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changeset 1080:382614130914

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Some initial work on Atari Jaguar emulation
author Michael Pavone <pavone@retrodev.com>
date Tue, 04 Oct 2016 18:30:49 -0700
parents 329ff62ea391
children 89cc20cf1ad3
files Makefile jaguar.c jaguar.h
diffstat 3 files changed, 326 insertions(+), 0 deletions(-) [+]
line wrap: on
line diff
--- a/Makefile	Tue Oct 04 18:30:24 2016 -0700
+++ b/Makefile	Tue Oct 04 18:30:49 2016 -0700
@@ -159,6 +159,9 @@
 blastem$(EXE) : $(MAINOBJS)
 	$(CC) -o $@ $^ $(LDFLAGS)
 	$(FIXUP) ./$@
+	
+blastjag$(EXE) : jaguar.o render_sdl.o $(M68KOBJS) $(TRANSOBJS) $(CONFIGOBJS)
+	$(CC) -o $@ $^ $(LDFLAGS)
 
 dis$(EXE) : dis.o 68kinst.o tern.o vos_program_module.o
 	$(CC) -o $@ $^
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jaguar.c	Tue Oct 04 18:30:49 2016 -0700
@@ -0,0 +1,292 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include "m68k_core.h"
+#include "jaguar.h"
+#include "util.h"
+
+//BIOS Area Memory map
+// 10 00 00 - 10 04 00 : Video mode/ Memory control registers
+// 10 04 00 - 10 08 00 : CLUT
+// 10 08 00 - 10 10 00 : Line buffer A
+// 10 10 00 - 10 18 00 : Line buffer B
+// 10 18 00 - 10 20 00 : Write Line buffer
+// 10 21 00 - 10 30 00 : GPU/blitter registers
+// 10 30 00 - 10 40 00 : GPU Local RAM (mirrored every 1K?)
+// 11 00 00 - 11 00 40 : Timer/Clock registers
+// 11 40 00 - 11 40 04 : Joystick Interface
+// 11 A1 00 - 11 A1 52 : DSP/DAC/I2S Registers
+// 11 B0 00 - 11 D0 00 : DSP Local RAM (8KB)
+// 11 D0 00 - 11 E0 00 : Wave table ROM
+
+int headless = 1;
+
+
+void rom0_write_16(uint32_t address, jaguar_context *system, uint16_t value)
+{
+	//TODO: Use write_latch and write_pending to turn two 16-bit writes into a 32-bit one
+	//Documentation heavily suggests that writes to most registers should be 32-bits wide
+	if (address < 0x100000 || address >= 0x120000) {
+		//Boot ROM
+		fprintf(stderr, "Invalid write to Boot ROM - %X:%X\n", address, value);
+		return;
+	}
+	if (address < 0x103000) {
+		if (address < 0x101000) {
+			if (address < 0x100400) {
+				//Video mode / Memory control registers
+				fprintf(stderr, "Unhanelde write to video mode/memory control registers - %X:%X", address, value);
+			} else if (address < 0x100800) {
+				//CLUT
+				address = address >> 1 & 255;
+				system->clut[address] = value;
+			} else {
+				//Line buffer A
+				address = address >> 1 & 0x3FF;
+				if (address < LINEBUFFER_WORDS) {
+					system->line_buffer_a[address] = value;
+				}
+			}
+		} else if (address < 0x101800) {
+			//Line buffer B
+			address = address >> 1 & 0x3FF;
+			if (address < LINEBUFFER_WORDS) {
+				system->line_buffer_b[address] = value;
+			}
+		} else if (address < 0x102100) {
+			//Write Line Buffer
+			address = address >> 1 & 0x3FF;
+			if (address < LINEBUFFER_WORDS) {
+				system->write_line_buffer[address] = value;
+			}
+		} else {
+			//GPU/Blitter registers
+			fprintf(stderr, "Unhandled write to GPU/Blitter registers %X: %X\n", address, value);
+		}
+	} else if (address < 0x11A100) {
+		if (address < 0x110000) {
+			//GPU Local RAM
+			uint32_t offset = address >> 2 & (GPU_RAM_BYTES / sizeof(uint32_t) - 1);
+			uint32_t value32 = value;
+			if (address & 2) {
+				system->gpu_local[offset] &= 0xFFFF0000;
+			} else {
+				system->gpu_local[offset] &= 0x0000FFFF;
+				value32 = value32 << 16;
+			}
+			system->gpu_local[offset] |= value32;
+		} else if (address < 0x114000) {
+			//timer clock registers
+			fprintf(stderr, "Unhanelde write to timer/clock registers - %X:%X", address, value);
+		} else {
+			//joystick interface
+			fprintf(stderr, "Unhanelde write to joystick interface - %X:%X", address, value);
+		}
+	} else if (address < 0x11B000) {
+		//DSP/DAC/I2S Registers
+		fprintf(stderr, "Unhanelde write to DSP/DAC/I2S registers - %X:%X", address, value);
+	} else if (address < 0x11D000) {
+		//DSP local RAM
+		uint32_t offset = address >> 2 & (DSP_RAM_BYTES / sizeof(uint32_t) - 1);
+		uint32_t value32 = value;
+		if (address & 2) {
+			system->dsp_local[offset] &= 0xFFFF0000;
+		} else {
+			system->dsp_local[offset] &= 0x0000FFFF;
+			value32 = value32 << 16;
+		}
+		system->gpu_local[offset] |= value32;
+	} else {
+		//Wave table ROM
+		fprintf(stderr, "Invalid write to wave table ROM - %X:%X\n", address, value);
+	}
+}
+
+uint16_t rom0_read_16(uint32_t address, jaguar_context *system)
+{
+	if (address < 0x100000 || address >= 0x120000) {
+		//Boot ROM
+		address = address >> 1 & ((system->bios_size >> 1) - 1);
+		return system->bios[address];
+	}
+	if (address < 0x103000) {
+		if (address < 0x101000) {
+			if (address < 0x100400) {
+				//Video mode / Memory control registers
+				fprintf(stderr, "Unhandled read from video mode/memory control registers - %X", address);
+			} else if (address < 0x100800) {
+				//CLUT
+				address = address >> 1 & 255;
+				return system->clut[address];
+			} else {
+				//Line buffer A
+				address = address >> 1 & 0x3FF;
+				if (address < LINEBUFFER_WORDS) {
+					return system->line_buffer_a[address];
+				}
+			}
+		} else if (address < 0x101800) {
+			//Line buffer B
+			address = address >> 1 & 0x3FF;
+			if (address < LINEBUFFER_WORDS) {
+				return system->line_buffer_b[address];
+			}
+		} else if (address < 0x102100) {
+			//Write Line Buffer
+			address = address >> 1 & 0x3FF;
+			if (address < LINEBUFFER_WORDS) {
+				return system->write_line_buffer[address];
+			}
+		} else {
+			//GPU/Blitter registers
+			fprintf(stderr, "Unhandled read from GPU/Blitter registers %X\n", address);
+		}
+	} else if (address < 0x11A100) {
+		if (address < 0x110000) {
+			//GPU Local RAM
+			uint32_t offset = address >> 2 & (GPU_RAM_BYTES / sizeof(uint32_t) - 1);
+			if (address & 2) {
+				return system->gpu_local[offset];
+			} else {
+				return system->gpu_local[offset] >> 16;
+			}
+		} else if (address < 0x114000) {
+			//timer clock registers
+			fprintf(stderr, "Unhandled read from timer/clock registers - %X", address);
+		} else {
+			//joystick interface
+			fprintf(stderr, "Unhandled read from joystick interface - %X", address);
+		}
+	} else if (address < 0x11B000) {
+		//DSP/DAC/I2S Registers
+		fprintf(stderr, "Unhandled read from DSP/DAC/I2S registers - %X", address);
+	} else if (address < 0x11D000) {
+		//DSP local RAM
+		uint32_t offset = address >> 2 & (DSP_RAM_BYTES / sizeof(uint32_t) - 1);
+		if (address & 2) {
+				return system->dsp_local[offset];
+			} else {
+				return system->dsp_local[offset] >> 16;
+			}
+	} else {
+		//Wave table ROM
+		fprintf(stderr, "Unhandled read from wave table ROM - %X\n", address);
+	}
+	return 0xFFFF;
+}
+
+
+void *rom0_write_m68k(uint32_t address, void *context, uint16_t value)
+{
+	rom0_write_16(address, ((m68k_context *)context)->system, value);
+	return context;
+}
+
+uint16_t rom0_read_m68k(uint32_t address, void *context)
+{
+	return rom0_read_16(address, ((m68k_context *)context)->system);
+}
+
+void *rom0_write_m68k_b(uint32_t address, void *context, uint8_t value)
+{
+	//seems unlikely these areas support byte access
+	uint16_t value16 = value;
+	value16 |= value16 << 8;
+	rom0_write_16(address, ((m68k_context *)context)->system, value16);
+	return context;
+}
+
+uint8_t rom0_read_m68k_b(uint32_t address, void *context)
+{
+	uint16_t value = rom0_read_16(address, ((m68k_context *)context)->system);
+	if (address & 1) {
+		return value;
+	}
+	return value >> 8;
+}
+
+m68k_context * sync_components(m68k_context * context, uint32_t address)
+{
+	if (context->current_cycle > 0x10000000) {
+		context->current_cycle -= 0x10000000;
+	}
+	return context;
+}
+
+jaguar_context *init_jaguar(uint16_t *bios, uint32_t bios_size, uint16_t *cart, uint32_t cart_size)
+{
+	jaguar_context *system = calloc(1, sizeof(jaguar_context));
+	system->bios = bios;
+	system->bios_size = bios_size;
+	system->cart = cart;
+	system->cart_size = cart_size;
+
+	memmap_chunk jag_m68k_map[8];
+	for (uint32_t start = 0, index=0; index < 8; index++, start += 0x200000)
+	{
+		jag_m68k_map[index].start = start;
+		jag_m68k_map[index].end = start + 0x200000;
+		jag_m68k_map[index].mask = index ? 0x1FFFFF : 0xFFFFFF;
+		jag_m68k_map[index].aux_mask = bios_size - 1;
+		jag_m68k_map[index].ptr_index = index;
+		jag_m68k_map[index].flags = MMAP_READ | MMAP_WRITE | MMAP_PTR_IDX | MMAP_FUNC_NULL | MMAP_AUX_BUFF;
+		jag_m68k_map[index].buffer = bios;
+		jag_m68k_map[index].read_16 = rom0_read_m68k;
+		jag_m68k_map[index].read_8 = rom0_read_m68k_b;
+		jag_m68k_map[index].write_16 = rom0_write_m68k;
+		jag_m68k_map[index].write_8 = rom0_write_m68k_b;
+	}
+	m68k_options *opts = malloc(sizeof(m68k_options));
+	init_m68k_opts(opts, jag_m68k_map, 8, 2);
+	system->m68k = init_68k_context(opts);
+	system->m68k->system = system;
+	return system;
+}
+
+//modified copy of the version in blastem.c
+uint16_t *load_rom(char * filename, uint32_t *size)
+{
+	FILE * f = fopen(filename, "rb");
+	if (!f) {
+		return 0;
+	}
+	fseek(f, 0, SEEK_END);
+	long filesize = ftell(f);
+	fseek(f, 0, SEEK_SET);
+	
+	*size = nearest_pow2(filesize);
+	uint16_t *cart = malloc(*size);
+	if (filesize != fread(cart, 1, filesize, f)) {
+		fatal_error("Error reading from %s\n", filename);
+	}
+	while (filesize < *size)
+	{
+		cart[filesize / 2] = 0xFFFF;
+		filesize += 2;
+	}
+	fclose(f);
+	return cart;
+}
+
+//temporary main function until I clean up blastem.c
+int main(int argc, char **argv)
+{
+	if (argc < 3) {
+		fputs("Usage: blastjag BIOS ROM\n", stderr);
+		return 1;
+	}
+	uint32_t bios_size;
+	uint16_t *bios = load_rom(argv[1], &bios_size);
+	if (!bios_size) {
+		fatal_error("Failed to read BIOS from %s\n", argv[1]);
+	}
+	uint32_t cart_size;
+	uint16_t *cart = load_rom(argv[2], &cart_size);
+	if (!bios_size) {
+		fatal_error("Failed to read cart from %s\n", argv[2]);
+	}
+	jaguar_context *system = init_jaguar(bios, bios_size, cart, cart_size);
+	m68k_reset(system->m68k);
+	return 0;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jaguar.h	Tue Oct 04 18:30:49 2016 -0700
@@ -0,0 +1,31 @@
+#ifndef JAGUAR_H_
+#define JAGUAR_H_
+
+#define DRAM_WORDS (4*1024*1024)
+#define LINEBUFFER_WORDS 720
+#define GPU_RAM_BYTES 4096
+#define DSP_RAM_BYTES 8192
+
+typedef struct {
+	m68k_context *m68k;
+	uint16_t     *bios;
+	uint16_t     *cart;
+	uint32_t     bios_size;
+	uint32_t     cart_size;
+	uint32_t     memcon;
+	uint16_t     write_latch;
+	uint8_t      write_pending;
+	
+	uint16_t     dram[DRAM_WORDS];
+	uint32_t     gpu_local[GPU_RAM_BYTES / sizeof(uint32_t)];
+	uint32_t     dsp_local[DSP_RAM_BYTES / sizeof(uint32_t)];
+	uint16_t     clut[256];
+	uint16_t     line_buffer_a[LINEBUFFER_WORDS];
+	uint16_t     line_buffer_b[LINEBUFFER_WORDS];
+	uint16_t     *write_line_buffer;
+	uint16_t     *read_line_buffer;
+	
+} jaguar_context;
+
+
+#endif //JAGUAR_H_