flash: use stm32f2x flash size register

Use the flash size register to calculate flash info.

Change-Id: Ia230db8a08d440710c030a9e5001f20561c9f420
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Reviewed-on: http://openocd.zylin.com/337
Tested-by: jenkins
Reviewed-by: Mathias Küster <kesmtp@freenet.de>

diff --git a/src/flash/nor/stm32f2x.c b/src/flash/nor/stm32f2x.c
index ec5527bcdf136ca844d1f1ff6011c29be97da65d..1fca3eba42251572eee9e3bbb5d399d2b64684c0 100644 (file)
--- a/src/flash/nor/stm32f2x.c
+++ b/src/flash/nor/stm32f2x.c
@@ -575,7 +575,7 @@ static int stm32x_probe(struct flash_bank *bank)
        struct target *target = bank->target;
        struct stm32x_flash_bank *stm32x_info = bank->driver_priv;
        int i;
-       uint16_t num_pages;
+       uint16_t flash_size_in_kb;
        uint32_t device_id;
        uint32_t base_address = 0x08000000;
 
@@ -587,22 +587,38 @@ static int stm32x_probe(struct flash_bank *bank)
                return retval;
        LOG_INFO("device id = 0x%08" PRIx32 "", device_id);
 
-       if ((device_id & 0x7ff) != 0x411)
-       {
-               LOG_WARNING("Cannot identify target as a STM32 family, try the other STM32 drivers.");
+       /* get flash size from target. */
+       retval = target_read_u16(target, 0x1FFF7A10, &flash_size_in_kb);
+       if (retval != ERROR_OK) {
+               LOG_WARNING("failed reading flash size, default to max target family");
+               /* failed reading flash size, default to max target family */
+               flash_size_in_kb = 0xffff;
+       }
+
+       if ((device_id & 0x7ff) == 0x411) {
+               /* check for early silicon */
+               if (flash_size_in_kb == 0xffff) {
+                       /* number of sectors may be incorrrect on early silicon */
+                       LOG_WARNING("STM32 flash size failed, probe inaccurate - assuming 512k flash");
+                       flash_size_in_kb = 512;
+               }
+       } else {
+               LOG_WARNING("Cannot identify target as a STM32 family.");
                return ERROR_FAIL;
        }
 
-       /* sectors sizes vary, handle this in a different code path
-        * than the rest.
-        */
-       // Uhhh.... what to use here?
+       LOG_INFO("flash size = %dkbytes", flash_size_in_kb);
 
-       /* calculate numbers of pages*/
-       num_pages = 4 + 1 + 7;
+       /* did we assign flash size? */
+       assert(flash_size_in_kb != 0xffff);
 
-       if (bank->sectors)
-       {
+       /* calculate numbers of pages */
+       int num_pages = (flash_size_in_kb / 128) + 4;
+
+       /* check that calculation result makes sense */
+       assert(num_pages > 0);
+
+       if (bank->sectors) {
                free(bank->sectors);
                bank->sectors = NULL;
        }
@@ -610,20 +626,20 @@ static int stm32x_probe(struct flash_bank *bank)
        bank->base = base_address;
        bank->num_sectors = num_pages;
        bank->sectors = malloc(sizeof(struct flash_sector) * num_pages);
-
        bank->size = 0;
+
+       /* fixed memory */
        setup_sector(bank, 0, 4, 16 * 1024);
        setup_sector(bank, 4, 1, 64 * 1024);
-       setup_sector(bank, 4+1, 7, 128 * 1024);
 
-       for (i = 0; i < num_pages; i++)
-       {
+       /* dynamic memory */
+       setup_sector(bank, 4 + 1, num_pages - 5, 128 * 1024);
+
+       for (i = 0; i < num_pages; i++) {
                bank->sectors[i].is_erased = -1;
                bank->sectors[i].is_protected = 0;
        }
 
-       LOG_INFO("flash size = %dkBytes", bank->size / 1024);
-
        stm32x_info->probed = 1;
 
        return ERROR_OK;