[U-Boot] [PATCH 08/13 v3] ARM: OMAP3: Add NAND support
dirk.behme at googlemail.com
dirk.behme at googlemail.com
Thu Oct 9 20:00:18 CEST 2008
Subject: [PATCH 08/13 v3] ARM: OMAP3: Add NAND support
From: Dirk Behme <dirk.behme at gmail.com>
Add NAND support
Signed-off-by: Dirk Behme <dirk.behme at gmail.com>
---
Changes in version v3:
- Fix/update NAND driver and seperate it into an own patch as proposed by Scott Wood
drivers/mtd/nand/Makefile | 1
drivers/mtd/nand/omap3.c | 380 ++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 381 insertions(+)
Index: u-boot-arm/drivers/mtd/nand/Makefile
===================================================================
--- u-boot-arm.orig/drivers/mtd/nand/Makefile
+++ u-boot-arm/drivers/mtd/nand/Makefile
@@ -38,6 +38,7 @@ endif
COBJS-$(CONFIG_NAND_FSL_ELBC) += fsl_elbc_nand.o
COBJS-$(CONFIG_NAND_FSL_UPM) += fsl_upm.o
COBJS-$(CONFIG_NAND_S3C64XX) += s3c64xx.o
+COBJS-$(CONFIG_NAND_OMAP3) += omap3.o
endif
COBJS := $(COBJS-y)
Index: u-boot-arm/drivers/mtd/nand/omap3.c
===================================================================
--- /dev/null
+++ u-boot-arm/drivers/mtd/nand/omap3.c
@@ -0,0 +1,380 @@
+/*
+ * (C) Copyright 2004-2008 Texas Instruments, <www.ti.com>
+ * Rohit Choraria <rohitkc at ti.com>
+ *
+ * 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/mem.h>
+#include <linux/mtd/nand_ecc.h>
+#include <nand.h>
+
+unsigned char cs;
+volatile unsigned long gpmc_cs_base_add;
+
+#define GPMC_BUF_EMPTY 0
+#define GPMC_BUF_FULL 1
+
+/*
+ * omap_nand_hwcontrol - Set the address pointers corretly for the
+ * following address/data/command operation
+ */
+static void omap_nand_hwcontrol(struct mtd_info *mtd, int cmd,
+ unsigned int ctrl)
+{
+ register struct nand_chip *this = mtd->priv;
+
+ /* Point the IO_ADDR to DATA and ADDRESS registers instead
+ of chip address */
+ switch (ctrl) {
+ case NAND_CTRL_CHANGE | NAND_CTRL_CLE:
+ this->IO_ADDR_W = (void *) gpmc_cs_base_add + GPMC_NAND_CMD;
+ this->IO_ADDR_R = (void *) gpmc_cs_base_add + GPMC_NAND_DAT;
+ break;
+ case NAND_CTRL_CHANGE | NAND_CTRL_ALE:
+ this->IO_ADDR_W = (void *) gpmc_cs_base_add + GPMC_NAND_ADR;
+ this->IO_ADDR_R = (void *) gpmc_cs_base_add + GPMC_NAND_DAT;
+ break;
+ case NAND_CTRL_CHANGE | NAND_NCE:
+ this->IO_ADDR_W = (void *) gpmc_cs_base_add + GPMC_NAND_DAT;
+ this->IO_ADDR_R = (void *) gpmc_cs_base_add + GPMC_NAND_DAT;
+ break;
+ }
+
+ if (cmd != NAND_CMD_NONE)
+ writeb(cmd, this->IO_ADDR_W);
+}
+
+/*
+ * omap_nand_wait - called primarily after a program/erase operation
+ * so that we access NAND again only after the device
+ * is ready again.
+ * @mtd: MTD device structure
+ * @chip: nand_chip structure
+ */
+static int omap_nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
+{
+ register struct nand_chip *this = mtd->priv;
+ int status = 0;
+
+ this->IO_ADDR_W = (void *) gpmc_cs_base_add + GPMC_NAND_CMD;
+ this->IO_ADDR_R = (void *) gpmc_cs_base_add + GPMC_NAND_DAT;
+ /* Send the status command and loop until the device is free */
+ while (!(status & 0x40)) {
+ writeb(NAND_CMD_STATUS & 0xFF, this->IO_ADDR_W);
+ status = readb(this->IO_ADDR_R);
+ }
+ return status;
+}
+
+/*
+ * omap_nand_write_buf16 - [DEFAULT] write buffer to chip
+ * @mtd: MTD device structure
+ * @buf: data buffer
+ * @len: number of bytes to write
+ *
+ * Default write function for 16bit buswith
+ */
+static void omap_nand_write_buf16(struct mtd_info *mtd, const u_char *buf,
+ int len)
+{
+ int i;
+ struct nand_chip *this = mtd->priv;
+ u16 *p = (u16 *) buf;
+ len >>= 1;
+
+ for (i = 0; i < len; i++) {
+ writew(p[i], this->IO_ADDR_W);
+ while (GPMC_BUF_EMPTY == (readl(GPMC_STATUS) & GPMC_BUF_FULL));
+ }
+}
+
+/*
+ * omap_hwecc_init - Initialize the Hardware ECC for NAND flash in
+ * GPMC controller
+ * @mtd: MTD device structure
+ *
+ */
+static void omap_hwecc_init(struct nand_chip *chip)
+{
+ unsigned long val = 0x0;
+
+ /* Init ECC Control Register */
+ /* Clear all ECC | Enable Reg1 */
+ val = ((0x00000001 << 8) | 0x00000001);
+ writel(val, GPMC_BASE + GPMC_ECC_CONTROL);
+ writel(0x3fcff000, GPMC_BASE + GPMC_ECC_SIZE_CONFIG);
+}
+
+/*
+ * gen_true_ecc - This function will generate true ECC value, which
+ * can be used when correcting data read from NAND flash memory core
+ *
+ * @ecc_buf: buffer to store ecc code
+ *
+ * @return: re-formatted ECC value
+ */
+static unsigned int gen_true_ecc(u8 *ecc_buf)
+{
+ return ecc_buf[0] | (ecc_buf[1] << 16) | ((ecc_buf[2] & 0xF0) << 20) |
+ ((ecc_buf[2] & 0x0F) << 8);
+}
+
+/*
+ * omap_correct_data - Compares the ecc read from nand spare area with ECC
+ * registers values and corrects one bit error if it has occured
+ * Further details can be had from OMAP TRM and the following selected links:
+ * http://en.wikipedia.org/wiki/Hamming_code
+ * http://www.cs.utexas.edu/users/plaxton/c/337/05f/slides/ErrorCorrection-4.pdf
+ *
+ * @mtd: MTD device structure
+ * @dat: page data
+ * @read_ecc: ecc read from nand flash
+ * @calc_ecc: ecc read from ECC registers
+ *
+ * @return 0 if data is OK or corrected, else returns -1
+ */
+static int omap_correct_data(struct mtd_info *mtd, u_char *dat,
+ u_char *read_ecc, u_char *calc_ecc)
+{
+ unsigned int orig_ecc, new_ecc, res, hm;
+ unsigned short parity_bits, byte;
+ unsigned char bit;
+
+ /* Regenerate the orginal ECC */
+ orig_ecc = gen_true_ecc(read_ecc);
+ new_ecc = gen_true_ecc(calc_ecc);
+ /* Get the XOR of real ecc */
+ res = orig_ecc ^ new_ecc;
+ if (res) {
+ /* Get the hamming width */
+ hm = hweight32(res);
+ /* Single bit errors can be corrected! */
+ if (hm == 12) {
+ /* Correctable data! */
+ parity_bits = res >> 16;
+ bit = (parity_bits & 0x7);
+ byte = (parity_bits >> 3) & 0x1FF;
+ /* Flip the bit to correct */
+ dat[byte] ^= (0x1 << bit);
+ } else if (hm == 1) {
+ printf("Error: Ecc is wrong\n");
+ /* ECC itself is corrupted */
+ return 2;
+ } else {
+ printf("Error: Bad compare! failed\n");
+ /* detected 2 bit error */
+ return -1;
+ }
+ }
+ return 0;
+}
+
+/*
+ * omap_calculate_ecc - Generate non-inverted ECC bytes.
+ *
+ * Using noninverted ECC can be considered ugly since writing a blank
+ * page ie. padding will clear the ECC bytes. This is no problem as
+ * long nobody is trying to write data on the seemingly unused page.
+ * Reading an erased page will produce an ECC mismatch between
+ * generated and read ECC bytes that has to be dealt with separately.
+ * E.g. if page is 0xFF (fresh erased), and if HW ECC engine within GPMC
+ * is used, the result of read will be 0x0 while the ECC offsets of the
+ * spare area will be 0xFF which will result in an ECC mismatch.
+ * @mtd: MTD structure
+ * @dat: unused
+ * @ecc_code: ecc_code buffer
+ */
+static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
+ u_char *ecc_code)
+{
+ unsigned long val = 0x0;
+ unsigned long reg;
+
+ /* Start Reading from HW ECC1_Result = 0x200 */
+ reg = (unsigned long) (GPMC_BASE + GPMC_ECC1_RESULT);
+ val = readl(reg);
+
+ ecc_code[0] = val & 0xFF;
+ ecc_code[1] = (val >> 16) & 0xFF;
+ ecc_code[2] = ((val >> 8) & 0x0F) | ((val >> 20) & 0xF0);
+
+ /* Stop reading anymore ECC vals and clear old results
+ * enable will be called if more reads are required */
+ reg = (unsigned long) (GPMC_BASE + GPMC_ECC_CONFIG);
+ writel(0x000, reg);
+
+ return 0;
+}
+
+/*
+ * omap_enable_ecc - This function enables the hardware ecc functionality
+ * @mtd: MTD device structure
+ * @mode: Read/Write mode
+ */
+static void omap_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+ struct nand_chip *chip = mtd->priv;
+ unsigned int val, dev_width = (chip->options & NAND_BUSWIDTH_16) >> 1;
+
+ switch (mode) {
+ case NAND_ECC_READ:
+ case NAND_ECC_WRITE:
+ /* Clear the ecc result registers
+ * select ecc reg as 1
+ */
+ writel(0x101, GPMC_BASE + GPMC_ECC_CONTROL);
+ /* Size 0 = 0xFF, Size1 is 0xFF - both are 512 bytes
+ * tell all regs to generate size0 sized regs
+ * we just have a single ECC engine for all CS
+ */
+ writel(0x3FCFF000, GPMC_BASE + GPMC_ECC_SIZE_CONFIG);
+ val = (dev_width << 7) | (cs << 1) | (0x1);
+ writel(val, GPMC_BASE + GPMC_ECC_CONFIG);
+ break;
+ default:
+ printf("Error: Unrecognized Mode[%d]!\n", mode);
+ break;
+ }
+}
+
+static struct nand_ecclayout hw_nand_oob_64 = {
+ .eccbytes = 12,
+ .eccpos = {
+ 2, 3, 4, 5,
+ 6, 7, 8, 9,
+ 10, 11, 12, 13},
+ .oobfree = { {14, 50} }
+};
+
+static struct nand_ecclayout sw_nand_oob_64 = {
+ .eccbytes = 24,
+ .eccpos = {
+ 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55,
+ 56, 57, 58, 59, 60, 61, 62, 63},
+ .oobfree = { {2, 38} }
+};
+
+void omap_nand_switch_ecc(int hardware)
+{
+ struct nand_chip *nand;
+
+ if (nand_curr_device < 0 ||
+ nand_curr_device >= CONFIG_SYS_MAX_NAND_DEVICE ||
+ !nand_info[nand_curr_device].name) {
+ printf("Error: Can't switch ecc, no devices available\n");
+ return;
+ }
+
+ nand = (&nand_info[nand_curr_device])->priv;
+
+ if (!hardware) {
+ nand->ecc.mode = NAND_ECC_SOFT;
+ nand->ecc.layout = &sw_nand_oob_64;
+ nand->ecc.size = 256; /* set default eccsize */
+ nand->ecc.bytes = 3;
+ nand->ecc.steps = 8;
+ nand->ecc.hwctl = 0;
+ nand->ecc.calculate = nand_calculate_ecc;
+ nand->ecc.correct = nand_correct_data;
+ } else {
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.layout = &hw_nand_oob_64;
+ nand->ecc.size = 512;
+ nand->ecc.bytes = 3;
+ nand->ecc.steps = 4;
+ nand->ecc.hwctl = omap_enable_hwecc;
+ nand->ecc.correct = omap_correct_data;
+ nand->ecc.calculate = omap_calculate_ecc;
+ omap_hwecc_init(nand);
+ }
+}
+
+/*
+ * Board-specific NAND initialization. The following members of the
+ * argument are board-specific:
+ * - IO_ADDR_R: address to read the 8 I/O lines of the flash device
+ * - IO_ADDR_W: address to write the 8 I/O lines of the flash device
+ * - cmd_ctrl: hardwarespecific function for accesing control-lines
+ * - waitfunc: hardwarespecific function for accesing device ready/busy line
+ * - ecc.hwctl: function to enable (reset) hardware ecc generator
+ * - ecc.mode: mode of ecc, see defines
+ * - chip_delay: chip dependent delay for transfering data from array to
+ * read regs (tR)
+ * - options: various chip options. They can partly be set to inform
+ * nand_scan about special functionality. See the defines for further
+ * explanation
+ */
+int board_nand_init(struct nand_chip *nand)
+{
+ int gpmc_config = 0;
+ cs = 0;
+ while (cs <= GPMC_MAX_CS) {
+ /* Each GPMC set for a single CS is at offset 0x30 */
+ /* already remapped for us */
+ gpmc_cs_base_add = (GPMC_CONFIG_CS0 + (cs * 0x30));
+ /* xloader/Uboot would have written the NAND type for us
+ * NOTE: This is a temporary measure and cannot handle ONENAND.
+ * The proper way of doing this is to pass the setup of
+ * u-boot up to kernel using kernel params - something on
+ * the lines of machineID
+ */
+ /* Check if NAND type is set */
+ if ((readl(gpmc_cs_base_add + GPMC_CONFIG1) & 0xC00) ==
+ 0x800) {
+ /* Found it!! */
+ break;
+ }
+ cs++;
+ }
+ if (cs > GPMC_MAX_CS) {
+ printf("NAND: Unable to find NAND settings in " \
+ "GPMC Configuration - quitting\n");
+ }
+
+ gpmc_config = readl(GPMC_CONFIG);
+ /* Disable Write protect */
+ gpmc_config |= 0x10;
+ writel(gpmc_config, GPMC_CONFIG);
+
+ nand->IO_ADDR_R = (int *) gpmc_cs_base_add + GPMC_NAND_DAT;
+ nand->IO_ADDR_W = (int *) gpmc_cs_base_add + GPMC_NAND_CMD;
+
+ nand->cmd_ctrl = omap_nand_hwcontrol;
+ nand->options = NAND_NO_PADDING | NAND_CACHEPRG | NAND_NO_AUTOINCR |
+ NAND_BUSWIDTH_16 | NAND_NO_AUTOINCR;
+
+ /* Use custom write buf due to additional delay. Read uses default. */
+ nand->write_buf = omap_nand_write_buf16;
+ nand->ecc.mode = NAND_ECC_SOFT;
+ /* if RDY/BSY line is connected to OMAP then use the omap ready
+ * function and the generic nand_wait function which reads the
+ * status register after monitoring the RDY/BSY line. Otherwise
+ * use a standard chip delay which is slightly more than tR
+ * (AC Timing) of the NAND device and read the status register
+ * until you get a failure or success
+ */
+ nand->waitfunc = omap_nand_wait;
+ nand->chip_delay = 50;
+
+ return 0;
+}
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