diff options
Diffstat (limited to 'nor.c')
| -rw-r--r-- | nor.c | 33 |
1 files changed, 23 insertions, 10 deletions
@@ -1,6 +1,7 @@ #include "genesis.h" #include <stdlib.h> #include <string.h> +#include "util.h" enum { NOR_NORMAL, @@ -31,9 +32,11 @@ void nor_flash_init(nor_state *state, uint8_t *buffer, uint32_t size, uint32_t p state->cmd_state = NOR_CMD_IDLE; state->alt_cmd = 0; state->bus_flags = bus_flags; + state->cmd_address1 = 0x5555; + state->cmd_address2 = 0x2AAA; } -void nor_run(nor_state *state, uint32_t cycle) +void nor_run(nor_state *state, m68k_context *m68k, uint32_t cycle) { if (state->last_write_cycle == 0xFFFFFFFF) { return; @@ -44,6 +47,10 @@ void nor_run(nor_state *state, uint32_t cycle) state->buffer[state->current_page + i] = state->page_buffer[i]; } memset(state->page_buffer, 0xFF, state->page_size); + if (state->bus_flags == RAM_FLAG_BOTH) { + //TODO: add base address of NOR device to start and end addresses + m68k_invalidate_code_range(m68k, state->current_page, state->current_page + state->page_size); + } } } @@ -62,10 +69,13 @@ uint8_t nor_flash_read_b(uint32_t address, void *vcontext) address = address >> 1; } - nor_run(state, m68k->current_cycle); + nor_run(state, m68k, m68k->current_cycle); switch (state->mode) { case NOR_NORMAL: + if (state->bus_flags == RAM_FLAG_BOTH) { + address ^= 1; + } return state->buffer[address & (state->size-1)]; break; case NOR_PRODUCTID: @@ -80,7 +90,7 @@ uint8_t nor_flash_read_b(uint32_t address, void *vcontext) return 0xFE; default: return 0xFE; - } + } //HERE break; case NOR_BOOTBLOCK: break; @@ -103,6 +113,9 @@ void nor_write_byte(nor_state *state, uint32_t address, uint8_t value, uint32_t if (state->last_write_cycle != 0xFFFFFFFF) { state->current_page = address & (state->size - 1) & ~(state->page_size - 1); } + if (state->bus_flags == RAM_FLAG_BOTH) { + address ^= 1; + } state->page_buffer[address & (state->page_size - 1)] = value; break; case NOR_PRODUCTID: @@ -129,11 +142,11 @@ void *nor_flash_write_b(uint32_t address, void *vcontext, uint8_t value) address = address >> 1; } - nor_run(state, m68k->current_cycle); + nor_run(state, m68k, m68k->current_cycle); switch (state->cmd_state) { case NOR_CMD_IDLE: - if (value == 0xAA && (address & (state->size - 1)) == 0x5555) { + if (value == 0xAA && (address & (state->size - 1)) == state->cmd_address1) { state->cmd_state = NOR_CMD_AA; } else { nor_write_byte(state, address, value, m68k->current_cycle); @@ -141,16 +154,16 @@ void *nor_flash_write_b(uint32_t address, void *vcontext, uint8_t value) } break; case NOR_CMD_AA: - if (value == 0x55 && (address & (state->size - 1)) == 0x2AAA) { + if (value == 0x55 && (address & (state->size - 1)) == state->cmd_address2) { state->cmd_state = NOR_CMD_55; } else { - nor_write_byte(state, 0x5555, 0xAA, m68k->current_cycle); + nor_write_byte(state, state->cmd_address1, 0xAA, m68k->current_cycle); nor_write_byte(state, address, value, m68k->current_cycle); state->cmd_state = NOR_CMD_IDLE; } break; case NOR_CMD_55: - if ((address & (state->size - 1)) == 0x5555) { + if ((address & (state->size - 1)) == state->cmd_address1) { if (state->alt_cmd) { switch(value) { @@ -187,8 +200,8 @@ void *nor_flash_write_b(uint32_t address, void *vcontext, uint8_t value) } } } else { - nor_write_byte(state, 0x5555, 0xAA, m68k->current_cycle); - nor_write_byte(state, 0x2AAA, 0x55, m68k->current_cycle); + nor_write_byte(state, state->cmd_address1, 0xAA, m68k->current_cycle); + nor_write_byte(state, state->cmd_address2, 0x55, m68k->current_cycle); nor_write_byte(state, address, value, m68k->current_cycle); } state->cmd_state = NOR_CMD_IDLE; |