summaryrefslogtreecommitdiff
path: root/drivers/mtd/nand/kb9202_nand.c
diff options
context:
space:
mode:
authorMatthias Kaehlcke <matthias@kaehlcke.net>2009-07-16 21:19:29 +0200
committerScott Wood <scottwood@freescale.com>2009-08-26 15:37:01 -0500
commit403ce1f759b5acec8514cd7e10ce76704fed519c (patch)
tree4b7ca17c417aa451bc2be9a448c594afce52222e /drivers/mtd/nand/kb9202_nand.c
parentd7f4d14a8b317857163ccf3d97e3b1a46ba2282e (diff)
downloadu-boot-imx-403ce1f759b5acec8514cd7e10ce76704fed519c.zip
u-boot-imx-403ce1f759b5acec8514cd7e10ce76704fed519c.tar.gz
u-boot-imx-403ce1f759b5acec8514cd7e10ce76704fed519c.tar.bz2
KB9202: Add NAND support
Add KB9202 NAND driver Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net> Signed-off-by: Scott Wood <scottwood@freescale.com>
Diffstat (limited to 'drivers/mtd/nand/kb9202_nand.c')
-rw-r--r--drivers/mtd/nand/kb9202_nand.c150
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);
+}