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Diffstat (limited to 'sim/erc32/erc32.c')
-rw-r--r--sim/erc32/erc32.c175
1 files changed, 34 insertions, 141 deletions
diff --git a/sim/erc32/erc32.c b/sim/erc32/erc32.c
index 7f24fb0..4d4ad04 100644
--- a/sim/erc32/erc32.c
+++ b/sim/erc32/erc32.c
@@ -54,11 +54,6 @@ int dumbio = 0; /* normal, smart, terminal oriented IO by default */
extern int errmec;
#endif
-/* The target's byte order is big-endian by default until we load a
- little-endian program. */
-
-int current_target_byte_order = BIG_ENDIAN;
-
#define MEC_WS 0 /* Waitstates per MEC access (0 ws) */
#define MOK 0
@@ -296,11 +291,8 @@ static void gpt_reload_set (uint32 val);
static void timer_ctrl (uint32 val);
static unsigned char *
get_mem_ptr (uint32 addr, uint32 size);
-
-static void fetch_bytes (int asi, unsigned char *mem,
- uint32 *data, int sz);
-
-static void store_bytes (unsigned char *mem, uint32 *data, int sz);
+static void store_bytes (unsigned char *mem, uint32 waddr,
+ uint32 *data, int sz, int32 *ws);
extern int ext_irl;
@@ -1524,123 +1516,38 @@ timer_ctrl(val)
gpt_start();
}
-
-/* Retrieve data from target memory. MEM points to location from which
- to read the data; DATA points to words where retrieved data will be
- stored in host byte order. SZ contains log(2) of the number of bytes
- to retrieve, and can be 0 (1 byte), 1 (one half-word), 2 (one word),
- or 3 (two words). */
+/* Store data in host byte order. MEM points to the beginning of the
+ emulated memory; WADDR contains the index the emulated memory,
+ DATA points to words in host byte order to be stored. SZ contains log(2)
+ of the number of bytes to retrieve, and can be 0 (1 byte), 1 (one half-word),
+ 2 (one word), or 3 (two words); WS should return the number of
+ wait-states. */
static void
-fetch_bytes (asi, mem, data, sz)
- int asi;
- unsigned char *mem;
- uint32 *data;
- int sz;
+store_bytes (unsigned char *mem, uint32 waddr, uint32 *data, int32 sz,
+ int32 *ws)
{
- if (CURRENT_TARGET_BYTE_ORDER == BIG_ENDIAN
- || asi == 8 || asi == 9) {
- switch (sz) {
- case 3:
- data[1] = (((uint32) mem[7]) & 0xff) |
- ((((uint32) mem[6]) & 0xff) << 8) |
- ((((uint32) mem[5]) & 0xff) << 16) |
- ((((uint32) mem[4]) & 0xff) << 24);
- /* Fall through to 2 */
- case 2:
- data[0] = (((uint32) mem[3]) & 0xff) |
- ((((uint32) mem[2]) & 0xff) << 8) |
- ((((uint32) mem[1]) & 0xff) << 16) |
- ((((uint32) mem[0]) & 0xff) << 24);
- break;
- case 1:
- data[0] = (((uint32) mem[1]) & 0xff) |
- ((((uint32) mem[0]) & 0xff) << 8);
- break;
+ switch (sz) {
case 0:
- data[0] = mem[0] & 0xff;
- break;
-
- }
- } else {
- switch (sz) {
- case 3:
- data[1] = ((((uint32) mem[7]) & 0xff) << 24) |
- ((((uint32) mem[6]) & 0xff) << 16) |
- ((((uint32) mem[5]) & 0xff) << 8) |
- (((uint32) mem[4]) & 0xff);
- /* Fall through to 4 */
- case 2:
- data[0] = ((((uint32) mem[3]) & 0xff) << 24) |
- ((((uint32) mem[2]) & 0xff) << 16) |
- ((((uint32) mem[1]) & 0xff) << 8) |
- (((uint32) mem[0]) & 0xff);
+ waddr ^= EBT;
+ mem[waddr] = *data & 0x0ff;
+ *ws = mem_ramw_ws + 3;
break;
case 1:
- data[0] = ((((uint32) mem[1]) & 0xff) << 8) |
- (((uint32) mem[0]) & 0xff);
- break;
- case 0:
- data[0] = mem[0] & 0xff;
+#ifdef HOST_LITTLE_ENDIAN
+ waddr ^= 2;
+#endif
+ memcpy (&mem[waddr], data, 2);
+ *ws = mem_ramw_ws + 3;
break;
- }
- }
-}
-
-
-/* Store data in target byte order. MEM points to location to store data;
- DATA points to words in host byte order to be stored. SZ contains log(2)
- of the number of bytes to retrieve, and can be 0 (1 byte), 1 (one half-word),
- 2 (one word), or 3 (two words). */
-
-static void
-store_bytes (mem, data, sz)
- unsigned char *mem;
- uint32 *data;
- int sz;
-{
- if (CURRENT_TARGET_BYTE_ORDER == LITTLE_ENDIAN) {
- switch (sz) {
- case 3:
- mem[7] = (data[1] >> 24) & 0xff;
- mem[6] = (data[1] >> 16) & 0xff;
- mem[5] = (data[1] >> 8) & 0xff;
- mem[4] = data[1] & 0xff;
- /* Fall through to 2 */
case 2:
- mem[3] = (data[0] >> 24) & 0xff;
- mem[2] = (data[0] >> 16) & 0xff;
- /* Fall through to 1 */
- case 1:
- mem[1] = (data[0] >> 8) & 0xff;
- /* Fall through to 0 */
- case 0:
- mem[0] = data[0] & 0xff;
+ memcpy (&mem[waddr], data, 4);
+ *ws = mem_ramw_ws;
break;
- }
- } else {
- switch (sz) {
case 3:
- mem[7] = data[1] & 0xff;
- mem[6] = (data[1] >> 8) & 0xff;
- mem[5] = (data[1] >> 16) & 0xff;
- mem[4] = (data[1] >> 24) & 0xff;
- /* Fall through to 2 */
- case 2:
- mem[3] = data[0] & 0xff;
- mem[2] = (data[0] >> 8) & 0xff;
- mem[1] = (data[0] >> 16) & 0xff;
- mem[0] = (data[0] >> 24) & 0xff;
- break;
- case 1:
- mem[1] = data[0] & 0xff;
- mem[0] = (data[0] >> 8) & 0xff;
- break;
- case 0:
- mem[0] = data[0] & 0xff;
+ memcpy (&mem[waddr], data, 8);
+ *ws = 2 * mem_ramw_ws + STD_WS;
break;
-
- }
}
}
@@ -1695,7 +1602,7 @@ memory_read(asi, addr, data, sz, ws)
#endif
if ((addr >= mem_ramstart) && (addr < (mem_ramstart + mem_ramsz))) {
- fetch_bytes (asi, &ramb[addr & mem_rammask], data, sz);
+ memcpy (data, &ramb[addr & mem_rammask & ~3], 4);
*ws = mem_ramr_ws;
return 0;
} else if ((addr >= MEC_START) && (addr < MEC_END)) {
@@ -1713,7 +1620,7 @@ memory_read(asi, addr, data, sz, ws)
} else if (era) {
if ((addr < 0x100000) ||
((addr>= 0x80000000) && (addr < 0x80100000))) {
- fetch_bytes (asi, &romb[addr & ROM_MASK], data, sz);
+ memcpy (data, &romb[addr & ROM_MASK & ~3], 4);
*ws = 4;
return 0;
} else if ((addr >= 0x10000000) &&
@@ -1724,13 +1631,12 @@ memory_read(asi, addr, data, sz, ws)
}
} else if (addr < mem_romsz) {
- fetch_bytes (asi, &romb[addr], data, sz);
- *ws = mem_romr_ws;
- return 0;
-
+ memcpy (data, &romb[addr & ~3], 4);
+ *ws = mem_romr_ws;
+ return 0;
#else
} else if (addr < mem_romsz) {
- fetch_bytes (asi, &romb[addr], data, sz);
+ memcpy (data, &romb[addr & ~3], 4);
*ws = mem_romr_ws;
return 0;
#endif
@@ -1793,21 +1699,8 @@ memory_write(asi, addr, data, sz, ws)
return 1;
}
}
-
- store_bytes (&ramb[addr & mem_rammask], data, sz);
-
- switch (sz) {
- case 0:
- case 1:
- *ws = mem_ramw_ws + 3;
- break;
- case 2:
- *ws = mem_ramw_ws;
- break;
- case 3:
- *ws = 2 * mem_ramw_ws + STD_WS;
- break;
- }
+ waddr = addr & mem_rammask;
+ store_bytes (ramb, waddr, data, sz, ws);
return 0;
} else if ((addr >= MEC_START) && (addr < MEC_END)) {
if ((sz != 2) || (asi != 0xb)) {
@@ -1831,7 +1724,7 @@ memory_write(asi, addr, data, sz, ws)
((addr < 0x100000) || ((addr >= 0x80000000) && (addr < 0x80100000)))) {
addr &= ROM_MASK;
*ws = sz == 3 ? 8 : 4;
- store_bytes (&romb[addr], data, sz);
+ store_bytes (romb, addr, data, sz, ws);
return 0;
} else if ((addr >= 0x10000000) &&
(addr < (0x10000000 + (512 << (mec_iocr & 0x0f)))) &&
@@ -1847,7 +1740,7 @@ memory_write(asi, addr, data, sz, ws)
*ws = mem_romw_ws + 1;
if (sz == 3)
*ws += mem_romw_ws + STD_WS;
- store_bytes (&romb[addr], data, sz);
+ store_bytes (romb, addr, data, sz, ws);
return 0;
#else
@@ -1858,7 +1751,7 @@ memory_write(asi, addr, data, sz, ws)
*ws = mem_romw_ws + 1;
if (sz == 3)
*ws += mem_romw_ws + STD_WS;
- store_bytes (&romb[addr], data, sz);
+ store_bytes (romb, addr, data, sz, ws);
return 0;
#endif
generated by cgit v1.1 at 2024-11-24 09:15:56 +0000