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Diffstat (limited to 'arch/cris/arch-v32/kernel/irq.c')
-rw-r--r--arch/cris/arch-v32/kernel/irq.c413
1 files changed, 413 insertions, 0 deletions
diff --git a/arch/cris/arch-v32/kernel/irq.c b/arch/cris/arch-v32/kernel/irq.c
new file mode 100644
index 0000000..c78cc26
--- /dev/null
+++ b/arch/cris/arch-v32/kernel/irq.c
@@ -0,0 +1,413 @@
+/*
+ * Copyright (C) 2003, Axis Communications AB.
+ */
+
+#include <asm/irq.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/smp.h>
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/profile.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/threads.h>
+#include <linux/spinlock.h>
+#include <linux/kernel_stat.h>
+#include <asm/arch/hwregs/reg_map.h>
+#include <asm/arch/hwregs/reg_rdwr.h>
+#include <asm/arch/hwregs/intr_vect.h>
+#include <asm/arch/hwregs/intr_vect_defs.h>
+
+#define CPU_FIXED -1
+
+/* IRQ masks (refer to comment for crisv32_do_multiple) */
+#define TIMER_MASK (1 << (TIMER_INTR_VECT - FIRST_IRQ))
+#ifdef CONFIG_ETRAX_KGDB
+#if defined(CONFIG_ETRAX_KGDB_PORT0)
+#define IGNOREMASK (1 << (SER0_INTR_VECT - FIRST_IRQ))
+#elif defined(CONFIG_ETRAX_KGDB_PORT1)
+#define IGNOREMASK (1 << (SER1_INTR_VECT - FIRST_IRQ))
+#elif defined(CONFIG_ETRAX_KGB_PORT2)
+#define IGNOREMASK (1 << (SER2_INTR_VECT - FIRST_IRQ))
+#elif defined(CONFIG_ETRAX_KGDB_PORT3)
+#define IGNOREMASK (1 << (SER3_INTR_VECT - FIRST_IRQ))
+#endif
+#endif
+
+DEFINE_SPINLOCK(irq_lock);
+
+struct cris_irq_allocation
+{
+ int cpu; /* The CPU to which the IRQ is currently allocated. */
+ cpumask_t mask; /* The CPUs to which the IRQ may be allocated. */
+};
+
+struct cris_irq_allocation irq_allocations[NR_IRQS] =
+ {[0 ... NR_IRQS - 1] = {0, CPU_MASK_ALL}};
+
+static unsigned long irq_regs[NR_CPUS] =
+{
+ regi_irq,
+#ifdef CONFIG_SMP
+ regi_irq2,
+#endif
+};
+
+unsigned long cpu_irq_counters[NR_CPUS];
+unsigned long irq_counters[NR_REAL_IRQS];
+
+/* From irq.c. */
+extern void weird_irq(void);
+
+/* From entry.S. */
+extern void system_call(void);
+extern void nmi_interrupt(void);
+extern void multiple_interrupt(void);
+extern void gdb_handle_exception(void);
+extern void i_mmu_refill(void);
+extern void i_mmu_invalid(void);
+extern void i_mmu_access(void);
+extern void i_mmu_execute(void);
+extern void d_mmu_refill(void);
+extern void d_mmu_invalid(void);
+extern void d_mmu_access(void);
+extern void d_mmu_write(void);
+
+/* From kgdb.c. */
+extern void kgdb_init(void);
+extern void breakpoint(void);
+
+/*
+ * Build the IRQ handler stubs using macros from irq.h. First argument is the
+ * IRQ number, the second argument is the corresponding bit in
+ * intr_rw_vect_mask found in asm/arch/hwregs/intr_vect_defs.h.
+ */
+BUILD_IRQ(0x31, (1 << 0)) /* memarb */
+BUILD_IRQ(0x32, (1 << 1)) /* gen_io */
+BUILD_IRQ(0x33, (1 << 2)) /* iop0 */
+BUILD_IRQ(0x34, (1 << 3)) /* iop1 */
+BUILD_IRQ(0x35, (1 << 4)) /* iop2 */
+BUILD_IRQ(0x36, (1 << 5)) /* iop3 */
+BUILD_IRQ(0x37, (1 << 6)) /* dma0 */
+BUILD_IRQ(0x38, (1 << 7)) /* dma1 */
+BUILD_IRQ(0x39, (1 << 8)) /* dma2 */
+BUILD_IRQ(0x3a, (1 << 9)) /* dma3 */
+BUILD_IRQ(0x3b, (1 << 10)) /* dma4 */
+BUILD_IRQ(0x3c, (1 << 11)) /* dma5 */
+BUILD_IRQ(0x3d, (1 << 12)) /* dma6 */
+BUILD_IRQ(0x3e, (1 << 13)) /* dma7 */
+BUILD_IRQ(0x3f, (1 << 14)) /* dma8 */
+BUILD_IRQ(0x40, (1 << 15)) /* dma9 */
+BUILD_IRQ(0x41, (1 << 16)) /* ata */
+BUILD_IRQ(0x42, (1 << 17)) /* sser0 */
+BUILD_IRQ(0x43, (1 << 18)) /* sser1 */
+BUILD_IRQ(0x44, (1 << 19)) /* ser0 */
+BUILD_IRQ(0x45, (1 << 20)) /* ser1 */
+BUILD_IRQ(0x46, (1 << 21)) /* ser2 */
+BUILD_IRQ(0x47, (1 << 22)) /* ser3 */
+BUILD_IRQ(0x48, (1 << 23))
+BUILD_IRQ(0x49, (1 << 24)) /* eth0 */
+BUILD_IRQ(0x4a, (1 << 25)) /* eth1 */
+BUILD_TIMER_IRQ(0x4b, (1 << 26))/* timer */
+BUILD_IRQ(0x4c, (1 << 27)) /* bif_arb */
+BUILD_IRQ(0x4d, (1 << 28)) /* bif_dma */
+BUILD_IRQ(0x4e, (1 << 29)) /* ext */
+BUILD_IRQ(0x4f, (1 << 29)) /* ipi */
+
+/* Pointers to the low-level handlers. */
+static void (*interrupt[NR_IRQS])(void) = {
+ IRQ0x31_interrupt, IRQ0x32_interrupt, IRQ0x33_interrupt,
+ IRQ0x34_interrupt, IRQ0x35_interrupt, IRQ0x36_interrupt,
+ IRQ0x37_interrupt, IRQ0x38_interrupt, IRQ0x39_interrupt,
+ IRQ0x3a_interrupt, IRQ0x3b_interrupt, IRQ0x3c_interrupt,
+ IRQ0x3d_interrupt, IRQ0x3e_interrupt, IRQ0x3f_interrupt,
+ IRQ0x40_interrupt, IRQ0x41_interrupt, IRQ0x42_interrupt,
+ IRQ0x43_interrupt, IRQ0x44_interrupt, IRQ0x45_interrupt,
+ IRQ0x46_interrupt, IRQ0x47_interrupt, IRQ0x48_interrupt,
+ IRQ0x49_interrupt, IRQ0x4a_interrupt, IRQ0x4b_interrupt,
+ IRQ0x4c_interrupt, IRQ0x4d_interrupt, IRQ0x4e_interrupt,
+ IRQ0x4f_interrupt
+};
+
+void
+block_irq(int irq, int cpu)
+{
+ int intr_mask;
+ unsigned long flags;
+
+ spin_lock_irqsave(&irq_lock, flags);
+ intr_mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
+
+ /* Remember; 1 let thru, 0 block. */
+ intr_mask &= ~(1 << (irq - FIRST_IRQ));
+
+ REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, intr_mask);
+ spin_unlock_irqrestore(&irq_lock, flags);
+}
+
+void
+unblock_irq(int irq, int cpu)
+{
+ int intr_mask;
+ unsigned long flags;
+
+ spin_lock_irqsave(&irq_lock, flags);
+ intr_mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
+
+ /* Remember; 1 let thru, 0 block. */
+ intr_mask |= (1 << (irq - FIRST_IRQ));
+
+ REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, intr_mask);
+ spin_unlock_irqrestore(&irq_lock, flags);
+}
+
+/* Find out which CPU the irq should be allocated to. */
+static int irq_cpu(int irq)
+{
+ int cpu;
+ unsigned long flags;
+
+ spin_lock_irqsave(&irq_lock, flags);
+ cpu = irq_allocations[irq - FIRST_IRQ].cpu;
+
+ /* Fixed interrupts stay on the local CPU. */
+ if (cpu == CPU_FIXED)
+ {
+ spin_unlock_irqrestore(&irq_lock, flags);
+ return smp_processor_id();
+ }
+
+
+ /* Let the interrupt stay if possible */
+ if (cpu_isset(cpu, irq_allocations[irq - FIRST_IRQ].mask))
+ goto out;
+
+ /* IRQ must be moved to another CPU. */
+ cpu = first_cpu(irq_allocations[irq - FIRST_IRQ].mask);
+ irq_allocations[irq - FIRST_IRQ].cpu = cpu;
+out:
+ spin_unlock_irqrestore(&irq_lock, flags);
+ return cpu;
+}
+
+void
+mask_irq(int irq)
+{
+ int cpu;
+
+ for (cpu = 0; cpu < NR_CPUS; cpu++)
+ block_irq(irq, cpu);
+}
+
+void
+unmask_irq(int irq)
+{
+ unblock_irq(irq, irq_cpu(irq));
+}
+
+
+static unsigned int startup_crisv32_irq(unsigned int irq)
+{
+ unmask_irq(irq);
+ return 0;
+}
+
+static void shutdown_crisv32_irq(unsigned int irq)
+{
+ mask_irq(irq);
+}
+
+static void enable_crisv32_irq(unsigned int irq)
+{
+ unmask_irq(irq);
+}
+
+static void disable_crisv32_irq(unsigned int irq)
+{
+ mask_irq(irq);
+}
+
+static void ack_crisv32_irq(unsigned int irq)
+{
+}
+
+static void end_crisv32_irq(unsigned int irq)
+{
+}
+
+void set_affinity_crisv32_irq(unsigned int irq, cpumask_t dest)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&irq_lock, flags);
+ irq_allocations[irq - FIRST_IRQ].mask = dest;
+ spin_unlock_irqrestore(&irq_lock, flags);
+}
+
+static struct hw_interrupt_type crisv32_irq_type = {
+ .typename = "CRISv32",
+ .startup = startup_crisv32_irq,
+ .shutdown = shutdown_crisv32_irq,
+ .enable = enable_crisv32_irq,
+ .disable = disable_crisv32_irq,
+ .ack = ack_crisv32_irq,
+ .end = end_crisv32_irq,
+ .set_affinity = set_affinity_crisv32_irq
+};
+
+void
+set_exception_vector(int n, irqvectptr addr)
+{
+ etrax_irv->v[n] = (irqvectptr) addr;
+}
+
+extern void do_IRQ(int irq, struct pt_regs * regs);
+
+void
+crisv32_do_IRQ(int irq, int block, struct pt_regs* regs)
+{
+ /* Interrupts that may not be moved to another CPU and
+ * are SA_INTERRUPT may skip blocking. This is currently
+ * only valid for the timer IRQ and the IPI and is used
+ * for the timer interrupt to avoid watchdog starvation.
+ */
+ if (!block) {
+ do_IRQ(irq, regs);
+ return;
+ }
+
+ block_irq(irq, smp_processor_id());
+ do_IRQ(irq, regs);
+
+ unblock_irq(irq, irq_cpu(irq));
+}
+
+/* If multiple interrupts occur simultaneously we get a multiple
+ * interrupt from the CPU and software has to sort out which
+ * interrupts that happened. There are two special cases here:
+ *
+ * 1. Timer interrupts may never be blocked because of the
+ * watchdog (refer to comment in include/asr/arch/irq.h)
+ * 2. GDB serial port IRQs are unhandled here and will be handled
+ * as a single IRQ when it strikes again because the GDB
+ * stubb wants to save the registers in its own fashion.
+ */
+void
+crisv32_do_multiple(struct pt_regs* regs)
+{
+ int cpu;
+ int mask;
+ int masked;
+ int bit;
+
+ cpu = smp_processor_id();
+
+ /* An extra irq_enter here to prevent softIRQs to run after
+ * each do_IRQ. This will decrease the interrupt latency.
+ */
+ irq_enter();
+
+ /* Get which IRQs that happend. */
+ masked = REG_RD_INT(intr_vect, irq_regs[cpu], r_masked_vect);
+
+ /* Calculate new IRQ mask with these IRQs disabled. */
+ mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
+ mask &= ~masked;
+
+ /* Timer IRQ is never masked */
+ if (masked & TIMER_MASK)
+ mask |= TIMER_MASK;
+
+ /* Block all the IRQs */
+ REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, mask);
+
+ /* Check for timer IRQ and handle it special. */
+ if (masked & TIMER_MASK) {
+ masked &= ~TIMER_MASK;
+ do_IRQ(TIMER_INTR_VECT, regs);
+ }
+
+#ifdef IGNORE_MASK
+ /* Remove IRQs that can't be handled as multiple. */
+ masked &= ~IGNORE_MASK;
+#endif
+
+ /* Handle the rest of the IRQs. */
+ for (bit = 0; bit < 32; bit++)
+ {
+ if (masked & (1 << bit))
+ do_IRQ(bit + FIRST_IRQ, regs);
+ }
+
+ /* Unblock all the IRQs. */
+ mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
+ mask |= masked;
+ REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, mask);
+
+ /* This irq_exit() will trigger the soft IRQs. */
+ irq_exit();
+}
+
+/*
+ * This is called by start_kernel. It fixes the IRQ masks and setup the
+ * interrupt vector table to point to bad_interrupt pointers.
+ */
+void __init
+init_IRQ(void)
+{
+ int i;
+ int j;
+ reg_intr_vect_rw_mask vect_mask = {0};
+
+ /* Clear all interrupts masks. */
+ REG_WR(intr_vect, regi_irq, rw_mask, vect_mask);
+
+ for (i = 0; i < 256; i++)
+ etrax_irv->v[i] = weird_irq;
+
+ /* Point all IRQ's to bad handlers. */
+ for (i = FIRST_IRQ, j = 0; j < NR_IRQS; i++, j++) {
+ irq_desc[j].handler = &crisv32_irq_type;
+ set_exception_vector(i, interrupt[j]);
+ }
+
+ /* Mark Timer and IPI IRQs as CPU local */
+ irq_allocations[TIMER_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
+ irq_desc[TIMER_INTR_VECT].status |= IRQ_PER_CPU;
+ irq_allocations[IPI_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
+ irq_desc[IPI_INTR_VECT].status |= IRQ_PER_CPU;
+
+ set_exception_vector(0x00, nmi_interrupt);
+ set_exception_vector(0x30, multiple_interrupt);
+
+ /* Set up handler for various MMU bus faults. */
+ set_exception_vector(0x04, i_mmu_refill);
+ set_exception_vector(0x05, i_mmu_invalid);
+ set_exception_vector(0x06, i_mmu_access);
+ set_exception_vector(0x07, i_mmu_execute);
+ set_exception_vector(0x08, d_mmu_refill);
+ set_exception_vector(0x09, d_mmu_invalid);
+ set_exception_vector(0x0a, d_mmu_access);
+ set_exception_vector(0x0b, d_mmu_write);
+
+ /* The system-call trap is reached by "break 13". */
+ set_exception_vector(0x1d, system_call);
+
+ /* Exception handlers for debugging, both user-mode and kernel-mode. */
+
+ /* Break 8. */
+ set_exception_vector(0x18, gdb_handle_exception);
+ /* Hardware single step. */
+ set_exception_vector(0x3, gdb_handle_exception);
+ /* Hardware breakpoint. */
+ set_exception_vector(0xc, gdb_handle_exception);
+
+#ifdef CONFIG_ETRAX_KGDB
+ kgdb_init();
+ /* Everything is set up; now trap the kernel. */
+ breakpoint();
+#endif
+}
+
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