtc-proc.o
+obj-$(CONFIG_MIPS_MT_SMP) += smp-mt.o
obj-$(CONFIG_MIPS_APSP_KSPD) += kspd.o
obj-$(CONFIG_MIPS_VPE_LOADER) += vpe.o
diff --git a/arch/mips/kernel/asm-offsets.c b/arch/mips/kernel/asm-offsets.c
index ca6b03c..92b28b6 100644
--- a/arch/mips/kernel/asm-offsets.c
+++ b/arch/mips/kernel/asm-offsets.c
@@ -69,6 +69,9 @@ void output_ptreg_defines(void)
offset("#define PT_BVADDR ", struct pt_regs, cp0_badvaddr);
offset("#define PT_STATUS ", struct pt_regs, cp0_status);
offset("#define PT_CAUSE ", struct pt_regs, cp0_cause);
+#ifdef CONFIG_MIPS_MT_SMTC
+ offset("#define PT_TCSTATUS ", struct pt_regs, cp0_tcstatus);
+#endif /* CONFIG_MIPS_MT_SMTC */
size("#define PT_SIZE ", struct pt_regs);
linefeed;
}
diff --git a/arch/mips/kernel/entry.S b/arch/mips/kernel/entry.S
index b1939a4..d101d2f 100644
--- a/arch/mips/kernel/entry.S
+++ b/arch/mips/kernel/entry.S
@@ -17,6 +17,9 @@
#include <asm/isadep.h>
#include <asm/thread_info.h>
#include <asm/war.h>
+#ifdef CONFIG_MIPS_MT_SMTC
+#include <asm/mipsmtregs.h>
+#endif
#ifdef CONFIG_PREEMPT
.macro preempt_stop
@@ -75,6 +78,37 @@ FEXPORT(syscall_exit)
bnez t0, syscall_exit_work
FEXPORT(restore_all) # restore full frame
+#ifdef CONFIG_MIPS_MT_SMTC
+/* Detect and execute deferred IPI "interrupts" */
+ move a0,sp
+ jal deferred_smtc_ipi
+/* Re-arm any temporarily masked interrupts not explicitly "acked" */
+ mfc0 v0, CP0_TCSTATUS
+ ori v1, v0, TCSTATUS_IXMT
+ mtc0 v1, CP0_TCSTATUS
+ andi v0, TCSTATUS_IXMT
+ ehb
+ mfc0 t0, CP0_TCCONTEXT
+ DMT 9 # dmt t1
+ jal mips_ihb
+ mfc0 t2, CP0_STATUS
+ andi t3, t0, 0xff00
+ or t2, t2, t3
+ mtc0 t2, CP0_STATUS
+ ehb
+ andi t1, t1, VPECONTROL_TE
+ beqz t1, 1f
+ EMT
+1:
+ mfc0 v1, CP0_TCSTATUS
+ /* We set IXMT above, XOR should cler it here */
+ xori v1, v1, TCSTATUS_IXMT
+ or v1, v0, v1
+ mtc0 v1, CP0_TCSTATUS
+ ehb
+ xor t0, t0, t3
+ mtc0 t0, CP0_TCCONTEXT
+#endif /* CONFIG_MIPS_MT_SMTC */
.set noat
RESTORE_TEMP
RESTORE_AT
diff --git a/arch/mips/kernel/gdb-low.S b/arch/mips/kernel/gdb-low.S
index 235ad9f..10f28fb 100644
--- a/arch/mips/kernel/gdb-low.S
+++ b/arch/mips/kernel/gdb-low.S
@@ -283,11 +283,33 @@
*/
3:
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* Read-modify write of Status must be atomic */
+ mfc0 t2, CP0_TCSTATUS
+ ori t1, t2, TCSTATUS_IXMT
+ mtc0 t1, CP0_TCSTATUS
+ andi t2, t2, TCSTATUS_IXMT
+ ehb
+ DMT 9 # dmt t1
+ jal mips_ihb
+ nop
+#endif /* CONFIG_MIPS_MT_SMTC */
mfc0 t0, CP0_STATUS
ori t0, 0x1f
xori t0, 0x1f
mtc0 t0, CP0_STATUS
-
+#ifdef CONFIG_MIPS_MT_SMTC
+ andi t1, t1, VPECONTROL_TE
+ beqz t1, 9f
+ nop
+ EMT # emt
+9:
+ mfc0 t1, CP0_TCSTATUS
+ xori t1, t1, TCSTATUS_IXMT
+ or t1, t1, t2
+ mtc0 t1, CP0_TCSTATUS
+ ehb
+#endif /* CONFIG_MIPS_MT_SMTC */
LONG_L v0, GDB_FR_STATUS(sp)
LONG_L v1, GDB_FR_EPC(sp)
mtc0 v0, CP0_STATUS
diff --git a/arch/mips/kernel/gdb-stub.c b/arch/mips/kernel/gdb-stub.c
index d4f88e0..6ecbdc1 100644
--- a/arch/mips/kernel/gdb-stub.c
+++ b/arch/mips/kernel/gdb-stub.c
@@ -140,6 +140,7 @@
#include <asm/system.h>
#include <asm/gdb-stub.h>
#include <asm/inst.h>
+#include <asm/smp.h>
/*
* external low-level support routines
@@ -669,6 +670,64 @@ static void kgdb_wait(void *arg)
local_irq_restore(flags);
}
+/*
+ * GDB stub needs to call kgdb_wait on all processor with interrupts
+ * disabled, so it uses it's own special variant.
+ */
+static int kgdb_smp_call_kgdb_wait(void)
+{
+#ifdef CONFIG_SMP
+ struct call_data_struct data;
+ int i, cpus = num_online_cpus() - 1;
+ int cpu = smp_processor_id();
+
+ /*
+ * Can die spectacularly if this CPU isn't yet marked online
+ */
+ BUG_ON(!cpu_online(cpu));
+
+ if (!cpus)
+ return 0;
+
+ if (spin_is_locked(&smp_call_lock)) {
+ /*
+ * Some other processor is trying to make us do something
+ * but we're not going to respond... give up
+ */
+ return -1;
+ }
+
+ /*
+ * We will continue here, accepting the fact that
+ * the kernel may deadlock if another CPU attempts
+ * to call smp_call_function now...
+ */
+
+ data.func = kgdb_wait;
+ data.info = NULL;
+ atomic_set(&data.started, 0);
+ data.wait = 0;
+
+ spin_lock(&smp_call_lock);
+ call_data = &data;
+ mb();
+
+ /* Send a message to all other CPUs and wait for them to respond */
+ for (i = 0; i < NR_CPUS; i++)
+ if (cpu_online(i) && i != cpu)
+ core_send_ipi(i, SMP_CALL_FUNCTION);
+
+ /* Wait for response */
+ /* FIXME: lock-up detection, backtrace on lock-up */
+ while (atomic_read(&data.started) != cpus)
+ barrier();
+
+ call_data = NULL;
+ spin_unlock(&smp_call_lock);
+#endif
+
+ return 0;
+}
/*
* This function does all command processing for interfacing to gdb. It
@@ -718,7 +777,7 @@ void handle_exception (struct gdb_regs *regs)
/*
* force other cpus to enter kgdb
*/
- smp_call_function(kgdb_wait, NULL, 0, 0);
+ kgdb_smp_call_kgdb_wait();
/*
* If we're in breakpoint() increment the PC
diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
index 04418b6..ff7af36 100644
--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -12,6 +12,7 @@
#include <linux/init.h>
#include <asm/asm.h>
+#include <asm/asmmacro.h>
#include <asm/cacheops.h>
#include <asm/regdef.h>
#include <asm/fpregdef.h>
@@ -171,6 +172,15 @@ NESTED(except_vec_vi, 0, sp)
SAVE_AT
.set push
.set noreorder
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * To keep from blindly blocking *all* interrupts
+ * during service by SMTC kernel, we also want to
+ * pass the IM value to be cleared.
+ */
+EXPORT(except_vec_vi_mori)
+ ori a0, $0, 0
+#endif /* CONFIG_MIPS_MT_SMTC */
EXPORT(except_vec_vi_lui)
lui v0, 0 /* Patched */
j except_vec_vi_handler
@@ -187,6 +197,25 @@ EXPORT(except_vec_vi_end)
NESTED(except_vec_vi_handler, 0, sp)
SAVE_TEMP
SAVE_STATIC
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * SMTC has an interesting problem that interrupts are level-triggered,
+ * and the CLI macro will clear EXL, potentially causing a duplicate
+ * interrupt service invocation. So we need to clear the associated
+ * IM bit of Status prior to doing CLI, and restore it after the
+ * service routine has been invoked - we must assume that the
+ * service routine will have cleared the state, and any active
+ * level represents a new or otherwised unserviced event...
+ */
+ mfc0 t1, CP0_STATUS
+ and t0, a0, t1
+ mfc0 t2, CP0_TCCONTEXT
+ or t0, t0, t2
+ mtc0 t0, CP0_TCCONTEXT
+ xor t1, t1, t0
+ mtc0 t1, CP0_STATUS
+ ehb
+#endif /* CONFIG_MIPS_MT_SMTC */
CLI
move a0, sp
jalr v0
diff --git a/arch/mips/kernel/head.S b/arch/mips/kernel/head.S
index 2e9122a..bdf6f6e 100644
--- a/arch/mips/kernel/head.S
+++ b/arch/mips/kernel/head.S
@@ -18,6 +18,7 @@
#include <linux/threads.h>
#include <asm/asm.h>
+#include <asm/asmmacro.h>
#include <asm/regdef.h>
#include <asm/page.h>
#include <asm/mipsregs.h>
@@ -82,12 +83,33 @@
*/
.macro setup_c0_status set clr
.set push
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * For SMTC, we need to set privilege and disable interrupts only for
+ * the current TC, using the TCStatus register.
+ */
+ mfc0 t0, CP0_TCSTATUS
+ /* Fortunately CU 0 is in the same place in both registers */
+ /* Set TCU0, TMX, TKSU (for later inversion) and IXMT */
+ li t1, ST0_CU0 | 0x08001c00
+ or t0, t1
+ /* Clear TKSU, leave IXMT */
+ xori t0, 0x00001800
+ mtc0 t0, CP0_TCSTATUS
+ ehb
+ /* We need to leave the global IE bit set, but clear EXL...*/
+ mfc0 t0, CP0_STATUS
+ or t0, ST0_CU0 | ST0_EXL | ST0_ERL | \set | \clr
+ xor t0, ST0_EXL | ST0_ERL | \clr
+ mtc0 t0, CP0_STATUS
+#else
mfc0 t0, CP0_STATUS
or t0, ST0_CU0|\set|0x1f|\clr
xor t0, 0x1f|\clr
mtc0 t0, CP0_STATUS
.set noreorder
sll zero,3 # ehb
+#endif
.set pop
.endm
@@ -134,6 +156,24 @@ NESTED(kernel_entry, 16, sp) # kernel entry point
ARC64_TWIDDLE_PC
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * In SMTC kernel, "CLI" is thread-specific, in TCStatus.
+ * We still need to enable interrupts globally in Status,
+ * and clear EXL/ERL.
+ *
+ * TCContext is used to track interrupt levels under
+ * service in SMTC kernel. Clear for boot TC before
+ * allowing any interrupts.
+ */
+ mtc0 zero, CP0_TCCONTEXT
+
+ mfc0 t0, CP0_STATUS
+ ori t0, t0, 0xff1f
+ xori t0, t0, 0x001e
+ mtc0 t0, CP0_STATUS
+#endif /* CONFIG_MIPS_MT_SMTC */
+
PTR_LA t0, __bss_start # clear .bss
LONG_S zero, (t0)
PTR_LA t1, __bss_stop - LONGSIZE
@@ -166,8 +206,25 @@ NESTED(kernel_entry, 16, sp) # kernel entry point
* function after setting up the stack and gp registers.
*/
NESTED(smp_bootstrap, 16, sp)
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * Read-modify-writes of Status must be atomic, and this
+ * is one case where CLI is invoked without EXL being
+ * necessarily set. The CLI and setup_c0_status will
+ * in fact be redundant for all but the first TC of
+ * each VPE being booted.
+ */
+ DMT 10 # dmt t2 /* t0, t1 are used by CLI and setup_c0_status() */
+ jal mips_ihb
+#endif /* CONFIG_MIPS_MT_SMTC */
setup_c0_status_sec
smp_slave_setup
+#ifdef CONFIG_MIPS_MT_SMTC
+ andi t2, t2, VPECONTROL_TE
+ beqz t2, 2f
+ EMT # emt
+2:
+#endif /* CONFIG_MIPS_MT_SMTC */
j start_secondary
END(smp_bootstrap)
#endif /* CONFIG_SMP */
diff --git a/arch/mips/kernel/i8259.c b/arch/mips/kernel/i8259.c
index b974ac9..2125ba5 100644
--- a/arch/mips/kernel/i8259.c
+++ b/arch/mips/kernel/i8259.c
@@ -187,6 +187,10 @@ handle_real_irq:
outb(cached_21,0x21);
outb(0x60+irq,0x20); /* 'Specific EOI' to master */
}
+#ifdef CONFIG_MIPS_MT_SMTC
+ if (irq_hwmask[irq] & ST0_IM)
+ set_c0_status(irq_hwmask[irq] & ST0_IM);
+#endif /* CONFIG_MIPS_MT_SMTC */
spin_unlock_irqrestore(&i8259A_lock, flags);
return;
diff --git a/arch/mips/kernel/irq-msc01.c b/arch/mips/kernel/irq-msc01.c
index 3f653c7..97ebdc7 100644
--- a/arch/mips/kernel/irq-msc01.c
+++ b/arch/mips/kernel/irq-msc01.c
@@ -76,6 +76,11 @@ static void level_mask_and_ack_msc_irq(unsigned int irq)
mask_msc_irq(irq);
if (!cpu_has_veic)
MSCIC_WRITE(MSC01_IC_EOI, 0);
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* This actually needs to be a call into platform code */
+ if (irq_hwmask[irq] & ST0_IM)
+ set_c0_status(irq_hwmask[irq] & ST0_IM);
+#endif /* CONFIG_MIPS_MT_SMTC */
}
/*
@@ -92,6 +97,10 @@ static void edge_mask_and_ack_msc_irq(unsigned int irq)
MSCIC_WRITE(MSC01_IC_SUP+irq*8, r | ~MSC01_IC_SUP_EDGE_BIT);
MSCIC_WRITE(MSC01_IC_SUP+irq*8, r);
}
+#ifdef CONFIG_MIPS_MT_SMTC
+ if (irq_hwmask[irq] & ST0_IM)
+ set_c0_status(irq_hwmask[irq] & ST0_IM);
+#endif /* CONFIG_MIPS_MT_SMTC */
}
/*
diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index e0efc4f..3dce742 100644
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -38,6 +38,15 @@ void ack_bad_irq(unsigned int irq)
atomic_t irq_err_count;
+#ifdef CONFIG_MIPS_MT_SMTC
+/*
+ * SMTC Kernel needs to manipulate low-level CPU interrupt mask
+ * in do_IRQ. These are passed in setup_irq_smtc() and stored
+ * in this table.
+ */
+unsigned long irq_hwmask[NR_IRQS];
+#endif /* CONFIG_MIPS_MT_SMTC */
+
#undef do_IRQ
/*
@@ -49,6 +58,7 @@ asmlinkage unsigned int do_IRQ(unsigned int irq, struct pt_regs *regs)
{
irq_enter();
+ __DO_IRQ_SMTC_HOOK();
__do_IRQ(irq, regs);
irq_exit();
@@ -129,6 +139,9 @@ void __init init_IRQ(void)
irq_desc[i].depth = 1;
irq_desc[i].handler = &no_irq_type;
spin_lock_init(&irq_desc[i].lock);
+#ifdef CONFIG_MIPS_MT_SMTC
+ irq_hwmask[i] = 0;
+#endif /* CONFIG_MIPS_MT_SMTC */
}
arch_init_irq();
diff --git a/arch/mips/kernel/mips-mt.c b/arch/mips/kernel/mips-mt.c
new file mode 100644
index 0000000..02237a6
--- /dev/null
+++ b/arch/mips/kernel/mips-mt.c
@@ -0,0 +1,449 @@
+/*
+ * General MIPS MT support routines, usable in AP/SP, SMVP, or SMTC kernels
+ * Copyright (C) 2005 Mips Technologies, Inc
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+
+#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <asm/hardirq.h>
+#include <asm/mmu_context.h>
+#include <asm/smp.h>
+#include <asm/mipsmtregs.h>
+#include <asm/r4kcache.h>
+#include <asm/cacheflush.h>
+
+/*
+ * CPU mask used to set process affinity for MT VPEs/TCs with FPUs
+ */
+
+cpumask_t mt_fpu_cpumask;
+
+#ifdef CONFIG_MIPS_MT_FPAFF
+
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <asm/uaccess.h>
+
+unsigned long mt_fpemul_threshold = 0;
+
+/*
+ * Replacement functions for the sys_sched_setaffinity() and
+ * sys_sched_getaffinity() system calls, so that we can integrate
+ * FPU affinity with the user's requested processor affinity.
+ * This code is 98% identical with the sys_sched_setaffinity()
+ * and sys_sched_getaffinity() system calls, and should be
+ * updated when kernel/sched.c changes.
+ */
+
+/*
+ * find_process_by_pid - find a process with a matching PID value.
+ * used in sys_sched_set/getaffinity() in kernel/sched.c, so
+ * cloned here.
+ */
+static inline task_t *find_process_by_pid(pid_t pid)
+{
+ return pid ? find_task_by_pid(pid) : current;
+}
+
+
+/*
+ * mipsmt_sys_sched_setaffinity - set the cpu affinity of a process
+ */
+asmlinkage long mipsmt_sys_sched_setaffinity(pid_t pid, unsigned int len,
+ unsigned long __user *user_mask_ptr)
+{
+ cpumask_t new_mask;
+ cpumask_t effective_mask;
+ int retval;
+ task_t *p;
+
+ if (len < sizeof(new_mask))
+ return -EINVAL;
+
+ if (copy_from_user(&new_mask, user_mask_ptr, sizeof(new_mask)))
+ return -EFAULT;
+
+ lock_cpu_hotplug();
+ read_lock(&tasklist_lock);
+
+ p = find_process_by_pid(pid);
+ if (!p) {
+ read_unlock(&tasklist_lock);
+ unlock_cpu_hotplug();
+ return -ESRCH;
+ }
+
+ /*
+ * It is not safe to call set_cpus_allowed with the
+ * tasklist_lock held. We will bump the task_struct's
+ * usage count and drop tasklist_lock before invoking
+ * set_cpus_allowed.
+ */
+ get_task_struct(p);
+
+ retval = -EPERM;
+ if ((current->euid != p->euid) && (current->euid != p->uid) &&
+ !capable(CAP_SYS_NICE)) {
+ read_unlock(&tasklist_lock);
+ goto out_unlock;
+ }
+
+ /* Record new user-specified CPU set for future reference */
+ p->thread.user_cpus_allowed = new_mask;
+
+ /* Unlock the task list */
+ read_unlock(&tasklist_lock);
+
+ /* Compute new global allowed CPU set if necessary */
+ if( (p->thread.mflags & MF_FPUBOUND)
+ && cpus_intersects(new_mask, mt_fpu_cpumask)) {
+ cpus_and(effective_mask, new_mask, mt_fpu_cpumask);
+ retval = set_cpus_allowed(p, effective_mask);
+ } else {
+ p->thread.mflags &= ~MF_FPUBOUND;
+ retval = set_cpus_allowed(p, new_mask);
+ }
+
+
+out_unlock:
+ put_task_struct(p);
+ unlock_cpu_hotplug();
+ return retval;
+}
+
+/*
+ * mipsmt_sys_sched_getaffinity - get the cpu affinity of a process
+ */
+asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len,
+ unsigned long __user *user_mask_ptr)
+{
+ unsigned int real_len;
+ cpumask_t mask;
+ int retval;
+ task_t *p;
+
+ real_len = sizeof(mask);
+ if (len < real_len)
+ return -EINVAL;
+
+ lock_cpu_hotplug();
+ read_lock(&tasklist_lock);
+
+ retval = -ESRCH;
+ p = find_process_by_pid(pid);
+ if (!p)
+ goto out_unlock;
+
+ retval = 0;
+
+ cpus_and(mask, p->thread.user_cpus_allowed, cpu_possible_map);
+
+out_unlock:
+ read_unlock(&tasklist_lock);
+ unlock_cpu_hotplug();
+ if (retval)
+ return retval;
+ if (copy_to_user(user_mask_ptr, &mask, real_len))
+ return -EFAULT;
+ return real_len;
+}
+
+#endif /* CONFIG_MIPS_MT_FPAFF */
+
+/*
+ * Dump new MIPS MT state for the core. Does not leave TCs halted.
+ * Takes an argument which taken to be a pre-call MVPControl value.
+ */
+
+void mips_mt_regdump(unsigned long mvpctl)
+{
+ unsigned long flags;
+ unsigned long vpflags;
+ unsigned long mvpconf0;
+ int nvpe;
+ int ntc;
+ int i;
+ int tc;
+ unsigned long haltval;
+ unsigned long tcstatval;
+#ifdef CONFIG_MIPS_MT_SMTC
+ void smtc_soft_dump(void);
+#endif /* CONFIG_MIPT_MT_SMTC */
+
+ local_irq_save(flags);
+ vpflags = dvpe();
+ printk("=== MIPS MT State Dump ===\n");
+ printk("-- Global State --\n");
+ printk(" MVPControl Passed: %08lx\n", mvpctl);
+ printk(" MVPControl Read: %08lx\n", vpflags);
+ printk(" MVPConf0 : %08lx\n", (mvpconf0 = read_c0_mvpconf0()));
+ nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
+ ntc = ((mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
+ printk("-- per-VPE State --\n");
+ for(i = 0; i < nvpe; i++) {
+ for(tc = 0; tc < ntc; tc++) {
+ settc(tc);
+ if((read_tc_c0_tcbind() & TCBIND_CURVPE) == i) {
+ printk(" VPE %d\n", i);
+ printk(" VPEControl : %08lx\n", read_vpe_c0_vpecontrol());
+ printk(" VPEConf0 : %08lx\n", read_vpe_c0_vpeconf0());
+ printk(" VPE%d.Status : %08lx\n",
+ i, read_vpe_c0_status());
+ printk(" VPE%d.EPC : %08lx\n", i, read_vpe_c0_epc());
+ printk(" VPE%d.Cause : %08lx\n", i, read_vpe_c0_cause());
+ printk(" VPE%d.Config7 : %08lx\n",
+ i, read_vpe_c0_config7());
+ break; /* Next VPE */
+ }
+ }
+ }
+ printk("-- per-TC State --\n");
+ for(tc = 0; tc < ntc; tc++) {
+ settc(tc);
+ if(read_tc_c0_tcbind() == read_c0_tcbind()) {
+ /* Are we dumping ourself? */
+ haltval = 0; /* Then we're not halted, and mustn't be */
+ tcstatval = flags; /* And pre-dump TCStatus is flags */
+ printk(" TC %d (current TC with VPE EPC above)\n", tc);
+ } else {
+ haltval = read_tc_c0_tchalt();
+ write_tc_c0_tchalt(1);
+ tcstatval = read_tc_c0_tcstatus();
+ printk(" TC %d\n", tc);
+ }
+ printk(" TCStatus : %08lx\n", tcstatval);
+ printk(" TCBind : %08lx\n", read_tc_c0_tcbind());
+ printk(" TCRestart : %08lx\n", read_tc_c0_tcrestart());
+ printk(" TCHalt : %08lx\n", haltval);
+ printk(" TCContext : %08lx\n", read_tc_c0_tccontext());
+ if (!haltval)
+ write_tc_c0_tchalt(0);
+ }
+#ifdef CONFIG_MIPS_MT_SMTC
+ smtc_soft_dump();
+#endif /* CONFIG_MIPT_MT_SMTC */
+ printk("===========================\n");
+ evpe(vpflags);
+ local_irq_restore(flags);
+}
+
+static int mt_opt_norps = 0;
+static int mt_opt_rpsctl = -1;
+static int mt_opt_nblsu = -1;
+static int mt_opt_forceconfig7 = 0;
+static int mt_opt_config7 = -1;
+
+static int __init rps_disable(char *s)
+{
+ mt_opt_norps = 1;
+ return 1;
+}
+__setup("norps", rps_disable);
+
+static int __init rpsctl_set(char *str)
+{
+ get_option(&str, &mt_opt_rpsctl);
+ return 1;
+}
+__setup("rpsctl=", rpsctl_set);
+
+static int __init nblsu_set(char *str)
+{
+ get_option(&str, &mt_opt_nblsu);
+ return 1;
+}
+__setup("nblsu=", nblsu_set);
+
+static int __init config7_set(char *str)
+{
+ get_option(&str, &mt_opt_config7);
+ mt_opt_forceconfig7 = 1;
+ return 1;
+}
+__setup("config7=", config7_set);
+
+/* Experimental cache flush control parameters that should go away some day */
+int mt_protiflush = 0;
+int mt_protdflush = 0;
+int mt_n_iflushes = 1;
+int mt_n_dflushes = 1;
+
+static int __init set_protiflush(char *s)
+{
+ mt_protiflush = 1;
+ return 1;
+}
+__setup("protiflush", set_protiflush);
+
+static int __init set_protdflush(char *s)
+{
+ mt_protdflush = 1;
+ return 1;
+}
+__setup("protdflush", set_protdflush);
+
+static int __init niflush(char *s)
+{
+ get_option(&s, &mt_n_iflushes);
+ return 1;
+}
+__setup("niflush=", niflush);
+
+static int __init ndflush(char *s)
+{
+ get_option(&s, &mt_n_dflushes);
+ return 1;
+}
+__setup("ndflush=", ndflush);
+#ifdef CONFIG_MIPS_MT_FPAFF
+static int fpaff_threshold = -1;
+
+static int __init fpaff_thresh(char *str)
+{
+ get_option(&str, &fpaff_threshold);
+ return 1;
+}
+
+__setup("fpaff=", fpaff_thresh);
+#endif /* CONFIG_MIPS_MT_FPAFF */
+
+static unsigned int itc_base = 0;
+
+static int __init set_itc_base(char *str)
+{
+ get_option(&str, &itc_base);
+ return 1;
+}
+
+__setup("itcbase=", set_itc_base);
+
+void mips_mt_set_cpuoptions(void)
+{
+ unsigned int oconfig7 = read_c0_config7();
+ unsigned int nconfig7 = oconfig7;
+
+ if (mt_opt_norps) {
+ printk("\"norps\" option deprectated: use \"rpsctl=\"\n");
+ }
+ if (mt_opt_rpsctl >= 0) {
+ printk("34K return prediction stack override set to %d.\n",
+ mt_opt_rpsctl);
+ if (mt_opt_rpsctl)
+ nconfig7 |= (1 << 2);
+ else
+ nconfig7 &= ~(1 << 2);
+ }
+ if (mt_opt_nblsu >= 0) {
+ printk("34K ALU/LSU sync override set to %d.\n", mt_opt_nblsu);
+ if (mt_opt_nblsu)
+ nconfig7 |= (1 << 5);
+ else
+ nconfig7 &= ~(1 << 5);
+ }
+ if (mt_opt_forceconfig7) {
+ printk("CP0.Config7 forced to 0x%08x.\n", mt_opt_config7);
+ nconfig7 = mt_opt_config7;
+ }
+ if (oconfig7 != nconfig7) {
+ __asm__ __volatile("sync");
+ write_c0_config7(nconfig7);
+ ehb ();
+ printk("Config7: 0x%08x\n", read_c0_config7());
+ }
+
+ /* Report Cache management debug options */
+ if (mt_protiflush)
+ printk("I-cache flushes single-threaded\n");
+ if (mt_protdflush)
+ printk("D-cache flushes single-threaded\n");
+ if (mt_n_iflushes != 1)
+ printk("I-Cache Flushes Repeated %d times\n", mt_n_iflushes);
+ if (mt_n_dflushes != 1)
+ printk("D-Cache Flushes Repeated %d times\n", mt_n_dflushes);
+
+#ifdef CONFIG_MIPS_MT_FPAFF
+ /* FPU Use Factor empirically derived from experiments on 34K */
+#define FPUSEFACTOR 333
+
+ if (fpaff_threshold >= 0) {
+ mt_fpemul_threshold = fpaff_threshold;
+ } else {
+ mt_fpemul_threshold =
+ (FPUSEFACTOR * (loops_per_jiffy/(500000/HZ))) / HZ;
+ }
+ printk("FPU Affinity set after %ld emulations\n",
+ mt_fpemul_threshold);
+#endif /* CONFIG_MIPS_MT_FPAFF */
+
+ if (itc_base != 0) {
+ /*
+ * Configure ITC mapping. This code is very
+ * specific to the 34K core family, which uses
+ * a special mode bit ("ITC") in the ErrCtl
+ * register to enable access to ITC control
+ * registers via cache "tag" operations.
+ */
+ unsigned long ectlval;
+ unsigned long itcblkgrn;
+
+ /* ErrCtl register is known as "ecc" to Linux */
+ ectlval = read_c0_ecc();
+ write_c0_ecc(ectlval | (0x1 << 26));
+ ehb();
+#define INDEX_0 (0x80000000)
+#define INDEX_8 (0x80000008)
+ /* Read "cache tag" for Dcache pseudo-index 8 */
+ cache_op(Index_Load_Tag_D, INDEX_8);
+ ehb();
+ itcblkgrn = read_c0_dtaglo();
+ itcblkgrn &= 0xfffe0000;
+ /* Set for 128 byte pitch of ITC cells */
+ itcblkgrn |= 0x00000c00;
+ /* Stage in Tag register */
+ write_c0_dtaglo(itcblkgrn);
+ ehb();
+ /* Write out to ITU with CACHE op */
+ cache_op(Index_Store_Tag_D, INDEX_8);
+ /* Now set base address, and turn ITC on with 0x1 bit */
+ write_c0_dtaglo((itc_base & 0xfffffc00) | 0x1 );
+ ehb();
+ /* Write out to ITU with CACHE op */
+ cache_op(Index_Store_Tag_D, INDEX_0);
+ write_c0_ecc(ectlval);
+ ehb();
+ printk("Mapped %ld ITC cells starting at 0x%08x\n",
+ ((itcblkgrn & 0x7fe00000) >> 20), itc_base);
+ }
+}
+
+/*
+ * Function to protect cache flushes from concurrent execution
+ * depends on MP software model chosen.
+ */
+
+void mt_cflush_lockdown(void)
+{
+#ifdef CONFIG_MIPS_MT_SMTC
+ void smtc_cflush_lockdown(void);
+
+ smtc_cflush_lockdown();
+#endif /* CONFIG_MIPS_MT_SMTC */
+ /* FILL IN VSMP and AP/SP VERSIONS HERE */
+}
+
+void mt_cflush_release(void)
+{
+#ifdef CONFIG_MIPS_MT_SMTC
+ void smtc_cflush_release(void);
+
+ smtc_cflush_release();
+#endif /* CONFIG_MIPS_MT_SMTC */
+ /* FILL IN VSMP and AP/SP VERSIONS HERE */
+}
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index c66db5e..8b393df 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -41,6 +41,10 @@
#include <asm/elf.h>
#include <asm/isadep.h>
#include <asm/inst.h>
+#ifdef CONFIG_MIPS_MT_SMTC
+#include <asm/mipsmtregs.h>
+extern void smtc_idle_loop_hook(void);
+#endif /* CONFIG_MIPS_MT_SMTC */
/*
* The idle thread. There's no useful work to be done, so just try to conserve
@@ -51,9 +55,13 @@ ATTRIB_NORET void cpu_idle(void)
{
/* endless idle loop with no priority at all */
while (1) {
- while (!need_resched())
+ while (!need_resched()) {
+#ifdef CONFIG_MIPS_MT_SMTC
+ smtc_idle_loop_hook();
+#endif /* CONFIG_MIPS_MT_SMTC */
if (cpu_wait)
(*cpu_wait)();
+ }
preempt_enable_no_resched();
schedule();
preempt_disable();
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index f838b36..f3106d0 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -248,10 +248,20 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
break;
case FPC_EIR: { /* implementation / version register */
unsigned int flags;
+#ifdef CONFIG_MIPS_MT_SMTC
+ unsigned int irqflags;
+ unsigned int mtflags;
+#endif /* CONFIG_MIPS_MT_SMTC */
if (!cpu_has_fpu)
break;
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* Read-modify-write of Status must be atomic */
+ local_irq_save(irqflags);
+ mtflags = dmt();
+#endif /* CONFIG_MIPS_MT_SMTC */
+
preempt_disable();
if (cpu_has_mipsmt) {
unsigned int vpflags = dvpe();
@@ -266,6 +276,10 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
write_c0_status(flags);
}
+#ifdef CONFIG_MIPS_MT_SMTC
+ emt(mtflags);
+ local_irq_restore(irqflags);
+#endif /* CONFIG_MIPS_MT_SMTC */
preempt_enable();
break;
}
diff --git a/arch/mips/kernel/ptrace32.c b/arch/mips/kernel/ptrace32.c
index 0d5cf97..8704dc0 100644
--- a/arch/mips/kernel/ptrace32.c
+++ b/arch/mips/kernel/ptrace32.c
@@ -173,12 +173,22 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
break;
case FPC_EIR: { /* implementation / version register */
unsigned int flags;
+#ifdef CONFIG_MIPS_MT_SMTC
+ unsigned int irqflags;
+ unsigned int mtflags;
+#endif /* CONFIG_MIPS_MT_SMTC */
if (!cpu_has_fpu) {
tmp = 0;
break;
}
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* Read-modify-write of Status must be atomic */
+ local_irq_save(irqflags);
+ mtflags = dmt();
+#endif /* CONFIG_MIPS_MT_SMTC */
+
preempt_disable();
if (cpu_has_mipsmt) {
unsigned int vpflags = dvpe();
@@ -193,6 +203,10 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
__asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
write_c0_status(flags);
}
+#ifdef CONFIG_MIPS_MT_SMTC
+ emt(mtflags);
+ local_irq_restore(irqflags);
+#endif /* CONFIG_MIPS_MT_SMTC */
preempt_enable();
break;
}
diff --git a/arch/mips/kernel/r4k_switch.S b/arch/mips/kernel/r4k_switch.S
index d2afbd1..0b1b54a 100644
--- a/arch/mips/kernel/r4k_switch.S
+++ b/arch/mips/kernel/r4k_switch.S
@@ -88,7 +88,18 @@
PTR_ADDIU t0, $28, _THREAD_SIZE - 32
set_saved_sp t0, t1, t2
-
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* Read-modify-writes of Status must be atomic on a VPE */
+ mfc0 t2, CP0_TCSTATUS
+ ori t1, t2, TCSTATUS_IXMT
+ mtc0 t1, CP0_TCSTATUS
+ andi t2, t2, TCSTATUS_IXMT
+ ehb
+ DMT 8 # dmt t0
+ move t1,ra
+ jal mips_ihb
+ move ra,t1
+#endif /* CONFIG_MIPS_MT_SMTC */
mfc0 t1, CP0_STATUS /* Do we really need this? */
li a3, 0xff01
and t1, a3
@@ -97,6 +108,18 @@
and a2, a3
or a2, t1
mtc0 a2, CP0_STATUS
+#ifdef CONFIG_MIPS_MT_SMTC
+ ehb
+ andi t0, t0, VPECONTROL_TE
+ beqz t0, 1f
+ emt
+1:
+ mfc0 t1, CP0_TCSTATUS
+ xori t1, t1, TCSTATUS_IXMT
+ or t1, t1, t2
+ mtc0 t1, CP0_TCSTATUS
+ ehb
+#endif /* CONFIG_MIPS_MT_SMTC */
move v0, a0
jr ra
END(resume)
@@ -131,10 +154,19 @@ LEAF(_restore_fp)
#define FPU_DEFAULT 0x00000000
LEAF(_init_fpu)
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* Rather than manipulate per-VPE Status, set per-TC bit in TCStatus */
+ mfc0 t0, CP0_TCSTATUS
+ /* Bit position is the same for Status, TCStatus */
+ li t1, ST0_CU1
+ or t0, t1
+ mtc0 t0, CP0_TCSTATUS
+#else /* Normal MIPS CU1 enable */
mfc0 t0, CP0_STATUS
li t1, ST0_CU1
or t0, t1
mtc0 t0, CP0_STATUS
+#endif /* CONFIG_MIPS_MT_SMTC */
fpu_enable_hazard
li t1, FPU_DEFAULT
diff --git a/arch/mips/kernel/smp_mt.c b/arch/mips/kernel/smp-mt.c
index 993b8bf..19b8e4b 100644
--- a/arch/mips/kernel/smp_mt.c
+++ b/arch/mips/kernel/smp-mt.c
@@ -1,8 +1,4 @@
/*
- * Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved.
- *
- * Elizabeth Clarke (beth@mips.com)
- *
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
@@ -16,6 +12,10 @@
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
+ * Copyright (C) 2004, 05, 06 MIPS Technologies, Inc.
+ * Elizabeth Clarke (beth@mips.com)
+ * Ralf Baechle (ralf@linux-mips.org)
+ * Copyright (C) 2006 Ralf Baechle (ralf@linux-mips.org)
*/
#include <linux/kernel.h>
#include <linux/sched.h>
@@ -24,6 +24,7 @@
#include <linux/compiler.h>
#include <asm/atomic.h>
+#include <asm/cacheflush.h>
#include <asm/cpu.h>
#include <asm/processor.h>
#include <asm/system.h>
@@ -33,8 +34,8 @@
#include <asm/time.h>
#include <asm/mipsregs.h>
#include <asm/mipsmtregs.h>
-#include <asm/cacheflush.h>
-#include <asm/mips-boards/maltaint.h>
+#include <asm/mips_mt.h>
+#include <asm/mips-boards/maltaint.h> /* This is f*cking wrong */
#define MIPS_CPU_IPI_RESCHED_IRQ 0
#define MIPS_CPU_IPI_CALL_IRQ 1
@@ -66,6 +67,7 @@ void __init sanitize_tlb_entries(void)
if (!cpu_has_mipsmt)
return;
+ /* Enable VPC */
set_c0_mvpcontrol(MVPCONTROL_VPC);
back_to_back_c0_hazard();
@@ -106,12 +108,12 @@ void __init sanitize_tlb_entries(void)
static void ipi_resched_dispatch (struct pt_regs *regs)
{
- do_IRQ(MIPS_CPU_IPI_RESCHED_IRQ, regs);
+ do_IRQ(MIPSCPU_INT_BASE + MIPS_CPU_IPI_RESCHED_IRQ, regs);
}
static void ipi_call_dispatch (struct pt_regs *regs)
{
- do_IRQ(MIPS_CPU_IPI_CALL_IRQ, regs);
+ do_IRQ(MIPSCPU_INT_BASE + MIPS_CPU_IPI_CALL_IRQ, regs);
}
irqreturn_t ipi_resched_interrupt(int irq, void *dev_id, struct pt_regs *regs)
@@ -155,6 +157,8 @@ void plat_smp_setup(void)
dvpe();
dmt();
+ mips_mt_set_cpuoptions();
+
/* Put MVPE's into 'configuration state' */
set_c0_mvpcontrol(MVPCONTROL_VPC);
@@ -189,11 +193,13 @@ void plat_smp_setup(void)
if (i != 0) {
write_vpe_c0_status((read_c0_status() & ~(ST0_IM | ST0_IE | ST0_KSU)) | ST0_CU0);
- write_vpe_c0_cause(read_vpe_c0_cause() & ~CAUSEF_IP);
/* set config to be the same as vpe0, particularly kseg0 coherency alg */
write_vpe_c0_config( read_c0_config());
+ /* make sure there are no software interrupts pending */
+ write_vpe_c0_cause(read_vpe_c0_cause() & ~(C_SW1|C_SW0));
+
/* Propagate Config7 */
write_vpe_c0_config7(read_c0_config7());
}
@@ -233,16 +239,16 @@ void plat_smp_setup(void)
/* We'll wait until starting the secondaries before starting MVPE */
printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num);
+}
+void __init plat_prepare_cpus(unsigned int max_cpus)
+{
/* set up ipi interrupts */
if (cpu_has_vint) {
set_vi_handler (MIPS_CPU_IPI_RESCHED_IRQ, ipi_resched_dispatch);
set_vi_handler (MIPS_CPU_IPI_CALL_IRQ, ipi_call_dispatch);
}
-}
-void __init plat_prepare_cpus(unsigned int max_cpus)
-{
cpu_ipi_resched_irq = MIPSCPU_INT_BASE + MIPS_CPU_IPI_RESCHED_IRQ;
cpu_ipi_call_irq = MIPSCPU_INT_BASE + MIPS_CPU_IPI_CALL_IRQ;
@@ -287,7 +293,8 @@ void prom_boot_secondary(int cpu, struct task_struct *idle)
/* global pointer */
write_tc_gpr_gp((unsigned long)gp);
- flush_icache_range((unsigned long)gp, (unsigned long)(gp + 1));
+ flush_icache_range((unsigned long)gp,
+ (unsigned long)(gp + sizeof(struct thread_info)));
/* finally out of configuration and into chaos */
clear_c0_mvpcontrol(MVPCONTROL_VPC);
diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index 72a287a..d42f358 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -38,6 +38,10 @@
#include <asm/mmu_context.h>
#include <asm/smp.h>
+#ifdef CONFIG_MIPS_MT_SMTC
+#include <asm/mipsmtregs.h>
+#endif /* CONFIG_MIPS_MT_SMTC */
+
cpumask_t phys_cpu_present_map; /* Bitmask of available CPUs */
volatile cpumask_t cpu_callin_map; /* Bitmask of started secondaries */
cpumask_t cpu_online_map; /* Bitmask of currently online CPUs */
@@ -85,6 +89,10 @@ asmlinkage void start_secondary(void)
{
unsigned int cpu;
+#ifdef CONFIG_MIPS_MT_SMTC
+ /* Only do cpu_probe for first TC of CPU */
+ if ((read_c0_tcbind() & TCBIND_CURTC) == 0)
+#endif /* CONFIG_MIPS_MT_SMTC */
cpu_probe();
cpu_report();
per_cpu_trap_init();
@@ -179,11 +187,13 @@ int smp_call_function (void (*func) (void *info), void *info, int retry,
if (wait)
while (atomic_read(&data.finished) != cpus)
barrier();
+ call_data = NULL;
spin_unlock(&smp_call_lock);
return 0;
}
+
void smp_call_function_interrupt(void)
{
void (*func) (void *info) = call_data->func;
diff --git a/arch/mips/kernel/smtc-asm.S b/arch/mips/kernel/smtc-asm.S
new file mode 100644
index 0000000..c9d6519
--- /dev/null
+++ b/arch/mips/kernel/smtc-asm.S
@@ -0,0 +1,130 @@
+/*
+ * Assembly Language Functions for MIPS MT SMTC support
+ */
+
+/*
+ * This file should be built into the kernel only if CONFIG_MIPS_MT_SMTC is set. */
+
+#include <asm/regdef.h>
+#include <asm/asmmacro.h>
+#include <asm/stackframe.h>
+#include <asm/stackframe.h>
+
+/*
+ * "Software Interrupt" linkage.
+ *
+ * This is invoked when an "Interrupt" is sent from one TC to another,
+ * where the TC to be interrupted is halted, has it's Restart address
+ * and Status values saved by the "remote control" thread, then modified
+ * to cause execution to begin here, in kenel mode. This code then
+ * disguises the TC state as that of an exception and transfers
+ * control to the general exception or vectored interrupt handler.
+ */
+ .set noreorder
+
+/*
+The __smtc_ipi_vector would use k0 and k1 as temporaries and
+1) Set EXL (this is per-VPE, so this can't be done by proxy!)
+2) Restore the K/CU and IXMT bits to the pre "exception" state
+ (EXL means no interrupts and access to the kernel map).
+3) Set EPC to be the saved value of TCRestart.
+4) Jump to the exception handler entry point passed by the sender.
+
+CAN WE PROVE THAT WE WON'T DO THIS IF INTS DISABLED??
+*/
+
+/*
+ * Reviled and slandered vision: Set EXL and restore K/CU/IXMT
+ * state of pre-halt thread, then save everything and call
+ * thought some function pointer to imaginary_exception, which
+ * will parse a register value or memory message queue to
+ * deliver things like interprocessor interrupts. On return
+ * from that function, jump to the global ret_from_irq code
+ * to invoke the scheduler and return as appropriate.
+ */
+
+#define PT_PADSLOT4 (PT_R0-8)
+#define PT_PADSLOT5 (PT_R0-4)
+
+ .text
+ .align 5
+FEXPORT(__smtc_ipi_vector)
+ .set noat
+ /* Disable thread scheduling to make Status update atomic */
+ DMT 27 # dmt k1
+ ehb
+ /* Set EXL */
+ mfc0 k0,CP0_STATUS
+ ori k0,k0,ST0_EXL
+ mtc0 k0,CP0_STATUS
+ ehb
+ /* Thread scheduling now inhibited by EXL. Restore TE state. */
+ andi k1,k1,VPECONTROL_TE
+ beqz k1,1f
+ emt
+1:
+ /*
+ * The IPI sender has put some information on the anticipated
+ * kernel stack frame. If we were in user mode, this will be
+ * built above the saved kernel SP. If we were already in the
+ * kernel, it will be built above the current CPU SP.
+ *
+ * Were we in kernel mode, as indicated by CU0?
+ */
+ sll k1,k0,3
+ .set noreorder
+ bltz k1,2f
+ move k1,sp
+ .set reorder
+ /*
+ * If previously in user mode, set CU0 and use kernel stack.
+ */
+ li k1,ST0_CU0
+ or k1,k1,k0
+ mtc0 k1,CP0_STATUS
+ ehb
+ get_saved_sp
+ /* Interrupting TC will have pre-set values in slots in the new frame */
+2: subu k1,k1,PT_SIZE
+ /* Load TCStatus Value */
+ lw k0,PT_TCSTATUS(k1)
+ /* Write it to TCStatus to restore CU/KSU/IXMT state */
+ mtc0 k0,$2,1
+ ehb
+ lw k0,PT_EPC(k1)
+ mtc0 k0,CP0_EPC
+ /* Save all will redundantly recompute the SP, but use it for now */
+ SAVE_ALL
+ CLI
+ move a0,sp
+ /* Function to be invoked passed stack pad slot 5 */
+ lw t0,PT_PADSLOT5(sp)
+ /* Argument from sender passed in stack pad slot 4 */
+ lw a1,PT_PADSLOT4(sp)
+ jalr t0
+ nop
+ j ret_from_irq
+ nop
+
+/*
+ * Called from idle loop to provoke processing of queued IPIs
+ * First IPI message in queue passed as argument.
+ */
+
+LEAF(self_ipi)
+ /* Before anything else, block interrupts */
+ mfc0 t0,CP0_TCSTATUS
+ ori t1,t0,TCSTATUS_IXMT
+ mtc0 t1,CP0_TCSTATUS
+ ehb
+ /* We know we're in kernel mode, so prepare stack frame */
+ subu t1,sp,PT_SIZE
+ sw ra,PT_EPC(t1)
+ sw a0,PT_PADSLOT4(t1)
+ la t2,ipi_decode
+ sw t2,PT_PADSLOT5(t1)
+ /* Save pre-disable value of TCStatus */
+ sw t0,PT_TCSTATUS(t1)
+ j __smtc_ipi_vector
+ nop
+END(self_ipi)
diff --git a/arch/mips/kernel/smtc-proc.c b/arch/mips/kernel/smtc-proc.c
new file mode 100644
index 0000000..6f37099
--- /dev/null
+++ b/arch/mips/kernel/smtc-proc.c
@@ -0,0 +1,93 @@
+/*
+ * /proc hooks for SMTC kernel
+ * Copyright (C) 2005 Mips Technologies, Inc
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+
+#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <asm/hardirq.h>
+#include <asm/mmu_context.h>
+#include <asm/smp.h>
+#include <asm/mipsregs.h>
+#include <asm/cacheflush.h>
+#include <linux/proc_fs.h>
+
+#include <asm/smtc_proc.h>
+
+/*
+ * /proc diagnostic and statistics hooks
+ */
+
+/*
+ * Statistics gathered
+ */
+unsigned long selfipis[NR_CPUS];
+
+struct smtc_cpu_proc smtc_cpu_stats[NR_CPUS];
+
+static struct proc_dir_entry *smtc_stats;
+
+atomic_t smtc_fpu_recoveries;
+
+static int proc_read_smtc(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ int totalen = 0;
+ int len;
+ int i;
+ extern unsigned long ebase;
+
+ len = sprintf(page, "SMTC Status Word: 0x%08x\n", smtc_status);
+ totalen += len;
+ page += len;
+ len = sprintf(page, "Config7: 0x%08x\n", read_c0_config7());
+ totalen += len;
+ page += len;
+ len = sprintf(page, "EBASE: 0x%08lx\n", ebase);
+ totalen += len;
+ page += len;
+ len = sprintf(page, "Counter Interrupts taken per CPU (TC)\n");
+ totalen += len;
+ page += len;
+ for (i=0; i < NR_CPUS; i++) {
+ len = sprintf(page, "%d: %ld\n", i, smtc_cpu_stats[i].timerints);
+ totalen += len;
+ page += len;
+ }
+ len = sprintf(page, "Self-IPIs by CPU:\n");
+ totalen += len;
+ page += len;
+ for(i = 0; i < NR_CPUS; i++) {
+ len = sprintf(page, "%d: %ld\n", i, smtc_cpu_stats[i].selfipis);
+ totalen += len;
+ page += len;
+ }
+ len = sprintf(page, "%d Recoveries of \"stolen\" FPU\n",
+ atomic_read(&smtc_fpu_recoveries));
+ totalen += len;
+ page += len;
+
+ return totalen;
+}
+
+void init_smtc_stats(void)
+{
+ int i;
+
+ for (i=0; i<NR_CPUS; i++) {
+ smtc_cpu_stats[i].timerints = 0;
+ smtc_cpu_stats[i].selfipis = 0;
+ }
+
+ atomic_set(&smtc_fpu_recoveries, 0);
+
+ smtc_stats = create_proc_read_entry("smtc", 0444, NULL,
+ proc_read_smtc, NULL);
+}
diff --git a/arch/mips/kernel/smtc.c b/arch/mips/kernel/smtc.c
new file mode 100644
index 0000000..2e8e52c
--- /dev/null
+++ b/arch/mips/kernel/smtc.c
@@ -0,0 +1,1322 @@
+/* Copyright (C) 2004 Mips Technologies, Inc */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+
+#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <asm/hardirq.h>
+#include <asm/hazards.h>
+#include <asm/mmu_context.h>
+#include <asm/smp.h>
+#include <asm/mipsregs.h>
+#include <asm/cacheflush.h>
+#include <asm/time.h>
+#include <asm/addrspace.h>
+#include <asm/smtc.h>
+#include <asm/smtc_ipi.h>
+#include <asm/smtc_proc.h>
+
+/*
+ * This file should be built into the kernel only if CONFIG_MIPS_MT_SMTC is set.
+ */
+
+/*
+ * MIPSCPU_INT_BASE is identically defined in both
+ * asm-mips/mips-boards/maltaint.h and asm-mips/mips-boards/simint.h,
+ * but as yet there's no properly organized include structure that
+ * will ensure that the right *int.h file will be included for a
+ * given platform build.
+ */
+
+#define MIPSCPU_INT_BASE 16
+
+#define MIPS_CPU_IPI_IRQ 1
+
+#define LOCK_MT_PRA() \
+ local_irq_save(flags); \
+ mtflags = dmt()
+
+#define UNLOCK_MT_PRA() \
+ emt(mtflags); \
+ local_irq_restore(flags)
+
+#define LOCK_CORE_PRA() \
+ local_irq_save(flags); \
+ mtflags = dvpe()
+
+#define UNLOCK_CORE_PRA() \
+ evpe(mtflags); \
+ local_irq_restore(flags)
+
+/*
+ * Data structures purely associated with SMTC parallelism
+ */
+
+
+/*
+ * Table for tracking ASIDs whose lifetime is prolonged.
+ */
+
+asiduse smtc_live_asid[MAX_SMTC_TLBS][MAX_SMTC_ASIDS];
+
+/*
+ * Clock interrupt "latch" buffers, per "CPU"
+ */
+
+unsigned int ipi_timer_latch[NR_CPUS];
+
+/*
+ * Number of InterProcessor Interupt (IPI) message buffers to allocate
+ */
+
+#define IPIBUF_PER_CPU 4
+
+struct smtc_ipi_q IPIQ[NR_CPUS];
+struct smtc_ipi_q freeIPIq;
+
+
+/* Forward declarations */
+
+void ipi_decode(struct pt_regs *, struct smtc_ipi *);
+void post_direct_ipi(int cpu, struct smtc_ipi *pipi);
+void setup_cross_vpe_interrupts(void);
+void init_smtc_stats(void);
+
+/* Global SMTC Status */
+
+unsigned int smtc_status = 0;
+
+/* Boot command line configuration overrides */
+
+static int vpelimit = 0;
+static int tclimit = 0;
+static int ipibuffers = 0;
+static int nostlb = 0;
+static int asidmask = 0;
+unsigned long smtc_asid_mask = 0xff;
+
+static int __init maxvpes(char *str)
+{
+ get_option(&str, &vpelimit);
+ return 1;
+}
+
+static int __init maxtcs(char *str)
+{
+ get_option(&str, &tclimit);
+ return 1;
+}
+
+static int __init ipibufs(char *str)
+{
+ get_option(&str, &ipibuffers);
+ return 1;
+}
+
+static int __init stlb_disable(char *s)
+{
+ nostlb = 1;
+ return 1;
+}
+
+static int __init asidmask_set(char *str)
+{
+ get_option(&str, &asidmask);
+ switch(asidmask) {
+ case 0x1:
+ case 0x3:
+ case 0x7:
+ case 0xf:
+ case 0x1f:
+ case 0x3f:
+ case 0x7f:
+ case 0xff:
+ smtc_asid_mask = (unsigned long)asidmask;
+ break;
+ default:
+ printk("ILLEGAL ASID mask 0x%x from command line\n", asidmask);
+ }
+ return 1;
+}
+
+__setup("maxvpes=", maxvpes);
+__setup("maxtcs=", maxtcs);
+__setup("ipibufs=", ipibufs);
+__setup("nostlb", stlb_disable);
+__setup("asidmask=", asidmask_set);
+
+/* Enable additional debug checks before going into CPU idle loop */
+#define SMTC_IDLE_HOOK_DEBUG
+
+#ifdef SMTC_IDLE_HOOK_DEBUG
+
+static int hang_trig = 0;
+
+static int __init hangtrig_enable(char *s)
+{
+ hang_trig = 1;
+ return 1;
+}
+
+
+__setup("hangtrig", hangtrig_enable);
+
+#define DEFAULT_BLOCKED_IPI_LIMIT 32
+
+static int timerq_limit = DEFAULT_BLOCKED_IPI_LIMIT;
+
+static int __init tintq(char *str)
+{
+ get_option(&str, &timerq_limit);
+ return 1;
+}
+
+__setup("tintq=", tintq);
+
+int imstuckcount[2][8];
+/* vpemask represents IM/IE bits of per-VPE Status registers, low-to-high */
+int vpemask[2][8] = {{0,1,1,0,0,0,0,1},{0,1,0,0,0,0,0,1}};
+int tcnoprog[NR_CPUS];
+static atomic_t idle_hook_initialized = {0};
+static int clock_hang_reported[NR_CPUS];
+
+#endif /* SMTC_IDLE_HOOK_DEBUG */
+
+/* Initialize shared TLB - the should probably migrate to smtc_setup_cpus() */
+
+void __init sanitize_tlb_entries(void)
+{
+ printk("Deprecated sanitize_tlb_entries() invoked\n");
+}
+
+
+/*
+ * Configure shared TLB - VPC configuration bit must be set by caller
+ */
+
+void smtc_configure_tlb(void)
+{
+ int i,tlbsiz,vpes;
+ unsigned long mvpconf0;
+ unsigned long config1val;
+
+ /* Set up ASID preservation table */
+ for (vpes=0; vpes<MAX_SMTC_TLBS; vpes++) {
+ for(i = 0; i < MAX_SMTC_ASIDS; i++) {
+ smtc_live_asid[vpes][i] = 0;
+ }
+ }
+ mvpconf0 = read_c0_mvpconf0();
+
+ if ((vpes = ((mvpconf0 & MVPCONF0_PVPE)
+ >> MVPCONF0_PVPE_SHIFT) + 1) > 1) {
+ /* If we have multiple VPEs, try to share the TLB */
+ if ((mvpconf0 & MVPCONF0_TLBS) && !nostlb) {
+ /*
+ * If TLB sizing is programmable, shared TLB
+ * size is the total available complement.
+ * Otherwise, we have to take the sum of all
+ * static VPE TLB entries.
+ */
+ if ((tlbsiz = ((mvpconf0 & MVPCONF0_PTLBE)
+ >> MVPCONF0_PTLBE_SHIFT)) == 0) {
+ /*
+ * If there's more than one VPE, there had better
+ * be more than one TC, because we need one to bind
+ * to each VPE in turn to be able to read
+ * its configuration state!
+ */
+ settc(1);
+ /* Stop the TC from doing anything foolish */
+ write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
+ /* No need to un-Halt - that happens later anyway */
+ for (i=0; i < vpes; i++) {
+ write_tc_c0_tcbind(i);
+ /*
+ * To be 100% sure we're really getting the right
+ * information, we exit the configuration state
+ * and do an IHB after each rebinding.
+ */
+ write_c0_mvpcontrol(
+ read_c0_mvpcontrol() & ~ MVPCONTROL_VPC );
+ mips_ihb();
+ /*
+ * Only count if the MMU Type indicated is TLB
+ */
+ if(((read_vpe_c0_config() & MIPS_CONF_MT) >> 7) == 1) {
+ config1val = read_vpe_c0_config1();
+ tlbsiz += ((config1val >> 25) & 0x3f) + 1;
+ }
+
+ /* Put core back in configuration state */
+ write_c0_mvpcontrol(
+ read_c0_mvpcontrol() | MVPCONTROL_VPC );
+ mips_ihb();
+ }
+ }
+ write_c0_mvpcontrol(read_c0_mvpcontrol() | MVPCONTROL_STLB);
+
+ /*
+ * Setup kernel data structures to use software total,
+ * rather than read the per-VPE Config1 value. The values
+ * for "CPU 0" gets copied to all the other CPUs as part
+ * of their initialization in smtc_cpu_setup().
+ */
+
+ tlbsiz = tlbsiz & 0x3f; /* MIPS32 limits TLB indices to 64 */
+ cpu_data[0].tlbsize = tlbsiz;
+ smtc_status |= SMTC_TLB_SHARED;
+
+ printk("TLB of %d entry pairs shared by %d VPEs\n",
+ tlbsiz, vpes);
+ } else {
+ printk("WARNING: TLB Not Sharable on SMTC Boot!\n");
+ }
+ }
+}
+
+
+/*
+ * Incrementally build the CPU map out of constituent MIPS MT cores,
+ * using the specified available VPEs and TCs. Plaform code needs
+ * to ensure that each MIPS MT core invokes this routine on reset,
+ * one at a time(!).
+ *
+ * This version of the build_cpu_map and prepare_cpus routines assumes
+ * that *all* TCs of a MIPS MT core will be used for Linux, and that
+ * they will be spread across *all* available VPEs (to minimise the
+ * loss of efficiency due to exception service serialization).
+ * An improved version would pick up configuration information and
+ * possibly leave some TCs/VPEs as "slave" processors.
+ *
+ * Use c0_MVPConf0 to find out how many TCs are available, setting up
+ * phys_cpu_present_map and the logical/physical mappings.
+ */
+
+int __init mipsmt_build_cpu_map(int start_cpu_slot)
+{
+ int i, ntcs;
+
+ /*
+ * The CPU map isn't actually used for anything at this point,
+ * so it's not clear what else we should do apart from set
+ * everything up so that "logical" = "physical".
+ */
+ ntcs = ((read_c0_mvpconf0() & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
+ for (i=start_cpu_slot; i<NR_CPUS && i<ntcs; i++) {
+ cpu_set(i, phys_cpu_present_map);
+ __cpu_number_map[i] = i;
+ __cpu_logical_map[i] = i;
+ }
+ /* Initialize map of CPUs with FPUs */
+ cpus_clear(mt_fpu_cpumask);
+
+ /* One of those TC's is the one booting, and not a secondary... */
+ printk("%i available secondary CPU TC(s)\n", i - 1);
+
+ return i;
+}
+
+/*
+ * Common setup before any secondaries are started
+ * Make sure all CPU's are in a sensible state before we boot any of the
+ * secondaries.
+ *
+ * For MIPS MT "SMTC" operation, we set up all TCs, spread as evenly
+ * as possible across the available VPEs.
+ */
+
+static void smtc_tc_setup(int vpe, int tc, int cpu)
+{
+ settc(tc);
+ write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
+ write_tc_c0_tcstatus((read_tc_c0_tcstatus()
+ & ~(TCSTATUS_TKSU | TCSTATUS_DA | TCSTATUS_IXMT))
+ | TCSTATUS_A);
+ write_tc_c0_tccontext(0);
+ /* Bind tc to vpe */
+ write_tc_c0_tcbind(vpe);
+ /* In general, all TCs should have the same cpu_data indications */
+ memcpy(&cpu_data[cpu], &cpu_data[0], sizeof(struct cpuinfo_mips));
+ /* For 34Kf, start with TC/CPU 0 as sole owner of single FPU context */
+ if (cpu_data[0].cputype == CPU_34K)
+ cpu_data[cpu].options &= ~MIPS_CPU_FPU;
+ cpu_data[cpu].vpe_id = vpe;
+ cpu_data[cpu].tc_id = tc;
+}
+
+
+void mipsmt_prepare_cpus(void)
+{
+ int i, vpe, tc, ntc, nvpe, tcpervpe, slop, cpu;
+ unsigned long flags;
+ unsigned long val;
+ int nipi;
+ struct smtc_ipi *pipi;
+
+ /* disable interrupts so we can disable MT */
+ local_irq_save(flags);
+ /* disable MT so we can configure */
+ dvpe();
+ dmt();
+
+ freeIPIq.lock = SPIN_LOCK_UNLOCKED;
+
+ /*
+ * We probably don't have as many VPEs as we do SMP "CPUs",
+ * but it's possible - and in any case we'll never use more!
+ */
+ for (i=0; i<NR_CPUS; i++) {
+ IPIQ[i].head = IPIQ[i].tail = NULL;
+ IPIQ[i].lock = SPIN_LOCK_UNLOCKED;
+ IPIQ[i].depth = 0;
+ ipi_timer_latch[i] = 0;
+ }
+
+ /* cpu_data index starts at zero */
+ cpu = 0;
+ cpu_data[cpu].vpe_id = 0;
+ cpu_data[cpu].tc_id = 0;
+ cpu++;
+
+ /* Report on boot-time options */
+ mips_mt_set_cpuoptions ();
+ if (vpelimit > 0)
+ printk("Limit of %d VPEs set\n", vpelimit);
+ if (tclimit > 0)
+ printk("Limit of %d TCs set\n", tclimit);
+ if (nostlb) {
+ printk("Shared TLB Use Inhibited - UNSAFE for Multi-VPE Operation\n");
+ }
+ if (asidmask)
+ printk("ASID mask value override to 0x%x\n", asidmask);
+
+ /* Temporary */
+#ifdef SMTC_IDLE_HOOK_DEBUG
+ if (hang_trig)
+ printk("Logic Analyser Trigger on suspected TC hang\n");
+#endif /* SMTC_IDLE_HOOK_DEBUG */
+
+ /* Put MVPE's into 'configuration state' */
+ write_c0_mvpcontrol( read_c0_mvpcontrol() | MVPCONTROL_VPC );
+
+ val = read_c0_mvpconf0();
+ nvpe = ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1;
+ if (vpelimit > 0 && nvpe > vpelimit)
+ nvpe = vpelimit;
+ ntc = ((val & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
+ if (ntc > NR_CPUS)
+ ntc = NR_CPUS;
+ if (tclimit > 0 && ntc > tclimit)
+ ntc = tclimit;
+ tcpervpe = ntc / nvpe;
+ slop = ntc % nvpe; /* Residual TCs, < NVPE */
+
+ /* Set up shared TLB */
+ smtc_configure_tlb();
+
+ for (tc = 0, vpe = 0 ; (vpe < nvpe) && (tc < ntc) ; vpe++) {
+ /*
+ * Set the MVP bits.
+ */
+ settc(tc);
+ write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_MVP);
+ if (vpe != 0)
+ printk(", ");
+ printk("VPE %d: TC", vpe);
+ for (i = 0; i < tcpervpe; i++) {
+ /*
+ * TC 0 is bound to VPE 0 at reset,
+ * and is presumably executing this
+ * code. Leave it alone!
+ */
+ if (tc != 0) {
+ smtc_tc_setup(vpe,tc, cpu);
+ cpu++;
+ }
+ printk(" %d", tc);
+ tc++;
+ }
+ if (slop) {
+ if (tc != 0) {
+ smtc_tc_setup(vpe,tc, cpu);
+ cpu++;
+ }
+ printk(" %d", tc);
+ tc++;
+ slop--;
+ }
+ if (vpe != 0) {
+ /*
+ * Clear any stale software interrupts from VPE's Cause
+ */
+ write_vpe_c0_cause(0);
+
+ /*
+ * Clear ERL/EXL of VPEs other than 0
+ * and set restricted interrupt enable/mask.
+ */
+ write_vpe_c0_status((read_vpe_c0_status()
+ & ~(ST0_BEV | ST0_ERL | ST0_EXL | ST0_IM))
+ | (STATUSF_IP0 | STATUSF_IP1 | STATUSF_IP7
+ | ST0_IE));
+ /*
+ * set config to be the same as vpe0,
+ * particularly kseg0 coherency alg
+ */
+ write_vpe_c0_config(read_c0_config());
+ /* Clear any pending timer interrupt */
+ write_vpe_c0_compare(0);
+ /* Propagate Config7 */
+ write_vpe_c0_config7(read_c0_config7());
+ }
+ /* enable multi-threading within VPE */
+ write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() | VPECONTROL_TE);
+ /* enable the VPE */
+ write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA);
+ }
+
+ /*
+ * Pull any physically present but unused TCs out of circulation.
+ */
+ while (tc < (((val & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1)) {
+ cpu_clear(tc, phys_cpu_present_map);
+ cpu_clear(tc, cpu_present_map);
+ tc++;
+ }
+
+ /* release config state */
+ write_c0_mvpcontrol( read_c0_mvpcontrol() & ~ MVPCONTROL_VPC );
+
+ printk("\n");
+
+ /* Set up coprocessor affinity CPU mask(s) */
+
+ for (tc = 0; tc < ntc; tc++) {
+ if(cpu_data[tc].options & MIPS_CPU_FPU)
+ cpu_set(tc, mt_fpu_cpumask);
+ }
+
+ /* set up ipi interrupts... */
+
+ /* If we have multiple VPEs running, set up the cross-VPE interrupt */
+
+ if (nvpe > 1)
+ setup_cross_vpe_interrupts();
+
+ /* Set up queue of free IPI "messages". */
+ nipi = NR_CPUS * IPIBUF_PER_CPU;
+ if (ipibuffers > 0)
+ nipi = ipibuffers;
+
+ pipi = kmalloc(nipi *sizeof(struct smtc_ipi), GFP_KERNEL);
+ if (pipi == NULL)
+ panic("kmalloc of IPI message buffers failed\n");
+ else
+ printk("IPI buffer pool of %d buffers\n", nipi);
+ for (i = 0; i < nipi; i++) {
+ smtc_ipi_nq(&freeIPIq, pipi);
+ pipi++;
+ }
+
+ /* Arm multithreading and enable other VPEs - but all TCs are Halted */
+ emt(EMT_ENABLE);
+ evpe(EVPE_ENABLE);
+ local_irq_restore(flags);
+ /* Initialize SMTC /proc statistics/diagnostics */
+ init_smtc_stats();
+}
+
+
+/*
+ * Setup the PC, SP, and GP of a secondary processor and start it
+ * running!
+ * smp_bootstrap is the place to resume from
+ * __KSTK_TOS(idle) is apparently the stack pointer
+ * (unsigned long)idle->thread_info the gp
+ *
+ */
+void smtc_boot_secondary(int cpu, struct task_struct *idle)
+{
+ extern u32 kernelsp[NR_CPUS];
+ long flags;
+ int mtflags;
+
+ LOCK_MT_PRA();
+ if (cpu_data[cpu].vpe_id != cpu_data[smp_processor_id()].vpe_id) {
+ dvpe();
+ }
+ settc(cpu_data[cpu].tc_id);
+
+ /* pc */
+ write_tc_c0_tcrestart((unsigned long)&smp_bootstrap);
+
+ /* stack pointer */
+ kernelsp[cpu] = __KSTK_TOS(idle);
+ write_tc_gpr_sp(__KSTK_TOS(idle));
+
+ /* global pointer */
+ write_tc_gpr_gp((unsigned long)idle->thread_info);
+
+ smtc_status |= SMTC_MTC_ACTIVE;
+ write_tc_c0_tchalt(0);
+ if (cpu_data[cpu].vpe_id != cpu_data[smp_processor_id()].vpe_id) {
+ evpe(EVPE_ENABLE);
+ }
+ UNLOCK_MT_PRA();
+}
+
+void smtc_init_secondary(void)
+{
+ /*
+ * Start timer on secondary VPEs if necessary.
+ * mips_timer_setup should already have been invoked by init/main
+ * on "boot" TC. Like per_cpu_trap_init() hack, this assumes that
+ * SMTC init code assigns TCs consdecutively and in ascending order
+ * to across available VPEs.
+ */
+ if(((read_c0_tcbind() & TCBIND_CURTC) != 0)
+ && ((read_c0_tcbind() & TCBIND_CURVPE)
+ != cpu_data[smp_processor_id() - 1].vpe_id)){
+ write_c0_compare (read_c0_count() + mips_hpt_frequency/HZ);
+ }
+
+ local_irq_enable();
+}
+
+void smtc_smp_finish(void)
+{
+ printk("TC %d going on-line as CPU %d\n",
+ cpu_data[smp_processor_id()].tc_id, smp_processor_id());
+}
+
+void smtc_cpus_done(void)
+{
+}
+
+/*
+ * Support for SMTC-optimized driver IRQ registration
+ */
+
+/*
+ * SMTC Kernel needs to manipulate low-level CPU interrupt mask
+ * in do_IRQ. These are passed in setup_irq_smtc() and stored
+ * in this table.
+ */
+
+int setup_irq_smtc(unsigned int irq, struct irqaction * new,
+ unsigned long hwmask)
+{
+ irq_hwmask[irq] = hwmask;
+
+ return setup_irq(irq, new);
+}
+
+/*
+ * IPI model for SMTC is tricky, because interrupts aren't TC-specific.
+ * Within a VPE one TC can interrupt another by different approaches.
+ * The easiest to get right would probably be to make all TCs except
+ * the target IXMT and set a software interrupt, but an IXMT-based
+ * scheme requires that a handler must run before a new IPI could
+ * be sent, which would break the "broadcast" loops in MIPS MT.
+ * A more gonzo approach within a VPE is to halt the TC, extract
+ * its Restart, Status, and a couple of GPRs, and program the Restart
+ * address to emulate an interrupt.
+ *
+ * Within a VPE, one can be confident that the target TC isn't in
+ * a critical EXL state when halted, since the write to the Halt
+ * register could not have issued on the writing thread if the
+ * halting thread had EXL set. So k0 and k1 of the target TC
+ * can be used by the injection code. Across VPEs, one can't
+ * be certain that the target TC isn't in a critical exception
+ * state. So we try a two-step process of sending a software
+ * interrupt to the target VPE, which either handles the event
+ * itself (if it was the target) or injects the event within
+ * the VPE.
+ */
+
+void smtc_ipi_qdump(void)
+{
+ int i;
+
+ for (i = 0; i < NR_CPUS ;i++) {
+ printk("IPIQ[%d]: head = 0x%x, tail = 0x%x, depth = %d\n",
+ i, (unsigned)IPIQ[i].head, (unsigned)IPIQ[i].tail,
+ IPIQ[i].depth);
+ }
+}
+
+/*
+ * The standard atomic.h primitives don't quite do what we want
+ * here: We need an atomic add-and-return-previous-value (which
+ * could be done with atomic_add_return and a decrement) and an
+ * atomic set/zero-and-return-previous-value (which can't really
+ * be done with the atomic.h primitives). And since this is
+ * MIPS MT, we can assume that we have LL/SC.
+ */
+static __inline__ int atomic_postincrement(unsigned int *pv)
+{
+ unsigned long result;
+
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ "1: ll %0, %2 \n"
+ " addu %1, %0, 1 \n"
+ " sc %1, %2 \n"
+ " beqz %1, 1b \n"
+ " sync \n"
+ : "=&r" (result), "=&r" (temp), "=m" (*pv)
+ : "m" (*pv)
+ : "memory");
+
+ return result;
+}
+
+/* No longer used in IPI dispatch, but retained for future recycling */
+
+static __inline__ int atomic_postclear(unsigned int *pv)
+{
+ unsigned long result;
+
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ "1: ll %0, %2 \n"
+ " or %1, $0, $0 \n"
+ " sc %1, %2 \n"
+ " beqz %1, 1b \n"
+ " sync \n"
+ : "=&r" (result), "=&r" (temp), "=m" (*pv)
+ : "m" (*pv)
+ : "memory");
+
+ return result;
+}
+
+
+void smtc_send_ipi(int cpu, int type, unsigned int action)
+{
+ int tcstatus;
+ struct smtc_ipi *pipi;
+ long flags;
+ int mtflags;
+
+ if (cpu == smp_processor_id()) {
+ printk("Cannot Send IPI to self!\n");
+ return;
+ }
+ /* Set up a descriptor, to be delivered either promptly or queued */
+ pipi = smtc_ipi_dq(&freeIPIq);
+ if (pipi == NULL) {
+ bust_spinlocks(1);
+ mips_mt_regdump(dvpe());
+ panic("IPI Msg. Buffers Depleted\n");
+ }
+ pipi->type = type;
+ pipi->arg = (void *)action;
+ pipi->dest = cpu;
+ if (cpu_data[cpu].vpe_id != cpu_data[smp_processor_id()].vpe_id) {
+ /* If not on same VPE, enqueue and send cross-VPE interupt */
+ smtc_ipi_nq(&IPIQ[cpu], pipi);
+ LOCK_CORE_PRA();
+ settc(cpu_data[cpu].tc_id);
+ write_vpe_c0_cause(read_vpe_c0_cause() | C_SW1);
+ UNLOCK_CORE_PRA();
+ } else {
+ /*
+ * Not sufficient to do a LOCK_MT_PRA (dmt) here,
+ * since ASID shootdown on the other VPE may
+ * collide with this operation.
+ */
+ LOCK_CORE_PRA();
+ settc(cpu_data[cpu].tc_id);
+ /* Halt the targeted TC */
+ write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
+
+ /*
+ * Inspect TCStatus - if IXMT is set, we have to queue
+ * a message. Otherwise, we set up the "interrupt"
+ * of the other TC
+ */
+ tcstatus = read_tc_c0_tcstatus();
+
+ if ((tcstatus & TCSTATUS_IXMT) != 0) {
+ /*
+ * Spin-waiting here can deadlock,
+ * so we queue the message for the target TC.
+ */
+ write_tc_c0_tchalt(0);
+ UNLOCK_CORE_PRA();
+ /* Try to reduce redundant timer interrupt messages */
+ if(type == SMTC_CLOCK_TICK) {
+ if(atomic_postincrement(&ipi_timer_latch[cpu])!=0) {
+ smtc_ipi_nq(&freeIPIq, pipi);
+ return;
+ }
+ }
+ smtc_ipi_nq(&IPIQ[cpu], pipi);
+ } else {
+ post_direct_ipi(cpu, pipi);
+ write_tc_c0_tchalt(0);
+ UNLOCK_CORE_PRA();
+ }
+ }
+}
+
+/*
+ * Send IPI message to Halted TC, TargTC/TargVPE already having been set
+ */
+void post_direct_ipi(int cpu, struct smtc_ipi *pipi)
+{
+ struct pt_regs *kstack;
+ unsigned long tcstatus;
+ unsigned long tcrestart;
+ extern u32 kernelsp[NR_CPUS];
+ extern void __smtc_ipi_vector(void);
+
+ /* Extract Status, EPC from halted TC */
+ tcstatus = read_tc_c0_tcstatus();
+ tcrestart = read_tc_c0_tcrestart();
+ /* If TCRestart indicates a WAIT instruction, advance the PC */
+ if ((tcrestart & 0x80000000)
+ && ((*(unsigned int *)tcrestart & 0xfe00003f) == 0x42000020)) {
+ tcrestart += 4;
+ }
+ /*
+ * Save on TC's future kernel stack
+ *
+ * CU bit of Status is indicator that TC was
+ * already running on a kernel stack...
+ */
+ if(tcstatus & ST0_CU0) {
+ /* Note that this "- 1" is pointer arithmetic */
+ kstack = ((struct pt_regs *)read_tc_gpr_sp()) - 1;
+ } else {
+ kstack = ((struct pt_regs *)kernelsp[cpu]) - 1;
+ }
+
+ kstack->cp0_epc = (long)tcrestart;
+ /* Save TCStatus */
+ kstack->cp0_tcstatus = tcstatus;
+ /* Pass token of operation to be performed kernel stack pad area */
+ kstack->pad0[4] = (unsigned long)pipi;
+ /* Pass address of function to be called likewise */
+ kstack->pad0[5] = (unsigned long)&ipi_decode;
+ /* Set interrupt exempt and kernel mode */
+ tcstatus |= TCSTATUS_IXMT;
+ tcstatus &= ~TCSTATUS_TKSU;
+ write_tc_c0_tcstatus(tcstatus);
+ ehb();
+ /* Set TC Restart address to be SMTC IPI vector */
+ write_tc_c0_tcrestart(__smtc_ipi_vector);
+}
+
+void ipi_resched_interrupt(struct pt_regs *regs)
+{
+ /* Return from interrupt should be enough to cause scheduler check */
+}
+
+
+void ipi_call_interrupt(struct pt_regs *regs)
+{
+ /* Invoke generic function invocation code in smp.c */
+ smp_call_function_interrupt();
+}
+
+void ipi_decode(struct pt_regs *regs, struct smtc_ipi *pipi)
+{
+ void *arg_copy = pipi->arg;
+ int type_copy = pipi->type;
+ int dest_copy = pipi->dest;
+
+ smtc_ipi_nq(&freeIPIq, pipi);
+ switch (type_copy) {
+ case SMTC_CLOCK_TICK:
+ /* Invoke Clock "Interrupt" */
+ ipi_timer_latch[dest_copy] = 0;
+#ifdef SMTC_IDLE_HOOK_DEBUG
+ clock_hang_reported[dest_copy] = 0;
+#endif /* SMTC_IDLE_HOOK_DEBUG */
+ local_timer_interrupt(0, NULL, regs);
+ break;
+ case LINUX_SMP_IPI:
+ switch ((int)arg_copy) {
+ case SMP_RESCHEDULE_YOURSELF:
+ ipi_resched_interrupt(regs);
+ break;
+ case SMP_CALL_FUNCTION:
+ ipi_call_interrupt(regs);
+ break;
+ default:
+ printk("Impossible SMTC IPI Argument 0x%x\n",
+ (int)arg_copy);
+ break;
+ }
+ break;
+ default:
+ printk("Impossible SMTC IPI Type 0x%x\n", type_copy);
+ break;
+ }
+}
+
+void deferred_smtc_ipi(struct pt_regs *regs)
+{
+ struct smtc_ipi *pipi;
+ unsigned long flags;
+/* DEBUG */
+ int q = smp_processor_id();
+
+ /*
+ * Test is not atomic, but much faster than a dequeue,
+ * and the vast majority of invocations will have a null queue.
+ */
+ if(IPIQ[q].head != NULL) {
+ while((pipi = smtc_ipi_dq(&IPIQ[q])) != NULL) {
+ /* ipi_decode() should be called with interrupts off */
+ local_irq_save(flags);
+ ipi_decode(regs, pipi);
+ local_irq_restore(flags);
+ }
+ }
+}
+
+/*
+ * Send clock tick to all TCs except the one executing the funtion
+ */
+
+void smtc_timer_broadcast(int vpe)
+{
+ int cpu;
+ int myTC = cpu_data[smp_processor_id()].tc_id;
+ int myVPE = cpu_data[smp_processor_id()].vpe_id;
+
+ smtc_cpu_stats[smp_processor_id()].timerints++;
+
+ for_each_online_cpu(cpu) {
+ if (cpu_data[cpu].vpe_id == myVPE &&
+ cpu_data[cpu].tc_id != myTC)
+ smtc_send_ipi(cpu, SMTC_CLOCK_TICK, 0);
+ }
+}
+
+/*
+ * Cross-VPE interrupts in the SMTC prototype use "software interrupts"
+ * set via cross-VPE MTTR manipulation of the Cause register. It would be
+ * in some regards preferable to have external logic for "doorbell" hardware
+ * interrupts.
+ */
+
+static int cpu_ipi_irq = MIPSCPU_INT_BASE + MIPS_CPU_IPI_IRQ;
+
+static irqreturn_t ipi_interrupt(int irq, void *dev_idm, struct pt_regs *regs)
+{
+ int my_vpe = cpu_data[smp_processor_id()].vpe_id;
+ int my_tc = cpu_data[smp_processor_id()].tc_id;
+ int cpu;
+ struct smtc_ipi *pipi;
+ unsigned long tcstatus;
+ int sent;
+ long flags;
+ unsigned int mtflags;
+ unsigned int vpflags;
+
+ /*
+ * So long as cross-VPE interrupts are done via
+ * MFTR/MTTR read-modify-writes of Cause, we need
+ * to stop other VPEs whenever the local VPE does
+ * anything similar.
+ */
+ local_irq_save(flags);
+ vpflags = dvpe();
+ clear_c0_cause(0x100 << MIPS_CPU_IPI_IRQ);
+ set_c0_status(0x100 << MIPS_CPU_IPI_IRQ);
+ irq_enable_hazard();
+ evpe(vpflags);
+ local_irq_restore(flags);
+
+ /*
+ * Cross-VPE Interrupt handler: Try to directly deliver IPIs
+ * queued for TCs on this VPE other than the current one.
+ * Return-from-interrupt should cause us to drain the queue
+ * for the current TC, so we ought not to have to do it explicitly here.
+ */
+
+ for_each_online_cpu(cpu) {
+ if (cpu_data[cpu].vpe_id != my_vpe)
+ continue;
+
+ pipi = smtc_ipi_dq(&IPIQ[cpu]);
+ if (pipi != NULL) {
+ if (cpu_data[cpu].tc_id != my_tc) {
+ sent = 0;
+ LOCK_MT_PRA();
+ settc(cpu_data[cpu].tc_id);
+ write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
+ tcstatus = read_tc_c0_tcstatus();
+ if ((tcstatus & TCSTATUS_IXMT) == 0) {
+ post_direct_ipi(cpu, pipi);
+ sent = 1;
+ }
+ write_tc_c0_tchalt(0);
+ UNLOCK_MT_PRA();
+ if (!sent) {
+ smtc_ipi_req(&IPIQ[cpu], pipi);
+ }
+ } else {
+ /*
+ * ipi_decode() should be called
+ * with interrupts off
+ */
+ local_irq_save(flags);
+ ipi_decode(regs, pipi);
+ local_irq_restore(flags);
+ }
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void ipi_irq_dispatch(struct pt_regs *regs)
+{
+ do_IRQ(cpu_ipi_irq, regs);
+}
+
+static struct irqaction irq_ipi;
+
+void setup_cross_vpe_interrupts(void)
+{
+ if (!cpu_has_vint)
+ panic("SMTC Kernel requires Vectored Interupt support");
+
+ set_vi_handler(MIPS_CPU_IPI_IRQ, ipi_irq_dispatch);
+
+ irq_ipi.handler = ipi_interrupt;
+ irq_ipi.flags = SA_INTERRUPT;
+ irq_ipi.name = "SMTC_IPI";
+
+ setup_irq_smtc(cpu_ipi_irq, &irq_ipi, (0x100 << MIPS_CPU_IPI_IRQ));
+
+ irq_desc[cpu_ipi_irq].status |= IRQ_PER_CPU;
+}
+
+/*
+ * SMTC-specific hacks invoked from elsewhere in the kernel.
+ */
+
+void smtc_idle_loop_hook(void)
+{
+#ifdef SMTC_IDLE_HOOK_DEBUG
+ int im;
+ int flags;
+ int mtflags;
+ int bit;
+ int vpe;
+ int tc;
+ int hook_ntcs;
+ /*
+ * printk within DMT-protected regions can deadlock,
+ * so buffer diagnostic messages for later output.
+ */
+ char *pdb_msg;
+ char id_ho_db_msg[768]; /* worst-case use should be less than 700 */
+
+ if (atomic_read(&idle_hook_initialized) == 0) { /* fast test */
+ if (atomic_add_return(1, &idle_hook_initialized) == 1) {
+ int mvpconf0;
+ /* Tedious stuff to just do once */
+ mvpconf0 = read_c0_mvpconf0();
+ hook_ntcs = ((mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT) + 1;
+ if (hook_ntcs > NR_CPUS)
+ hook_ntcs = NR_CPUS;
+ for (tc = 0; tc < hook_ntcs; tc++) {
+ tcnoprog[tc] = 0;
+ clock_hang_reported[tc] = 0;
+ }
+ for (vpe = 0; vpe < 2; vpe++)
+ for (im = 0; im < 8; im++)
+ imstuckcount[vpe][im] = 0;
+ printk("Idle loop test hook initialized for %d TCs\n", hook_ntcs);
+ atomic_set(&idle_hook_initialized, 1000);
+ } else {
+ /* Someone else is initializing in parallel - let 'em finish */
+ while (atomic_read(&idle_hook_initialized) < 1000)
+ ;
+ }
+ }
+
+ /* Have we stupidly left IXMT set somewhere? */
+ if (read_c0_tcstatus() & 0x400) {
+ write_c0_tcstatus(read_c0_tcstatus() & ~0x400);
+ ehb();
+ printk("Dangling IXMT in cpu_idle()\n");
+ }
+
+ /* Have we stupidly left an IM bit turned off? */
+#define IM_LIMIT 2000
+ local_irq_save(flags);
+ mtflags = dmt();
+ pdb_msg = &id_ho_db_msg[0];
+ im = read_c0_status();
+ vpe = cpu_data[smp_processor_id()].vpe_id;
+ for (bit = 0; bit < 8; bit++) {
+ /*
+ * In current prototype, I/O interrupts
+ * are masked for VPE > 0
+ */
+ if (vpemask[vpe][bit]) {
+ if (!(im & (0x100 << bit)))
+ imstuckcount[vpe][bit]++;
+ else
+ imstuckcount[vpe][bit] = 0;
+ if (imstuckcount[vpe][bit] > IM_LIMIT) {
+ set_c0_status(0x100 << bit);
+ ehb();
+ imstuckcount[vpe][bit] = 0;
+ pdb_msg += sprintf(pdb_msg,
+ "Dangling IM %d fixed for VPE %d\n", bit,
+ vpe);
+ }
+ }
+ }
+
+ /*
+ * Now that we limit outstanding timer IPIs, check for hung TC
+ */
+ for (tc = 0; tc < NR_CPUS; tc++) {
+ /* Don't check ourself - we'll dequeue IPIs just below */
+ if ((tc != smp_processor_id()) &&
+ ipi_timer_latch[tc] > timerq_limit) {
+ if (clock_hang_reported[tc] == 0) {
+ pdb_msg += sprintf(pdb_msg,
+ "TC %d looks hung with timer latch at %d\n",
+ tc, ipi_timer_latch[tc]);
+ clock_hang_reported[tc]++;
+ }
+ }
+ }
+ emt(mtflags);
+ local_irq_restore(flags);
+ if (pdb_msg != &id_ho_db_msg[0])
+ printk("CPU%d: %s", smp_processor_id(), id_ho_db_msg);
+#endif /* SMTC_IDLE_HOOK_DEBUG */
+ /*
+ * To the extent that we've ever turned interrupts off,
+ * we may have accumulated deferred IPIs. This is subtle.
+ * If we use the smtc_ipi_qdepth() macro, we'll get an
+ * exact number - but we'll also disable interrupts
+ * and create a window of failure where a new IPI gets
+ * queued after we test the depth but before we re-enable
+ * interrupts. So long as IXMT never gets set, however,
+ * we should be OK: If we pick up something and dispatch
+ * it here, that's great. If we see nothing, but concurrent
+ * with this operation, another TC sends us an IPI, IXMT
+ * is clear, and we'll handle it as a real pseudo-interrupt
+ * and not a pseudo-pseudo interrupt.
+ */
+ if (IPIQ[smp_processor_id()].depth > 0) {
+ struct smtc_ipi *pipi;
+ extern void self_ipi(struct smtc_ipi *);
+
+ if ((pipi = smtc_ipi_dq(&IPIQ[smp_processor_id()])) != NULL) {
+ self_ipi(pipi);
+ smtc_cpu_stats[smp_processor_id()].selfipis++;
+ }
+ }
+}
+
+void smtc_soft_dump(void)
+{
+ int i;
+
+ printk("Counter Interrupts taken per CPU (TC)\n");
+ for (i=0; i < NR_CPUS; i++) {
+ printk("%d: %ld\n", i, smtc_cpu_stats[i].timerints);
+ }
+ printk("Self-IPI invocations:\n");
+ for (i=0; i < NR_CPUS; i++) {
+ printk("%d: %ld\n", i, smtc_cpu_stats[i].selfipis);
+ }
+ smtc_ipi_qdump();
+ printk("Timer IPI Backlogs:\n");
+ for (i=0; i < NR_CPUS; i++) {
+ printk("%d: %d\n", i, ipi_timer_latch[i]);
+ }
+ printk("%d Recoveries of \"stolen\" FPU\n",
+ atomic_read(&smtc_fpu_recoveries));
+}
+
+
+/*
+ * TLB management routines special to SMTC
+ */
+
+void smtc_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu)
+{
+ unsigned long flags, mtflags, tcstat, prevhalt, asid;
+ int tlb, i;
+
+ /*
+ * It would be nice to be able to use a spinlock here,
+ * but this is invoked from within TLB flush routines
+ * that protect themselves with DVPE, so if a lock is
+ * held by another TC, it'll never be freed.
+ *
+ * DVPE/DMT must not be done with interrupts enabled,
+ * so even so most callers will already have disabled
+ * them, let's be really careful...
+ */
+
+ local_irq_save(flags);
+ if (smtc_status & SMTC_TLB_SHARED) {
+ mtflags = dvpe();
+ tlb = 0;
+ } else {
+ mtflags = dmt();
+ tlb = cpu_data[cpu].vpe_id;
+ }
+ asid = asid_cache(cpu);
+
+ do {
+ if (!((asid += ASID_INC) & ASID_MASK) ) {
+ if (cpu_has_vtag_icache)
+ flush_icache_all();
+ /* Traverse all online CPUs (hack requires contigous range) */
+ for (i = 0; i < num_online_cpus(); i++) {
+ /*
+ * We don't need to worry about our own CPU, nor those of
+ * CPUs who don't share our TLB.
+ */
+ if ((i != smp_processor_id()) &&
+ ((smtc_status & SMTC_TLB_SHARED) ||
+ (cpu_data[i].vpe_id == cpu_data[cpu].vpe_id))) {
+ settc(cpu_data[i].tc_id);
+ prevhalt = read_tc_c0_tchalt() & TCHALT_H;
+ if (!prevhalt) {
+ write_tc_c0_tchalt(TCHALT_H);
+ mips_ihb();
+ }
+ tcstat = read_tc_c0_tcstatus();
+ smtc_live_asid[tlb][(tcstat & ASID_MASK)] |= (asiduse)(0x1 << i);
+ if (!prevhalt)
+ write_tc_c0_tchalt(0);
+ }
+ }
+ if (!asid) /* fix version if needed */
+ asid = ASID_FIRST_VERSION;
+ local_flush_tlb_all(); /* start new asid cycle */
+ }
+ } while (smtc_live_asid[tlb][(asid & ASID_MASK)]);
+
+ /*
+ * SMTC shares the TLB within VPEs and possibly across all VPEs.
+ */
+ for (i = 0; i < num_online_cpus(); i++) {
+ if ((smtc_status & SMTC_TLB_SHARED) ||
+ (cpu_data[i].vpe_id == cpu_data[cpu].vpe_id))
+ cpu_context(i, mm) = asid_cache(i) = asid;
+ }
+
+ if (smtc_status & SMTC_TLB_SHARED)
+ evpe(mtflags);
+ else
+ emt(mtflags);
+ local_irq_restore(flags);
+}
+
+/*
+ * Invoked from macros defined in mmu_context.h
+ * which must already have disabled interrupts
+ * and done a DVPE or DMT as appropriate.
+ */
+
+void smtc_flush_tlb_asid(unsigned long asid)
+{
+ int entry;
+ unsigned long ehi;
+
+ entry = read_c0_wired();
+
+ /* Traverse all non-wired entries */
+ while (entry < current_cpu_data.tlbsize) {
+ write_c0_index(entry);
+ ehb();
+ tlb_read();
+ ehb();
+ ehi = read_c0_entryhi();
+ if((ehi & ASID_MASK) == asid) {
+ /*
+ * Invalidate only entries with specified ASID,
+ * makiing sure all entries differ.
+ */
+ write_c0_entryhi(CKSEG0 + (entry << (PAGE_SHIFT + 1)));
+ write_c0_entrylo0(0);
+ write_c0_entrylo1(0);
+ mtc0_tlbw_hazard();
+ tlb_write_indexed();
+ }
+ entry++;
+ }
+ write_c0_index(PARKED_INDEX);
+ tlbw_use_hazard();
+}
+
+/*
+ * Support for single-threading cache flush operations.
+ */
+
+int halt_state_save[NR_CPUS];
+
+/*
+ * To really, really be sure that nothing is being done
+ * by other TCs, halt them all. This code assumes that
+ * a DVPE has already been done, so while their Halted
+ * state is theoretically architecturally unstable, in
+ * practice, it's not going to change while we're looking
+ * at it.
+ */
+
+void smtc_cflush_lockdown(void)
+{
+ int cpu;
+
+ for_each_online_cpu(cpu) {
+ if (cpu != smp_processor_id()) {
+ settc(cpu_data[cpu].tc_id);
+ halt_state_save[cpu] = read_tc_c0_tchalt();
+ write_tc_c0_tchalt(TCHALT_H);
+ }
+ }
+ mips_ihb();
+}
+
+/* It would be cheating to change the cpu_online states during a flush! */
+
+void smtc_cflush_release(void)
+{
+ int cpu;
+
+ /*
+ * Start with a hazard barrier to ensure
+ * that all CACHE ops have played through.
+ */
+ mips_ihb();
+
+ for_each_online_cpu(cpu) {
+ if (cpu != smp_processor_id()) {
+ settc(cpu_data[cpu].tc_id);
+ write_tc_c0_tchalt(halt_state_save[cpu]);
+ }
+ }
+ mips_ihb();
+}
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
index 5e51a2d..13ff4da 100644
--- a/arch/mips/kernel/time.c
+++ b/arch/mips/kernel/time.c
@@ -116,8 +116,7 @@ static void c0_timer_ack(void)
write_c0_compare(expirelo);
/* Check to see if we have missed any timer interrupts. */
- count = read_c0_count();
- if ((count - expirelo) < 0x7fffffff) {
+ while (((count = read_c0_count()) - expirelo) < 0x7fffffff) {
/* missed_timer_count++; */
expirelo = count + cycles_per_jiffy;
write_c0_compare(expirelo);
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 081e6ed..6336fe8 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -280,9 +280,16 @@ static DEFINE_SPINLOCK(die_lock);
NORET_TYPE void ATTRIB_NORET die(const char * str, struct pt_regs * regs)
{
static int die_counter;
+#ifdef CONFIG_MIPS_MT_SMTC
+ unsigned long dvpret = dvpe();
+#endif /* CONFIG_MIPS_MT_SMTC */
console_verbose();
spin_lock_irq(&die_lock);
+ bust_spinlocks(1);
+#ifdef CONFIG_MIPS_MT_SMTC
+ mips_mt_regdump(dvpret);
+#endif /* CONFIG_MIPS_MT_SMTC */
printk("%s[#%d]:\n", str, ++die_counter);
show_registers(regs);
spin_unlock_irq(&die_lock);
@@ -757,6 +764,7 @@ asmlinkage void do_cpu(struct pt_regs *regs)
case 2:
case 3:
+ die_if_kernel("do_cpu invoked from kernel context!", regs);
break;
}
@@ -794,6 +802,36 @@ asmlinkage void do_mcheck(struct pt_regs *regs)
asmlinkage void do_mt(struct pt_regs *regs)
{
+ int subcode;
+
+ die_if_kernel("MIPS MT Thread exception in kernel", regs);
+
+ subcode = (read_vpe_c0_vpecontrol() & VPECONTROL_EXCPT)
+ >> VPECONTROL_EXCPT_SHIFT;
+ switch (subcode) {
+ case 0:
+ printk(KERN_ERR "Thread Underflow\n");
+ break;
+ case 1:
+ printk(KERN_ERR "Thread Overflow\n");
+ break;
+ case 2:
+ printk(KERN_ERR "Invalid YIELD Qualifier\n");
+ break;
+ case 3:
+ printk(KERN_ERR "Gating Storage Exception\n");
+ break;
+ case 4:
+ printk(KERN_ERR "YIELD Scheduler Exception\n");
+ break;
+ case 5:
+ printk(KERN_ERR "Gating Storage Schedulier Exception\n");
+ break;
+ default:
+ printk(KERN_ERR "*** UNKNOWN THREAD EXCEPTION %d ***\n",
+ subcode);
+ break;
+ }
die_if_kernel("MIPS MT Thread exception in kernel", regs);
force_sig(SIGILL, current);
@@ -929,7 +967,15 @@ void ejtag_exception_handler(struct pt_regs *regs)
*/
void nmi_exception_handler(struct pt_regs *regs)
{
+#ifdef CONFIG_MIPS_MT_SMTC
+ unsigned long dvpret = dvpe();
+ bust_spinlocks(1);
+ printk("NMI taken!!!!\n");
+ mips_mt_regdump(dvpret);
+#else
+ bust_spinlocks(1);
printk("NMI taken!!!!\n");
+#endif /* CONFIG_MIPS_MT_SMTC */
die("NMI", regs);
while(1) ;
}
@@ -1007,7 +1053,7 @@ again:
return set;
}
-void mips_srs_free (int set)
+void mips_srs_free(int set)
{
struct shadow_registers *sr = &shadow_registers;
@@ -1027,8 +1073,7 @@ static void *set_vi_srs_handler(int n, void *addr, int srs)
if (addr == NULL) {
handler = (unsigned long) do_default_vi;
srs = 0;
- }
- else
+ } else
handler = (unsigned long) addr;
vi_handlers[n] = (unsigned long) addr;
@@ -1040,8 +1085,7 @@ static void *set_vi_srs_handler(int n, void *addr, int srs)
if (cpu_has_veic) {
if (board_bind_eic_interrupt)
board_bind_eic_interrupt (n, srs);
- }
- else if (cpu_has_vint) {
+ } else if (cpu_has_vint) {
/* SRSMap is only defined if shadow sets are implemented */
if (mips_srs_max() > 1)
change_c0_srsmap (0xf << n*4, srs << n*4);
@@ -1055,6 +1099,15 @@ static void *set_vi_srs_handler(int n, void *addr, int srs)
extern char except_vec_vi, except_vec_vi_lui;
extern char except_vec_vi_ori, except_vec_vi_end;
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * We need to provide the SMTC vectored interrupt handler
+ * not only with the address of the handler, but with the
+ * Status.IM bit to be masked before going there.
+ */
+ extern char except_vec_vi_mori;
+ const int mori_offset = &except_vec_vi_mori - &except_vec_vi;
+#endif /* CONFIG_MIPS_MT_SMTC */
const int handler_len = &except_vec_vi_end - &except_vec_vi;
const int lui_offset = &except_vec_vi_lui - &except_vec_vi;
const int ori_offset = &except_vec_vi_ori - &except_vec_vi;
@@ -1068,6 +1121,12 @@ static void *set_vi_srs_handler(int n, void *addr, int srs)
}
memcpy (b, &except_vec_vi, handler_len);
+#ifdef CONFIG_MIPS_MT_SMTC
+ if (n > 7)
+ printk("Vector index %d exceeds SMTC maximum\n", n);
+ w = (u32 *)(b + mori_offset);
+ *w = (*w & 0xffff0000) | (0x100 << n);
+#endif /* CONFIG_MIPS_MT_SMTC */
w = (u32 *)(b + lui_offset);
*w = (*w & 0xffff0000) | (((u32)handler >> 16) & 0xffff);
w = (u32 *)(b + ori_offset);
@@ -1090,7 +1149,7 @@ static void *set_vi_srs_handler(int n, void *addr, int srs)
return (void *)old_handler;
}
-void *set_vi_handler (int n, void *addr)
+void *set_vi_handler(int n, void *addr)
{
return set_vi_srs_handler(n, addr, 0);
}
@@ -1108,8 +1167,29 @@ extern asmlinkage int _restore_fp_context(struct sigcontext *sc);
extern asmlinkage int fpu_emulator_save_context(struct sigcontext *sc);
extern asmlinkage int fpu_emulator_restore_context(struct sigcontext *sc);
+#ifdef CONFIG_SMP
+static int smp_save_fp_context(struct sigcontext *sc)
+{
+ return cpu_has_fpu
+ ? _save_fp_context(sc)
+ : fpu_emulator_save_context(sc);
+}
+
+static int smp_restore_fp_context(struct sigcontext *sc)
+{
+ return cpu_has_fpu
+ ? _restore_fp_context(sc)
+ : fpu_emulator_restore_context(sc);
+}
+#endif
+
static inline void signal_init(void)
{
+#ifdef CONFIG_SMP
+ /* For now just do the cpu_has_fpu check when the functions are invoked */
+ save_fp_context = smp_save_fp_context;
+ restore_fp_context = smp_restore_fp_context;
+#else
if (cpu_has_fpu) {
save_fp_context = _save_fp_context;
restore_fp_context = _restore_fp_context;
@@ -1117,6 +1197,7 @@ static inline void signal_init(void)
save_fp_context = fpu_emulator_save_context;
restore_fp_context = fpu_emulator_restore_context;
}
+#endif
}
#ifdef CONFIG_MIPS32_COMPAT
@@ -1153,6 +1234,20 @@ void __init per_cpu_trap_init(void)
{
unsigned int cpu = smp_processor_id();
unsigned int status_set = ST0_CU0;
+#ifdef CONFIG_MIPS_MT_SMTC
+ int secondaryTC = 0;
+ int bootTC = (cpu == 0);
+
+ /*
+ * Only do per_cpu_trap_init() for first TC of Each VPE.
+ * Note that this hack assumes that the SMTC init code
+ * assigns TCs consecutively and in ascending order.
+ */
+
+ if (((read_c0_tcbind() & TCBIND_CURTC) != 0) &&
+ ((read_c0_tcbind() & TCBIND_CURVPE) == cpu_data[cpu - 1].vpe_id))
+ secondaryTC = 1;
+#endif /* CONFIG_MIPS_MT_SMTC */
/*
* Disable coprocessors and select 32-bit or 64-bit addressing
@@ -1175,6 +1270,10 @@ void __init per_cpu_trap_init(void)
write_c0_hwrena (0x0000000f); /* Allow rdhwr to all registers */
#endif
+#ifdef CONFIG_MIPS_MT_SMTC
+ if (!secondaryTC) {
+#endif /* CONFIG_MIPS_MT_SMTC */
+
/*
* Interrupt handling.
*/
@@ -1191,6 +1290,9 @@ void __init per_cpu_trap_init(void)
} else
set_c0_cause(CAUSEF_IV);
}
+#ifdef CONFIG_MIPS_MT_SMTC
+ }
+#endif /* CONFIG_MIPS_MT_SMTC */
cpu_data[cpu].asid_cache = ASID_FIRST_VERSION;
TLBMISS_HANDLER_SETUP();
@@ -1200,8 +1302,14 @@ void __init per_cpu_trap_init(void)
BUG_ON(current->mm);
enter_lazy_tlb(&init_mm, current);
- cpu_cache_init();
- tlb_init();
+#ifdef CONFIG_MIPS_MT_SMTC
+ if (bootTC) {
+#endif /* CONFIG_MIPS_MT_SMTC */
+ cpu_cache_init();
+ tlb_init();
+#ifdef CONFIG_MIPS_MT_SMTC
+ }
+#endif /* CONFIG_MIPS_MT_SMTC */
}
/* Install CPU exception handler */
diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
index 2ad0ced..14fa00e 100644
--- a/arch/mips/kernel/vmlinux.lds.S
+++ b/arch/mips/kernel/vmlinux.lds.S
@@ -2,7 +2,7 @@
#include <asm/asm-offsets.h>
#include <asm-generic/vmlinux.lds.h>
-#undef mips /* CPP really sucks for this job */
+#undef mips
#define mips mips
OUTPUT_ARCH(mips)
ENTRY(kernel_entry)
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