mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 08:25:12 +07:00
f03c4866d3
Quite a bit of fallout all over the place, nothing terribly exciting. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
430 lines
12 KiB
C
430 lines
12 KiB
C
/*
|
|
* Save/restore floating point context for signal handlers.
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
|
|
* Copyright (C) 2006 ST Microelectronics Ltd. (denorm support)
|
|
*
|
|
* FIXME! These routines have not been tested for big endian case.
|
|
*/
|
|
#include <linux/sched.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/io.h>
|
|
#include <cpu/fpu.h>
|
|
#include <asm/processor.h>
|
|
#include <asm/fpu.h>
|
|
#include <asm/traps.h>
|
|
|
|
/* The PR (precision) bit in the FP Status Register must be clear when
|
|
* an frchg instruction is executed, otherwise the instruction is undefined.
|
|
* Executing frchg with PR set causes a trap on some SH4 implementations.
|
|
*/
|
|
|
|
#define FPSCR_RCHG 0x00000000
|
|
extern unsigned long long float64_div(unsigned long long a,
|
|
unsigned long long b);
|
|
extern unsigned long int float32_div(unsigned long int a, unsigned long int b);
|
|
extern unsigned long long float64_mul(unsigned long long a,
|
|
unsigned long long b);
|
|
extern unsigned long int float32_mul(unsigned long int a, unsigned long int b);
|
|
extern unsigned long long float64_add(unsigned long long a,
|
|
unsigned long long b);
|
|
extern unsigned long int float32_add(unsigned long int a, unsigned long int b);
|
|
extern unsigned long long float64_sub(unsigned long long a,
|
|
unsigned long long b);
|
|
extern unsigned long int float32_sub(unsigned long int a, unsigned long int b);
|
|
extern unsigned long int float64_to_float32(unsigned long long a);
|
|
static unsigned int fpu_exception_flags;
|
|
|
|
/*
|
|
* Save FPU registers onto task structure.
|
|
*/
|
|
void save_fpu(struct task_struct *tsk)
|
|
{
|
|
unsigned long dummy;
|
|
|
|
enable_fpu();
|
|
asm volatile ("sts.l fpul, @-%0\n\t"
|
|
"sts.l fpscr, @-%0\n\t"
|
|
"lds %2, fpscr\n\t"
|
|
"frchg\n\t"
|
|
"fmov.s fr15, @-%0\n\t"
|
|
"fmov.s fr14, @-%0\n\t"
|
|
"fmov.s fr13, @-%0\n\t"
|
|
"fmov.s fr12, @-%0\n\t"
|
|
"fmov.s fr11, @-%0\n\t"
|
|
"fmov.s fr10, @-%0\n\t"
|
|
"fmov.s fr9, @-%0\n\t"
|
|
"fmov.s fr8, @-%0\n\t"
|
|
"fmov.s fr7, @-%0\n\t"
|
|
"fmov.s fr6, @-%0\n\t"
|
|
"fmov.s fr5, @-%0\n\t"
|
|
"fmov.s fr4, @-%0\n\t"
|
|
"fmov.s fr3, @-%0\n\t"
|
|
"fmov.s fr2, @-%0\n\t"
|
|
"fmov.s fr1, @-%0\n\t"
|
|
"fmov.s fr0, @-%0\n\t"
|
|
"frchg\n\t"
|
|
"fmov.s fr15, @-%0\n\t"
|
|
"fmov.s fr14, @-%0\n\t"
|
|
"fmov.s fr13, @-%0\n\t"
|
|
"fmov.s fr12, @-%0\n\t"
|
|
"fmov.s fr11, @-%0\n\t"
|
|
"fmov.s fr10, @-%0\n\t"
|
|
"fmov.s fr9, @-%0\n\t"
|
|
"fmov.s fr8, @-%0\n\t"
|
|
"fmov.s fr7, @-%0\n\t"
|
|
"fmov.s fr6, @-%0\n\t"
|
|
"fmov.s fr5, @-%0\n\t"
|
|
"fmov.s fr4, @-%0\n\t"
|
|
"fmov.s fr3, @-%0\n\t"
|
|
"fmov.s fr2, @-%0\n\t"
|
|
"fmov.s fr1, @-%0\n\t"
|
|
"fmov.s fr0, @-%0\n\t"
|
|
"lds %3, fpscr\n\t":"=r" (dummy)
|
|
:"0"((char *)(&tsk->thread.xstate->hardfpu.status)),
|
|
"r"(FPSCR_RCHG), "r"(FPSCR_INIT)
|
|
:"memory");
|
|
|
|
disable_fpu();
|
|
}
|
|
|
|
void restore_fpu(struct task_struct *tsk)
|
|
{
|
|
unsigned long dummy;
|
|
|
|
enable_fpu();
|
|
asm volatile ("lds %2, fpscr\n\t"
|
|
"fmov.s @%0+, fr0\n\t"
|
|
"fmov.s @%0+, fr1\n\t"
|
|
"fmov.s @%0+, fr2\n\t"
|
|
"fmov.s @%0+, fr3\n\t"
|
|
"fmov.s @%0+, fr4\n\t"
|
|
"fmov.s @%0+, fr5\n\t"
|
|
"fmov.s @%0+, fr6\n\t"
|
|
"fmov.s @%0+, fr7\n\t"
|
|
"fmov.s @%0+, fr8\n\t"
|
|
"fmov.s @%0+, fr9\n\t"
|
|
"fmov.s @%0+, fr10\n\t"
|
|
"fmov.s @%0+, fr11\n\t"
|
|
"fmov.s @%0+, fr12\n\t"
|
|
"fmov.s @%0+, fr13\n\t"
|
|
"fmov.s @%0+, fr14\n\t"
|
|
"fmov.s @%0+, fr15\n\t"
|
|
"frchg\n\t"
|
|
"fmov.s @%0+, fr0\n\t"
|
|
"fmov.s @%0+, fr1\n\t"
|
|
"fmov.s @%0+, fr2\n\t"
|
|
"fmov.s @%0+, fr3\n\t"
|
|
"fmov.s @%0+, fr4\n\t"
|
|
"fmov.s @%0+, fr5\n\t"
|
|
"fmov.s @%0+, fr6\n\t"
|
|
"fmov.s @%0+, fr7\n\t"
|
|
"fmov.s @%0+, fr8\n\t"
|
|
"fmov.s @%0+, fr9\n\t"
|
|
"fmov.s @%0+, fr10\n\t"
|
|
"fmov.s @%0+, fr11\n\t"
|
|
"fmov.s @%0+, fr12\n\t"
|
|
"fmov.s @%0+, fr13\n\t"
|
|
"fmov.s @%0+, fr14\n\t"
|
|
"fmov.s @%0+, fr15\n\t"
|
|
"frchg\n\t"
|
|
"lds.l @%0+, fpscr\n\t"
|
|
"lds.l @%0+, fpul\n\t"
|
|
:"=r" (dummy)
|
|
:"0" (tsk->thread.xstate), "r" (FPSCR_RCHG)
|
|
:"memory");
|
|
disable_fpu();
|
|
}
|
|
|
|
/**
|
|
* denormal_to_double - Given denormalized float number,
|
|
* store double float
|
|
*
|
|
* @fpu: Pointer to sh_fpu_hard structure
|
|
* @n: Index to FP register
|
|
*/
|
|
static void denormal_to_double(struct sh_fpu_hard_struct *fpu, int n)
|
|
{
|
|
unsigned long du, dl;
|
|
unsigned long x = fpu->fpul;
|
|
int exp = 1023 - 126;
|
|
|
|
if (x != 0 && (x & 0x7f800000) == 0) {
|
|
du = (x & 0x80000000);
|
|
while ((x & 0x00800000) == 0) {
|
|
x <<= 1;
|
|
exp--;
|
|
}
|
|
x &= 0x007fffff;
|
|
du |= (exp << 20) | (x >> 3);
|
|
dl = x << 29;
|
|
|
|
fpu->fp_regs[n] = du;
|
|
fpu->fp_regs[n + 1] = dl;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* ieee_fpe_handler - Handle denormalized number exception
|
|
*
|
|
* @regs: Pointer to register structure
|
|
*
|
|
* Returns 1 when it's handled (should not cause exception).
|
|
*/
|
|
static int ieee_fpe_handler(struct pt_regs *regs)
|
|
{
|
|
unsigned short insn = *(unsigned short *)regs->pc;
|
|
unsigned short finsn;
|
|
unsigned long nextpc;
|
|
int nib[4] = {
|
|
(insn >> 12) & 0xf,
|
|
(insn >> 8) & 0xf,
|
|
(insn >> 4) & 0xf,
|
|
insn & 0xf
|
|
};
|
|
|
|
if (nib[0] == 0xb || (nib[0] == 0x4 && nib[2] == 0x0 && nib[3] == 0xb))
|
|
regs->pr = regs->pc + 4; /* bsr & jsr */
|
|
|
|
if (nib[0] == 0xa || nib[0] == 0xb) {
|
|
/* bra & bsr */
|
|
nextpc = regs->pc + 4 + ((short)((insn & 0xfff) << 4) >> 3);
|
|
finsn = *(unsigned short *)(regs->pc + 2);
|
|
} else if (nib[0] == 0x8 && nib[1] == 0xd) {
|
|
/* bt/s */
|
|
if (regs->sr & 1)
|
|
nextpc = regs->pc + 4 + ((char)(insn & 0xff) << 1);
|
|
else
|
|
nextpc = regs->pc + 4;
|
|
finsn = *(unsigned short *)(regs->pc + 2);
|
|
} else if (nib[0] == 0x8 && nib[1] == 0xf) {
|
|
/* bf/s */
|
|
if (regs->sr & 1)
|
|
nextpc = regs->pc + 4;
|
|
else
|
|
nextpc = regs->pc + 4 + ((char)(insn & 0xff) << 1);
|
|
finsn = *(unsigned short *)(regs->pc + 2);
|
|
} else if (nib[0] == 0x4 && nib[3] == 0xb &&
|
|
(nib[2] == 0x0 || nib[2] == 0x2)) {
|
|
/* jmp & jsr */
|
|
nextpc = regs->regs[nib[1]];
|
|
finsn = *(unsigned short *)(regs->pc + 2);
|
|
} else if (nib[0] == 0x0 && nib[3] == 0x3 &&
|
|
(nib[2] == 0x0 || nib[2] == 0x2)) {
|
|
/* braf & bsrf */
|
|
nextpc = regs->pc + 4 + regs->regs[nib[1]];
|
|
finsn = *(unsigned short *)(regs->pc + 2);
|
|
} else if (insn == 0x000b) {
|
|
/* rts */
|
|
nextpc = regs->pr;
|
|
finsn = *(unsigned short *)(regs->pc + 2);
|
|
} else {
|
|
nextpc = regs->pc + instruction_size(insn);
|
|
finsn = insn;
|
|
}
|
|
|
|
if ((finsn & 0xf1ff) == 0xf0ad) {
|
|
/* fcnvsd */
|
|
struct task_struct *tsk = current;
|
|
|
|
if ((tsk->thread.xstate->hardfpu.fpscr & FPSCR_CAUSE_ERROR))
|
|
/* FPU error */
|
|
denormal_to_double(&tsk->thread.xstate->hardfpu,
|
|
(finsn >> 8) & 0xf);
|
|
else
|
|
return 0;
|
|
|
|
regs->pc = nextpc;
|
|
return 1;
|
|
} else if ((finsn & 0xf00f) == 0xf002) {
|
|
/* fmul */
|
|
struct task_struct *tsk = current;
|
|
int fpscr;
|
|
int n, m, prec;
|
|
unsigned int hx, hy;
|
|
|
|
n = (finsn >> 8) & 0xf;
|
|
m = (finsn >> 4) & 0xf;
|
|
hx = tsk->thread.xstate->hardfpu.fp_regs[n];
|
|
hy = tsk->thread.xstate->hardfpu.fp_regs[m];
|
|
fpscr = tsk->thread.xstate->hardfpu.fpscr;
|
|
prec = fpscr & FPSCR_DBL_PRECISION;
|
|
|
|
if ((fpscr & FPSCR_CAUSE_ERROR)
|
|
&& (prec && ((hx & 0x7fffffff) < 0x00100000
|
|
|| (hy & 0x7fffffff) < 0x00100000))) {
|
|
long long llx, lly;
|
|
|
|
/* FPU error because of denormal (doubles) */
|
|
llx = ((long long)hx << 32)
|
|
| tsk->thread.xstate->hardfpu.fp_regs[n + 1];
|
|
lly = ((long long)hy << 32)
|
|
| tsk->thread.xstate->hardfpu.fp_regs[m + 1];
|
|
llx = float64_mul(llx, lly);
|
|
tsk->thread.xstate->hardfpu.fp_regs[n] = llx >> 32;
|
|
tsk->thread.xstate->hardfpu.fp_regs[n + 1] = llx & 0xffffffff;
|
|
} else if ((fpscr & FPSCR_CAUSE_ERROR)
|
|
&& (!prec && ((hx & 0x7fffffff) < 0x00800000
|
|
|| (hy & 0x7fffffff) < 0x00800000))) {
|
|
/* FPU error because of denormal (floats) */
|
|
hx = float32_mul(hx, hy);
|
|
tsk->thread.xstate->hardfpu.fp_regs[n] = hx;
|
|
} else
|
|
return 0;
|
|
|
|
regs->pc = nextpc;
|
|
return 1;
|
|
} else if ((finsn & 0xf00e) == 0xf000) {
|
|
/* fadd, fsub */
|
|
struct task_struct *tsk = current;
|
|
int fpscr;
|
|
int n, m, prec;
|
|
unsigned int hx, hy;
|
|
|
|
n = (finsn >> 8) & 0xf;
|
|
m = (finsn >> 4) & 0xf;
|
|
hx = tsk->thread.xstate->hardfpu.fp_regs[n];
|
|
hy = tsk->thread.xstate->hardfpu.fp_regs[m];
|
|
fpscr = tsk->thread.xstate->hardfpu.fpscr;
|
|
prec = fpscr & FPSCR_DBL_PRECISION;
|
|
|
|
if ((fpscr & FPSCR_CAUSE_ERROR)
|
|
&& (prec && ((hx & 0x7fffffff) < 0x00100000
|
|
|| (hy & 0x7fffffff) < 0x00100000))) {
|
|
long long llx, lly;
|
|
|
|
/* FPU error because of denormal (doubles) */
|
|
llx = ((long long)hx << 32)
|
|
| tsk->thread.xstate->hardfpu.fp_regs[n + 1];
|
|
lly = ((long long)hy << 32)
|
|
| tsk->thread.xstate->hardfpu.fp_regs[m + 1];
|
|
if ((finsn & 0xf00f) == 0xf000)
|
|
llx = float64_add(llx, lly);
|
|
else
|
|
llx = float64_sub(llx, lly);
|
|
tsk->thread.xstate->hardfpu.fp_regs[n] = llx >> 32;
|
|
tsk->thread.xstate->hardfpu.fp_regs[n + 1] = llx & 0xffffffff;
|
|
} else if ((fpscr & FPSCR_CAUSE_ERROR)
|
|
&& (!prec && ((hx & 0x7fffffff) < 0x00800000
|
|
|| (hy & 0x7fffffff) < 0x00800000))) {
|
|
/* FPU error because of denormal (floats) */
|
|
if ((finsn & 0xf00f) == 0xf000)
|
|
hx = float32_add(hx, hy);
|
|
else
|
|
hx = float32_sub(hx, hy);
|
|
tsk->thread.xstate->hardfpu.fp_regs[n] = hx;
|
|
} else
|
|
return 0;
|
|
|
|
regs->pc = nextpc;
|
|
return 1;
|
|
} else if ((finsn & 0xf003) == 0xf003) {
|
|
/* fdiv */
|
|
struct task_struct *tsk = current;
|
|
int fpscr;
|
|
int n, m, prec;
|
|
unsigned int hx, hy;
|
|
|
|
n = (finsn >> 8) & 0xf;
|
|
m = (finsn >> 4) & 0xf;
|
|
hx = tsk->thread.xstate->hardfpu.fp_regs[n];
|
|
hy = tsk->thread.xstate->hardfpu.fp_regs[m];
|
|
fpscr = tsk->thread.xstate->hardfpu.fpscr;
|
|
prec = fpscr & FPSCR_DBL_PRECISION;
|
|
|
|
if ((fpscr & FPSCR_CAUSE_ERROR)
|
|
&& (prec && ((hx & 0x7fffffff) < 0x00100000
|
|
|| (hy & 0x7fffffff) < 0x00100000))) {
|
|
long long llx, lly;
|
|
|
|
/* FPU error because of denormal (doubles) */
|
|
llx = ((long long)hx << 32)
|
|
| tsk->thread.xstate->hardfpu.fp_regs[n + 1];
|
|
lly = ((long long)hy << 32)
|
|
| tsk->thread.xstate->hardfpu.fp_regs[m + 1];
|
|
|
|
llx = float64_div(llx, lly);
|
|
|
|
tsk->thread.xstate->hardfpu.fp_regs[n] = llx >> 32;
|
|
tsk->thread.xstate->hardfpu.fp_regs[n + 1] = llx & 0xffffffff;
|
|
} else if ((fpscr & FPSCR_CAUSE_ERROR)
|
|
&& (!prec && ((hx & 0x7fffffff) < 0x00800000
|
|
|| (hy & 0x7fffffff) < 0x00800000))) {
|
|
/* FPU error because of denormal (floats) */
|
|
hx = float32_div(hx, hy);
|
|
tsk->thread.xstate->hardfpu.fp_regs[n] = hx;
|
|
} else
|
|
return 0;
|
|
|
|
regs->pc = nextpc;
|
|
return 1;
|
|
} else if ((finsn & 0xf0bd) == 0xf0bd) {
|
|
/* fcnvds - double to single precision convert */
|
|
struct task_struct *tsk = current;
|
|
int m;
|
|
unsigned int hx;
|
|
|
|
m = (finsn >> 8) & 0x7;
|
|
hx = tsk->thread.xstate->hardfpu.fp_regs[m];
|
|
|
|
if ((tsk->thread.xstate->hardfpu.fpscr & FPSCR_CAUSE_ERROR)
|
|
&& ((hx & 0x7fffffff) < 0x00100000)) {
|
|
/* subnormal double to float conversion */
|
|
long long llx;
|
|
|
|
llx = ((long long)tsk->thread.xstate->hardfpu.fp_regs[m] << 32)
|
|
| tsk->thread.xstate->hardfpu.fp_regs[m + 1];
|
|
|
|
tsk->thread.xstate->hardfpu.fpul = float64_to_float32(llx);
|
|
} else
|
|
return 0;
|
|
|
|
regs->pc = nextpc;
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void float_raise(unsigned int flags)
|
|
{
|
|
fpu_exception_flags |= flags;
|
|
}
|
|
|
|
int float_rounding_mode(void)
|
|
{
|
|
struct task_struct *tsk = current;
|
|
int roundingMode = FPSCR_ROUNDING_MODE(tsk->thread.xstate->hardfpu.fpscr);
|
|
return roundingMode;
|
|
}
|
|
|
|
BUILD_TRAP_HANDLER(fpu_error)
|
|
{
|
|
struct task_struct *tsk = current;
|
|
TRAP_HANDLER_DECL;
|
|
|
|
__unlazy_fpu(tsk, regs);
|
|
fpu_exception_flags = 0;
|
|
if (ieee_fpe_handler(regs)) {
|
|
tsk->thread.xstate->hardfpu.fpscr &=
|
|
~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK);
|
|
tsk->thread.xstate->hardfpu.fpscr |= fpu_exception_flags;
|
|
/* Set the FPSCR flag as well as cause bits - simply
|
|
* replicate the cause */
|
|
tsk->thread.xstate->hardfpu.fpscr |= (fpu_exception_flags >> 10);
|
|
grab_fpu(regs);
|
|
restore_fpu(tsk);
|
|
task_thread_info(tsk)->status |= TS_USEDFPU;
|
|
if ((((tsk->thread.xstate->hardfpu.fpscr & FPSCR_ENABLE_MASK) >> 7) &
|
|
(fpu_exception_flags >> 2)) == 0) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
force_sig(SIGFPE, tsk);
|
|
}
|