Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm...

[karo-tx-linux.git] / drivers / mtd / bcm47xxpart.c

diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
index 63feb75cc8e01d2048949343955023b01fc7fadc..9279a9174f84ad9cd3a2ae2c7117c29cc8134e9e 100644 (file)
--- a/drivers/mtd/bcm47xxpart.c
+++ b/drivers/mtd/bcm47xxpart.c
@@ -19,6 +19,12 @@
 /* 10 parts were found on sflash on Netgear WNDR4500 */
 #define BCM47XXPART_MAX_PARTS          12
 
+/*
+ * Amount of bytes we read when analyzing each block of flash memory.
+ * Set it big enough to allow detecting partition and reading important data.
+ */
+#define BCM47XXPART_BYTES_TO_READ      0x404
+
 /* Magics */
 #define BOARD_DATA_MAGIC               0x5246504D      /* MPFR */
 #define POT_MAGIC1                     0x54544f50      /* POTT */
@@ -57,17 +63,15 @@ static int bcm47xxpart_parse(struct mtd_info *master,
        struct trx_header *trx;
        int trx_part = -1;
        int last_trx_part = -1;
-       int max_bytes_to_read = 0x8004;
+       int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, };
 
        if (blocksize <= 0x10000)
                blocksize = 0x10000;
-       if (blocksize == 0x20000)
-               max_bytes_to_read = 0x18004;
 
        /* Alloc */
        parts = kzalloc(sizeof(struct mtd_partition) * BCM47XXPART_MAX_PARTS,
                        GFP_KERNEL);
-       buf = kzalloc(max_bytes_to_read, GFP_KERNEL);
+       buf = kzalloc(BCM47XXPART_BYTES_TO_READ, GFP_KERNEL);
 
        /* Parse block by block looking for magics */
        for (offset = 0; offset <= master->size - blocksize;
@@ -82,7 +86,7 @@ static int bcm47xxpart_parse(struct mtd_info *master,
                }
 
                /* Read beginning of the block */
-               if (mtd_read(master, offset, max_bytes_to_read,
+               if (mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
                             &bytes_read, (uint8_t *)buf) < 0) {
                        pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
                               offset);
@@ -96,20 +100,6 @@ static int bcm47xxpart_parse(struct mtd_info *master,
                        continue;
                }
 
-               /* Standard NVRAM */
-               if (buf[0x000 / 4] == NVRAM_HEADER ||
-                   buf[0x1000 / 4] == NVRAM_HEADER ||
-                   buf[0x8000 / 4] == NVRAM_HEADER ||
-                   (blocksize == 0x20000 && (
-                     buf[0x10000 / 4] == NVRAM_HEADER ||
-                     buf[0x11000 / 4] == NVRAM_HEADER ||
-                     buf[0x18000 / 4] == NVRAM_HEADER))) {
-                       bcm47xxpart_add_part(&parts[curr_part++], "nvram",
-                                            offset, 0);
-                       offset = rounddown(offset, blocksize);
-                       continue;
-               }
-
                /*
                 * board_data starts with board_id which differs across boards,
                 * but we can use 'MPFR' (hopefully) magic at 0x100
@@ -178,6 +168,30 @@ static int bcm47xxpart_parse(struct mtd_info *master,
                        continue;
                }
        }
+
+       /* Look for NVRAM at the end of the last block. */
+       for (i = 0; i < ARRAY_SIZE(possible_nvram_sizes); i++) {
+               if (curr_part > BCM47XXPART_MAX_PARTS) {
+                       pr_warn("Reached maximum number of partitions, scanning stopped!\n");
+                       break;
+               }
+
+               offset = master->size - possible_nvram_sizes[i];
+               if (mtd_read(master, offset, 0x4, &bytes_read,
+                            (uint8_t *)buf) < 0) {
+                       pr_err("mtd_read error while reading at offset 0x%X!\n",
+                              offset);
+                       continue;
+               }
+
+               /* Standard NVRAM */
+               if (buf[0] == NVRAM_HEADER) {
+                       bcm47xxpart_add_part(&parts[curr_part++], "nvram",
+                                            master->size - blocksize, 0);
+                       break;
+               }
+       }
+
        kfree(buf);
 
        /*