1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
147 lines
3.5 KiB
C
147 lines
3.5 KiB
C
/*
|
|
* Software emulation of some PPC instructions for the 8xx core.
|
|
*
|
|
* Copyright (C) 1998 Dan Malek (dmalek@jlc.net)
|
|
*
|
|
* Software floating emuation for the MPC8xx processor. I did this mostly
|
|
* because it was easier than trying to get the libraries compiled for
|
|
* software floating point. The goal is still to get the libraries done,
|
|
* but I lost patience and needed some hacks to at least get init and
|
|
* shells running. The first problem is the setjmp/longjmp that save
|
|
* and restore the floating point registers.
|
|
*
|
|
* For this emulation, our working registers are found on the register
|
|
* save area.
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/unistd.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/user.h>
|
|
#include <linux/a.out.h>
|
|
#include <linux/interrupt.h>
|
|
|
|
#include <asm/pgtable.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/system.h>
|
|
#include <asm/io.h>
|
|
|
|
extern void
|
|
print_8xx_pte(struct mm_struct *mm, unsigned long addr);
|
|
extern int
|
|
get_8xx_pte(struct mm_struct *mm, unsigned long addr);
|
|
|
|
/* Eventually we may need a look-up table, but this works for now.
|
|
*/
|
|
#define LFS 48
|
|
#define LFD 50
|
|
#define LFDU 51
|
|
#define STFD 54
|
|
#define STFDU 55
|
|
#define FMR 63
|
|
|
|
/*
|
|
* We return 0 on success, 1 on unimplemented instruction, and EFAULT
|
|
* if a load/store faulted.
|
|
*/
|
|
int
|
|
Soft_emulate_8xx(struct pt_regs *regs)
|
|
{
|
|
uint inst, instword;
|
|
uint flreg, idxreg, disp;
|
|
uint retval;
|
|
signed short sdisp;
|
|
uint *ea, *ip;
|
|
|
|
retval = 0;
|
|
|
|
instword = *((uint *)regs->nip);
|
|
inst = instword >> 26;
|
|
|
|
flreg = (instword >> 21) & 0x1f;
|
|
idxreg = (instword >> 16) & 0x1f;
|
|
disp = instword & 0xffff;
|
|
|
|
ea = (uint *)(regs->gpr[idxreg] + disp);
|
|
ip = (uint *)¤t->thread.fpr[flreg];
|
|
|
|
switch ( inst )
|
|
{
|
|
case LFD:
|
|
/* this is a 16 bit quantity that is sign extended
|
|
* so use a signed short here -- Cort
|
|
*/
|
|
sdisp = (instword & 0xffff);
|
|
ea = (uint *)(regs->gpr[idxreg] + sdisp);
|
|
if (copy_from_user(ip, ea, sizeof(double)))
|
|
retval = -EFAULT;
|
|
break;
|
|
|
|
case LFDU:
|
|
if (copy_from_user(ip, ea, sizeof(double)))
|
|
retval = -EFAULT;
|
|
else
|
|
regs->gpr[idxreg] = (uint)ea;
|
|
break;
|
|
case LFS:
|
|
sdisp = (instword & 0xffff);
|
|
ea = (uint *)(regs->gpr[idxreg] + sdisp);
|
|
if (copy_from_user(ip, ea, sizeof(float)))
|
|
retval = -EFAULT;
|
|
break;
|
|
case STFD:
|
|
/* this is a 16 bit quantity that is sign extended
|
|
* so use a signed short here -- Cort
|
|
*/
|
|
sdisp = (instword & 0xffff);
|
|
ea = (uint *)(regs->gpr[idxreg] + sdisp);
|
|
if (copy_to_user(ea, ip, sizeof(double)))
|
|
retval = -EFAULT;
|
|
break;
|
|
|
|
case STFDU:
|
|
if (copy_to_user(ea, ip, sizeof(double)))
|
|
retval = -EFAULT;
|
|
else
|
|
regs->gpr[idxreg] = (uint)ea;
|
|
break;
|
|
case FMR:
|
|
/* assume this is a fp move -- Cort */
|
|
memcpy( ip, ¤t->thread.fpr[(instword>>11)&0x1f],
|
|
sizeof(double) );
|
|
break;
|
|
default:
|
|
retval = 1;
|
|
printk("Bad emulation %s/%d\n"
|
|
" NIP: %08lx instruction: %08x opcode: %x "
|
|
"A: %x B: %x C: %x code: %x rc: %x\n",
|
|
current->comm,current->pid,
|
|
regs->nip,
|
|
instword,inst,
|
|
(instword>>16)&0x1f,
|
|
(instword>>11)&0x1f,
|
|
(instword>>6)&0x1f,
|
|
(instword>>1)&0x3ff,
|
|
instword&1);
|
|
{
|
|
int pa;
|
|
print_8xx_pte(current->mm,regs->nip);
|
|
pa = get_8xx_pte(current->mm,regs->nip) & PAGE_MASK;
|
|
pa |= (regs->nip & ~PAGE_MASK);
|
|
pa = (unsigned long)__va(pa);
|
|
printk("Kernel VA for NIP %x ", pa);
|
|
print_8xx_pte(current->mm,pa);
|
|
}
|
|
|
|
}
|
|
|
|
if (retval == 0)
|
|
regs->nip += 4;
|
|
return(retval);
|
|
}
|
|
|