view x86_backend.h @ 478:2e4a4188cfb0

Fix DMA fill so that it does not cause observable changes to the FIFO. Get DMA copy mostly correct from an observable ffect perspective. DMA copy probably does not reflect internal implementation still given that evidence seems to suggest no FIFO usage at all.
author Mike Pavone <pavone@retrodev.com>
date Tue, 17 Sep 2013 00:11:45 -0700
parents 140af5509ce7
children 5af986d2b9da
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/*
 Copyright 2013 Michael Pavone
 This file is part of BlastEm. 
 BlastEm is free software distributed under the terms of the GNU General Public License version 3 or greater. See COPYING for full license text.
*/
#ifndef X86_BACKEND_H_
#define X86_BACKEND_H_

#include <stdint.h>

#define INVALID_OFFSET 0xFFFFFFFF
#define EXTENSION_WORD 0xFFFFFFFE

typedef struct {
	int32_t disp;
	uint8_t mode;
	uint8_t base;
	uint8_t index;
	uint8_t cycles;
} x86_ea;

typedef struct {
	uint8_t  *base;
	int32_t  *offsets;
} native_map_slot;

typedef struct deferred_addr {
	struct deferred_addr *next;
	uint8_t              *dest;
	uint32_t             address;
} deferred_addr;


#define MMAP_READ      0x01
#define MMAP_WRITE     0x02
#define MMAP_CODE      0x04
#define MMAP_PTR_IDX   0x08
#define MMAP_ONLY_ODD  0x10
#define MMAP_ONLY_EVEN 0x20
#define MMAP_FUNC_NULL 0x40

typedef uint16_t (*read_16_fun)(uint32_t address, void * context);
typedef uint8_t (*read_8_fun)(uint32_t address, void * context);
typedef void * (*write_16_fun)(uint32_t address, void * context, uint16_t value);
typedef void * (*write_8_fun)(uint32_t address, void * context, uint8_t value);

typedef struct {
	uint32_t     start;
	uint32_t     end;
	uint32_t     mask;
	uint16_t     ptr_index;
	uint16_t     flags;
	void *       buffer;
	read_16_fun  read_16;
	write_16_fun write_16;
	read_8_fun   read_8;
	write_8_fun  write_8;
} memmap_chunk;

typedef uint8_t * (*native_addr_func)(void * context, uint32_t address);

deferred_addr * defer_address(deferred_addr * old_head, uint32_t address, uint8_t *dest);
void remove_deferred_until(deferred_addr **head_ptr, deferred_addr * remove_to);
void process_deferred(deferred_addr ** head_ptr, void * context, native_addr_func get_native);

#endif //X86_BACKEND_H_