hw/block/tc58128.c

   1 /*
   2  * TC58128 NAND EEPROM emulation
   3  *
   4  * Copyright (c) 2005 Samuel Tardieu
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice (including the next
  14  * paragraph) shall be included in all copies or substantial portions of the
  15  * Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  *
  25  * SPDX-License-Identifier: MIT
  26  */
  27 #include "qemu/osdep.h"
  28 #include "qemu/units.h"
  29 #include "hw/sh4/sh.h"
  30 #include "hw/loader.h"
  31 #include "sysemu/qtest.h"
  32 #include "qemu/error-report.h"
  33
  34 #define CE1  0x0100
  35 #define CE2  0x0200
  36 #define RE   0x0400
  37 #define WE   0x0800
  38 #define ALE  0x1000
  39 #define CLE  0x2000
  40 #define RDY1 0x4000
  41 #define RDY2 0x8000
  42 #define RDY(n) ((n) == 0 ? RDY1 : RDY2)
  43
  44 typedef enum { WAIT, READ1, READ2, READ3 } state_t;
  45
  46 typedef struct {
  47     uint8_t *flash_contents;
  48     state_t state;
  49     uint32_t address;
  50     uint8_t address_cycle;
  51 } tc58128_dev;
  52
  53 static tc58128_dev tc58128_devs[2];
  54
  55 #define FLASH_SIZE (16 * MiB)
  56
  57 static void init_dev(tc58128_dev * dev, const char *filename)
  58 {
  59     int ret, blocks;
  60
  61     dev->state = WAIT;
  62     dev->flash_contents = g_malloc(FLASH_SIZE);
  63     memset(dev->flash_contents, 0xff, FLASH_SIZE);
  64     if (filename) {
  65         /* Load flash image skipping the first block */
  66         ret = load_image_size(filename, dev->flash_contents + 528 * 32,
  67                               FLASH_SIZE - 528 * 32);
  68         if (ret < 0) {
  69             if (!qtest_enabled()) {
  70                 error_report("Could not load flash image %s", filename);
  71                 exit(1);
  72             }
  73         } else {
  74             /* Build first block with number of blocks */
  75             blocks = DIV_ROUND_UP(ret, 528 * 32);
  76             dev->flash_contents[0] = blocks & 0xff;
  77             dev->flash_contents[1] = (blocks >> 8) & 0xff;
  78             dev->flash_contents[2] = (blocks >> 16) & 0xff;
  79             dev->flash_contents[3] = (blocks >> 24) & 0xff;
  80             fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
  81                     filename);
  82         }
  83     }
  84 }
  85
  86 static void handle_command(tc58128_dev * dev, uint8_t command)
  87 {
  88     switch (command) {
  89     case 0xff:
  90         fprintf(stderr, "reset flash device\n");
  91         dev->state = WAIT;
  92         break;
  93     case 0x00:
  94         fprintf(stderr, "read mode 1\n");
  95         dev->state = READ1;
  96         dev->address_cycle = 0;
  97         break;
  98     case 0x01:
  99         fprintf(stderr, "read mode 2\n");
 100         dev->state = READ2;
 101         dev->address_cycle = 0;
 102         break;
 103     case 0x50:
 104         fprintf(stderr, "read mode 3\n");
 105         dev->state = READ3;
 106         dev->address_cycle = 0;
 107         break;
 108     default:
 109         fprintf(stderr, "unknown flash command 0x%02x\n", command);
 110         abort();
 111     }
 112 }
 113
 114 static void handle_address(tc58128_dev * dev, uint8_t data)
 115 {
 116     switch (dev->state) {
 117     case READ1:
 118     case READ2:
 119     case READ3:
 120         switch (dev->address_cycle) {
 121         case 0:
 122             dev->address = data;
 123             if (dev->state == READ2)
 124                 dev->address |= 0x100;
 125             else if (dev->state == READ3)
 126                 dev->address |= 0x200;
 127             break;
 128         case 1:
 129             dev->address += data * 528 * 0x100;
 130             break;
 131         case 2:
 132             dev->address += data * 528;
 133             fprintf(stderr, "address pointer in flash: 0x%08x\n",
 134                     dev->address);
 135             break;
 136         default:
 137             /* Invalid data */
 138             abort();
 139         }
 140         dev->address_cycle++;
 141         break;
 142     default:
 143         abort();
 144     }
 145 }
 146
 147 static uint8_t handle_read(tc58128_dev * dev)
 148 {
 149 #if 0
 150     if (dev->address % 0x100000 == 0)
 151         fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
 152 #endif
 153     return dev->flash_contents[dev->address++];
 154 }
 155
 156 /* We never mark the device as busy, so interrupts cannot be triggered
 157    XXXXX */
 158
 159 static int tc58128_cb(uint16_t porta, uint16_t portb,
 160                       uint16_t * periph_pdtra, uint16_t * periph_portadir,
 161                       uint16_t * periph_pdtrb, uint16_t * periph_portbdir)
 162 {
 163     int dev;
 164
 165     if ((porta & CE1) == 0)
 166         dev = 0;
 167     else if ((porta & CE2) == 0)
 168         dev = 1;
 169     else
 170         return 0;        /* No device selected */
 171
 172     if ((porta & RE) && (porta & WE)) {
 173         /* Nothing to do, assert ready and return to input state */
 174         *periph_portadir &= 0xff00;
 175         *periph_portadir |= RDY(dev);
 176         *periph_pdtra |= RDY(dev);
 177         return 1;
 178     }
 179
 180     if (porta & CLE) {
 181         /* Command */
 182         assert((porta & WE) == 0);
 183         handle_command(&tc58128_devs[dev], porta & 0x00ff);
 184     } else if (porta & ALE) {
 185         assert((porta & WE) == 0);
 186         handle_address(&tc58128_devs[dev], porta & 0x00ff);
 187     } else if ((porta & RE) == 0) {
 188         *periph_portadir |= 0x00ff;
 189         *periph_pdtra &= 0xff00;
 190         *periph_pdtra |= handle_read(&tc58128_devs[dev]);
 191     } else {
 192         abort();
 193     }
 194     return 1;
 195 }
 196
 197 static sh7750_io_device tc58128 = {
 198     RE | WE,            /* Port A triggers */
 199     0,                  /* Port B triggers */
 200     tc58128_cb          /* Callback */
 201 };
 202
 203 int tc58128_init(struct SH7750State *s, const char *zone1, const char *zone2)
 204 {
 205     init_dev(&tc58128_devs[0], zone1);
 206     init_dev(&tc58128_devs[1], zone2);
 207     return sh7750_register_io_device(s, &tc58128);
 208 }