root / hw / tc58128.c @ 50d3eeae
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#include <assert.h> |
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#include "vl.h" |
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#define CE1 0x0100 |
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#define CE2 0x0200 |
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#define RE 0x0400 |
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#define WE 0x0800 |
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#define ALE 0x1000 |
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#define CLE 0x2000 |
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#define RDY1 0x4000 |
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#define RDY2 0x8000 |
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#define RDY(n) ((n) == 0 ? RDY1 : RDY2) |
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typedef enum { WAIT, READ1, READ2, READ3 } state_t; |
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typedef struct { |
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uint8_t *flash_contents; |
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state_t state; |
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uint32_t address; |
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uint8_t address_cycle; |
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} tc58128_dev; |
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static tc58128_dev tc58128_devs[2]; |
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#define FLASH_SIZE (16*1024*1024) |
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void init_dev(tc58128_dev * dev, char *filename) |
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{ |
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int ret, blocks;
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dev->state = WAIT; |
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dev->flash_contents = qemu_mallocz(FLASH_SIZE); |
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memset(dev->flash_contents, 0xff, FLASH_SIZE);
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if (!dev->flash_contents) {
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fprintf(stderr, "could not alloc memory for flash\n");
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exit(1);
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} |
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if (filename) {
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/* Load flash image skipping the first block */
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ret = load_image(filename, dev->flash_contents + 528 * 32); |
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if (ret < 0) { |
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fprintf(stderr, "ret=%d\n", ret);
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fprintf(stderr, "qemu: could not load flash image %s\n",
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filename); |
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exit(1);
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} else {
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/* Build first block with number of blocks */
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blocks = (ret + 528 * 32 - 1) / (528 * 32); |
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dev->flash_contents[0] = blocks & 0xff; |
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dev->flash_contents[1] = (blocks >> 8) & 0xff; |
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dev->flash_contents[2] = (blocks >> 16) & 0xff; |
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dev->flash_contents[3] = (blocks >> 24) & 0xff; |
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fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
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filename); |
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} |
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} |
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} |
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|
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void handle_command(tc58128_dev * dev, uint8_t command)
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{ |
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switch (command) {
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case 0xff: |
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fprintf(stderr, "reset flash device\n");
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dev->state = WAIT; |
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break;
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case 0x00: |
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fprintf(stderr, "read mode 1\n");
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dev->state = READ1; |
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dev->address_cycle = 0;
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break;
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case 0x01: |
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fprintf(stderr, "read mode 2\n");
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dev->state = READ2; |
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dev->address_cycle = 0;
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break;
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case 0x50: |
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fprintf(stderr, "read mode 3\n");
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dev->state = READ3; |
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dev->address_cycle = 0;
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break;
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default:
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fprintf(stderr, "unknown flash command 0x%02x\n", command);
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assert(0);
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} |
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} |
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void handle_address(tc58128_dev * dev, uint8_t data)
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{ |
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switch (dev->state) {
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case READ1:
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case READ2:
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case READ3:
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switch (dev->address_cycle) {
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case 0: |
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dev->address = data; |
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if (dev->state == READ2)
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dev->address |= 0x100;
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else if (dev->state == READ3) |
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dev->address |= 0x200;
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break;
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case 1: |
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dev->address += data * 528 * 0x100; |
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break;
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case 2: |
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dev->address += data * 528;
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fprintf(stderr, "address pointer in flash: 0x%08x\n",
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dev->address); |
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break;
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default:
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/* Invalid data */
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assert(0);
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} |
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dev->address_cycle++; |
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break;
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default:
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assert(0);
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} |
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} |
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uint8_t handle_read(tc58128_dev * dev) |
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{ |
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#if 0
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if (dev->address % 0x100000 == 0)
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fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
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#endif
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return dev->flash_contents[dev->address++];
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} |
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/* We never mark the device as busy, so interrupts cannot be triggered
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XXXXX */
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int tc58128_cb(uint16_t porta, uint16_t portb,
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uint16_t * periph_pdtra, uint16_t * periph_portadir, |
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uint16_t * periph_pdtrb, uint16_t * periph_portbdir) |
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{ |
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int dev;
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if ((porta & CE1) == 0) |
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dev = 0;
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else if ((porta & CE2) == 0) |
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dev = 1;
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else
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return 0; /* No device selected */ |
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if ((porta & RE) && (porta & WE)) {
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/* Nothing to do, assert ready and return to input state */
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*periph_portadir &= 0xff00;
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*periph_portadir |= RDY(dev); |
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*periph_pdtra |= RDY(dev); |
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return 1; |
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} |
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if (porta & CLE) {
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/* Command */
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assert((porta & WE) == 0);
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handle_command(&tc58128_devs[dev], porta & 0x00ff);
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} else if (porta & ALE) { |
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assert((porta & WE) == 0);
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handle_address(&tc58128_devs[dev], porta & 0x00ff);
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} else if ((porta & RE) == 0) { |
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*periph_portadir |= 0x00ff;
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*periph_pdtra &= 0xff00;
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*periph_pdtra |= handle_read(&tc58128_devs[dev]); |
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} else {
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assert(0);
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} |
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return 1; |
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} |
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static sh7750_io_device tc58128 = {
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RE | WE, /* Port A triggers */
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0, /* Port B triggers */ |
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tc58128_cb /* Callback */
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}; |
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int tc58128_init(struct SH7750State *s, char *zone1, char *zone2) |
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{ |
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init_dev(&tc58128_devs[0], zone1);
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init_dev(&tc58128_devs[1], zone2);
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return sh7750_register_io_device(s, &tc58128);
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} |