KB9202: Add NAND support

Add KB9202 NAND driver

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Signed-off-by: Scott Wood <scottwood@freescale.com>

1 files changed, 150 insertions, 0 deletions

diff --git a/drivers/mtd/nand/kb9202_nand.c b/drivers/mtd/nand/kb9202_nand.c
new file mode 100644
index 0000000..b8f46fa
--- /dev/null
+++ b/drivers/mtd/nand/kb9202_nand.c
@@ -0,0 +1,150 @@
+/*
+ * (C) Copyright 2006
+ * KwikByte <kb9200_dev@kwikbyte.com>
+ *
+ * (C) Copyright 2009
+ * Matthias Kaehlcke <matthias@kaehlcke.net>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/AT91RM9200.h>
+#include <asm/arch/hardware.h>
+
+#include <nand.h>
+
+/*
+ *      hardware specific access to control-lines
+ */
+
+#define MASK_ALE        (1 << 22)       /* our ALE is A22 */
+#define MASK_CLE        (1 << 21)       /* our CLE is A21 */
+
+#define KB9202_NAND_NCE (1 << 28) /* EN* on D28 */
+#define KB9202_NAND_BUSY (1 << 29) /* RB* on D29 */
+
+#define KB9202_SMC2_NWS (1 << 2)
+#define KB9202_SMC2_TDF (1 << 8)
+#define KB9202_SMC2_RWSETUP (1 << 24)
+#define KB9202_SMC2_RWHOLD (1 << 29)
+
+/*
+ *	Board-specific function to access device control signals
+ */
+static void kb9202_nand_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+	struct nand_chip *this = mtd->priv;
+
+	if (ctrl & NAND_CTRL_CHANGE) {
+		ulong IO_ADDR_W = (ulong) this->IO_ADDR_W;
+
+		/* clear ALE and CLE bits */
+		IO_ADDR_W &= ~(MASK_ALE | MASK_CLE);
+
+		if (ctrl & NAND_CLE)
+			IO_ADDR_W |= MASK_CLE;
+
+		if (ctrl & NAND_ALE)
+			IO_ADDR_W |= MASK_ALE;
+
+		this->IO_ADDR_W = (void *) IO_ADDR_W;
+
+		if (ctrl & NAND_NCE)
+			writel(KB9202_NAND_NCE, AT91C_PIOC_CODR);
+		else
+			writel(KB9202_NAND_NCE, AT91C_PIOC_SODR);
+	}
+
+	if (cmd != NAND_CMD_NONE)
+		writeb(cmd, this->IO_ADDR_W);
+}
+
+
+/*
+ * Board-specific function to access the device ready signal.
+ */
+static int kb9202_nand_ready(struct mtd_info *mtd)
+{
+	return readl(AT91C_PIOC_PDSR) & KB9202_NAND_BUSY;
+}
+
+
+/*
+ * Board-specific NAND init.  Copied from include/linux/mtd/nand.h for reference.
+ *
+ * struct nand_chip - NAND Private Flash Chip Data
+ * @IO_ADDR_R:		[BOARDSPECIFIC] address to read the 8 I/O lines of the flash device
+ * @IO_ADDR_W:		[BOARDSPECIFIC] address to write the 8 I/O lines of the flash device
+ * @hwcontrol:		[BOARDSPECIFIC] hardwarespecific function for accesing control-lines
+ * @dev_ready:		[BOARDSPECIFIC] hardwarespecific function for accesing device ready/busy line
+ *			If set to NULL no access to ready/busy is available and the ready/busy information
+ *			is read from the chip status register
+ * @enable_hwecc:	[BOARDSPECIFIC] function to enable (reset) hardware ecc generator. Must only
+ *			be provided if a hardware ECC is available
+ * @eccmode:		[BOARDSPECIFIC] mode of ecc, see defines
+ * @chip_delay:		[BOARDSPECIFIC] chip dependent delay for transfering data from array to read regs (tR)
+ * @options:		[BOARDSPECIFIC] various chip options. They can partly be set to inform nand_scan about
+ *			special functionality. See the defines for further explanation
+*/
+/*
+ * This routine initializes controller and GPIOs.
+ */
+int board_nand_init(struct nand_chip *nand)
+{
+	unsigned int value;
+
+	nand->ecc.mode = NAND_ECC_SOFT;
+	nand->cmd_ctrl = kb9202_nand_hwcontrol;
+	nand->dev_ready = kb9202_nand_ready;
+
+	/* in case running outside of bootloader */
+	writel(1 << AT91C_ID_PIOC, AT91C_PMC_PCER);
+
+	/* setup nand flash access (allow ample margin) */
+	/* 4 wait states, 1 setup, 1 hold, 1 float for 8-bit device */
+	writel(AT91C_SMC2_WSEN | KB9202_SMC2_NWS | KB9202_SMC2_TDF |
+		AT91C_SMC2_DBW_8 | KB9202_SMC2_RWSETUP | KB9202_SMC2_RWHOLD,
+		AT91C_SMC_CSR3);
+
+	/* enable internal NAND controller */
+	value = readl(AT91C_EBI_CSA);
+	value |= AT91C_EBI_CS3A_SMC_SmartMedia;
+	writel(value, AT91C_EBI_CSA);
+
+	/* enable SMOE/SMWE */
+	writel(AT91C_PC1_BFRDY_SMOE | AT91C_PC3_BFBAA_SMWE, AT91C_PIOC_ASR);
+	writel(AT91C_PC1_BFRDY_SMOE | AT91C_PC3_BFBAA_SMWE, AT91C_PIOC_PDR);
+	writel(AT91C_PC1_BFRDY_SMOE | AT91C_PC3_BFBAA_SMWE, AT91C_PIOC_OER);
+
+	/* set NCE to high */
+	writel(KB9202_NAND_NCE, AT91C_PIOC_SODR);
+
+	/* disable output on pin connected to the busy line of the NAND */
+	writel(KB9202_NAND_BUSY, AT91C_PIOC_ODR);
+
+	/* enable the PIO to control NCE and BUSY */
+	writel(KB9202_NAND_NCE | KB9202_NAND_BUSY, AT91C_PIOC_PER);
+
+	/* enable output for NCE */
+	writel(KB9202_NAND_NCE, AT91C_PIOC_OER);
+
+	return (0);
+}