qemu/hw/block/tc58128.c
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   1#include "qemu/osdep.h"
   2#include "qemu/units.h"
   3#include "hw/sh4/sh.h"
   4#include "hw/loader.h"
   5#include "sysemu/qtest.h"
   6#include "qemu/error-report.h"
   7
   8#define CE1  0x0100
   9#define CE2  0x0200
  10#define RE   0x0400
  11#define WE   0x0800
  12#define ALE  0x1000
  13#define CLE  0x2000
  14#define RDY1 0x4000
  15#define RDY2 0x8000
  16#define RDY(n) ((n) == 0 ? RDY1 : RDY2)
  17
  18typedef enum { WAIT, READ1, READ2, READ3 } state_t;
  19
  20typedef struct {
  21    uint8_t *flash_contents;
  22    state_t state;
  23    uint32_t address;
  24    uint8_t address_cycle;
  25} tc58128_dev;
  26
  27static tc58128_dev tc58128_devs[2];
  28
  29#define FLASH_SIZE (16 * MiB)
  30
  31static void init_dev(tc58128_dev * dev, const char *filename)
  32{
  33    int ret, blocks;
  34
  35    dev->state = WAIT;
  36    dev->flash_contents = g_malloc(FLASH_SIZE);
  37    memset(dev->flash_contents, 0xff, FLASH_SIZE);
  38    if (filename) {
  39        /* Load flash image skipping the first block */
  40        ret = load_image_size(filename, dev->flash_contents + 528 * 32,
  41                              FLASH_SIZE - 528 * 32);
  42        if (ret < 0) {
  43            if (!qtest_enabled()) {
  44                error_report("Could not load flash image %s", filename);
  45                exit(1);
  46            }
  47        } else {
  48            /* Build first block with number of blocks */
  49            blocks = DIV_ROUND_UP(ret, 528 * 32);
  50            dev->flash_contents[0] = blocks & 0xff;
  51            dev->flash_contents[1] = (blocks >> 8) & 0xff;
  52            dev->flash_contents[2] = (blocks >> 16) & 0xff;
  53            dev->flash_contents[3] = (blocks >> 24) & 0xff;
  54            fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
  55                    filename);
  56        }
  57    }
  58}
  59
  60static void handle_command(tc58128_dev * dev, uint8_t command)
  61{
  62    switch (command) {
  63    case 0xff:
  64        fprintf(stderr, "reset flash device\n");
  65        dev->state = WAIT;
  66        break;
  67    case 0x00:
  68        fprintf(stderr, "read mode 1\n");
  69        dev->state = READ1;
  70        dev->address_cycle = 0;
  71        break;
  72    case 0x01:
  73        fprintf(stderr, "read mode 2\n");
  74        dev->state = READ2;
  75        dev->address_cycle = 0;
  76        break;
  77    case 0x50:
  78        fprintf(stderr, "read mode 3\n");
  79        dev->state = READ3;
  80        dev->address_cycle = 0;
  81        break;
  82    default:
  83        fprintf(stderr, "unknown flash command 0x%02x\n", command);
  84        abort();
  85    }
  86}
  87
  88static void handle_address(tc58128_dev * dev, uint8_t data)
  89{
  90    switch (dev->state) {
  91    case READ1:
  92    case READ2:
  93    case READ3:
  94        switch (dev->address_cycle) {
  95        case 0:
  96            dev->address = data;
  97            if (dev->state == READ2)
  98                dev->address |= 0x100;
  99            else if (dev->state == READ3)
 100                dev->address |= 0x200;
 101            break;
 102        case 1:
 103            dev->address += data * 528 * 0x100;
 104            break;
 105        case 2:
 106            dev->address += data * 528;
 107            fprintf(stderr, "address pointer in flash: 0x%08x\n",
 108                    dev->address);
 109            break;
 110        default:
 111            /* Invalid data */
 112            abort();
 113        }
 114        dev->address_cycle++;
 115        break;
 116    default:
 117        abort();
 118    }
 119}
 120
 121static uint8_t handle_read(tc58128_dev * dev)
 122{
 123#if 0
 124    if (dev->address % 0x100000 == 0)
 125        fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
 126#endif
 127    return dev->flash_contents[dev->address++];
 128}
 129
 130/* We never mark the device as busy, so interrupts cannot be triggered
 131   XXXXX */
 132
 133static int tc58128_cb(uint16_t porta, uint16_t portb,
 134                      uint16_t * periph_pdtra, uint16_t * periph_portadir,
 135                      uint16_t * periph_pdtrb, uint16_t * periph_portbdir)
 136{
 137    int dev;
 138
 139    if ((porta & CE1) == 0)
 140        dev = 0;
 141    else if ((porta & CE2) == 0)
 142        dev = 1;
 143    else
 144        return 0;               /* No device selected */
 145
 146    if ((porta & RE) && (porta & WE)) {
 147        /* Nothing to do, assert ready and return to input state */
 148        *periph_portadir &= 0xff00;
 149        *periph_portadir |= RDY(dev);
 150        *periph_pdtra |= RDY(dev);
 151        return 1;
 152    }
 153
 154    if (porta & CLE) {
 155        /* Command */
 156        assert((porta & WE) == 0);
 157        handle_command(&tc58128_devs[dev], porta & 0x00ff);
 158    } else if (porta & ALE) {
 159        assert((porta & WE) == 0);
 160        handle_address(&tc58128_devs[dev], porta & 0x00ff);
 161    } else if ((porta & RE) == 0) {
 162        *periph_portadir |= 0x00ff;
 163        *periph_pdtra &= 0xff00;
 164        *periph_pdtra |= handle_read(&tc58128_devs[dev]);
 165    } else {
 166        abort();
 167    }
 168    return 1;
 169}
 170
 171static sh7750_io_device tc58128 = {
 172    RE | WE,                    /* Port A triggers */
 173    0,                          /* Port B triggers */
 174    tc58128_cb                  /* Callback */
 175};
 176
 177int tc58128_init(struct SH7750State *s, const char *zone1, const char *zone2)
 178{
 179    init_dev(&tc58128_devs[0], zone1);
 180    init_dev(&tc58128_devs[1], zone2);
 181    return sh7750_register_io_device(s, &tc58128);
 182}
 183