Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / u-boot / doc / README.cfi

diff --git a/qemu/roms/u-boot/doc/README.cfi b/qemu/roms/u-boot/doc/README.cfi
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+The common CFI driver provides this weak default implementation for
+flash_cmd_reset():
+
+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);
+       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 seems to have trouble with this reset sequence. In this case
+the board specific code can override this weak default version with a board
+specific function. For example 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);
+}
+
+see also:
+http://www.mail-archive.com/u-boot@lists.denx.de/msg24368.html