cfi: support for 16-bit flash with reversed endianness

This is for targets where flash controller has reverse endianness
compared to target.  For these, the 'bus_swap' parameter can be given to the
CFI driver, which will cause command CFI commands to be written with
bytes swapped.  This is only for x16 CFI flash.

Change-Id: I698b768e92e65d160232e90b0e81a824e3c81a46
Signed-off-by: Esben Haabendal <esben@haabendal.dk>
Reviewed-on: http://openocd.zylin.com/3041
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

diff --git a/doc/openocd.texi b/doc/openocd.texi
index 2e451140ee706bc7bb3d16ff564030d044d208ed..acda084d94e98d2a98ee4a800fda8f5010f76f1f 100644 (file)
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -4806,6 +4806,7 @@ The CFI driver can accept the following optional parameters, in any order:
 @item @var{jedec_probe} ... is used to detect certain non-CFI flash ROMs,
 like AM29LV010 and similar types.
 @item @var{x16_as_x8} ... when a 16-bit flash is hooked up to an 8-bit bus.
+@item @var{bus_swap} ... when data bytes in a 16-bit flash needs to be swapped.
 @end itemize
 
 To configure two adjacent banks of 16 MBytes each, both sixteen bits (two bytes)

diff --git a/src/flash/nor/cfi.c b/src/flash/nor/cfi.c
index efa0aeecf00a5c96aca8f43e039e6a1247f90d71..b808830010250e1731cc3ced3d22021a53207925 100644 (file)
--- a/src/flash/nor/cfi.c
+++ b/src/flash/nor/cfi.c
@@ -136,6 +136,7 @@ static inline uint32_t flash_address(struct flash_bank *bank, int sector, uint32
 static void cfi_command(struct flash_bank *bank, uint8_t cmd, uint8_t *cmd_buf)
 {
        int i;
+       struct cfi_flash_bank *cfi_info = bank->driver_priv;
 
        /* clear whole buffer, to ensure bits that exceed the bus_width
         * are set to zero
@@ -143,7 +144,7 @@ static void cfi_command(struct flash_bank *bank, uint8_t cmd, uint8_t *cmd_buf)
        for (i = 0; i < CFI_MAX_BUS_WIDTH; i++)
                cmd_buf[i] = 0;
 
-       if (bank->target->endianness == TARGET_LITTLE_ENDIAN) {
+       if (cfi_info->endianness == TARGET_LITTLE_ENDIAN) {
                for (i = bank->bus_width; i > 0; i--)
                        *cmd_buf++ = (i & (bank->chip_width - 1)) ? 0x0 : cmd;
        } else {
@@ -167,6 +168,7 @@ static int cfi_send_command(struct flash_bank *bank, uint8_t cmd, uint32_t addre
 static int cfi_query_u8(struct flash_bank *bank, int sector, uint32_t offset, uint8_t *val)
 {
        struct target *target = bank->target;
+       struct cfi_flash_bank *cfi_info = bank->driver_priv;
        uint8_t data[CFI_MAX_BUS_WIDTH];
 
        int retval;
@@ -175,7 +177,7 @@ static int cfi_query_u8(struct flash_bank *bank, int sector, uint32_t offset, ui
        if (retval != ERROR_OK)
                return retval;
 
-       if (bank->target->endianness == TARGET_LITTLE_ENDIAN)
+       if (cfi_info->endianness == TARGET_LITTLE_ENDIAN)
                *val = data[0];
        else
                *val = data[bank->bus_width - 1];
@@ -190,6 +192,7 @@ static int cfi_query_u8(struct flash_bank *bank, int sector, uint32_t offset, ui
 static int cfi_get_u8(struct flash_bank *bank, int sector, uint32_t offset, uint8_t *val)
 {
        struct target *target = bank->target;
+       struct cfi_flash_bank *cfi_info = bank->driver_priv;
        uint8_t data[CFI_MAX_BUS_WIDTH];
        int i;
 
@@ -199,7 +202,7 @@ static int cfi_get_u8(struct flash_bank *bank, int sector, uint32_t offset, uint
        if (retval != ERROR_OK)
                return retval;
 
-       if (bank->target->endianness == TARGET_LITTLE_ENDIAN) {
+       if (cfi_info->endianness == TARGET_LITTLE_ENDIAN) {
                for (i = 0; i < bank->bus_width / bank->chip_width; i++)
                        data[0] |= data[i];
 
@@ -236,7 +239,7 @@ static int cfi_query_u16(struct flash_bank *bank, int sector, uint32_t offset, u
                        return retval;
        }
 
-       if (bank->target->endianness == TARGET_LITTLE_ENDIAN)
+       if (cfi_info->endianness == TARGET_LITTLE_ENDIAN)
                *val = data[0] | data[bank->bus_width] << 8;
        else
                *val = data[bank->bus_width - 1] | data[(2 * bank->bus_width) - 1] << 8;
@@ -266,7 +269,7 @@ static int cfi_query_u32(struct flash_bank *bank, int sector, uint32_t offset, u
                        return retval;
        }
 
-       if (bank->target->endianness == TARGET_LITTLE_ENDIAN)
+       if (cfi_info->endianness == TARGET_LITTLE_ENDIAN)
                *val = data[0] | data[bank->bus_width] << 8 |
                        data[bank->bus_width * 2] << 16 | data[bank->bus_width * 3] << 24;
        else
@@ -803,6 +806,7 @@ static int cfi_intel_info(struct flash_bank *bank, char *buf, int buf_size)
 FLASH_BANK_COMMAND_HANDLER(cfi_flash_bank_command)
 {
        struct cfi_flash_bank *cfi_info;
+       int bus_swap = 0;
 
        if (CMD_ARGC < 6)
                return ERROR_COMMAND_SYNTAX_ERROR;
@@ -836,10 +840,19 @@ FLASH_BANK_COMMAND_HANDLER(cfi_flash_bank_command)
        for (unsigned i = 6; i < CMD_ARGC; i++) {
                if (strcmp(CMD_ARGV[i], "x16_as_x8") == 0)
                        cfi_info->x16_as_x8 = 1;
+               else if (strcmp(CMD_ARGV[i], "bus_swap") == 0)
+                       bus_swap = 1;
                else if (strcmp(CMD_ARGV[i], "jedec_probe") == 0)
                        cfi_info->jedec_probe = 1;
        }
 
+       if (bus_swap)
+               cfi_info->endianness =
+                       bank->target->endianness == TARGET_LITTLE_ENDIAN ?
+                       TARGET_BIG_ENDIAN : TARGET_LITTLE_ENDIAN;
+       else
+               cfi_info->endianness = bank->target->endianness;
+
        /* bank wasn't probed yet */
        cfi_info->qry[0] = 0xff;
 

diff --git a/src/flash/nor/cfi.h b/src/flash/nor/cfi.h
index d92fcc0b1d85bf211d8fa003fbccb581c9629159..5bd25e97241294831208c66dec19246a01f7e155 100644 (file)
--- a/src/flash/nor/cfi.h
+++ b/src/flash/nor/cfi.h
@@ -30,6 +30,8 @@ struct cfi_flash_bank {
        int not_cfi;
        int probed;
 
+       enum target_endianness endianness;
+
        uint16_t manufacturer;
        uint16_t device_id;