NOR: add optional "flash erase_address" sector padding
[fw/openocd] / src / flash / nor / core.c
index 9083ed15ef92a95dda02aa4f0d9362922c2b4905..aedaa8661c66ecfa69e4f4dcb69f9e254a63c9a3 100644 (file)
@@ -287,9 +287,22 @@ int default_flash_blank_check(struct flash_bank *bank)
        return ERROR_OK;
 }
 
-/* erase given flash region, selects proper bank according to target and address */
+/* Manipulate given flash region, selecting the bank according to target
+ * and address.  Maps an address range to a set of sectors, and issues
+ * the callback() on that set ... e.g. to erase or unprotect its members.
+ *
+ * (Note a current bad assumption:  that protection operates on the same
+ * size sectors as erase operations use.)
+ *
+ * The "pad_reason" parameter is a kind of boolean:  when it's NULL, the
+ * range must fit those sectors exactly.  This is clearly safe; it can't
+ * erase data which the caller said to leave alone, for example.  If it's
+ * non-NULL, rather than failing, extra data in the first and/or last
+ * sectors will be added to the range, and that reason string is used when
+ * warning about those additions.
+ */
 static int flash_iterate_address_range(struct target *target,
-               uint32_t addr, uint32_t length,
+               char *pad_reason, uint32_t addr, uint32_t length,
                int (*callback)(struct flash_bank *bank, int first, int last))
 {
        struct flash_bank *c;
@@ -328,18 +341,53 @@ static int flash_iterate_address_range(struct target *target,
        for (i = 0; i < c->num_sectors; i++)
        {
                struct flash_sector *f = c->sectors + i;
+               uint32_t end = f->offset + f->size;
 
                /* start only on a sector boundary */
                if (first < 0) {
+                       /* scanned past the first sector? */
+                       if (addr < f->offset)
+                               break;
+
                        /* is this the first sector? */
                        if (addr == f->offset)
                                first = i;
-                       else if (addr < f->offset)
-                               break;
+
+                       /* Does this need head-padding?  If so, pad and warn;
+                        * or else force an error.
+                        *
+                        * Such padding can make trouble, since *WE* can't
+                        * ever know if that data was in use.  The warning
+                        * should help users sort out messes later.
+                        */
+                       else if (addr < end && pad_reason) {
+                               /* FIXME say how many bytes (e.g. 80 KB) */
+                               LOG_WARNING("Adding extra %s range, "
+                                               "%#8.8x to %#8.8x",
+                                       pad_reason,
+                                       (unsigned) f->offset,
+                                       (unsigned) addr - 1);
+                               first = i;
+                       } else
+                               continue;
                }
 
                /* is this (also?) the last sector? */
-               if (last_addr == f->offset + f->size) {
+               if (last_addr == end) {
+                       last = i;
+                       break;
+               }
+
+               /* Does this need tail-padding?  If so, pad and warn;
+                * or else force an error.
+                */
+               if (last_addr < end && pad_reason) {
+                       /* FIXME say how many bytes (e.g. 80 KB) */
+                       LOG_WARNING("Adding extra %s range, "
+                                       "%#8.8x to %#8.8x",
+                               pad_reason,
+                               (unsigned) last_addr,
+                               (unsigned) end - 1);
                        last = i;
                        break;
                }
@@ -358,18 +406,17 @@ static int flash_iterate_address_range(struct target *target,
                return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
        }
 
-       /* The NOR driver may trim this range down, based on
-        * whether or not a given sector is already erased.
-        *
-        * REVISIT should *we* trim it... ?
+       /* The NOR driver may trim this range down, based on what
+        * sectors are already erased/unprotected.  GDB currently
+        * blocks such optimizations.
         */
        return callback(c, first, last);
 }
 
 int flash_erase_address_range(struct target *target,
-               uint32_t addr, uint32_t length)
+               bool pad, uint32_t addr, uint32_t length)
 {
-       return flash_iterate_address_range(target,
+       return flash_iterate_address_range(target, pad ? "erase" : NULL,
                        addr, length, &flash_driver_erase);
 }
 
@@ -380,7 +427,11 @@ static int flash_driver_unprotect(struct flash_bank *bank, int first, int last)
 
 static int flash_unlock_address_range(struct target *target, uint32_t addr, uint32_t length)
 {
-       return flash_iterate_address_range(target,
+       /* By default, pad to sector boundaries ... the real issue here
+        * is that our (only) caller *permanently* removes protection,
+        * and doesn't restore it.
+        */
+       return flash_iterate_address_range(target, "unprotect",
                        addr, length, &flash_driver_unprotect);
 }
 
@@ -394,6 +445,12 @@ int flash_write_unlock(struct target *target, struct image *image,
        struct flash_bank *c;
        int *padding;
 
+       /* REVISIT do_pad should perhaps just be another parameter.
+        * GDB wouldn't ever need it, since it erases separately.
+        * But "flash write_image" commands might want that option.
+        */
+       bool do_pad = false;
+
        section = 0;
        section_offset = 0;
 
@@ -470,7 +527,8 @@ int flash_write_unlock(struct target *target, struct image *image,
                         * In both cases, the extra writes slow things down.
                         */
 
-                       /* if we have multiple sections within our image, flash programming could fail due to alignment issues
+                       /* if we have multiple sections within our image,
+                        * flash programming could fail due to alignment issues
                         * attempt to rebuild a consecutive buffer for the flash loader */
                        pad_bytes = (image->sections[section_last + 1].base_address) - (run_address + run_size);
                        if ((run_address + run_size + pad_bytes) > (c->base + c->size))
@@ -560,7 +618,8 @@ int flash_write_unlock(struct target *target, struct image *image,
                        if (erase)
                        {
                                /* calculate and erase sectors */
-                               retval = flash_erase_address_range(target, run_address, run_size);
+                               retval = flash_erase_address_range(target,
+                                               do_pad, run_address, run_size);
                        }
                }