+// vim:shiftwidth=2:expandtab
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <signal.h>
+#include <asm/ucontext.h>
+
+#include "header.h"
+
+#define iolog printf
+//#define iolog(...)
+
+typedef unsigned int u32;
+typedef unsigned short u16;
+typedef unsigned char u8;
+
+static int memdev;
+static volatile u16 *memregs, *blitter;
+
+
+static volatile void *translate_addr(u32 a, u32 *mask)
+{
+ if ((a & 0xfff00000) == 0x7f000000) {
+ *mask = 0xffff;
+ return memregs;
+ }
+ if ((a & 0xfff00000) == 0x7f100000) {
+ *mask = 0xff;
+ return blitter;
+ }
+ fprintf(stderr, "bad IO @ %08x\n", a);
+ abort();
+}
+
+static u32 xread8(u32 a)
+{
+ volatile u8 *mem;
+ u32 mask;
+
+ iolog("r8 %08x\n", a);
+ mem = translate_addr(a, &mask);
+ return mem[a & mask];
+}
+
+static u32 xread16(u32 a)
+{
+ volatile u16 *mem;
+ u32 mask;
+
+ iolog("r16 %08x\n", a);
+ mem = translate_addr(a, &mask);
+ return mem[(a & mask) / 2];
+}
+
+static u32 xread32(u32 a)
+{
+ volatile u32 *mem;
+ u32 mask;
+
+ iolog("r32 %08x\n", a);
+ mem = translate_addr(a, &mask);
+ return mem[(a & mask) / 4];
+}
+
+static void xwrite8(u32 a, u32 d)
+{
+ volatile u8 *mem;
+ u32 mask;
+
+ iolog("w8 %08x %08x\n", a, d);
+ mem = translate_addr(a, &mask);
+ mem[a & mask] = d;
+}
+
+static void xwrite16(u32 a, u32 d)
+{
+ volatile u16 *mem;
+ u32 mask;
+
+ iolog("w16 %08x %08x\n", a, d);
+ mem = translate_addr(a, &mask);
+ mem[(a & mask) / 2] = d;
+}
+
+static void xwrite32(u32 a, u32 d)
+{
+ volatile u32 *mem;
+ u32 mask;
+
+ iolog("w32 %08x %08x\n", a, d);
+ mem = translate_addr(a, &mask);
+ mem[(a & mask) / 4] = d;
+}
+
+#define BIT_SET(v, b) (v & (1 << (b)))
+
+static void handle_op(u32 addr_pc, u32 op, u32 *regs, u32 addr_check)
+{
+ u32 t, shift, ret, addr;
+ int rn, rd;
+
+ rd = (op & 0x0000f000) >> 12;
+ rn = (op & 0x000f0000) >> 16;
+
+ if ((op & 0x0f200090) == 0x01000090) { // AM3: LDRH, STRH
+ if (BIT_SET(op, 6)) // S
+ goto unhandled;
+
+ if (BIT_SET(op, 22)) // imm offset
+ t = ((op & 0xf00) >> 4) | (op & 0x0f);
+ else // reg offset
+ t = regs[op & 0x000f];
+
+ if (!BIT_SET(op, 23))
+ t = -t;
+ addr = regs[rn] + t;
+
+ if (BIT_SET(op, 20)) { // Load
+ ret = xread16(addr);
+ regs[rd] = ret;
+ }
+ else
+ xwrite16(addr, regs[rd]);
+ }
+ else if ((op & 0x0d200000) == 0x05000000) { // AM2: LDR[B], STR[B]
+ if (BIT_SET(op, 25)) { // reg offs
+ if (BIT_SET(op, 4))
+ goto unhandled;
+
+ t = regs[op & 0x000f];
+ shift = (op & 0x0f80) >> 7;
+ switch ((op & 0x0060) >> 5) {
+ case 0: t = t << shift; break;
+ case 1: t = t >> (shift + 1); break;
+ case 2: t = (signed int)t >> (shift + 1); break;
+ case 3: goto unhandled; // I'm just lazy
+ }
+ }
+ else // imm offs
+ t = op & 0x0fff;
+
+ if (!BIT_SET(op, 23))
+ t = -t;
+ addr = regs[rn] + t;
+
+ if (BIT_SET(op, 20)) { // Load
+ if (BIT_SET(op, 22)) // Byte
+ ret = xread8(addr);
+ else
+ ret = xread32(addr);
+ regs[rd] = ret;
+ }
+ else {
+ if (BIT_SET(op, 22)) // Byte
+ xwrite8(addr, regs[rd]);
+ else
+ xwrite32(addr, regs[rd]);
+ }
+ }
+ else
+ goto unhandled;
+
+ if (addr != addr_check) {
+ fprintf(stderr, "bad calculated addr: %08x vs %08x\n", addr, addr_check);
+ abort();
+ }
+ return;
+
+unhandled:
+ fprintf(stderr, "unhandled IO op %08x @ %08x\n", op, addr_pc);
+}
+
+static void segv_sigaction(int num, siginfo_t *info, void *ctx)
+{
+ struct ucontext *context = ctx;
+ u32 *regs = (u32 *)&context->uc_mcontext.arm_r0;
+ u32 op = *(u32 *)regs[15];
+
+ //printf("segv %d %p @ %08x\n", info->si_code, info->si_addr, regs[15]);
+/*
+ static int thissec, sfps;
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ sfps++;
+ if (tv.tv_sec != thissec) {
+ printf("%d\n", sfps);
+ sfps = 0;
+ thissec = tv.tv_sec;
+ }
+*/
+
+ handle_op(regs[15], op, regs, (u32)info->si_addr);
+ regs[15] += 4;
+ return;
+
+ //signal(num, SIG_DFL);
+ //raise(num);
+}
+
+#define LINKPAGE_SIZE 0x1000
+
+struct linkpage {
+ u32 (*xread8)(u32 a);
+ u32 (*xread16)(u32 a);
+ u32 (*xread32)(u32 a);
+ void (*xwrite8)(u32 a, u32 d);
+ void (*xwrite16)(u32 a, u32 d);
+ void (*xwrite32)(u32 a, u32 d);
+ u32 retval;
+ u32 *reg_ptr;
+ u32 saved_regs[6]; // r0-r3,r12,lr
+ u32 code[0];
+};
+
+static struct linkpage *g_linkpage;
+static u32 *g_code_ptr;
+
+void emu_init(void *map_bottom)
+{
+ struct sigaction segv_action = {
+ .sa_sigaction = segv_sigaction,
+ .sa_flags = SA_SIGINFO,
+ };
+ struct linkpage init_linkpage = {
+ .xread8 = xread8,
+ .xread16 = xread16,
+ .xread32 = xread32,
+ .xwrite8 = xwrite8,
+ .xwrite16 = xwrite16,
+ .xwrite32 = xwrite32,
+ };
+ void *ret;
+
+ sigemptyset(&segv_action.sa_mask);
+ sigaction(SIGSEGV, &segv_action, NULL);
+
+ g_linkpage = (void *)(((u32)map_bottom - LINKPAGE_SIZE) & ~0xfff);
+ ret = mmap(g_linkpage, LINKPAGE_SIZE, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+ if (ret != g_linkpage) {
+ perror("mmap linkpage");
+ exit(1);
+ }
+ printf("linkpage @ %p\n", g_linkpage);
+ memcpy(g_linkpage, &init_linkpage, sizeof(*g_linkpage));
+ g_linkpage->reg_ptr = g_linkpage->saved_regs;
+ g_code_ptr = g_linkpage->code;
+
+ memdev = open("/dev/mem", O_RDWR);
+ memregs = mmap(NULL, 0x10000, PROT_READ|PROT_WRITE, MAP_SHARED, memdev, 0xc0000000);
+ blitter = mmap(NULL, 0x100, PROT_READ|PROT_WRITE, MAP_SHARED, memdev, 0xe0020000);
+ printf("mapped %d %p %p\n", memdev, memregs, blitter);
+}
+
+void *emu_mmap_dev(unsigned int length, int prot, int flags, unsigned int offset)
+{
+ char name[32];
+ int fd;
+
+ if ((offset & ~0xffff) == 0xc0000000) {
+ return mmap((void *)0x7f000000, length, PROT_NONE,
+ MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED|MAP_NORESERVE, -1, 0);
+ }
+ if ((offset & ~0xffff) == 0xe0020000) {
+ return mmap((void *)0x7f100000, length, PROT_NONE,
+ MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED|MAP_NORESERVE, -1, 0);
+ }
+ // pass through
+ if ((offset & 0xfe000000) == 0x02000000)
+ return mmap(NULL, length, prot, flags, memdev, offset);
+
+ sprintf(name, "m%08x", offset);
+ fd = open(name, O_CREAT|O_RDWR, 0644);
+ lseek(fd, length - 1, SEEK_SET);
+ name[0] = 0;
+ write(fd, name, 1);
+
+ return mmap(NULL, length, prot, MAP_SHARED, fd, 0);
+}
+
notaz.gp2x.de / ginge.git / commitdiff