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-rw-r--r--arch/microblaze/kernel/process.c79
1 files changed, 71 insertions, 8 deletions
diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c
index 436f26c..00b12c6 100644
--- a/arch/microblaze/kernel/process.c
+++ b/arch/microblaze/kernel/process.c
@@ -18,7 +18,7 @@
void show_regs(struct pt_regs *regs)
{
- printk(KERN_INFO " Registers dump: mode=%X\r\n", regs->kernel_mode);
+ printk(KERN_INFO " Registers dump: mode=%X\r\n", regs->pt_mode);
printk(KERN_INFO " r1=%08lX, r2=%08lX, r3=%08lX, r4=%08lX\n",
regs->r1, regs->r2, regs->r3, regs->r4);
printk(KERN_INFO " r5=%08lX, r6=%08lX, r7=%08lX, r8=%08lX\n",
@@ -37,8 +37,6 @@ void show_regs(struct pt_regs *regs)
regs->r29, regs->r30, regs->r31, regs->pc);
printk(KERN_INFO " msr=%08lX, ear=%08lX, esr=%08lX, fsr=%08lX\n",
regs->msr, regs->ear, regs->esr, regs->fsr);
- while (1)
- ;
}
void (*pm_idle)(void);
@@ -128,9 +126,54 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
else
childregs->r1 = ((unsigned long) ti) + THREAD_SIZE;
+#ifndef CONFIG_MMU
memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
ti->cpu_context.r1 = (unsigned long)childregs;
ti->cpu_context.msr = (unsigned long)childregs->msr;
+#else
+
+ /* if creating a kernel thread then update the current reg (we don't
+ * want to use the parent's value when restoring by POP_STATE) */
+ if (kernel_mode(regs))
+ /* save new current on stack to use POP_STATE */
+ childregs->CURRENT_TASK = (unsigned long)p;
+ /* if returning to user then use the parent's value of this register */
+
+ /* if we're creating a new kernel thread then just zeroing all
+ * the registers. That's OK for a brand new thread.*/
+ /* Pls. note that some of them will be restored in POP_STATE */
+ if (kernel_mode(regs))
+ memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
+ /* if this thread is created for fork/vfork/clone, then we want to
+ * restore all the parent's context */
+ /* in addition to the registers which will be restored by POP_STATE */
+ else {
+ ti->cpu_context = *(struct cpu_context *)regs;
+ childregs->msr |= MSR_UMS;
+ }
+
+ /* FIXME STATE_SAVE_PT_OFFSET; */
+ ti->cpu_context.r1 = (unsigned long)childregs - STATE_SAVE_ARG_SPACE;
+ /* we should consider the fact that childregs is a copy of the parent
+ * regs which were saved immediately after entering the kernel state
+ * before enabling VM. This MSR will be restored in switch_to and
+ * RETURN() and we want to have the right machine state there
+ * specifically this state must have INTs disabled before and enabled
+ * after performing rtbd
+ * compose the right MSR for RETURN(). It will work for switch_to also
+ * excepting for VM and UMS
+ * don't touch UMS , CARRY and cache bits
+ * right now MSR is a copy of parent one */
+ childregs->msr |= MSR_BIP;
+ childregs->msr &= ~MSR_EIP;
+ childregs->msr |= MSR_IE;
+ childregs->msr &= ~MSR_VM;
+ childregs->msr |= MSR_VMS;
+ childregs->msr |= MSR_EE; /* exceptions will be enabled*/
+
+ ti->cpu_context.msr = (childregs->msr|MSR_VM);
+ ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */
+#endif
ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8;
if (clone_flags & CLONE_SETTLS)
@@ -139,6 +182,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
return 0;
}
+#ifndef CONFIG_MMU
/*
* Return saved PC of a blocked thread.
*/
@@ -153,6 +197,7 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
else
return ctx->r14;
}
+#endif
static void kernel_thread_helper(int (*fn)(void *), void *arg)
{
@@ -163,7 +208,6 @@ static void kernel_thread_helper(int (*fn)(void *), void *arg)
int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
struct pt_regs regs;
- int ret;
memset(&regs, 0, sizeof(regs));
/* store them in non-volatile registers */
@@ -171,16 +215,35 @@ int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
regs.r6 = (unsigned long)arg;
local_save_flags(regs.msr);
regs.pc = (unsigned long)kernel_thread_helper;
- regs.kernel_mode = 1;
+ regs.pt_mode = 1;
- ret = do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
+ return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
&regs, 0, NULL, NULL);
-
- return ret;
}
+EXPORT_SYMBOL_GPL(kernel_thread);
unsigned long get_wchan(struct task_struct *p)
{
/* TBD (used by procfs) */
return 0;
}
+
+/* Set up a thread for executing a new program */
+void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
+{
+ set_fs(USER_DS);
+ regs->pc = pc;
+ regs->r1 = usp;
+ regs->pt_mode = 0;
+}
+
+#ifdef CONFIG_MMU
+#include <linux/elfcore.h>
+/*
+ * Set up a thread for executing a new program
+ */
+int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
+{
+ return 0; /* MicroBlaze has no separate FPU registers */
+}
+#endif /* CONFIG_MMU */
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