From e99ca98f1d7190c16601b00d0c96212d7c00577d Mon Sep 17 00:00:00 2001 From: Ricardo Ribalda Date: Fri, 2 Dec 2016 12:31:44 +0100 Subject: [PATCH] mtd: spi-nor: Add support for S3AN spi-nor devices Xilinx Spartan-3AN FPGAs contain an In-System Flash where they keep their configuration data and (optionally) some user data. The protocol of this flash follows most of the spi-nor standard. With the following differences: - Page size might not be a power of two. - The address calculation (default addressing mode). - The spi nor commands used. Protocol is described on Xilinx User Guide UG333 Signed-off-by: Ricardo Ribalda Delgado Cc: Boris Brezillon Cc: Brian Norris Cc: Marek Vasut Reviewed-by: Marek Vasut Signed-off-by: Cyrille Pitchen --- drivers/mtd/spi-nor/spi-nor.c | 154 ++++++++++++++++++++++++++++++++-- include/linux/mtd/spi-nor.h | 12 +++ 2 files changed, 161 insertions(+), 5 deletions(-) diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index da7cd69d4857..be1d41d21d7d 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -75,6 +75,12 @@ struct flash_info { * bit. Must be used with * SPI_NOR_HAS_LOCK. */ +#define SPI_S3AN BIT(10) /* + * Xilinx Spartan 3AN In-System Flash + * (MFR cannot be used for probing + * because it has the same value as + * ATMEL flashes) + */ }; #define JEDEC_MFR(info) ((info)->id[0]) @@ -217,6 +223,21 @@ static inline int set_4byte(struct spi_nor *nor, const struct flash_info *info, return nor->write_reg(nor, SPINOR_OP_BRWR, nor->cmd_buf, 1); } } + +static int s3an_sr_ready(struct spi_nor *nor) +{ + int ret; + u8 val; + + ret = nor->read_reg(nor, SPINOR_OP_XRDSR, &val, 1); + if (ret < 0) { + dev_err(nor->dev, "error %d reading XRDSR\n", (int) ret); + return ret; + } + + return !!(val & XSR_RDY); +} + static inline int spi_nor_sr_ready(struct spi_nor *nor) { int sr = read_sr(nor); @@ -238,7 +259,11 @@ static inline int spi_nor_fsr_ready(struct spi_nor *nor) static int spi_nor_ready(struct spi_nor *nor) { int sr, fsr; - sr = spi_nor_sr_ready(nor); + + if (nor->flags & SNOR_F_READY_XSR_RDY) + sr = s3an_sr_ready(nor); + else + sr = spi_nor_sr_ready(nor); if (sr < 0) return sr; fsr = nor->flags & SNOR_F_USE_FSR ? spi_nor_fsr_ready(nor) : 1; @@ -319,6 +344,24 @@ static void spi_nor_unlock_and_unprep(struct spi_nor *nor, enum spi_nor_ops ops) mutex_unlock(&nor->lock); } +/* + * This code converts an address to the Default Address Mode, that has non + * power of two page sizes. We must support this mode because it is the default + * mode supported by Xilinx tools, it can access the whole flash area and + * changing over to the Power-of-two mode is irreversible and corrupts the + * original data. + * Addr can safely be unsigned int, the biggest S3AN device is smaller than + * 4 MiB. + */ +static loff_t spi_nor_s3an_addr_convert(struct spi_nor *nor, unsigned int addr) +{ + unsigned int offset = addr; + + offset %= nor->page_size; + + return ((addr - offset) << 1) | offset; +} + /* * Initiate the erasure of a single sector */ @@ -327,6 +370,9 @@ static int spi_nor_erase_sector(struct spi_nor *nor, u32 addr) u8 buf[SPI_NOR_MAX_ADDR_WIDTH]; int i; + if (nor->flags & SNOR_F_S3AN_ADDR_DEFAULT) + addr = spi_nor_s3an_addr_convert(nor, addr); + if (nor->erase) return nor->erase(nor, addr); @@ -368,7 +414,7 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) return ret; /* whole-chip erase? */ - if (len == mtd->size) { + if (len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) { unsigned long timeout; write_enable(nor); @@ -782,6 +828,19 @@ static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len) .addr_width = (_addr_width), \ .flags = (_flags), +#define S3AN_INFO(_jedec_id, _n_sectors, _page_size) \ + .id = { \ + ((_jedec_id) >> 16) & 0xff, \ + ((_jedec_id) >> 8) & 0xff, \ + (_jedec_id) & 0xff \ + }, \ + .id_len = 3, \ + .sector_size = (8*_page_size), \ + .n_sectors = (_n_sectors), \ + .page_size = _page_size, \ + .addr_width = 3, \ + .flags = SPI_NOR_NO_FR | SPI_S3AN, + /* NOTE: double check command sets and memory organization when you add * more nor chips. This current list focusses on newer chips, which * have been converging on command sets which including JEDEC ID. @@ -1014,6 +1073,13 @@ static const struct flash_info spi_nor_ids[] = { { "cat25c09", CAT25_INFO( 128, 8, 32, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) }, { "cat25c17", CAT25_INFO( 256, 8, 32, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) }, { "cat25128", CAT25_INFO(2048, 8, 64, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) }, + + /* Xilinx S3AN Internal Flash */ + { "3S50AN", S3AN_INFO(0x1f2200, 64, 264) }, + { "3S200AN", S3AN_INFO(0x1f2400, 256, 264) }, + { "3S400AN", S3AN_INFO(0x1f2400, 256, 264) }, + { "3S700AN", S3AN_INFO(0x1f2500, 512, 264) }, + { "3S1400AN", S3AN_INFO(0x1f2600, 512, 528) }, { }, }; @@ -1054,7 +1120,12 @@ static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len, return ret; while (len) { - ret = nor->read(nor, from, len, buf); + loff_t addr = from; + + if (nor->flags & SNOR_F_S3AN_ADDR_DEFAULT) + addr = spi_nor_s3an_addr_convert(nor, addr); + + ret = nor->read(nor, addr, len, buf); if (ret == 0) { /* We shouldn't see 0-length reads */ ret = -EIO; @@ -1175,8 +1246,23 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len, for (i = 0; i < len; ) { ssize_t written; + loff_t addr = to + i; - page_offset = (to + i) & (nor->page_size - 1); + /* + * If page_size is a power of two, the offset can be quickly + * calculated with an AND operation. On the other cases we + * need to do a modulus operation (more expensive). + * Power of two numbers have only one bit set and we can use + * the instruction hweight32 to detect if we need to do a + * modulus (do_div()) or not. + */ + if (hweight32(nor->page_size) == 1) { + page_offset = addr & (nor->page_size - 1); + } else { + uint64_t aux = addr; + + page_offset = do_div(aux, nor->page_size); + } WARN_ONCE(page_offset, "Writing at offset %zu into a NOR page. Writing partial pages may decrease reliability and increase wear of NOR flash.", page_offset); @@ -1184,8 +1270,11 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len, page_remain = min_t(size_t, nor->page_size - page_offset, len - i); + if (nor->flags & SNOR_F_S3AN_ADDR_DEFAULT) + addr = spi_nor_s3an_addr_convert(nor, addr); + write_enable(nor); - ret = nor->write(nor, to + i, page_remain, buf + i); + ret = nor->write(nor, addr, page_remain, buf + i); if (ret < 0) goto write_err; written = ret; @@ -1312,6 +1401,47 @@ static int spi_nor_check(struct spi_nor *nor) return 0; } +static int s3an_nor_scan(const struct flash_info *info, struct spi_nor *nor) +{ + int ret; + u8 val; + + ret = nor->read_reg(nor, SPINOR_OP_XRDSR, &val, 1); + if (ret < 0) { + dev_err(nor->dev, "error %d reading XRDSR\n", (int) ret); + return ret; + } + + nor->erase_opcode = SPINOR_OP_XSE; + nor->program_opcode = SPINOR_OP_XPP; + nor->read_opcode = SPINOR_OP_READ; + nor->flags |= SNOR_F_NO_OP_CHIP_ERASE; + + /* + * This flashes have a page size of 264 or 528 bytes (known as + * Default addressing mode). It can be changed to a more standard + * Power of two mode where the page size is 256/512. This comes + * with a price: there is 3% less of space, the data is corrupted + * and the page size cannot be changed back to default addressing + * mode. + * + * The current addressing mode can be read from the XRDSR register + * and should not be changed, because is a destructive operation. + */ + if (val & XSR_PAGESIZE) { + /* Flash in Power of 2 mode */ + nor->page_size = (nor->page_size == 264) ? 256 : 512; + nor->mtd.writebufsize = nor->page_size; + nor->mtd.size = 8 * nor->page_size * info->n_sectors; + nor->mtd.erasesize = 8 * nor->page_size; + } else { + /* Flash in Default addressing mode */ + nor->flags |= SNOR_F_S3AN_ADDR_DEFAULT; + } + + return 0; +} + int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) { const struct flash_info *info = NULL; @@ -1359,6 +1489,14 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) mutex_init(&nor->lock); + /* + * Make sure the XSR_RDY flag is set before calling + * spi_nor_wait_till_ready(). Xilinx S3AN share MFR + * with Atmel spi-nor + */ + if (info->flags & SPI_S3AN) + nor->flags |= SNOR_F_READY_XSR_RDY; + /* * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up * with the software protection bits set @@ -1517,6 +1655,12 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) nor->read_dummy = spi_nor_read_dummy_cycles(nor); + if (info->flags & SPI_S3AN) { + ret = s3an_nor_scan(info, nor); + if (ret) + return ret; + } + dev_info(dev, "%s (%lld Kbytes)\n", info->name, (long long)mtd->size >> 10); diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index c425c7b4c2a0..4950b2ef08c0 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -68,6 +68,15 @@ #define SPINOR_OP_WRDI 0x04 /* Write disable */ #define SPINOR_OP_AAI_WP 0xad /* Auto address increment word program */ +/* Used for S3AN flashes only */ +#define SPINOR_OP_XSE 0x50 /* Sector erase */ +#define SPINOR_OP_XPP 0x82 /* Page program */ +#define SPINOR_OP_XRDSR 0xd7 /* Read status register */ + +#define XSR_PAGESIZE BIT(0) /* Page size in Po2 or Linear */ +#define XSR_RDY BIT(7) /* Ready */ + + /* Used for Macronix and Winbond flashes. */ #define SPINOR_OP_EN4B 0xb7 /* Enter 4-byte mode */ #define SPINOR_OP_EX4B 0xe9 /* Exit 4-byte mode */ @@ -119,6 +128,9 @@ enum spi_nor_ops { enum spi_nor_option_flags { SNOR_F_USE_FSR = BIT(0), SNOR_F_HAS_SR_TB = BIT(1), + SNOR_F_NO_OP_CHIP_ERASE = BIT(2), + SNOR_F_S3AN_ADDR_DEFAULT = BIT(3), + SNOR_F_READY_XSR_RDY = BIT(4), }; /** -- 2.20.1