From: Benoît Thébaudeau Date: Wed, 8 Aug 2012 03:55:32 +0000 (+0000) Subject: KARO TX25: Fix NAND Flash R/W cycle times X-Git-Tag: v2012.10-rc3~10^2~68^2~4 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5527024fdb10798d2975197f287457b29e2d4084;p=kernel%2Fu-boot.git KARO TX25: Fix NAND Flash R/W cycle times The NAND Flash of the KARO TX25 board is a Samsung K9F1G08U0B with 25-ns R/W cycle times. However, the NFC clock for this board was set to 66.5 MHz, so using the NFC driver in symmetric mode (i.e. 1 NFC clock cycle = 1 NF R/W cycle) resulted in NF R/W cycle times of 15 ns, hence corrupted NF accesses. This patch fixes this issue by setting the NFC clock to the highest frequency complying to the 25-ns NF R/W cycle times specification, i.e. 33.25 MHz. Signed-off-by: Benoît Thébaudeau Cc: John Rigby Cc: Scott Wood Cc: Stefano Babic Cc: Daniel Gachet Acked-by: Stefano Babic --- diff --git a/board/karo/tx25/lowlevel_init.S b/board/karo/tx25/lowlevel_init.S index 823df10..eb3f187 100644 --- a/board/karo/tx25/lowlevel_init.S +++ b/board/karo/tx25/lowlevel_init.S @@ -67,6 +67,14 @@ write32 0x53f80008, 0x20034000 /* + * PCDR2: NFC = 33.25 MHz + * This is required for the NAND Flash of this board, which is a Samsung + * K9F1G08U0B with 25-ns R/W cycle times, in order to make it work with + * the NFC driver in symmetric (i.e. one-cycle) mode. + */ + write32 0x53f80020, 0x01010103 + + /* * enable all implemented clocks in all three * clock control registers */