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authorHeiko Schocher <hs@denx.de>2011-01-13 08:25:00 +0100
committerWolfgang Denk <wd@denx.de>2011-01-18 23:34:26 +0100
commit466f0137e8661fb62cbece1ce764f8369080c6e8 (patch)
tree4662e64737dbf3baa19f0f6f87831393607cffa8 /doc/README.cfi
parent1514579fbfb4237e5ac6dfc5c67742765ea7c95c (diff)
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mpc5200, digsy_mtc: add support for rev5 board version
difference to previous board version: - M29W128GH flash from Numonyx - SDRAM ISSI IS45S16800 (Option A2 105°C) - rev5 uses RTC RV-3029-C2 - update cs0 and cs1 baseaddr and length depending on the detected flash size. - added Werner Pfister <Pfister_Werner@intercontrol.de> as maintainer for the digsy board variants - As the M29W128GH needs a special flash_cmd_reset() document that in the new file doc/README.cfi. - move "#endif /* CONFIG_CMD_IDE */" to the right place - remove LOWBOOT config option for digsy_mtc and digsy_mtc_rev5 boards - change doc/README.cfi as Stefan Roese suggested Signed-off-by: Heiko Schocher <hs@denx.de> Signed-off-by: Stefan Roese <sr@denx.de> Acked-by: Detlev Zundel <dzu@denx.de> cc: Wolfgang Denk <hs@denx.de> cc: Stefan Roese <sr@denx.de> cc: Werner Pfister <Pfister_Werner@intercontrol.de> cc: Detlev Zundel <dzu@denx.de>
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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