NOR: invalidate cached state on target resume
[fw/openocd] / src / flash / nor / core.c
index c2ea134a393609371be6bfb915476481db8cd24f..fc020a8a815c5ed4bc585ff098573197498197cc 100644 (file)
 #include <target/image.h>
 
 
+/**
+ * @file
+ * Upper level of NOR flash framework.
+ * The lower level interfaces are to drivers.  These upper level ones
+ * primarily support access from Tcl scripts or from GDB.
+ */
+
 struct flash_bank *flash_banks;
 
 int flash_driver_erase(struct flash_bank *bank, int first, int last)
@@ -279,11 +286,27 @@ int default_flash_blank_check(struct flash_bank *bank)
 
        return ERROR_OK;
 }
-/* erase given flash region, selects proper bank according to target and address */
-static int flash_iterate_address_range(struct target *target, uint32_t addr, uint32_t length,
+
+/* 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,
+               char *pad_reason, uint32_t addr, uint32_t length,
                int (*callback)(struct flash_bank *bank, int first, int last))
 {
        struct flash_bank *c;
+       uint32_t last_addr = addr + length;     /* first address AFTER end */
        int first = -1;
        int last = -1;
        int i;
@@ -301,37 +324,105 @@ static int flash_iterate_address_range(struct target *target, uint32_t addr, uin
        {
                /* special case, erase whole bank when length is zero */
                if (addr != c->base)
+               {
+                       LOG_ERROR("Whole bank access must start at beginning of bank.");
                        return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
+               }
 
                return callback(c, 0, c->num_sectors - 1);
        }
 
-       /* check whether it fits */
+       /* check whether it all fits in this bank */
        if (addr + length - 1 > c->base + c->size - 1)
+       {
+               LOG_ERROR("Flash access does not fit into bank.");
                return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
+       }
+
+       /** @todo: handle erasures that cross into adjacent banks */
 
        addr -= c->base;
+       last_addr -= c->base;
 
        for (i = 0; i < c->num_sectors; i++)
        {
-               /* check whether sector overlaps with the given range and is not yet erased */
-               if (addr < c->sectors[i].offset + c->sectors[i].size && addr + length > c->sectors[i].offset && c->sectors[i].is_erased != 1) {
-                       /* if first is not set yet then this is the first sector */
-                       if (first == -1)
+               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;
-                       last = i; /* and it is the last one so far in any case */
+
+                       /* 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 == 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;
+               }
+
+               /* MUST finish on a sector boundary */
+               if (last_addr <= f->offset)
+                       break;
        }
 
-       if (first == -1 || last == -1)
-               return ERROR_OK;
+       /* invalid start or end address? */
+       if (first == -1 || last == -1) {
+               LOG_ERROR("address range 0x%8.8x .. 0x%8.8x "
+                               "is not sector-aligned",
+                               (unsigned) (c->base + addr),
+                               (unsigned) (c->base + last_addr - 1));
+               return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
+       }
 
+       /* 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)
+int flash_erase_address_range(struct target *target,
+               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);
 }
 
@@ -342,7 +433,11 @@ 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);
 }
 
@@ -356,6 +451,12 @@ 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;
 
@@ -371,7 +472,7 @@ int flash_write_unlock(struct target *target, struct image *image,
        }
 
        /* allocate padding array */
-       padding = malloc(image->num_sections * sizeof(padding));
+       padding = calloc(image->num_sections, sizeof(*padding));
 
        /* loop until we reach end of the image */
        while (section < image->num_sections)
@@ -409,10 +510,31 @@ int flash_write_unlock(struct target *target, struct image *image,
                {
                        if (image->sections[section_last + 1].base_address < (run_address + run_size))
                        {
-                               LOG_DEBUG("section %d out of order(very slightly surprising, but supported)", section_last + 1);
+                               LOG_DEBUG("section %d out of order "
+                                               "(surprising, but supported)",
+                                               section_last + 1);
+                               /* REVISIT this can break with autoerase ...
+                                * clobbering data after it's written.
+                                */
                                break;
                        }
-                       /* if we have multiple sections within our image, flash programming could fail due to alignment issues
+
+                       /* FIXME This needlessly touches sectors BETWEEN the
+                        * sections it's writing.  Without auto erase, it just
+                        * writes ones.  That WILL INVALIDATE data in cases
+                        * like Stellaris Tempest chips, corrupting internal
+                        * ECC codes; and at least FreeScale suggests issues
+                        * with that approach (in HC11 documentation).
+                        *
+                        * With auto erase enabled, data in those sectors will
+                        * be needlessly destroyed; and some of the limited
+                        * number of flash erase cycles will be wasted...
+                        *
+                        * 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
                         * 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))
@@ -420,7 +542,6 @@ int flash_write_unlock(struct target *target, struct image *image,
                        padding[section_last] = pad_bytes;
                        run_size += image->sections[++section_last].size;
                        run_size += pad_bytes;
-                       padding[section_last] = 0;
 
                        LOG_INFO("Padding image section %d with %d bytes", section_last-1, pad_bytes);
                }
@@ -428,11 +549,35 @@ int flash_write_unlock(struct target *target, struct image *image,
                /* fit the run into bank constraints */
                if (run_address + run_size - 1 > c->base + c->size - 1)
                {
+                       /* REVISIT isn't this superfluous, given the while()
+                        * loop conditions above??
+                        */
                        LOG_WARNING("writing %d bytes only - as image section is %d bytes and bank is only %d bytes", \
                                    (int)(c->base + c->size - run_address), (int)(run_size), (int)(c->size));
                        run_size = c->base + c->size - run_address;
                }
 
+               /* If we're applying any sector automagic, then pad this
+                * (maybe-combined) segment to the end of its last sector.
+                */
+               if (unlock || erase) {
+                       int sector;
+                       uint32_t offset_start = run_address - c->base;
+                       uint32_t offset_end = offset_start + run_size;
+                       uint32_t end = offset_end, delta;
+
+                       for (sector = 0; sector < c->num_sectors; sector++) {
+                               end = c->sectors[sector].offset
+                                               + c->sectors[sector].size;
+                               if (offset_end <= end)
+                                       break;
+                       }
+
+                       delta = end - offset_end;
+                       padding[section_last] += delta;
+                       run_size += delta;
+               }
+
                /* allocate buffer */
                buffer = malloc(run_size);
                buffer_size = 0;
@@ -479,7 +624,8 @@ 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);
                        }
                }
 
@@ -511,3 +657,34 @@ int flash_write(struct target *target, struct image *image,
 {
        return flash_write_unlock(target, image, written, erase, false);
 }
+
+/**
+ * Invalidates cached flash state which a target can change as it runs.
+ *
+ * @param target The target being resumed
+ *
+ * OpenOCD caches some flash state for brief periods.  For example, a sector
+ * that is protected must be unprotected before OpenOCD tries to write it,
+ * Also, a sector that's not erased must be erased before it's written.
+ *
+ * As a rule, OpenOCD and target firmware can both modify the flash, so when
+ * a target starts running, OpenOCD needs to invalidate its cached state.
+ */
+void nor_resume(struct target *target)
+{
+       struct flash_bank *bank;
+
+       for (bank = flash_banks; bank; bank = bank->next) {
+               int i;
+
+               if (bank->target != target)
+                       continue;
+
+               for (i = 0; i < bank->num_sectors; i++) {
+                       struct flash_sector *sector = bank->sectors + i;
+
+                       sector->is_erased = -1;
+                       sector->is_protected = -1;
+               }
+       }
+}