nand: adjust erase/read/write partition/chip size for bad blocks

Adjust the sizes calculated for whole partition/chip operations by
removing the size of bad blocks so we don't try to erase/read/write
past a partition/chip boundary.

Signed-off-by: Harvey Chapman <hchapman@3gfp.com>

diff --git a/common/cmd_nand.c b/common/cmd_nand.c
index e9d3d3c..f20223c 100644 (file)
--- a/common/cmd_nand.c
+++ b/common/cmd_nand.c
@@ -425,6 +425,31 @@ static int raw_access(nand_info_t *nand, ulong addr, loff_t off, ulong count,
        return ret;
 }
 
+/* Adjust a chip/partition size down for bad blocks so we don't
+ * read/write/erase past the end of a chip/partition by accident.
+ */
+static void adjust_size_for_badblocks(loff_t *size, loff_t offset, int dev)
+{
+       /* We grab the nand info object here fresh because this is usually
+        * called after arg_off_size() which can change the value of dev.
+        */
+       nand_info_t *nand = &nand_info[dev];
+       loff_t maxoffset = offset + *size;
+       int badblocks = 0;
+
+       /* count badblocks in NAND from offset to offset + size */
+       for (; offset < maxoffset; offset += nand->erasesize) {
+               if (nand_block_isbad(nand, offset))
+                       badblocks++;
+       }
+       /* adjust size if any bad blocks found */
+       if (badblocks) {
+               *size -= badblocks * nand->erasesize;
+               printf("size adjusted to 0x%llx (%d bad blocks)\n",
+                      (unsigned long long)*size, badblocks);
+       }
+}
+
 static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
        int i, ret = 0;
@@ -521,6 +546,7 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
                int scrub = !strncmp(cmd, "scrub", 5);
                int spread = 0;
                int args = 2;
+               int adjust_size = 0;
                const char *scrub_warn =
                        "Warning: "
                        "scrub option will erase all factory set bad blocks!\n"
@@ -537,8 +563,10 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
                                spread = 1;
                        } else if (!strcmp(&cmd[5], ".part")) {
                                args = 1;
+                               adjust_size = 1;
                        } else if (!strcmp(&cmd[5], ".chip")) {
                                args = 0;
+                               adjust_size = 1;
                        } else {
                                goto usage;
                        }
@@ -558,6 +586,10 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
                                 &maxsize) != 0)
                        return 1;
 
+               /* size is unspecified */
+               if (adjust_size && !scrub)
+                       adjust_size_for_badblocks(&size, off, dev);
+
                nand = &nand_info[dev];
 
                memset(&opts, 0, sizeof(opts));
@@ -642,6 +674,9 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
                                                &off, &size, &maxsize) != 0)
                                return 1;
 
+                       /* size is unspecified */
+                       if (argc < 5)
+                               adjust_size_for_badblocks(&size, off, dev);
                        rwsize = size;
                }