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+The common CFI driver provides this weak default implementation for
+flash_cmd_reset():
+
+static void __flash_cmd_reset(flash_info_t *info)
+{
+ /*
+ * We do not yet know what kind of commandset to use, so we issue
+ * the reset command in both Intel and AMD variants, in the hope
+ * that AMD flash roms ignore the Intel command.
+ */
+ flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
+ udelay(1);
+ flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
+}
+void flash_cmd_reset(flash_info_t *info)
+ __attribute__((weak,alias("__flash_cmd_reset")));
+
+Some flash chips seem to have trouble with this reset sequence.
+In this case, board-specific code can override this weak default
+version with a board-specific function.
+
+At the time of writing, there are two boards that define their own
+routine for this.
+
+First, the digsy_mtc board equipped with the M29W128GH from Numonyx
+needs this version to function properly:
+
+void flash_cmd_reset(flash_info_t *info)
+{
+ flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
+}
+
+In addition, the t3corp board defines the routine thusly:
+
+void flash_cmd_reset(flash_info_t *info)
+{
+ /*
+ * FLASH at address CONFIG_SYS_FLASH_BASE is a Spansion chip and
+ * needs the Spansion type reset commands. The other flash chip
+ * is located behind a FPGA (Xilinx DS617) and needs the Intel type
+ * reset command.
+ */
+ if (info->start[0] == CONFIG_SYS_FLASH_BASE)
+ flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
+ else
+ flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
+}
+
+see also:
+http://www.mail-archive.com/u-boot@lists.denx.de/msg24368.html
+
+
+Config Option
+
+ CONFIG_SYS_MAX_FLASH_SECT: Number of sectors available on Flash device
+
+ CONFIG_SYS_FLASH_CFI_WIDTH: Data-width of the flash device
+
+ CONFIG_CMD_FLASH: Enables Flash command library
+
+ CONFIG_FLASH_CFI_DRIVER: Enables CFI Flash driver
+
+ CONFIG_FLASH_CFI_MTD: Enables MTD frame work for NOR Flash devices