nand: Freescale Integrated Flash Controller NAND support

Add NAND support (including spl) on IFC, such as is found on the p1010.

Note that using hardware ECC on IFC with small-page NAND (which is what
comes on the p1010rdb reference board) means there will be insufficient
OOB space for JFFS2, since IFC does not support 1-bit ECC.  UBI should
work, as it does not use OOB for anything but ECC.

When hardware ECC is not enabled in CSOR, software ECC is now used.

Signed-off-by: Dipen Dudhat <Dipen.Dudhat@freescale.com>
[scottwood@freescale.com: ECC rework and misc fixes]
Signed-off-by: Scott Wood <scottwood@freescale.com>

1 files changed, 271 insertions, 0 deletions

diff --git a/nand_spl/nand_boot_fsl_ifc.c b/nand_spl/nand_boot_fsl_ifc.c
new file mode 100644
index 00000000000..44972c5c09a
--- /dev/null
+++ b/nand_spl/nand_boot_fsl_ifc.c
@@ -0,0 +1,271 @@
+/*
+ * NAND boot for FSL Integrated Flash Controller, NAND Flash Control Machine
+ *
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ * Author: Dipen Dudhat <dipen.dudhat@freescale.com>
+ *
+ * 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/fsl_ifc.h>
+#include <linux/mtd/nand.h>
+
+static inline int is_blank(uchar *addr, int page_size)
+{
+	int i;
+
+	for (i = 0; i < page_size; i++) {
+		if (__raw_readb(&addr[i]) != 0xff)
+			return 0;
+	}
+
+	/*
+	 * For the SPL, don't worry about uncorrectable errors
+	 * where the main area is all FFs but shouldn't be.
+	 */
+	return 1;
+}
+
+/* returns nonzero if entire page is blank */
+static inline int check_read_ecc(uchar *buf, u32 *eccstat,
+				 unsigned int bufnum, int page_size)
+{
+	u32 reg = eccstat[bufnum / 4];
+	int errors = (reg >> ((3 - bufnum % 4) * 8)) & 15;
+
+	if (errors == 15) { /* uncorrectable */
+		/* Blank pages fail hw ECC checks */
+		if (is_blank(buf, page_size))
+			return 1;
+
+		puts("ecc error\n");
+		for (;;)
+			;
+	}
+
+	return 0;
+}
+
+static inline void nand_wait(uchar *buf, int bufnum, int page_size)
+{
+	struct fsl_ifc *ifc = IFC_BASE_ADDR;
+	u32 status;
+	u32 eccstat[4];
+	int bufperpage = page_size / 512;
+	int bufnum_end, i;
+
+	bufnum *= bufperpage;
+	bufnum_end = bufnum + bufperpage - 1;
+
+	do {
+		status = in_be32(&ifc->ifc_nand.nand_evter_stat);
+	} while (!(status & IFC_NAND_EVTER_STAT_OPC));
+
+	if (status & IFC_NAND_EVTER_STAT_FTOER) {
+		puts("flash time out error\n");
+		for (;;)
+			;
+	}
+
+	for (i = bufnum / 4; i <= bufnum_end / 4; i++)
+		eccstat[i] = in_be32(&ifc->ifc_nand.nand_eccstat[i]);
+
+	for (i = bufnum; i <= bufnum_end; i++) {
+		if (check_read_ecc(buf, eccstat, i, page_size))
+			break;
+	}
+
+	out_be32(&ifc->ifc_nand.nand_evter_stat, status);
+}
+
+static inline int bad_block(uchar *marker, int port_size)
+{
+	if (port_size == 8)
+		return __raw_readb(marker) != 0xff;
+	else
+		return __raw_readw((u16 *)marker) != 0xffff;
+}
+
+static void nand_load(unsigned int offs, int uboot_size, uchar *dst)
+{
+	struct fsl_ifc *ifc = IFC_BASE_ADDR;
+	uchar *buf = (uchar *)CONFIG_SYS_NAND_BASE;
+	int page_size;
+	int port_size;
+	int pages_per_blk;
+	int blk_size;
+	int bad_marker = 0;
+	int bufnum_mask, bufnum;
+
+	int csor, cspr;
+	int pos = 0;
+	int j = 0;
+
+	int sram_addr;
+	int pg_no;
+
+	/* Get NAND Flash configuration */
+	csor = CONFIG_SYS_NAND_CSOR;
+	cspr = CONFIG_SYS_NAND_CSPR;
+
+	if (!(csor & CSOR_NAND_ECC_DEC_EN)) {
+		/* soft ECC in SPL is unimplemented */
+		puts("WARNING: soft ECC not checked in SPL\n");
+	} else {
+		u32 hwcsor;
+
+		/* make sure board is configured with ECC on boot */
+		hwcsor = in_be32(&ifc->csor_cs[0].csor);
+		if (!(hwcsor & CSOR_NAND_ECC_DEC_EN))
+			puts("WARNING: ECC not checked in SPL, "
+				"check board cfg\n");
+	}
+
+	port_size = (cspr & CSPR_PORT_SIZE_16) ? 16 : 8;
+
+	if (csor & CSOR_NAND_PGS_4K) {
+		page_size = 4096;
+		bufnum_mask = 1;
+	} else if (csor & CSOR_NAND_PGS_2K) {
+		page_size = 2048;
+		bufnum_mask = 3;
+	} else {
+		page_size = 512;
+		bufnum_mask = 15;
+
+		if (port_size == 8)
+			bad_marker = 5;
+	}
+
+	pages_per_blk =
+		32 << ((csor & CSOR_NAND_PB_MASK) >> CSOR_NAND_PB_SHIFT);
+
+	blk_size = pages_per_blk * page_size;
+
+	/* Open Full SRAM mapping for spare are access */
+	out_be32(&ifc->ifc_nand.ncfgr, 0x0);
+
+	/* Clear Boot events */
+	out_be32(&ifc->ifc_nand.nand_evter_stat, 0xffffffff);
+
+	/* Program FIR/FCR for Large/Small page */
+	if (page_size > 512) {
+		out_be32(&ifc->ifc_nand.nand_fir0,
+			 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+			 (IFC_FIR_OP_CA0 << IFC_NAND_FIR0_OP1_SHIFT) |
+			 (IFC_FIR_OP_RA0 << IFC_NAND_FIR0_OP2_SHIFT) |
+			 (IFC_FIR_OP_CMD1 << IFC_NAND_FIR0_OP3_SHIFT) |
+			 (IFC_FIR_OP_BTRD << IFC_NAND_FIR0_OP4_SHIFT));
+		out_be32(&ifc->ifc_nand.nand_fir1, 0x0);
+
+		out_be32(&ifc->ifc_nand.nand_fcr0,
+			(NAND_CMD_READ0 << IFC_NAND_FCR0_CMD0_SHIFT) |
+			(NAND_CMD_READSTART << IFC_NAND_FCR0_CMD1_SHIFT));
+	} else {
+		out_be32(&ifc->ifc_nand.nand_fir0,
+			 (IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
+			 (IFC_FIR_OP_CA0 << IFC_NAND_FIR0_OP1_SHIFT) |
+			 (IFC_FIR_OP_RA0  << IFC_NAND_FIR0_OP2_SHIFT) |
+			 (IFC_FIR_OP_BTRD << IFC_NAND_FIR0_OP3_SHIFT));
+		out_be32(&ifc->ifc_nand.nand_fir1, 0x0);
+
+		out_be32(&ifc->ifc_nand.nand_fcr0,
+			NAND_CMD_READ0 << IFC_NAND_FCR0_CMD0_SHIFT);
+	}
+
+	/* Program FBCR = 0 for full page read */
+	out_be32(&ifc->ifc_nand.nand_fbcr, 0);
+
+	/* Read and copy u-boot on SDRAM from NAND device, In parallel
+	 * check for Bad block if found skip it and read continue to
+	 * next Block
+	 */
+	while (pos < uboot_size) {
+		int i = 0;
+		do {
+			pg_no = offs / page_size;
+			bufnum = pg_no & bufnum_mask;
+			sram_addr = bufnum * page_size * 2;
+
+			out_be32(&ifc->ifc_nand.row0, pg_no);
+			out_be32(&ifc->ifc_nand.col0, 0);
+			/* start read */
+			out_be32(&ifc->ifc_nand.nandseq_strt,
+				IFC_NAND_SEQ_STRT_FIR_STRT);
+
+			/* wait for read to complete */
+			nand_wait(&buf[sram_addr], bufnum, page_size);
+
+			/*
+			 * If either of the first two pages are marked bad,
+			 * continue to the next block.
+			 */
+			if (i++ < 2 &&
+			    bad_block(&buf[sram_addr + page_size + bad_marker],
+				      port_size)) {
+				puts("skipping\n");
+				offs = (offs + blk_size) & ~(blk_size - 1);
+				pos &= ~(blk_size - 1);
+				break;
+			}
+
+			for (j = 0; j < page_size; j++)
+				dst[pos + j] = __raw_readb(&buf[sram_addr + j]);
+
+			pos += page_size;
+			offs += page_size;
+		} while ((offs & (blk_size - 1)) && (pos < uboot_size));
+	}
+}
+
+/*
+ * Main entrypoint for NAND Boot. It's necessary that SDRAM is already
+ * configured and available since this code loads the main U-boot image
+ * from NAND into SDRAM and starts from there.
+ */
+void nand_boot(void)
+{
+	__attribute__((noreturn)) void (*uboot)(void);
+
+	/*
+	 * Load U-Boot image from NAND into RAM
+	 */
+	nand_load(CONFIG_SYS_NAND_U_BOOT_OFFS, CONFIG_SYS_NAND_U_BOOT_SIZE,
+		  (uchar *)CONFIG_SYS_NAND_U_BOOT_DST);
+
+#ifdef CONFIG_NAND_ENV_DST
+	nand_load(CONFIG_ENV_OFFSET, CONFIG_ENV_SIZE,
+		  (uchar *)CONFIG_NAND_ENV_DST);
+
+#ifdef CONFIG_ENV_OFFSET_REDUND
+	nand_load(CONFIG_ENV_OFFSET_REDUND, CONFIG_ENV_SIZE,
+		  (uchar *)CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE);
+#endif
+#endif
+
+	/*
+	 * Jump to U-Boot image
+	 */
+	/*
+	 * Clean d-cache and invalidate i-cache, to
+	 * make sure that no stale data is executed.
+	 */
+	flush_cache(CONFIG_SYS_NAND_U_BOOT_DST, CONFIG_SYS_NAND_U_BOOT_SIZE);
+	uboot = (void *)CONFIG_SYS_NAND_U_BOOT_START;
+	uboot();
+}