davinci: add support for aemif timing configuration

This patch adds support to configure the AEMIF interface
with supplied timing values.

Since this capability is useful both from NOR and NAND
flashes, it is provided as a new interface and in a file
of its own.

AEMIF timing configuration is required in cases:

1) Where the AEMIF clock rate can change at runtime (a side
   affect of cpu frequency change).

2) Where U-Boot does not support NAND/NOR but supports other
   media like SPI Flash or MMC/SD and thus does not care about
   setting up the AEMIF timing for kernel to use.

3) Where U-Boot just hasn't configured the timing values and
   cannot be upgraded because the box is already in the field.

Since there is now a header file for AEMIF interface, the
common (non-NAND specific) defines for AEMIF registers have
been moved from nand.h into the newly created aemif.h

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/arch/arm/mach-davinci/include/mach/aemif.h b/arch/arm/mach-davinci/include/mach/aemif.h
new file mode 100644
index 000000000000..05b293443097
--- /dev/null
+++ b/arch/arm/mach-davinci/include/mach/aemif.h
@@ -0,0 +1,36 @@
+/*
+ * TI DaVinci AEMIF support
+ *
+ * Copyright 2010 (C) Texas Instruments, Inc. http://www.ti.com/
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+#ifndef _MACH_DAVINCI_AEMIF_H
+#define _MACH_DAVINCI_AEMIF_H
+
+#define NRCSR_OFFSET		0x00
+#define AWCCR_OFFSET		0x04
+#define A1CR_OFFSET		0x10
+
+#define ACR_ASIZE_MASK		0x3
+#define ACR_EW_MASK		BIT(30)
+#define ACR_SS_MASK		BIT(31)
+
+/* All timings in nanoseconds */
+struct davinci_aemif_timing {
+	u8	wsetup;
+	u8	wstrobe;
+	u8	whold;
+
+	u8	rsetup;
+	u8	rstrobe;
+	u8	rhold;
+
+	u8	ta;
+};
+
+int davinci_aemif_setup_timing(struct davinci_aemif_timing *t,
+					void __iomem *base, unsigned cs);
+#endif