microblaze_mmu_v2: Update process creation for MMU

Signed-off-by: Michal Simek <monstr@monstr.eu>
This commit is contained in:
Michal Simek
2009-05-26 16:30:18 +02:00
parent 1f84e1ea0e
commit 5233806dfe
4 changed files with 181 additions and 13 deletions

View File

@@ -126,9 +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)
@@ -137,6 +182,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
return 0;
}
#ifndef CONFIG_MMU
/*
* Return saved PC of a blocked thread.
*/
@@ -151,6 +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)
{
@@ -189,3 +236,14 @@ void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
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 */