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#include "hw.h"
#include "sh.h"
#include "sysemu.h"
#include "loader.h"
#define CE1 0x0100
#define CE2 0x0200
#define RE 0x0400
#define WE 0x0800
#define ALE 0x1000
#define CLE 0x2000
#define RDY1 0x4000
#define RDY2 0x8000
#define RDY(n) ((n) == 0 ? RDY1 : RDY2)
typedef enum { WAIT, READ1, READ2, READ3 } state_t;
typedef struct {
uint8_t *flash_contents;
state_t state;
uint32_t address;
uint8_t address_cycle;
} tc58128_dev;
static tc58128_dev tc58128_devs[2];
#define FLASH_SIZE (16*1024*1024)
static void init_dev(tc58128_dev * dev, const char *filename)
{
int ret, blocks;
dev->state = WAIT;
dev->flash_contents = qemu_mallocz(FLASH_SIZE);
memset(dev->flash_contents, 0xff, FLASH_SIZE);
if (!dev->flash_contents) {
fprintf(stderr, "could not alloc memory for flash\n");
exit(1);
}
if (filename) {
/* Load flash image skipping the first block */
ret = load_image(filename, dev->flash_contents + 528 * 32);
if (ret < 0) {
fprintf(stderr, "ret=%d\n", ret);
fprintf(stderr, "qemu: could not load flash image %s\n",
filename);
exit(1);
} else {
/* Build first block with number of blocks */
blocks = (ret + 528 * 32 - 1) / (528 * 32);
dev->flash_contents[0] = blocks & 0xff;
dev->flash_contents[1] = (blocks >> 8) & 0xff;
dev->flash_contents[2] = (blocks >> 16) & 0xff;
dev->flash_contents[3] = (blocks >> 24) & 0xff;
fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
filename);
}
}
}
static void handle_command(tc58128_dev * dev, uint8_t command)
{
switch (command) {
case 0xff:
fprintf(stderr, "reset flash device\n");
dev->state = WAIT;
break;
case 0x00:
fprintf(stderr, "read mode 1\n");
dev->state = READ1;
dev->address_cycle = 0;
break;
case 0x01:
fprintf(stderr, "read mode 2\n");
dev->state = READ2;
dev->address_cycle = 0;
break;
case 0x50:
fprintf(stderr, "read mode 3\n");
dev->state = READ3;
dev->address_cycle = 0;
break;
default:
fprintf(stderr, "unknown flash command 0x%02x\n", command);
abort();
}
}
static void handle_address(tc58128_dev * dev, uint8_t data)
{
switch (dev->state) {
case READ1:
case READ2:
case READ3:
switch (dev->address_cycle) {
case 0:
dev->address = data;
if (dev->state == READ2)
dev->address |= 0x100;
else if (dev->state == READ3)
dev->address |= 0x200;
break;
case 1:
dev->address += data * 528 * 0x100;
break;
case 2:
dev->address += data * 528;
fprintf(stderr, "address pointer in flash: 0x%08x\n",
dev->address);
break;
default:
/* Invalid data */
abort();
}
dev->address_cycle++;
break;
default:
abort();
}
}
static uint8_t handle_read(tc58128_dev * dev)
{
#if 0
if (dev->address % 0x100000 == 0)
fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
#endif
return dev->flash_contents[dev->address++];
}
/* We never mark the device as busy, so interrupts cannot be triggered
XXXXX */
static int tc58128_cb(uint16_t porta, uint16_t portb,
uint16_t * periph_pdtra, uint16_t * periph_portadir,
uint16_t * periph_pdtrb, uint16_t * periph_portbdir)
{
int dev;
if ((porta & CE1) == 0)
dev = 0;
else if ((porta & CE2) == 0)
dev = 1;
else
return 0; /* No device selected */
if ((porta & RE) && (porta & WE)) {
/* Nothing to do, assert ready and return to input state */
*periph_portadir &= 0xff00;
*periph_portadir |= RDY(dev);
*periph_pdtra |= RDY(dev);
return 1;
}
if (porta & CLE) {
/* Command */
assert((porta & WE) == 0);
handle_command(&tc58128_devs[dev], porta & 0x00ff);
} else if (porta & ALE) {
assert((porta & WE) == 0);
handle_address(&tc58128_devs[dev], porta & 0x00ff);
} else if ((porta & RE) == 0) {
*periph_portadir |= 0x00ff;
*periph_pdtra &= 0xff00;
*periph_pdtra |= handle_read(&tc58128_devs[dev]);
} else {
abort();
}
return 1;
}
static sh7750_io_device tc58128 = {
RE | WE, /* Port A triggers */
0, /* Port B triggers */
tc58128_cb /* Callback */
};
int tc58128_init(struct SH7750State *s, const char *zone1, const char *zone2)
{
init_dev(&tc58128_devs[0], zone1);
init_dev(&tc58128_devs[1], zone2);
return sh7750_register_io_device(s, &tc58128);
}
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