[U-Boot] [PATCH v3 1/2] i.MX6: nand: add nandbcb update command
Jagan Teki
jagannadh.teki at gmail.com
Wed Feb 7 16:03:21 UTC 2018
Writing/updating boot image in nand device is not
straight forward in i.MX6 platform and it requires
boot control block(BCB) to be configured.
It becomes difficult to use uboot 'nand' command to
write BCB since it requires platform specific attributes
need to be taken care of.
It is even difficult to use existing msx-nand.c driver by
incorporating BCB attributes like mxs_dma_desc does
because it requires change in mtd and nand command.
So, cmd_nandbcb implemented in arch/arm/mach-imx
BCB contains two data structures, Firmware Configuration Block(FCB)
and Discovered Bad Block Table(DBBT). FCB has nand timings,
DBBT search area, page address of primary and secondary firmware.
On summary, nandbcb update will
- erase the entire partition
- create BCB by creating 4 FCB/BDDT block followed by
2 FW blocks based on partition size and erasesize.
- fill FCB/DBBT structures
- write FW/SPL in FW0 and FW1(same image in two times)
- write FCB/DBBT in first 4 blocks
for nand boot, up on reset bootrom look for FCB structure in
first block's if FCB found the nand timings are loaded for
further reads. once FCB read done, DTTB will load and
finally primary or secondary firmware will load which is boot image.
See Section 4 from doc/README.imx6 for more usage information.
Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
Signed-off-by: Sergey Kubushyn <ksi at koi8.net>
---
Changes for v3:
- Fixed multi-line comments
- Better error handling for failed allocations
Changes for v2:
- Fixed commit message notes
- Updated proper commit message
- Update doc/README.imx6 with NAND boot details
- Fixed long length variable names.
- Fixed Gigantic variable name.
- NULL checks for kzalloc
- Move Kconfig option in separate patch
- Fixed checkpatch warninigs
arch/arm/include/asm/mach-imx/imx-nandbcb.h | 111 ++++++++
arch/arm/include/asm/mach-imx/mxs-nand.h | 15 ++
arch/arm/mach-imx/Makefile | 1 +
arch/arm/mach-imx/cmd_nandbcb.c | 379 ++++++++++++++++++++++++++++
doc/README.imx6 | 77 ++++++
drivers/mtd/nand/mxs_nand.c | 8 +-
6 files changed, 587 insertions(+), 4 deletions(-)
create mode 100644 arch/arm/include/asm/mach-imx/imx-nandbcb.h
create mode 100644 arch/arm/include/asm/mach-imx/mxs-nand.h
create mode 100644 arch/arm/mach-imx/cmd_nandbcb.c
diff --git a/arch/arm/include/asm/mach-imx/imx-nandbcb.h b/arch/arm/include/asm/mach-imx/imx-nandbcb.h
new file mode 100644
index 0000000..759b588
--- /dev/null
+++ b/arch/arm/include/asm/mach-imx/imx-nandbcb.h
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2017 Jagan Teki <jagan at amarulasolutions.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef _IMX_NAND_BCB_H_
+#define _IMX_NAND_BCB_H_
+
+#define FCB_FINGERPRINT 0x20424346 /* 'FCB' */
+#define FCB_VERSION_1 0x01000000
+
+#define DBBT_FINGERPRINT2 0x54424244 /* 'DBBT' */
+#define DBBT_VERSION_1 0x01000000
+
+struct dbbt_block {
+ u32 checksum; /* reserved on i.MX6 */
+ u32 fingerprint;
+ u32 version;
+ u32 numberbb; /* reserved on i.MX6 */
+ u32 dbbtnumofpages;
+};
+
+struct fcb_block {
+ u32 checksum; /* First fingerprint in first byte */
+ u32 fingerprint; /* 2nd fingerprint at byte 4 */
+ u32 version; /* 3rd fingerprint at byte 8 */
+ u8 datasetup;
+ u8 datahold;
+ u8 addresssetup;
+ u8 dsample_time;
+
+ /* These are for application use only and not for ROM. */
+ u8 nandtiming;
+ u8 rea;
+ u8 rloh;
+ u8 rhoh;
+ u32 pagesize; /* 2048 for 2K pages, 4096 for 4K pages */
+ u32 oob_pagesize; /* 2112 for 2K pages, 4314 for 4K pages */
+ u32 sectors; /* Number of 2K sections per block */
+ u32 nr_nand; /* Total Number of NANDs - not used by ROM */
+ u32 nr_die; /* Number of separate chips in this NAND */
+ u32 celltype; /* MLC or SLC */
+ u32 ecc_type; /* Type of ECC, can be one of BCH-0-20 */
+ u32 ecc_nr; /* Number of bytes for Block0 - BCH */
+
+ /* Block size in bytes for all blocks other than Block0 - BCH */
+ u32 ecc_size;
+ u32 ecc_level; /* Ecc level for Block 0 - BCH */
+ u32 meta_size; /* Metadata size - BCH */
+ /* Number of blocks per page for ROM use - BCH */
+ u32 nr_blocks;
+ u32 ecc_type_sdk; /* Type of ECC, can be one of BCH-0-20 */
+ u32 ecc_nr_sdk; /* Number of bytes for Block0 - BCH */
+ /* Block size in bytes for all blocks other than Block0 - BCH */
+ u32 ecc_size_sdk;
+ u32 ecc_level_sdk; /* Ecc level for Block 0 - BCH */
+ /* Number of blocks per page for SDK use - BCH */
+ u32 nr_blocks_sdk;
+ u32 meta_size_sdk; /* Metadata size - BCH */
+ u32 erase_th; /* To set into BCH_MODE register */
+
+ /*
+ * 0: normal boot
+ * 1: to load patch starting next to FCB
+ */
+ u32 bootpatch;
+ u32 patch_size; /* Size of patch in sectors */
+ u32 fw1_start; /* Firmware image starts on this sector */
+ u32 fw2_start; /* Secondary FW Image starting Sector */
+ u32 fw1_pages; /* Number of sectors in firmware image */
+ u32 fw2_pages; /* Number of sector in secondary FW image */
+ u32 dbbt_start; /* Page address where dbbt search area begins */
+
+ /*
+ * Byte in page data that have manufacturer marked bad block marker,
+ * this will be swapped with metadata[0] to complete page data.
+ */
+ u32 bb_byte;
+
+ /*
+ * For BCH ECC sizes other than 8 and 16 the bad block marker does not
+ * start at 0th bit of bb_byte. This field is used to get to
+ * the start bit of bad block marker byte with in bb_byte
+ */
+ u32 bb_start_bit;
+
+ /*
+ * FCB value that gives byte offset for
+ * bad block marker on physical NAND page
+ */
+ u32 phy_offset;
+ u32 bchtype;
+
+ u32 readlatency;
+ u32 preambledelay;
+ u32 cedelay;
+ u32 postambledelay;
+ u32 cmdaddpause;
+ u32 datapause;
+ u32 tmspeed;
+ u32 busytimeout;
+
+ /* the flag to enable (1)/disable(0) bi swap */
+ u32 disbbm;
+
+ /* The swap position of main area in spare area */
+ u32 spare_offset;
+};
+
+#endif /* _IMX_NAND_BCB_H_ */
diff --git a/arch/arm/include/asm/mach-imx/mxs-nand.h b/arch/arm/include/asm/mach-imx/mxs-nand.h
new file mode 100644
index 0000000..38f5d90
--- /dev/null
+++ b/arch/arm/include/asm/mach-imx/mxs-nand.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (C) 2017 Jagan Teki <jagan at amarulasolutions.com>
+ * Copyright (C) 2016 Sergey Kubushyn <ksi at koi8.net>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef _MXS_NAND_
+#define _MXS_NAND_
+
+uint32_t mxs_nand_get_ecc_strength(u32 page_data_size, uint32_t page_oob_size);
+uint32_t mxs_nand_mark_byte_offset(struct mtd_info *mtd);
+uint32_t mxs_nand_mark_bit_offset(struct mtd_info *mtd);
+
+#endif /* _MXS_NAND_ */
diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 95a542f..29eedb1 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -56,6 +56,7 @@ ifneq ($(CONFIG_SPL_BUILD),y)
obj-$(CONFIG_CMD_BMODE) += cmd_bmode.o
obj-$(CONFIG_CMD_HDMIDETECT) += cmd_hdmidet.o
obj-$(CONFIG_CMD_DEKBLOB) += cmd_dek.o
+obj-$(CONFIG_CMD_NANDBCB) += cmd_nandbcb.o
endif
PLUGIN = board/$(BOARDDIR)/plugin
diff --git a/arch/arm/mach-imx/cmd_nandbcb.c b/arch/arm/mach-imx/cmd_nandbcb.c
new file mode 100644
index 0000000..93e5150
--- /dev/null
+++ b/arch/arm/mach-imx/cmd_nandbcb.c
@@ -0,0 +1,379 @@
+/*
+ * i.MX6 nand boot control block(bcb).
+ *
+ * Based on the common/imx-bbu-nand-fcb.c from barebox and imx kobs-ng
+ *
+ * Copyright (C) 2017 Jagan Teki <jagan at amarulasolutions.com>
+ * Copyright (C) 2016 Sergey Kubushyn <ksi at koi8.net>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <nand.h>
+
+#include <asm/io.h>
+#include <jffs2/jffs2.h>
+#include <linux/mtd/mtd.h>
+
+#include <asm/mach-imx/mxs-nand.h>
+#include <asm/mach-imx/imx-nandbcb.h>
+#include <asm/mach-imx/imximage.cfg>
+
+#define BF_VAL(v, bf) (((v) & bf##_MASK) >> bf##_OFFSET)
+#define GETBIT(v, n) (((v) >> (n)) & 0x1)
+
+static u8 calculate_parity_13_8(u8 d)
+{
+ u8 p = 0;
+
+ p |= (GETBIT(d, 6) ^ GETBIT(d, 5) ^ GETBIT(d, 3) ^ GETBIT(d, 2)) << 0;
+ p |= (GETBIT(d, 7) ^ GETBIT(d, 5) ^ GETBIT(d, 4) ^ GETBIT(d, 2) ^
+ GETBIT(d, 1)) << 1;
+ p |= (GETBIT(d, 7) ^ GETBIT(d, 6) ^ GETBIT(d, 5) ^ GETBIT(d, 1) ^
+ GETBIT(d, 0)) << 2;
+ p |= (GETBIT(d, 7) ^ GETBIT(d, 4) ^ GETBIT(d, 3) ^ GETBIT(d, 0)) << 3;
+ p |= (GETBIT(d, 6) ^ GETBIT(d, 4) ^ GETBIT(d, 3) ^ GETBIT(d, 2) ^
+ GETBIT(d, 1) ^ GETBIT(d, 0)) << 4;
+
+ return p;
+}
+
+static void encode_hamming_13_8(void *_src, void *_ecc, size_t size)
+{
+ int i;
+ u8 *src = _src;
+ u8 *ecc = _ecc;
+
+ for (i = 0; i < size; i++)
+ ecc[i] = calculate_parity_13_8(src[i]);
+}
+
+static u32 calc_chksum(void *buf, size_t size)
+{
+ u32 chksum = 0;
+ u8 *bp = buf;
+ size_t i;
+
+ for (i = 0; i < size; i++)
+ chksum += bp[i];
+
+ return ~chksum;
+}
+
+static void fill_fcb(struct fcb_block *fcb, struct mtd_info *mtd)
+{
+ fcb->fingerprint = FCB_FINGERPRINT;
+ fcb->version = FCB_VERSION_1;
+ fcb->pagesize = mtd->writesize;
+ fcb->oob_pagesize = mtd->writesize + mtd->oobsize;
+ fcb->sectors = mtd->erasesize / mtd->writesize;
+
+ /* Divide ECC strength by two and save the value into FCB structure. */
+ fcb->ecc_level =
+ mxs_nand_get_ecc_strength(mtd->writesize, mtd->oobsize) >> 1;
+
+ fcb->ecc_type = fcb->ecc_level;
+
+ /* Also hardcoded in kobs-ng */
+ fcb->ecc_nr = 0x00000200;
+ fcb->ecc_size = 0x00000200;
+ fcb->datasetup = 80;
+ fcb->datahold = 60;
+ fcb->addresssetup = 25;
+ fcb->dsample_time = 6;
+ fcb->meta_size = 10;
+
+ /* DBBT search area starts at second page on first block */
+ fcb->dbbt_start = 1;
+
+ fcb->bb_byte = mxs_nand_mark_byte_offset(mtd);
+ fcb->bb_start_bit = mxs_nand_mark_bit_offset(mtd);
+
+ fcb->phy_offset = mtd->writesize;
+
+ fcb->nr_blocks = mtd->writesize / fcb->ecc_nr - 1;
+
+ fcb->checksum = calc_chksum((void *)fcb + 4, sizeof(*fcb) - 4);
+}
+
+static int dbbt_fill_data(struct mtd_info *mtd, void *buf, int num_blocks)
+{
+ int n, n_bad_blocks = 0;
+ u32 *bb = buf + 0x8;
+ u32 *n_bad_blocksp = buf + 0x4;
+
+ for (n = 0; n < num_blocks; n++) {
+ loff_t offset = n * mtd->erasesize;
+ if (mtd_block_isbad(mtd, offset)) {
+ n_bad_blocks++;
+ *bb = n;
+ bb++;
+ }
+ }
+
+ *n_bad_blocksp = n_bad_blocks;
+
+ return n_bad_blocks;
+}
+
+static int nandbcb_update(struct mtd_info *mtd, loff_t off, size_t size,
+ size_t maxsize, const u_char *buf)
+{
+ nand_erase_options_t opts;
+ struct fcb_block *fcb;
+ struct dbbt_block *dbbt;
+ loff_t fw1_off, fw2_off;
+ void *fwbuf, *fcb_raw_page, *dbbt_page, *dbbt_data_page;
+ int nr_blks, nr_blks_fcb, nr_blks_fw, fw1_blk, fw2_blk;
+ size_t fwsize, dummy;
+ int i, ret;
+
+ /* erase */
+ memset(&opts, 0, sizeof(opts));
+ opts.offset = off;
+ opts.length = maxsize - 1;
+ ret = nand_erase_opts(mtd, &opts);
+ if (ret) {
+ printf("%s: erase failed (ret = %d)\n", __func__, ret);
+ return ret;
+ }
+
+ /*
+ * Reference documentation from i.MX6DQRM section 8.5.2.2
+ *
+ * Nand Boot Control Block(BCB) contains two data structures,
+ * - Firmware Configuration Block(FCB)
+ * - Discovered Bad Block Table(DBBT)
+ *
+ * FCB contains,
+ * - nand timings
+ * - DBBT search page address,
+ * - start page address of primary firmware
+ * - start page address of secondary firmware
+ *
+ * setup fcb:
+ * - number of blocks = mtd partition size / mtd erasesize
+ * - two firmware blocks, primary and secondary
+ * - first 4 block for FCB/DBBT
+ * - rest split in half for primary and secondary firmware
+ * - same firmware will write two times
+ */
+ nr_blks_fcb = 4;
+ nr_blks = maxsize / mtd->erasesize;
+ nr_blks_fw = (nr_blks - nr_blks_fcb) / 2;
+ fw1_blk = nr_blks_fcb;
+ fw2_blk = fw1_blk + nr_blks_fw;
+
+ /* write fw */
+ fwsize = ALIGN(size + FLASH_OFFSET_STANDARD + mtd->writesize,
+ mtd->writesize);
+ fwbuf = kzalloc(fwsize, GFP_KERNEL);
+ if (!fwbuf) {
+ debug("failed to allocate fwbuf\n");
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ memcpy(fwbuf + FLASH_OFFSET_STANDARD, buf, size);
+ fw1_off = fw1_blk * mtd->erasesize;
+ ret = nand_write_skip_bad(mtd, fw1_off, &fwsize, NULL, maxsize,
+ (u_char *)fwbuf, WITH_WR_VERIFY);
+ printf("NAND fw write: 0x%llx offset, 0x%x bytes written: %s\n",
+ fw1_off, fwsize, ret ? "ERROR" : "OK");
+ if (ret)
+ goto fwbuf_err;
+
+ /* write fw, 2nd time */
+ fw2_off = fw2_blk * mtd->erasesize;
+ ret = nand_write_skip_bad(mtd, fw2_off, &fwsize, NULL, maxsize,
+ (u_char *)fwbuf, WITH_WR_VERIFY);
+ printf("NAND fw write: 0x%llx offset, 0x%x bytes written: %s\n",
+ fw2_off, fwsize, ret ? "ERROR" : "OK");
+ if (ret)
+ goto fwbuf_err;
+
+ /* fill fcb */
+ fcb = kzalloc(sizeof(*fcb), GFP_KERNEL);
+ if (!fcb) {
+ debug("failed to allocate fcb\n");
+ ret = -ENOMEM;
+ goto fwbuf_err;
+ }
+
+ fcb->fw1_start = (fw1_blk * mtd->erasesize) / mtd->writesize;
+ fcb->fw2_start = (fw2_blk * mtd->erasesize) / mtd->writesize;
+ fcb->fw1_pages = size / mtd->writesize + 1;
+ fcb->fw2_pages = fcb->fw1_pages;
+ fill_fcb(fcb, mtd);
+
+ /* fill dbbt */
+ dbbt_page = kzalloc(mtd->writesize, GFP_KERNEL);
+ if (!dbbt_page) {
+ debug("failed to allocate dbbt_page\n");
+ ret = -ENOMEM;
+ goto fcb_err;
+ }
+
+ dbbt_data_page = kzalloc(mtd->writesize, GFP_KERNEL);
+ if (!dbbt_data_page) {
+ debug("failed to allocate dbbt_data_page\n");
+ ret = -ENOMEM;
+ goto dbbt_page_err;
+ }
+
+ dbbt = dbbt_page;
+ dbbt->checksum = 0;
+ dbbt->fingerprint = DBBT_FINGERPRINT2;
+ dbbt->version = DBBT_VERSION_1;
+ ret = dbbt_fill_data(mtd, dbbt_data_page, nr_blks);
+ if (ret < 0)
+ goto dbbt_data_page_err;
+ else if (ret > 0)
+ dbbt->dbbtnumofpages = 1;
+
+ /* write fcb/dbbt */
+ fcb_raw_page = kzalloc(mtd->writesize + mtd->oobsize, GFP_KERNEL);
+ if (!fcb_raw_page) {
+ debug("failed to allocate fcb_raw_page\n");
+ ret = -ENOMEM;
+ goto dbbt_data_page_err;
+ }
+
+ memcpy(fcb_raw_page + 12, fcb, sizeof(struct fcb_block));
+ encode_hamming_13_8(fcb_raw_page + 12, fcb_raw_page + 12 + 512, 512);
+ /*
+ * Set the first and second byte of OOB data to 0xFF, not 0x00. These
+ * bytes are used as the Manufacturers Bad Block Marker (MBBM). Since
+ * the FCB is mostly written to the first page in a block, a scan for
+ * factory bad blocks will detect these blocks as bad, e.g. when
+ * function nand_scan_bbt() is executed to build a new bad block table.
+ */
+ memset(fcb_raw_page + mtd->writesize, 0xFF, 2);
+
+ for (i = 0; i < nr_blks_fcb; i++) {
+ if (mtd_block_isbad(mtd, off)) {
+ printf("Block %d is bad, skipped\n", i);
+ continue;
+ }
+
+ /* raw write */
+ mtd_oob_ops_t ops = {
+ .datbuf = (u8 *)fcb_raw_page,
+ .oobbuf = ((u8 *)fcb_raw_page) + mtd->writesize,
+ .len = mtd->writesize,
+ .ooblen = mtd->oobsize,
+ .mode = MTD_OPS_RAW
+ };
+
+ ret = mtd_write_oob(mtd, mtd->erasesize * i, &ops);
+ if (ret)
+ goto fcb_raw_page_err;
+ debug("NAND fcb write: 0x%x offset, 0x%x bytes written: %s\n",
+ mtd->erasesize * i, ops.len, ret ? "ERROR" : "OK");
+
+ ret = mtd_write(mtd, mtd->erasesize * i + mtd->writesize,
+ mtd->writesize, &dummy, dbbt_page);
+ if (ret)
+ goto fcb_raw_page_err;
+ debug("NAND dbbt write: 0x%x offset, 0x%x bytes written: %s\n",
+ mtd->erasesize * i + mtd->writesize, dummy,
+ ret ? "ERROR" : "OK");
+
+ /* dbbtnumofpages == 0 if no bad blocks */
+ if (dbbt->dbbtnumofpages > 0) {
+ loff_t to = (mtd->erasesize * i + mtd->writesize * 5);
+
+ ret = mtd_write(mtd, to, mtd->writesize, &dummy,
+ dbbt_data_page);
+ if (ret)
+ goto fcb_raw_page_err;
+ }
+ }
+
+fcb_raw_page_err:
+ kfree(fcb_raw_page);
+dbbt_data_page_err:
+ kfree(dbbt_data_page);
+dbbt_page_err:
+ kfree(dbbt_page);
+fcb_err:
+ kfree(fcb);
+fwbuf_err:
+ kfree(fwbuf);
+err:
+ return ret;
+}
+
+static int do_nandbcb_update(int argc, char * const argv[])
+{
+ struct mtd_info *mtd;
+ loff_t addr, offset, size, maxsize;
+ char *endp;
+ u_char *buf;
+ int dev;
+ int ret;
+
+ if (argc != 4)
+ return CMD_RET_USAGE;
+
+ dev = nand_curr_device;
+ if (dev < 0) {
+ printf("failed to get nand_curr_device, run nand device");
+ return CMD_RET_FAILURE;
+ }
+
+ addr = simple_strtoul(argv[1], &endp, 16);
+ if (*argv[1] == 0 || *endp != 0)
+ return CMD_RET_FAILURE;
+
+ mtd = get_nand_dev_by_index(dev);
+ if (mtd_arg_off_size(argc - 2, argv + 2, &dev, &offset, &size,
+ &maxsize, MTD_DEV_TYPE_NAND, mtd->size))
+ return CMD_RET_FAILURE;
+
+ buf = map_physmem(addr, size, MAP_WRBACK);
+ if (!buf) {
+ puts("failed to map physical memory\n");
+ return CMD_RET_FAILURE;
+ }
+
+ ret = nandbcb_update(mtd, offset, size, maxsize, buf);
+
+ return ret == 0 ? CMD_RET_SUCCESS : CMD_RET_FAILURE;
+}
+
+static int do_nandbcb(cmd_tbl_t *cmdtp, int flag, int argc,
+ char * const argv[])
+{
+ const char *cmd;
+ int ret = 0;
+
+ if (argc < 5)
+ goto usage;
+
+ cmd = argv[1];
+ --argc;
+ ++argv;
+
+ if (strcmp(cmd, "update") == 0) {
+ ret = do_nandbcb_update(argc, argv);
+ goto done;
+ }
+
+done:
+ if (ret != -1)
+ return ret;
+usage:
+ return CMD_RET_USAGE;
+}
+
+static char nandbcb_help_text[] =
+ "update addr off|partition len - update 'len' bytes starting at\n"
+ " 'off|part' to memory address 'addr', skipping bad blocks";
+
+U_BOOT_CMD(
+ nandbcb, 5, 1, do_nandbcb,
+ "i.MX6 Nand BCB",
+ nandbcb_help_text
+);
diff --git a/doc/README.imx6 b/doc/README.imx6
index 2e8f1d8..c28f75b 100644
--- a/doc/README.imx6
+++ b/doc/README.imx6
@@ -161,3 +161,80 @@ cat u-boot-ivt.img csf-u-boot.bin > u-boot-signed.img
These two signed binaries can be used on an i.MX6 in closed
configuration when the according SRK Table Hash has been flashed.
+
+4. NAND Boot on i.MX6 with SPL support
+--------------------------------------
+
+Writing/updating boot image in nand device is not straight forward in
+i.MX6 platform and it requires boot control block(BCB) to be configured.
+
+BCB contains two data structures, Firmware Configuration Block(FCB) and
+Discovered Bad Block Table(DBBT). FCB has nand timings, DBBT search area,
+page address of primary and secondary firmware. See IMX6DQRM Section 8.5.2.2
+for more information.
+
+We can't use 'nand write' command to write SPL/firmware image directly
+like other platforms does. So we need special setup to write BCB block
+as per IMX6QDL reference manual 'nandbcb update' command do that job.
+
+for nand boot, up on reset bootrom look for FCB structure in
+first block's if FCB found the nand timings are loaded for
+further reads. once FCB read done, DTTB will load and
+finally primary or secondary firmware will load which is boot image.
+
+cmd_nandbcb will create FCB these structures
+by taking mtd partition as an example.
+- initial code will erase entire partition
+- followed by FCB setup, like first 4 block for FCB/DBBT write,
+ rest is split into two for primary and secondary firmware
+- write firmware at primary and secondary blocks(two times same image)
+- finally write fcb/dttb in first 4 block.
+
+Typical NAND BCB layout:
+=======================
+
+ no.of blocks = partition size / erasesize
+ no.of fcb/dbbt blocks = 4
+ no.of FW blocks = (no.of blocks - no.of fcb/dbbt blocks) / 2
+ FW1 offset = no.of fcb/dbbt
+ FW2 offset = FW1 offset + no.of FW blocks
+
+block 0 1 2 3 4 FW2 offset
+ ---------------------------------------------------------------
+ |FCB/DBBT 0|FCB/DBBT 1|FCB/DBBT 2|FCB/DBBT 3| FW 1 | FW 2 |
+ ----------------------------------------------------------------
+
+On summary, nandbcb update will
+- erase the entire partition
+- create BCB by creating 4 FCB/BDDT block followed by
+ 2 FW blocks based on partition size and erasesize.
+- fill FCB/DBBT structures
+- write FW/SPL in FW0 and FW1(same image in two times)
+- write FCB/DBBT in first 4 blocks
+
+step-1: write SPL
+
+icorem6qdl> fatload mmc 0:1 $loadaddr SPL
+reading SPL
+31744 bytes read in 15 ms (2 MiB/s)
+
+icorem6qdl> nandbcb update $loadaddr spl $filesize
+device 0 offset 0x0, size 0x7c00
+Erasing at 0x1c0000 -- 100% complete.
+NAND fw write: 0x100000 offset, 0x9000 bytes written: OK
+NAND fw write: 0x180000 offset, 0x9000 bytes written: OK
+
+step-2: write u-boot-dtb.img
+
+icorem6qdl> nand erase.part uboot
+NAND erase.part: device 0 offset 0x200000, size 0x200000
+Erasing at 0x3c0000 -- 100% complete.
+OK
+
+icorem6qdl> fatload mmc 0:1 $loadaddr u-boot-dtb.img
+reading u-boot-dtb.img
+508967 bytes read in 48 ms (10.1 MiB/s)
+
+icorem6qdl> nand write ${loadaddr} uboot ${filesize}
+NAND write: device 0 offset 0x200000, size 0x7c427
+508967 bytes written: OK
diff --git a/drivers/mtd/nand/mxs_nand.c b/drivers/mtd/nand/mxs_nand.c
index bed9b65..d31c3db 100644
--- a/drivers/mtd/nand/mxs_nand.c
+++ b/drivers/mtd/nand/mxs_nand.c
@@ -26,6 +26,7 @@
#include <asm/mach-imx/regs-gpmi.h>
#include <asm/arch/sys_proto.h>
#include <asm/mach-imx/dma.h>
+#include <asm/mach-imx/mxs-nand.h>
#define MXS_NAND_DMA_DESCRIPTOR_COUNT 4
@@ -150,8 +151,7 @@ static uint32_t mxs_nand_aux_status_offset(void)
return (MXS_NAND_METADATA_SIZE + 0x3) & ~0x3;
}
-static inline uint32_t mxs_nand_get_ecc_strength(uint32_t page_data_size,
- uint32_t page_oob_size)
+uint32_t mxs_nand_get_ecc_strength(u32 page_data_size, uint32_t page_oob_size)
{
int ecc_strength;
int max_ecc_strength_supported;
@@ -226,14 +226,14 @@ static inline uint32_t mxs_nand_get_mark_offset(uint32_t page_data_size,
return block_mark_bit_offset;
}
-static uint32_t mxs_nand_mark_byte_offset(struct mtd_info *mtd)
+uint32_t mxs_nand_mark_byte_offset(struct mtd_info *mtd)
{
uint32_t ecc_strength;
ecc_strength = mxs_nand_get_ecc_strength(mtd->writesize, mtd->oobsize);
return mxs_nand_get_mark_offset(mtd->writesize, ecc_strength) >> 3;
}
-static uint32_t mxs_nand_mark_bit_offset(struct mtd_info *mtd)
+uint32_t mxs_nand_mark_bit_offset(struct mtd_info *mtd)
{
uint32_t ecc_strength;
ecc_strength = mxs_nand_get_ecc_strength(mtd->writesize, mtd->oobsize);
--
2.7.4
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