NetBSD/sys/arch/sparc/sparc/emul.c

445 lines
10 KiB
C

/* $NetBSD: emul.c,v 1.3 1997/07/29 09:42:01 fair Exp $ */
/*
* Copyright (c) 1997 Christos Zoulas. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Christos Zoulas.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <machine/reg.h>
#include <machine/instr.h>
#include <machine/cpu.h>
#include <machine/psl.h>
#include <sparc/sparc/cpuvar.h>
#ifdef DEBUG_EMUL
# define DPRINTF(a) uprintf a
#else
# define DPRINTF(a)
#endif
#define GPR(tf, i) ((int32_t *) &tf->tf_global)[i]
#define IPR(tf, i) ((int32_t *) tf->tf_out[6])[i - 16]
#define FPR(p, i) ((int32_t) p->p_md.md_fpstate->fs_regs[i])
static __inline int readgpreg __P((struct trapframe *, int, void *));
static __inline int readfpreg __P((struct proc *, int, void *));
static __inline int writegpreg __P((struct trapframe *, int, const void *));
static __inline int writefpreg __P((struct proc *, int, const void *));
static __inline int decodeaddr __P((struct trapframe *, union instr *, void *));
static int muldiv __P((struct trapframe *, union instr *, int32_t *, int32_t *,
int32_t *));
#define REGNAME(i) "goli"[i >> 3], i & 7
static __inline int
readgpreg(tf, i, val)
struct trapframe *tf;
int i;
void *val;
{
int error = 0;
if (i == 0)
*(int32_t *) val = 0;
else if (i < 16)
*(int32_t *) val = GPR(tf, i);
else
error = copyin(&IPR(tf, i), val, sizeof(int32_t));
return error;
}
static __inline int
writegpreg(tf, i, val)
struct trapframe *tf;
int i;
const void *val;
{
int error = 0;
if (i == 0)
return error;
else if (i < 16)
GPR(tf, i) = *(int32_t *) val;
else
/* XXX: Fix copyout prototype */
error = copyout((caddr_t) val, &IPR(tf, i), sizeof(int32_t));
return error;
}
static __inline int
readfpreg(p, i, val)
struct proc *p;
int i;
void *val;
{
*(int32_t *) val = FPR(p, i);
return 0;
}
static __inline int
writefpreg(p, i, val)
struct proc *p;
int i;
const void *val;
{
FPR(p, i) = *(const int32_t *) val;
return 0;
}
static __inline int
decodeaddr(tf, code, val)
struct trapframe *tf;
union instr *code;
void *val;
{
if (code->i_simm13.i_i)
*((int32_t *) val) = code->i_simm13.i_simm13;
else {
int error;
if (code->i_asi.i_asi)
return EINVAL;
if ((error = readgpreg(tf, code->i_asi.i_rs2, val)) != 0)
return error;
}
return 0;
}
static int
muldiv(tf, code, rd, rs1, rs2)
struct trapframe *tf;
union instr *code;
int32_t *rd, *rs1, *rs2;
{
/*
* We check for {S,U}{MUL,DIV}{,cc}
*
* [c = condition code, s = sign]
* Mul = 0c101s
* Div = 0c111s
*/
union {
struct {
unsigned unused:26; /* padding */
unsigned zero:1; /* zero by opcode */
unsigned cc:1; /* one to send condition code */
unsigned one1:1; /* one by opcode */
unsigned div:1; /* one if divide */
unsigned one2:1; /* one by opcode */
unsigned sgn:1; /* sign bit */
} bits;
int num;
} op;
op.num = code->i_op3.i_op3;
#ifdef DEBUG_EMUL
uprintf("muldiv 0x%x: %c%s%s %c%d, %c%d, ", code->i_int,
"us"[op.bits.sgn], op.bits.div ? "div" : "mul",
op.bits.cc ? "cc" : "", REGNAME(code->i_op3.i_rd),
REGNAME(code->i_op3.i_rs1));
if (code->i_loadstore.i_i)
uprintf("0x%x\n", *rs2);
else
uprintf("%c%d\n", REGNAME(code->i_asi.i_rs2));
#endif
if (op.bits.div) {
if (*rs2 == 0) {
/*
* XXX: to be 100% correct here, on sunos we need to
* ignore the error and return *rd = *rs1.
* It should be easy to fix by passing struct
* proc in here.
*/
DPRINTF(("emulinstr: avoid zerodivide\n"));
return EINVAL;
}
*rd = *rs1 / *rs2;
DPRINTF(("muldiv: %d / %d = %d\n", *rs1, *rs2, *rd));
}
else {
*rd = *rs1 * *rs2;
DPRINTF(("muldiv: %d * %d = %d\n", *rs1, *rs2, *rd));
}
if (op.bits.cc) {
/* Set condition codes */
tf->tf_psr &= ~PSR_ICC;
if (*rd == 0)
tf->tf_psr |= PSR_Z << 20;
else {
if (op.bits.sgn && *rd < 0)
tf->tf_psr |= PSR_N << 20;
if (op.bits.div) {
if (*rd * *rs2 != *rs1)
tf->tf_psr |= PSR_O << 20;
}
else {
if (*rd / *rs2 != *rs1)
tf->tf_psr |= PSR_O << 20;
}
}
}
return 0;
}
/*
* Code to handle alignment faults on the sparc. This is enabled by sending
* a fixalign trap. Such code is generated by compiling with cc -misalign
* on SunOS, but we don't have such a feature yet on our gcc.
*/
int
fixalign(p, tf)
struct proc *p;
struct trapframe *tf;
{
static u_char sizedef[] = { 0x4, 0xff, 0x2, 0x8 };
/*
* This is particular to load and store instructions
*/
union {
struct {
unsigned unused:26; /* 26 padding */
unsigned fl:1; /* 1 bit float flag */
unsigned op:1; /* 1 bit opcode */
unsigned sgn:1; /* 1 bit sign */
unsigned st:1; /* 1 bit load/store */
unsigned sz:2; /* 2 bit size register */
} bits;
int num;
} op;
union {
double d;
int32_t i[2];
int16_t s[4];
int8_t c[8];
} data;
union instr code;
size_t size;
int32_t rs1, rs2;
int error;
/* fetch and check the instruction that caused the fault */
error = copyin((caddr_t) tf->tf_pc, &code.i_int, sizeof(code.i_int));
if (error != 0) {
DPRINTF(("fixalign: Bad instruction fetch\n"));
return EINVAL;
}
/* Only support format 3 */
if (code.i_any.i_op != 3) {
DPRINTF(("fixalign: Not a load or store\n"));
return EINVAL;
}
op.num = code.i_loadstore.i_op3;
/* Check operand size */
if ((size = sizedef[op.bits.sz]) == 0xff) {
DPRINTF(("fixalign: Bad operand size\n"));
return EINVAL;
}
write_user_windows();
if ((error = readgpreg(tf, code.i_op3.i_rs1, &rs1)) != 0) {
DPRINTF(("emulinstr: read rs1 %d\n", error));
return error;
}
if ((error = decodeaddr(tf, &code, &rs2)) != 0) {
DPRINTF(("emulinstr: decode addr %d\n", error));
return error;
}
rs1 += rs2;
#ifdef DEBUG_EMUL
uprintf("memalign 0x%x: %s%c%c %c%d, %c%d, ", code.i_int,
op.bits.st ? "st" : "ld", "us"[op.bits.sgn],
"w*hd"[op.bits.sz], op.bits.fl ? 'f' : REGNAME(code.i_op3.i_rd),
REGNAME(code.i_op3.i_rs1));
if (code.i_loadstore.i_i)
uprintf("0x%x\n", rs2);
else
uprintf("%c%d\n", REGNAME(code.i_asi.i_rs2));
#endif
#ifdef DIAGNOSTIC
if (op.bits.fl && p != fpproc)
panic("fp align without being the FP owning process");
#endif
if (op.bits.st) {
if (op.bits.fl) {
savefpstate(p->p_md.md_fpstate);
error = readfpreg(p, code.i_op3.i_rd, &data.i[0]);
if (error)
return error;
if (size == 8) {
error = readfpreg(p, code.i_op3.i_rd + 1,
&data.i[1]);
if (error)
return error;
}
}
else {
error = readgpreg(tf, code.i_op3.i_rd, &data.i[0]);
if (error)
return error;
if (size == 8) {
error = readgpreg(tf, code.i_op3.i_rd + 1,
&data.i[1]);
if (error)
return error;
}
}
if (size == 2)
return copyout(&data.s[1], (caddr_t) rs1, size);
else
return copyout(&data.d, (caddr_t) rs1, size);
}
else { /* load */
if (size == 2) {
error = copyin((caddr_t) rs1, &data.s[1], size);
if (error)
return error;
/* Sign extend if necessary */
if (op.bits.sgn && (data.s[1] & 0x8000) != 0)
data.s[0] = ~0;
else
data.s[0] = 0;
}
else
error = copyin((caddr_t) rs1, &data.d, size);
if (error)
return error;
if (op.bits.fl) {
error = writefpreg(p, code.i_op3.i_rd, &data.i[0]);
if (error)
return error;
if (size == 8) {
error = writefpreg(p, code.i_op3.i_rd + 1,
&data.i[1]);
if (error)
return error;
}
loadfpstate(p->p_md.md_fpstate);
}
else {
error = writegpreg(tf, code.i_op3.i_rd, &data.i[0]);
if (error)
return error;
if (size == 8)
error = writegpreg(tf, code.i_op3.i_rd + 1,
&data.i[1]);
}
}
return error;
}
/*
* Emulate unimplemented instructions on earlier sparc chips.
*/
int
emulinstr(pc, tf)
int pc;
struct trapframe *tf;
{
union instr code;
int32_t rs1, rs2, rd;
int error;
/* fetch and check the instruction that caused the fault */
error = copyin((caddr_t) pc, &code.i_int, sizeof(code.i_int));
if (error != 0) {
DPRINTF(("emulinstr: Bad instruction fetch\n"));
return SIGILL;
}
/* Only support format 2 */
if (code.i_any.i_op != 2) {
DPRINTF(("emulinstr: Not a format 2 instruction\n"));
return SIGILL;
}
write_user_windows();
if ((error = readgpreg(tf, code.i_op3.i_rs1, &rs1)) != 0) {
DPRINTF(("emulinstr: read rs1 %d\n", error));
return SIGILL;
}
if ((error = decodeaddr(tf, &code, &rs2)) != 0) {
DPRINTF(("emulinstr: decode addr %d\n", error));
return SIGILL;
}
switch (code.i_op3.i_op3) {
case IOP3_FLUSH:
cpuinfo.cache_flush((caddr_t)(rs1 + rs2), 4); /*XXX*/
return 0;
default:
if ((code.i_op3.i_op3 & 0x2a) != 0xa) {
DPRINTF(("emulinstr: Unsupported op3 0x%x\n",
code.i_op3.i_op3));
return SIGILL;
}
else if ((error = muldiv(tf, &code, &rd, &rs1, &rs2)) != 0)
return SIGFPE;
}
if ((error = writegpreg(tf, code.i_op3.i_rd, &rd)) != 0) {
DPRINTF(("muldiv: write rd %d\n", error));
return SIGILL;
}
return 0;
}