diff options
Diffstat (limited to 'drivers/mtd/nand/am335x_spl_bch.c')
| -rw-r--r-- | drivers/mtd/nand/am335x_spl_bch.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/drivers/mtd/nand/am335x_spl_bch.c b/drivers/mtd/nand/am335x_spl_bch.c new file mode 100644 index 000000000..b84528ba3 --- /dev/null +++ b/drivers/mtd/nand/am335x_spl_bch.c @@ -0,0 +1,238 @@ +/* + * (C) Copyright 2012 + * Konstantin Kozhevnikov, Cogent Embedded + * + * based on nand_spl_simple code + * + * (C) Copyright 2006-2008 + * Stefan Roese, DENX Software Engineering, sr@denx.de. + * + * 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. + */ + +#include <common.h> +#include <nand.h> +#include <asm/io.h> +#include <linux/mtd/nand_ecc.h> + +static int nand_ecc_pos[] = CONFIG_SYS_NAND_ECCPOS; +static nand_info_t mtd; +static struct nand_chip nand_chip; + +#define ECCSTEPS (CONFIG_SYS_NAND_PAGE_SIZE / \ + CONFIG_SYS_NAND_ECCSIZE) +#define ECCTOTAL (ECCSTEPS * CONFIG_SYS_NAND_ECCBYTES) + + +/* + * NAND command for large page NAND devices (2k) + */ +static int nand_command(int block, int page, uint32_t offs, + u8 cmd) +{ + struct nand_chip *this = mtd.priv; + int page_addr = page + block * CONFIG_SYS_NAND_PAGE_COUNT; + void (*hwctrl)(struct mtd_info *mtd, int cmd, + unsigned int ctrl) = this->cmd_ctrl; + + while (!this->dev_ready(&mtd)) + ; + + /* Emulate NAND_CMD_READOOB */ + if (cmd == NAND_CMD_READOOB) { + offs += CONFIG_SYS_NAND_PAGE_SIZE; + cmd = NAND_CMD_READ0; + } + + /* Begin command latch cycle */ + hwctrl(&mtd, cmd, NAND_CTRL_CLE | NAND_CTRL_CHANGE); + + if (cmd == NAND_CMD_RESET) { + hwctrl(&mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE); + while (!this->dev_ready(&mtd)) + ; + return 0; + } + + /* Shift the offset from byte addressing to word addressing. */ + if (this->options & NAND_BUSWIDTH_16) + offs >>= 1; + + /* Set ALE and clear CLE to start address cycle */ + /* Column address */ + hwctrl(&mtd, offs & 0xff, + NAND_CTRL_ALE | NAND_CTRL_CHANGE); /* A[7:0] */ + hwctrl(&mtd, (offs >> 8) & 0xff, NAND_CTRL_ALE); /* A[11:9] */ + /* Row address */ + hwctrl(&mtd, (page_addr & 0xff), NAND_CTRL_ALE); /* A[19:12] */ + hwctrl(&mtd, ((page_addr >> 8) & 0xff), + NAND_CTRL_ALE); /* A[27:20] */ +#ifdef CONFIG_SYS_NAND_5_ADDR_CYCLE + /* One more address cycle for devices > 128MiB */ + hwctrl(&mtd, (page_addr >> 16) & 0x0f, + NAND_CTRL_ALE); /* A[31:28] */ +#endif + hwctrl(&mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE); + + if (cmd == NAND_CMD_READ0) { + /* Latch in address */ + hwctrl(&mtd, NAND_CMD_READSTART, + NAND_CTRL_CLE | NAND_CTRL_CHANGE); + hwctrl(&mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE); + + /* + * Wait a while for the data to be ready + */ + while (!this->dev_ready(&mtd)) + ; + } else if (cmd == NAND_CMD_RNDOUT) { + hwctrl(&mtd, NAND_CMD_RNDOUTSTART, NAND_CTRL_CLE | + NAND_CTRL_CHANGE); + hwctrl(&mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE); + } + + return 0; +} + +static int nand_is_bad_block(int block) +{ + struct nand_chip *this = mtd.priv; + + nand_command(block, 0, CONFIG_SYS_NAND_BAD_BLOCK_POS, + NAND_CMD_READOOB); + + /* + * Read one byte (or two if it's a 16 bit chip). + */ + if (this->options & NAND_BUSWIDTH_16) { + if (readw(this->IO_ADDR_R) != 0xffff) + return 1; + } else { + if (readb(this->IO_ADDR_R) != 0xff) + return 1; + } + + return 0; +} + +static int nand_read_page(int block, int page, void *dst) +{ + struct nand_chip *this = mtd.priv; + u_char ecc_calc[ECCTOTAL]; + u_char ecc_code[ECCTOTAL]; + u_char oob_data[CONFIG_SYS_NAND_OOBSIZE]; + int i; + int eccsize = CONFIG_SYS_NAND_ECCSIZE; + int eccbytes = CONFIG_SYS_NAND_ECCBYTES; + int eccsteps = ECCSTEPS; + uint8_t *p = dst; + uint32_t data_pos = 0; + uint8_t *oob = &oob_data[0] + nand_ecc_pos[0]; + uint32_t oob_pos = eccsize * eccsteps + nand_ecc_pos[0]; + + nand_command(block, page, 0, NAND_CMD_READ0); + + for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) { + this->ecc.hwctl(&mtd, NAND_ECC_READ); + nand_command(block, page, data_pos, NAND_CMD_RNDOUT); + + this->read_buf(&mtd, p, eccsize); + + nand_command(block, page, oob_pos, NAND_CMD_RNDOUT); + + this->read_buf(&mtd, oob, eccbytes); + this->ecc.calculate(&mtd, p, &ecc_calc[i]); + + data_pos += eccsize; + oob_pos += eccbytes; + oob += eccbytes; + } + + /* Pick the ECC bytes out of the oob data */ + for (i = 0; i < ECCTOTAL; i++) + ecc_code[i] = oob_data[nand_ecc_pos[i]]; + + eccsteps = ECCSTEPS; + p = dst; + + for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) { + /* No chance to do something with the possible error message + * from correct_data(). We just hope that all possible errors + * are corrected by this routine. + */ + this->ecc.correct(&mtd, p, &ecc_code[i], &ecc_calc[i]); + } + + return 0; +} + +int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst) +{ + unsigned int block, lastblock; + unsigned int page; + + /* + * offs has to be aligned to a page address! + */ + block = offs / CONFIG_SYS_NAND_BLOCK_SIZE; + lastblock = (offs + size - 1) / CONFIG_SYS_NAND_BLOCK_SIZE; + page = (offs % CONFIG_SYS_NAND_BLOCK_SIZE) / CONFIG_SYS_NAND_PAGE_SIZE; + + while (block <= lastblock) { + if (!nand_is_bad_block(block)) { + /* + * Skip bad blocks + */ + while (page < CONFIG_SYS_NAND_PAGE_COUNT) { + nand_read_page(block, page, dst); + dst += CONFIG_SYS_NAND_PAGE_SIZE; + page++; + } + + page = 0; + } else { + lastblock++; + } + + block++; + } + + return 0; +} + +/* nand_init() - initialize data to make nand usable by SPL */ +void nand_init(void) +{ + /* + * Init board specific nand support + */ + mtd.priv = &nand_chip; + nand_chip.IO_ADDR_R = nand_chip.IO_ADDR_W = + (void __iomem *)CONFIG_SYS_NAND_BASE; + board_nand_init(&nand_chip); + + if (nand_chip.select_chip) + nand_chip.select_chip(&mtd, 0); + + /* NAND chip may require reset after power-on */ + nand_command(0, 0, 0, NAND_CMD_RESET); +} + +/* Unselect after operation */ +void nand_deselect(void) +{ + if (nand_chip.select_chip) + nand_chip.select_chip(&mtd, -1); +} |