jtag: jtag_add_ir_scan() now takes a single field

[openocd.git] / src / flash / nor / core.c

diff --git a/src/flash/nor/core.c b/src/flash/nor/core.c
index fc020a8a815c5ed4bc585ff098573197498197cc..767006d27e10003190b7cf4b1a4df20661c76126 100644 (file)
--- a/src/flash/nor/core.c
+++ b/src/flash/nor/core.c
@@ -54,6 +54,63 @@ int flash_driver_erase(struct flash_bank *bank, int first, int last)
 int flash_driver_protect(struct flash_bank *bank, int set, int first, int last)
 {
        int retval;
+       bool updated = false;
+
+       /* NOTE: "first == last" means protect just that sector */
+
+       /* callers may not supply illegal parameters ... */
+       if (first < 0 || first > last || last >= bank->num_sectors)
+               return ERROR_FAIL;
+
+       /* force "set" to 0/1 */
+       set = !!set;
+
+       /*
+        * Filter out what trivial nonsense we can, so drivers don't have to.
+        *
+        * Don't tell drivers to change to the current state...  it's needless,
+        * and reducing the amount of work to be done (potentially to nothing)
+        * speeds at least some things up.
+        */
+scan:
+       for (int i = first; i < last; i++) {
+               struct flash_sector *sector = bank->sectors + i;
+
+               /* Only filter requests to protect the already-protected, or
+                * to unprotect the already-unprotected.  Changing from the
+                * unknown state (-1) to a known one is unwise but allowed;
+                * protection status is best checked first.
+                */
+               if (sector->is_protected != set)
+                       continue;
+
+               /* Shrink this range of sectors from the start; don't overrun
+                * the end.  Also shrink from the end; don't overun the start.
+                *
+                * REVISIT we could handle discontiguous regions by issuing
+                * more than one driver request.  How much would that matter?
+                */
+               if (i == first) {
+                       updated = true;
+                       first++;
+               } else if (i == last) {
+                       updated = true;
+                       last--;
+               }
+       }
+
+       /* updating the range affects the tests in the scan loop above; so
+        * re-scan, to make sure we didn't miss anything.
+        */
+       if (updated) {
+               updated = false;
+               goto scan;
+       }
+
+       /* Single sector, already protected?  Nothing to do! */
+       if (first == last)
+               return ERROR_OK;
+
 
        retval = bank->driver->protect(bank, set, first, last);
        if (retval != ERROR_OK)