[U-Boot] [PATCH 4/6] sandbox: new SPI flash driver
Mike Frysinger
vapier at gentoo.org
Mon Jan 23 07:30:26 CET 2012
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 <vapier at gentoo.org>
---
drivers/mtd/spi/Makefile | 1 +
drivers/mtd/spi/sandbox.c | 318 +++++++++++++++++++++++++++++++++++++++++++++
drivers/spi/sandbox_spi.c | 5 +
3 files changed, 324 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..a1bb641
--- /dev/null
+++ b/drivers/mtd/spi/sandbox.c
@@ -0,0 +1,318 @@
+/*
+ * 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 <common.h>
+#include <malloc.h>
+#include <spi.h>
+#include <os.h>
+
+#include <spi_flash.h>
+#include "spi_flash_internal.h"
+
+#include <asm/spi.h>
+
+typedef enum {
+ SF_CMD, SF_ID, SF_READ, SF_WRITE, SF_ERASE, SF_READ_STATUS, SF_WREN, SF_WRDI,
+} sb_sf_state;
+
+#define STAT_WIP (1 << 0)
+#define STAT_WEL (1 << 1)
+
+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];
+};
+
+struct sb_spi_flash {
+ sb_sf_state state;
+ uint off;
+ const struct sb_spi_flash_data *data;
+ int fd;
+ u8 status;
+};
+
+static const char *sb_sf_state_name(sb_sf_state state)
+{
+ static const char * const states[] = {
+ "CMD", "ID", "READ", "WRITE", "ERASE", "READ_STATUS", "WREN", "WRDI",
+ };
+ return states[state];
+}
+
+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 */
+ },
+ },
+};
+
+static u8 sb_sf_0xff[0x10000];
+
+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("sandbox_spi_flash: 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->state = SF_CMD;
+ sbsf->data = data;
+
+ *priv = sbsf;
+ return 0;
+
+ error:
+ printf("sandbox_spi_flash: 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_deactivate(void *priv)
+{
+ struct sb_spi_flash *sbsf = priv;
+
+ /* CS is no longer being asserted, so reset state */
+ sbsf->state = SF_CMD;
+}
+
+static int sb_sf_xfer(void *priv, const u8 *tx, u8 *rx,
+ uint bytes)
+{
+ struct sb_spi_flash *sbsf = priv;
+ uint i, written = 0;
+
+ debug("sb_sf: state:%x(%s) bytes:%u\n", sbsf->state,
+ sb_sf_state_name(sbsf->state), bytes);
+
+ if (sbsf->state == SF_CMD) {
+ sb_sf_state oldstate = sbsf->state;
+
+ rx[written++] = 0;
+ sb_spi_tristate(rx, 1);
+
+ /*
+ * XXX: we assume cmds that need addresses get them in one
+ * transfer rather than accumulating ... but u-boot
+ * doesn't care at all.
+ */
+
+ switch (tx[0]) {
+ case CMD_READ_ID:
+ sbsf->off = 0;
+ sbsf->state = SF_ID;
+ break;
+ case CMD_PAGE_PROGRAM:
+ /* XXX: check WEL in status */
+
+ /*
+ * XXX: need to handle exotic behavior:
+ * - unaligned addresses
+ * - too big of an address
+ */
+
+ sbsf->off = (tx[1] << 16) | (tx[2] << 8) | tx[3];
+ os_lseek(sbsf->fd, sbsf->off, 0);
+
+ written += 3;
+ sb_spi_tristate(&rx[1], 3);
+
+ sbsf->state = SF_WRITE;
+ sbsf->status &= ~STAT_WEL;
+ break;
+ case CMD_READ_ARRAY_SLOW:
+ case CMD_READ_ARRAY_FAST: {
+ uint alen = 3;
+
+ sbsf->off = (tx[1] << 16) | (tx[2] << 8) | tx[3];
+ os_lseek(sbsf->fd, sbsf->off, 0);
+ debug(" read addr: %u\n", sbsf->off);
+
+ if (tx[0] == CMD_READ_ARRAY_FAST)
+ /* read fast needs a dummy byte */
+ ++alen;
+
+ written += alen;
+ sb_spi_tristate(&rx[1], alen);
+
+ sbsf->state = SF_READ;
+ 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:
+ /* 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 (tx[0] != erase_cmd->cmd)
+ continue;
+
+ /* XXX: check WEL in status */
+
+ /* verify address is aligned */
+ sbsf->off = (tx[1] << 16) | (tx[2] << 8) | tx[3];
+ 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;
+ return 1;
+ }
+
+ os_lseek(sbsf->fd, sbsf->off, 0);
+ debug(" sector erase addr: %u\n", sbsf->off);
+
+ written += 3;
+ sb_spi_tristate(&rx[1], 3);
+
+ /* 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 cmd_done;
+ }
+
+ debug(" cmd unknown: %#x\n", tx[0]);
+ return 1;
+ }
+
+ cmd_done:
+ if (oldstate != sbsf->state)
+ debug(" cmd: transition to %s state\n",
+ sb_sf_state_name(sbsf->state));
+ }
+
+ if (written == bytes)
+ return 0;
+
+ switch (sbsf->state) {
+ case SF_ID: {
+ const u8 *idcode = sbsf->data->idcode;
+
+ debug(" id: off:%u\n tx:", sbsf->off);
+ for (i = sbsf->off; i < IDCODE_LEN; ++i) {
+ if (written < bytes) {
+ rx[written++] = idcode[i];
+ debug(" %02x", idcode[i]);
+ } else
+ break;
+ }
+ if (written < bytes) {
+ i = bytes - written;
+ debug(" <memset remaining %u bytes>", i);
+ memset(rx + written, 0, i);
+ written += i;
+ }
+ debug("\n");
+ break;
+ }
+ case SF_READ:
+ /*
+ * XXX: need to handle exotic behavior:
+ * - reading past end of device
+ */
+ i = bytes - written;
+ debug(" tx: read(%u)\n", i);
+ if (i)
+ written += os_read(sbsf->fd, rx + written, i);
+ break;
+ case SF_READ_STATUS:
+ debug(" read status: %#x\n", sbsf->status);
+ i = bytes - written;
+ memset(rx + written, sbsf->status, i);
+ written += i;
+ break;
+ case SF_WRITE:
+ /*
+ * XXX: need to handle exotic behavior:
+ * - more than a page (256) worth of data
+ * - reading past end of device
+ */
+ i = bytes - written;
+ debug(" rx: write(%u)\n", i);
+ if (i)
+ written += os_write(sbsf->fd, tx + written, i);
+ break;
+ default:
+ debug(" ??? no idea what to do ???\n");
+ break;
+ }
+
+ return written == bytes ? 0 : 1;
+}
+
+const struct sb_spi_emu_ops sb_sf_ops = {
+ .setup = sb_sf_setup,
+ .free = sb_sf_free,
+ .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 eda0f3e..ae15946 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)
--
1.7.8.3
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