MIPS: Loongson-3: Add some unaligned instructions emulation

1, Add unaligned gslq, gssq, gslqc1, gssqc1 emulation;
2, Add unaligned gsl{h, w, d}x, gss{h, w, d}x emulation;
3, Add unaligned gslwxc1, gsswxc1, gsldxc1, gssdxc1 emulation.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Pei Huang <huangpei@loongson.cn>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
This commit is contained in:
Huacai Chen 2020-04-24 18:56:46 +08:00 committed by Thomas Bogendoerfer
parent d339cd02b8
commit f83e4f9896
2 changed files with 314 additions and 1 deletions

View File

@ -988,6 +988,30 @@ struct mm16_r5_format { /* Load/store from stack pointer format */
;))))
};
/*
* Loongson-3 overridden COP2 instruction formats (32-bit length)
*/
struct loongson3_lswc2_format { /* Loongson-3 overridden lwc2/swc2 Load/Store format */
__BITFIELD_FIELD(unsigned int opcode : 6,
__BITFIELD_FIELD(unsigned int base : 5,
__BITFIELD_FIELD(unsigned int rt : 5,
__BITFIELD_FIELD(unsigned int fr : 1,
__BITFIELD_FIELD(unsigned int offset : 9,
__BITFIELD_FIELD(unsigned int ls : 1,
__BITFIELD_FIELD(unsigned int rq : 5,
;)))))))
};
struct loongson3_lsdc2_format { /* Loongson-3 overridden ldc2/sdc2 Load/Store format */
__BITFIELD_FIELD(unsigned int opcode : 6,
__BITFIELD_FIELD(unsigned int base : 5,
__BITFIELD_FIELD(unsigned int rt : 5,
__BITFIELD_FIELD(unsigned int index : 5,
__BITFIELD_FIELD(unsigned int offset : 8,
__BITFIELD_FIELD(unsigned int opcode1 : 3,
;))))))
};
/*
* MIPS16e instruction formats (16-bit length)
*/
@ -1088,6 +1112,8 @@ union mips_instruction {
struct mm16_rb_format mm16_rb_format;
struct mm16_r3_format mm16_r3_format;
struct mm16_r5_format mm16_r5_format;
struct loongson3_lswc2_format loongson3_lswc2_format;
struct loongson3_lsdc2_format loongson3_lsdc2_format;
};
union mips16e_instruction {

View File

@ -14,17 +14,29 @@
#include <linux/sched.h>
#include <linux/notifier.h>
#include <linux/ptrace.h>
#include <linux/uaccess.h>
#include <linux/sched/signal.h>
#include <asm/fpu.h>
#include <asm/cop2.h>
#include <asm/inst.h>
#include <asm/branch.h>
#include <asm/current.h>
#include <asm/mipsregs.h>
static int loongson_cu2_call(struct notifier_block *nfb, unsigned long action,
void *data)
{
int fpu_owned;
unsigned int res, fpu_owned;
unsigned long ra, value, value_next;
union mips_instruction insn;
int fr = !test_thread_flag(TIF_32BIT_FPREGS);
struct pt_regs *regs = (struct pt_regs *)data;
void __user *addr = (void __user *)regs->cp0_badvaddr;
unsigned int __user *pc = (unsigned int __user *)exception_epc(regs);
ra = regs->regs[31];
__get_user(insn.word, pc);
switch (action) {
case CU2_EXCEPTION:
@ -49,9 +61,284 @@ static int loongson_cu2_call(struct notifier_block *nfb, unsigned long action,
preempt_enable();
return NOTIFY_STOP; /* Don't call default notifier */
case CU2_LWC2_OP:
if (insn.loongson3_lswc2_format.ls == 0)
goto sigbus;
if (insn.loongson3_lswc2_format.fr == 0) { /* gslq */
if (!access_ok(addr, 16))
goto sigbus;
LoadDW(addr, value, res);
if (res)
goto fault;
LoadDW(addr + 8, value_next, res);
if (res)
goto fault;
regs->regs[insn.loongson3_lswc2_format.rt] = value;
regs->regs[insn.loongson3_lswc2_format.rq] = value_next;
compute_return_epc(regs);
} else { /* gslqc1 */
if (!access_ok(addr, 16))
goto sigbus;
lose_fpu(1);
LoadDW(addr, value, res);
if (res)
goto fault;
LoadDW(addr + 8, value_next, res);
if (res)
goto fault;
set_fpr64(current->thread.fpu.fpr,
insn.loongson3_lswc2_format.rt, value);
set_fpr64(current->thread.fpu.fpr,
insn.loongson3_lswc2_format.rq, value_next);
compute_return_epc(regs);
own_fpu(1);
}
return NOTIFY_STOP; /* Don't call default notifier */
case CU2_SWC2_OP:
if (insn.loongson3_lswc2_format.ls == 0)
goto sigbus;
if (insn.loongson3_lswc2_format.fr == 0) { /* gssq */
if (!access_ok(addr, 16))
goto sigbus;
/* write upper 8 bytes first */
value_next = regs->regs[insn.loongson3_lswc2_format.rq];
StoreDW(addr + 8, value_next, res);
if (res)
goto fault;
value = regs->regs[insn.loongson3_lswc2_format.rt];
StoreDW(addr, value, res);
if (res)
goto fault;
compute_return_epc(regs);
} else { /* gssqc1 */
if (!access_ok(addr, 16))
goto sigbus;
lose_fpu(1);
value_next = get_fpr64(current->thread.fpu.fpr,
insn.loongson3_lswc2_format.rq);
StoreDW(addr + 8, value_next, res);
if (res)
goto fault;
value = get_fpr64(current->thread.fpu.fpr,
insn.loongson3_lswc2_format.rt);
StoreDW(addr, value, res);
if (res)
goto fault;
compute_return_epc(regs);
own_fpu(1);
}
return NOTIFY_STOP; /* Don't call default notifier */
case CU2_LDC2_OP:
switch (insn.loongson3_lsdc2_format.opcode1) {
/*
* Loongson-3 overridden ldc2 instructions.
* opcode1 instruction
* 0x1 gslhx: load 2 bytes to GPR
* 0x2 gslwx: load 4 bytes to GPR
* 0x3 gsldx: load 8 bytes to GPR
* 0x6 gslwxc1: load 4 bytes to FPR
* 0x7 gsldxc1: load 8 bytes to FPR
*/
case 0x1:
if (!access_ok(addr, 2))
goto sigbus;
LoadHW(addr, value, res);
if (res)
goto fault;
compute_return_epc(regs);
regs->regs[insn.loongson3_lsdc2_format.rt] = value;
break;
case 0x2:
if (!access_ok(addr, 4))
goto sigbus;
LoadW(addr, value, res);
if (res)
goto fault;
compute_return_epc(regs);
regs->regs[insn.loongson3_lsdc2_format.rt] = value;
break;
case 0x3:
if (!access_ok(addr, 8))
goto sigbus;
LoadDW(addr, value, res);
if (res)
goto fault;
compute_return_epc(regs);
regs->regs[insn.loongson3_lsdc2_format.rt] = value;
break;
case 0x6:
die_if_kernel("Unaligned FP access in kernel code", regs);
BUG_ON(!used_math());
if (!access_ok(addr, 4))
goto sigbus;
lose_fpu(1);
LoadW(addr, value, res);
if (res)
goto fault;
set_fpr64(current->thread.fpu.fpr,
insn.loongson3_lsdc2_format.rt, value);
compute_return_epc(regs);
own_fpu(1);
break;
case 0x7:
die_if_kernel("Unaligned FP access in kernel code", regs);
BUG_ON(!used_math());
if (!access_ok(addr, 8))
goto sigbus;
lose_fpu(1);
LoadDW(addr, value, res);
if (res)
goto fault;
set_fpr64(current->thread.fpu.fpr,
insn.loongson3_lsdc2_format.rt, value);
compute_return_epc(regs);
own_fpu(1);
break;
}
return NOTIFY_STOP; /* Don't call default notifier */
case CU2_SDC2_OP:
switch (insn.loongson3_lsdc2_format.opcode1) {
/*
* Loongson-3 overridden sdc2 instructions.
* opcode1 instruction
* 0x1 gsshx: store 2 bytes from GPR
* 0x2 gsswx: store 4 bytes from GPR
* 0x3 gssdx: store 8 bytes from GPR
* 0x6 gsswxc1: store 4 bytes from FPR
* 0x7 gssdxc1: store 8 bytes from FPR
*/
case 0x1:
if (!access_ok(addr, 2))
goto sigbus;
compute_return_epc(regs);
value = regs->regs[insn.loongson3_lsdc2_format.rt];
StoreHW(addr, value, res);
if (res)
goto fault;
break;
case 0x2:
if (!access_ok(addr, 4))
goto sigbus;
compute_return_epc(regs);
value = regs->regs[insn.loongson3_lsdc2_format.rt];
StoreW(addr, value, res);
if (res)
goto fault;
break;
case 0x3:
if (!access_ok(addr, 8))
goto sigbus;
compute_return_epc(regs);
value = regs->regs[insn.loongson3_lsdc2_format.rt];
StoreDW(addr, value, res);
if (res)
goto fault;
break;
case 0x6:
die_if_kernel("Unaligned FP access in kernel code", regs);
BUG_ON(!used_math());
if (!access_ok(addr, 4))
goto sigbus;
lose_fpu(1);
value = get_fpr64(current->thread.fpu.fpr,
insn.loongson3_lsdc2_format.rt);
StoreW(addr, value, res);
if (res)
goto fault;
compute_return_epc(regs);
own_fpu(1);
break;
case 0x7:
die_if_kernel("Unaligned FP access in kernel code", regs);
BUG_ON(!used_math());
if (!access_ok(addr, 8))
goto sigbus;
lose_fpu(1);
value = get_fpr64(current->thread.fpu.fpr,
insn.loongson3_lsdc2_format.rt);
StoreDW(addr, value, res);
if (res)
goto fault;
compute_return_epc(regs);
own_fpu(1);
break;
}
return NOTIFY_STOP; /* Don't call default notifier */
}
return NOTIFY_OK; /* Let default notifier send signals */
fault:
/* roll back jump/branch */
regs->regs[31] = ra;
regs->cp0_epc = (unsigned long)pc;
/* Did we have an exception handler installed? */
if (fixup_exception(regs))
return NOTIFY_STOP; /* Don't call default notifier */
die_if_kernel("Unhandled kernel unaligned access", regs);
force_sig(SIGSEGV);
return NOTIFY_STOP; /* Don't call default notifier */
sigbus:
die_if_kernel("Unhandled kernel unaligned access", regs);
force_sig(SIGBUS);
return NOTIFY_STOP; /* Don't call default notifier */
}
static int __init loongson_cu2_setup(void)