[U-Boot] [PATCH v2 3/7] da850evm: setup the NAND flash timings

Ben Gardiner bengardiner at nanometrics.ca
Thu Oct 14 23:14:30 CEST 2010


The default NAND flash timings are very conservative. This patch assigns the
timings reccomended in the recent linux kernel patch [1] from Sekhar Nori. The
speedup, as reported in that patch, is 5.3x for reads.

[1] http://www.spinics.net/lists/arm-kernel/msg100278.html

Signed-off-by: Ben Gardiner <bengardiner at nanometrics.ca>
CC: Sekhar Nori <nsekhar at ti.com>
To: Sudhakar Rajashekhara <sudhakar.raj at ti.com>

---

V2:
 * Rebased to b69b02b92f59330be9d662110e202cfd3503eafa of u-boot-ti/master

---
 board/davinci/da8xxevm/da850evm.c |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/board/davinci/da8xxevm/da850evm.c b/board/davinci/da8xxevm/da850evm.c
index f84adb9..0eb9e29 100644
--- a/board/davinci/da8xxevm/da850evm.c
+++ b/board/davinci/da8xxevm/da850evm.c
@@ -24,6 +24,7 @@
 #include <common.h>
 #include <i2c.h>
 #include <asm/arch/hardware.h>
+#include <asm/arch/emif_defs.h>
 #include <asm/io.h>
 #include "../common/misc.h"
 #include "common.h"
@@ -98,6 +99,23 @@ int board_init(void)
 	irq_init();
 #endif
 
+
+#ifdef CONFIG_NAND_DAVINCI
+	/*
+	 * NAND CS setup - cycle counts based on da850evm NAND timings in the
+	 * Linux kernel @ 25MHz EMIFA
+	 */
+	writel((DAVINCI_ABCR_WSETUP(0) |
+		DAVINCI_ABCR_WSTROBE(0) |
+		DAVINCI_ABCR_WHOLD(0) |
+		DAVINCI_ABCR_RSETUP(0) |
+		DAVINCI_ABCR_RSTROBE(1) |
+		DAVINCI_ABCR_RHOLD(0) |
+		DAVINCI_ABCR_TA(0) |
+		DAVINCI_ABCR_ASIZE_8BIT),
+	       &davinci_emif_regs->ab2cr); /* CS3 */
+#endif
+
 	/* arch number of the board */
 	gd->bd->bi_arch_number = MACH_TYPE_DAVINCI_DA850_EVM;
 
-- 
1.7.0.4



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