i2c_eeprom_emul.c 5.1 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206
  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * Simulate an I2C eeprom
  4. *
  5. * Copyright (c) 2014 Google, Inc
  6. */
  7. #include <common.h>
  8. #include <dm.h>
  9. #include <errno.h>
  10. #include <i2c.h>
  11. #include <log.h>
  12. #include <malloc.h>
  13. #include <asm/test.h>
  14. #ifdef DEBUG
  15. #define debug_buffer print_buffer
  16. #else
  17. #define debug_buffer(x, ...)
  18. #endif
  19. struct sandbox_i2c_flash_plat_data {
  20. enum sandbox_i2c_eeprom_test_mode test_mode;
  21. const char *filename;
  22. int offset_len; /* Length of an offset in bytes */
  23. int size; /* Size of data buffer */
  24. uint chip_addr_offset_mask; /* mask of addr bits used for offset */
  25. };
  26. struct sandbox_i2c_flash {
  27. uint8_t *data;
  28. uint prev_addr; /* slave address of previous access */
  29. uint prev_offset; /* offset of previous access */
  30. };
  31. void sandbox_i2c_eeprom_set_test_mode(struct udevice *dev,
  32. enum sandbox_i2c_eeprom_test_mode mode)
  33. {
  34. struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev);
  35. plat->test_mode = mode;
  36. }
  37. void sandbox_i2c_eeprom_set_offset_len(struct udevice *dev, int offset_len)
  38. {
  39. struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev);
  40. plat->offset_len = offset_len;
  41. }
  42. void sandbox_i2c_eeprom_set_chip_addr_offset_mask(struct udevice *dev,
  43. uint mask)
  44. {
  45. struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev);
  46. plat->chip_addr_offset_mask = mask;
  47. }
  48. uint sanbox_i2c_eeprom_get_prev_addr(struct udevice *dev)
  49. {
  50. struct sandbox_i2c_flash *priv = dev_get_priv(dev);
  51. return priv->prev_addr;
  52. }
  53. uint sanbox_i2c_eeprom_get_prev_offset(struct udevice *dev)
  54. {
  55. struct sandbox_i2c_flash *priv = dev_get_priv(dev);
  56. return priv->prev_offset;
  57. }
  58. static int sandbox_i2c_eeprom_xfer(struct udevice *emul, struct i2c_msg *msg,
  59. int nmsgs)
  60. {
  61. struct sandbox_i2c_flash *priv = dev_get_priv(emul);
  62. struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(emul);
  63. uint offset = msg->addr & plat->chip_addr_offset_mask;
  64. debug("\n%s\n", __func__);
  65. debug_buffer(0, priv->data, 1, 16, 0);
  66. /* store addr for testing visibity */
  67. priv->prev_addr = msg->addr;
  68. for (; nmsgs > 0; nmsgs--, msg++) {
  69. int len;
  70. u8 *ptr;
  71. if (!plat->size)
  72. return -ENODEV;
  73. len = msg->len;
  74. debug(" %s: msg->addr=%x msg->len=%d",
  75. msg->flags & I2C_M_RD ? "read" : "write",
  76. msg->addr, msg->len);
  77. if (msg->flags & I2C_M_RD) {
  78. if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE)
  79. len = 1;
  80. debug(", offset %x, len %x: ", offset, len);
  81. if (offset + len > plat->size) {
  82. int overflow = offset + len - plat->size;
  83. int initial = len - overflow;
  84. memcpy(msg->buf, priv->data + offset, initial);
  85. memcpy(msg->buf + initial, priv->data,
  86. overflow);
  87. } else {
  88. memcpy(msg->buf, priv->data + offset, len);
  89. }
  90. memset(msg->buf + len, '\xff', msg->len - len);
  91. debug_buffer(0, msg->buf, 1, msg->len, 0);
  92. } else if (len >= plat->offset_len) {
  93. int i;
  94. ptr = msg->buf;
  95. for (i = 0; i < plat->offset_len; i++, len--)
  96. offset = (offset << 8) | *ptr++;
  97. debug(", set offset %x: ", offset);
  98. debug_buffer(0, msg->buf, 1, msg->len, 0);
  99. if (plat->test_mode == SIE_TEST_MODE_SINGLE_BYTE)
  100. len = min(len, 1);
  101. /* store offset for testing visibility */
  102. priv->prev_offset = offset;
  103. /* For testing, map offsets into our limited buffer.
  104. * offset wraps every 256 bytes
  105. */
  106. offset &= 0xff;
  107. debug("mapped offset to %x\n", offset);
  108. if (offset + len > plat->size) {
  109. int overflow = offset + len - plat->size;
  110. int initial = len - overflow;
  111. memcpy(priv->data + offset, ptr, initial);
  112. memcpy(priv->data, ptr + initial, overflow);
  113. } else {
  114. memcpy(priv->data + offset, ptr, len);
  115. }
  116. }
  117. }
  118. debug_buffer(0, priv->data, 1, 16, 0);
  119. return 0;
  120. }
  121. struct dm_i2c_ops sandbox_i2c_emul_ops = {
  122. .xfer = sandbox_i2c_eeprom_xfer,
  123. };
  124. static int sandbox_i2c_eeprom_ofdata_to_platdata(struct udevice *dev)
  125. {
  126. struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev);
  127. plat->size = dev_read_u32_default(dev, "sandbox,size", 32);
  128. plat->filename = dev_read_string(dev, "sandbox,filename");
  129. if (!plat->filename) {
  130. debug("%s: No filename for device '%s'\n", __func__,
  131. dev->name);
  132. return -EINVAL;
  133. }
  134. plat->test_mode = SIE_TEST_MODE_NONE;
  135. plat->offset_len = 1;
  136. plat->chip_addr_offset_mask = 0;
  137. return 0;
  138. }
  139. static int sandbox_i2c_eeprom_probe(struct udevice *dev)
  140. {
  141. struct sandbox_i2c_flash_plat_data *plat = dev_get_platdata(dev);
  142. struct sandbox_i2c_flash *priv = dev_get_priv(dev);
  143. priv->data = calloc(1, plat->size);
  144. if (!priv->data)
  145. return -ENOMEM;
  146. return 0;
  147. }
  148. static int sandbox_i2c_eeprom_remove(struct udevice *dev)
  149. {
  150. struct sandbox_i2c_flash *priv = dev_get_priv(dev);
  151. free(priv->data);
  152. return 0;
  153. }
  154. static const struct udevice_id sandbox_i2c_ids[] = {
  155. { .compatible = "sandbox,i2c-eeprom" },
  156. { }
  157. };
  158. U_BOOT_DRIVER(sandbox_i2c_emul) = {
  159. .name = "sandbox_i2c_eeprom_emul",
  160. .id = UCLASS_I2C_EMUL,
  161. .of_match = sandbox_i2c_ids,
  162. .ofdata_to_platdata = sandbox_i2c_eeprom_ofdata_to_platdata,
  163. .probe = sandbox_i2c_eeprom_probe,
  164. .remove = sandbox_i2c_eeprom_remove,
  165. .priv_auto_alloc_size = sizeof(struct sandbox_i2c_flash),
  166. .platdata_auto_alloc_size = sizeof(struct sandbox_i2c_flash_plat_data),
  167. .ops = &sandbox_i2c_emul_ops,
  168. };