From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Frysinger Date: Tue, 31 Jan 2012 14:53:33 -0500 Subject: [U-Boot] [PATCH 4/5 v2] sandbox: new SPI flash driver In-Reply-To: <1328039614-10031-1-git-send-email-vapier@gentoo.org> References: <1328039614-10031-1-git-send-email-vapier@gentoo.org> Message-ID: <1328039614-10031-5-git-send-email-vapier@gentoo.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de This adds a SPI flash driver which simulates SPI flash clients. Currently supports the bare min that U-Boot requires: you can probe, read, erase, and write. Should be easy to extend to make it behave more exactly like a real SPI flash, but this is good enough to merge now. Signed-off-by: Mike Frysinger --- drivers/mtd/spi/Makefile | 1 + drivers/mtd/spi/sandbox.c | 386 +++++++++++++++++++++++++++++++++++++++++++++ drivers/spi/sandbox_spi.c | 5 + 3 files changed, 392 insertions(+), 0 deletions(-) create mode 100644 drivers/mtd/spi/sandbox.c diff --git a/drivers/mtd/spi/Makefile b/drivers/mtd/spi/Makefile index 90f8392..fb37807 100644 --- a/drivers/mtd/spi/Makefile +++ b/drivers/mtd/spi/Makefile @@ -33,6 +33,7 @@ COBJS-$(CONFIG_SPI_FLASH) += spi_flash.o COBJS-$(CONFIG_SPI_FLASH_ATMEL) += atmel.o COBJS-$(CONFIG_SPI_FLASH_EON) += eon.o COBJS-$(CONFIG_SPI_FLASH_MACRONIX) += macronix.o +COBJS-$(CONFIG_SPI_FLASH_SANDBOX) += sandbox.o COBJS-$(CONFIG_SPI_FLASH_SPANSION) += spansion.o COBJS-$(CONFIG_SPI_FLASH_SST) += sst.o COBJS-$(CONFIG_SPI_FLASH_STMICRO) += stmicro.o diff --git a/drivers/mtd/spi/sandbox.c b/drivers/mtd/spi/sandbox.c new file mode 100644 index 0000000..4b8e384 --- /dev/null +++ b/drivers/mtd/spi/sandbox.c @@ -0,0 +1,386 @@ +/* + * Simulate a SPI flash + * + * Copyright (c) 2011-2012 The Chromium OS Authors. + * See file CREDITS for list of people who contributed to this + * project. + * + * Licensed under the GPL-2 or later. + */ + +#include +#include +#include +#include + +#include +#include "spi_flash_internal.h" + +#include + +/* + * The different states that our SPI flash transitions between. + * We need to keep track of this across multiple xfer calls since + * the SPI bus could possibly call down into us multiple times. + */ +typedef enum { + SF_CMD, /* default state -- we're awaiting a command */ + SF_ID, /* read the flash's (jedec) ID code */ + SF_ADDR, /* processing the offset in the flash to read/etc... */ + SF_READ, /* reading data from the flash */ + SF_WRITE, /* writing data to the flash, i.e. page programming */ + SF_ERASE, /* erase the flash */ + SF_READ_STATUS, /* read the flash's status register */ +} sb_sf_state; + +static const char *sb_sf_state_name(sb_sf_state state) +{ + static const char * const states[] = { + "CMD", "ID", "ADDR", "READ", "WRITE", "ERASE", "READ_STATUS", + }; + return states[state]; +} + +/* Bits for the status register */ +#define STAT_WIP (1 << 0) +#define STAT_WEL (1 << 1) + +/* Assume all SPI flashes have 3 byte addresses since they do atm */ +#define SF_ADDR_LEN 3 + +struct sb_spi_flash_erase_commands { + u8 cmd; + u32 size; +}; +#define IDCODE_LEN 5 +#define MAX_ERASE_CMDS 2 +struct sb_spi_flash_data { + const char *name; + u8 idcode[IDCODE_LEN]; + u32 size; + const struct sb_spi_flash_erase_commands erase_cmds[MAX_ERASE_CMDS]; +}; + +/* Structure describing all the flashes we know how to emulate */ +static const struct sb_spi_flash_data sb_sf_flashes[] = { + { + "M25P16", { 0x20, 0x20, 0x15 }, (2 * 1024 * 1024), + { /* erase commands */ + { 0xd8, (64 * 1024), }, /* sector */ + { 0xc7, (2 * 1024 * 1024), }, /* bulk */ + }, + }, +}; + +/* Used to quickly bulk erase backing store */ +static u8 sb_sf_0xff[0x10000]; + +/* Internal state data for each SPI flash */ +struct sb_spi_flash { + /* + * As we receive data over the SPI bus, our flash transitions + * between states. For example, we start off in the SF_CMD + * state where the first byte tells us what operation to perform + * (such as read or write the flash). But the operation itself + * can go through a few states such as first reading in the + * offset in the flash to perform the requested operation. + * Thus "state" stores the exact state that our machine is in + * while "cmd" stores the overall command we're processing. + */ + sb_sf_state state; + uint cmd; + const void *cmd_data; + /* Current position in the flash; used when reading/writing/etc... */ + uint off; + /* How many address bytes we've consumed */ + uint addr_bytes, pad_addr_bytes; + /* The current flash status (see STAT_XXX defines above) */ + u8 status; + /* Data describing the flash we're emulating */ + const struct sb_spi_flash_data *data; + /* The file on disk to serv up data from */ + int fd; +}; + +static int sb_sf_setup(void **priv, const char *spec) +{ + /* spec = idcode:file */ + struct sb_spi_flash *sbsf; + const char *file; + size_t i, len, idname_len; + const struct sb_spi_flash_data *data; + + file = strchr(spec, ':'); + if (!file) + goto error; + idname_len = file - spec; + ++file; + + for (i = 0; i < ARRAY_SIZE(sb_sf_flashes); ++i) { + data = &sb_sf_flashes[i]; + len = strlen(data->name); + if (idname_len != len) + continue; + if (!memcmp(spec, data->name, len)) + break; + } + if (i == ARRAY_SIZE(sb_sf_flashes)) { + printf("sb_sf: unknown flash '%*s'\n", + (int)idname_len, file); + goto error; + } + + if (sb_sf_0xff[0] == 0x00) + memset(sb_sf_0xff, 0xff, sizeof(sb_sf_0xff)); + + sbsf = malloc(sizeof(*sbsf)); + if (!sbsf) + goto error; + + sbsf->fd = os_open(file, 02); + if (sbsf->fd == -1) { + free(sbsf); + goto error; + } + + sbsf->data = data; + + *priv = sbsf; + return 0; + + error: + printf("sb_sf: unable to parse client spec\n"); + return 1; +} + +static void sb_sf_free(void *priv) +{ + struct sb_spi_flash *sbsf = priv; + + os_close(sbsf->fd); + free(sbsf); +} + +static void sb_sf_cs_activate(void *priv) +{ + struct sb_spi_flash *sbsf = priv; + + debug("sb_sf: CS activated; state is fresh!\n"); + + /* CS is asserted, so reset state */ + sbsf->off = 0; + sbsf->addr_bytes = 0; + sbsf->pad_addr_bytes = 0; + sbsf->state = sbsf->cmd = SF_CMD; +} + +static void sb_sf_cs_deactivate(void *priv) +{ + debug("sb_sf: CS deactivated; cmd done processing!\n"); +} + +/* Figure out what command this stream is telling us to do */ +static int sb_sf_process_cmd(struct sb_spi_flash *sbsf, const u8 *rx, u8 *tx) +{ + sb_sf_state oldstate = sbsf->state; + + /* We need to output a byte for the cmd byte we just ate */ + sb_spi_tristate(tx, 1); + + sbsf->cmd = rx[0]; + switch (sbsf->cmd) { + case CMD_READ_ID: + sbsf->state = sbsf->cmd = SF_ID; + break; + case CMD_READ_ARRAY_FAST: + sbsf->pad_addr_bytes = 1; + case CMD_READ_ARRAY_SLOW: + case CMD_PAGE_PROGRAM: + state_addr: + sbsf->state = SF_ADDR; + break; + case CMD_WRITE_DISABLE: + debug(" write disabled\n"); + sbsf->status &= ~STAT_WEL; + break; + case CMD_READ_STATUS: + sbsf->state = SF_READ_STATUS; + break; + case CMD_WRITE_ENABLE: + debug(" write enabled\n"); + sbsf->status |= STAT_WEL; + break; + default: { + size_t i; + + /* handle erase commands first */ + for (i = 0; i < MAX_ERASE_CMDS; ++i) { + const struct sb_spi_flash_erase_commands *erase_cmd = + &sbsf->data->erase_cmds[i]; + + if (erase_cmd->cmd == 0x00) + continue; + if (sbsf->cmd != erase_cmd->cmd) + continue; + + sbsf->cmd_data = erase_cmd; + goto state_addr; + } + + debug(" cmd unknown: %#x\n", sbsf->cmd); + return 1; + } + } + + if (oldstate != sbsf->state) + debug(" cmd: transition to %s state\n", + sb_sf_state_name(sbsf->state)); + + return 0; +} + +static int sb_sf_xfer(void *priv, const u8 *rx, u8 *tx, + uint bytes) +{ + struct sb_spi_flash *sbsf = priv; + uint cnt, pos = 0; + + debug("sb_sf: state:%x(%s) bytes:%u\n", sbsf->state, + sb_sf_state_name(sbsf->state), bytes); + + if (sbsf->state == SF_CMD) { + /* Figure out the initial state */ + if (sb_sf_process_cmd(sbsf, rx, tx)) + return 1; + ++pos; + } + + /* Process the remaining data */ + while (pos < bytes) { + switch (sbsf->state) { + case SF_ID: { + u8 id; + + debug(" id: off:%u tx:", sbsf->off); + if (sbsf->off < IDCODE_LEN) + id = sbsf->data->idcode[sbsf->off]; + else + id = 0; + debug("%02x\n", id); + tx[pos++] = id; + ++sbsf->off; + break; + } + case SF_ADDR: + debug(" addr: bytes:%u rx:%02x ", + sbsf->addr_bytes, rx[pos]); + + if (sbsf->addr_bytes++ < SF_ADDR_LEN) + sbsf->off = (sbsf->off << 8) | rx[pos]; + debug("addr:%06x\n", sbsf->off); + + sb_spi_tristate(&tx[pos++], 1); + + /* See if we're done processing */ + if (sbsf->addr_bytes < SF_ADDR_LEN + sbsf->pad_addr_bytes) + break; + + /* Next state! */ + os_lseek(sbsf->fd, sbsf->off, OS_SEEK_SET); + switch (sbsf->cmd) { + case CMD_READ_ARRAY_FAST: + case CMD_READ_ARRAY_SLOW: + sbsf->state = SF_READ; + break; + case CMD_PAGE_PROGRAM: + sbsf->state = SF_WRITE; + break; + default: + /* assume erase state ... */ + sbsf->state = SF_ERASE; + goto case_SF_ERASE; + } + debug(" cmd: transition to %s state\n", + sb_sf_state_name(sbsf->state)); + break; + case SF_READ: + /* + * XXX: need to handle exotic behavior: + * - reading past end of device + */ + + cnt = bytes - pos; + debug(" tx: read(%u)\n", cnt); + pos += os_read(sbsf->fd, tx + pos, cnt); + break; + case SF_READ_STATUS: + debug(" read status: %#x\n", sbsf->status); + cnt = bytes - pos; + memset(tx + pos, sbsf->status, cnt); + pos += cnt; + break; + case SF_WRITE: + /* + * XXX: need to handle exotic behavior: + * - unaligned addresses + * - more than a page (256) worth of data + * - reading past end of device + */ + + if (!(sbsf->status & STAT_WEL)) { + puts("sb_sf: write enable not set before erase\n"); + goto done; + } + + cnt = bytes - pos; + debug(" rx: write(%u)\n", cnt); + sb_spi_tristate(&tx[pos], cnt); + pos += os_write(sbsf->fd, rx + pos, cnt); + sbsf->status &= ~STAT_WEL; + break; + case SF_ERASE: + case_SF_ERASE: { + const struct sb_spi_flash_erase_commands *erase_cmd = + sbsf->cmd_data; + + if (!(sbsf->status & STAT_WEL)) { + puts("sb_sf: write enable not set before erase\n"); + goto done; + } + + /* verify address is aligned */ + if (sbsf->off & ~(erase_cmd->size - 1)) { + debug(" sector erase: cmd:%#x needs align:%#x, but we got %#x\n", + erase_cmd->cmd, erase_cmd->size, sbsf->off); + sbsf->status &= ~STAT_WEL; + goto done; + } + + debug(" sector erase addr: %u\n", sbsf->off); + + cnt = bytes - pos; + sb_spi_tristate(&tx[pos], cnt); + pos += cnt; + + /* XXX: latch WIP in status, and delay before clearing it ? */ + os_write(sbsf->fd, sb_sf_0xff, erase_cmd->size); + sbsf->status &= ~STAT_WEL; + goto done; + } + default: + debug(" ??? no idea what to do ???\n"); + goto done; + } + } + + done: + return pos == bytes ? 0 : 1; +} + +const struct sb_spi_emu_ops sb_sf_ops = { + .setup = sb_sf_setup, + .free = sb_sf_free, + .cs_activate = sb_sf_cs_activate, + .cs_deactivate = sb_sf_cs_deactivate, + .xfer = sb_sf_xfer, +}; diff --git a/drivers/spi/sandbox_spi.c b/drivers/spi/sandbox_spi.c index d0cba76..88b51ab 100644 --- a/drivers/spi/sandbox_spi.c +++ b/drivers/spi/sandbox_spi.c @@ -35,10 +35,15 @@ static const char *sb_lookup_arg(unsigned int bus, unsigned int cs) return os_getopt(sf_arg, 1); } +extern const struct sb_spi_emu_ops sb_sf_ops; + static const struct { const char *spec; const struct sb_spi_emu_ops *ops; } sb_emu_map[] = { +#ifdef CONFIG_SPI_FLASH_SANDBOX + { "sf", &sb_sf_ops, }, +#endif }; static int sb_parse_type(struct sb_spi_slave *sss) -- 1.7.8.4