4 files changed, 222 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
index dab7847fc800..61c5ec850f2f 100644
--- a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
+++ b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
@@ -26,6 +26,9 @@ file systems on embedded devices.
  - linux,mtd-name: allow to specify the mtd name for retro capability with
    physmap-flash drivers as boot loader pass the mtd partition via the old
    device name physmap-flash.
+ - use-advanced-sector-protection: boolean to enable support for the
+   advanced sector protection (Spansion: PPB - Persistent Protection
+   Bits) locking.
 
 For JEDEC compatible devices, the following additional properties
 are defined:
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index b86197286f24..fff665d59a0d 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -33,6 +33,8 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/reboot.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/mtd/map.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/cfi.h>
@@ -74,6 +76,10 @@ static void put_chip(struct map_info *map, struct flchip *chip, unsigned long ad
 static int cfi_atmel_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 
+static int cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+static int cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+static int cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+
 static struct mtd_chip_driver cfi_amdstd_chipdrv = {
         .probe          = NULL, /* Not usable directly */
         .destroy        = cfi_amdstd_destroy,
@@ -496,6 +502,7 @@ static void cfi_fixup_m29ew_delay_after_resume(struct cfi_private *cfi)
 struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
 {
         struct cfi_private *cfi = map->fldrv_priv;
+        struct device_node __maybe_unused *np = map->device_node;
         struct mtd_info *mtd;
         int i;
 
@@ -570,6 +577,17 @@ struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
                         cfi_tell_features(extp);
 #endif
 
+#ifdef CONFIG_OF
+                        if (np && of_property_read_bool(
+                                    np, "use-advanced-sector-protection")
+                            && extp->BlkProtUnprot == 8) {
+                                printk(KERN_INFO "  Advanced Sector Protection (PPB Locking) supported\n");
+                                mtd->_lock = cfi_ppb_lock;
+                                mtd->_unlock = cfi_ppb_unlock;
+                                mtd->_is_locked = cfi_ppb_is_locked;
+                        }
+#endif
+
                         bootloc = extp->TopBottom;
                         if ((bootloc < 2) || (bootloc > 5)) {
                                 printk(KERN_WARNING "%s: CFI contains unrecognised boot "
@@ -2172,6 +2190,205 @@ static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
         return cfi_varsize_frob(mtd, do_atmel_unlock, ofs, len, NULL);
 }
 
+/*
+ * Advanced Sector Protection - PPB (Persistent Protection Bit) locking
+ */
+
+struct ppb_lock {
+        struct flchip *chip;
+        loff_t offset;
+        int locked;
+};
+
+#define MAX_SECTORS                     512
+
+#define DO_XXLOCK_ONEBLOCK_LOCK         ((void *)1)
+#define DO_XXLOCK_ONEBLOCK_UNLOCK       ((void *)2)
+#define DO_XXLOCK_ONEBLOCK_GETLOCK      ((void *)3)
+
+static int __maybe_unused do_ppb_xxlock(struct map_info *map,
+                                        struct flchip *chip,
+                                        unsigned long adr, int len, void *thunk)
+{
+        struct cfi_private *cfi = map->fldrv_priv;
+        unsigned long timeo;
+        int ret;
+
+        mutex_lock(&chip->mutex);
+        ret = get_chip(map, chip, adr + chip->start, FL_LOCKING);
+        if (ret) {
+                mutex_unlock(&chip->mutex);
+                return ret;
+        }
+
+        pr_debug("MTD %s(): XXLOCK 0x%08lx len %d\n", __func__, adr, len);
+
+        cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+                         cfi->device_type, NULL);
+        cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+                         cfi->device_type, NULL);
+        /* PPB entry command */
+        cfi_send_gen_cmd(0xC0, cfi->addr_unlock1, chip->start, map, cfi,
+                         cfi->device_type, NULL);
+
+        if (thunk == DO_XXLOCK_ONEBLOCK_LOCK) {
+                chip->state = FL_LOCKING;
+                map_write(map, CMD(0xA0), chip->start + adr);
+                map_write(map, CMD(0x00), chip->start + adr);
+        } else if (thunk == DO_XXLOCK_ONEBLOCK_UNLOCK) {
+                /*
+                 * Unlocking of one specific sector is not supported, so we
+                 * have to unlock all sectors of this device instead
+                 */
+                chip->state = FL_UNLOCKING;
+                map_write(map, CMD(0x80), chip->start);
+                map_write(map, CMD(0x30), chip->start);
+        } else if (thunk == DO_XXLOCK_ONEBLOCK_GETLOCK) {
+                chip->state = FL_JEDEC_QUERY;
+                /* Return locked status: 0->locked, 1->unlocked */
+                ret = !cfi_read_query(map, adr);
+        } else
+                BUG();
+
+        /*
+         * Wait for some time as unlocking of all sectors takes quite long
+         */
+        timeo = jiffies + msecs_to_jiffies(2000);       /* 2s max (un)locking */
+        for (;;) {
+                if (chip_ready(map, adr))
+                        break;
+
+                if (time_after(jiffies, timeo)) {
+                        printk(KERN_ERR "Waiting for chip to be ready timed out.\n");
+                        ret = -EIO;
+                        break;
+                }
+
+                UDELAY(map, chip, adr, 1);
+        }
+
+        /* Exit BC commands */
+        map_write(map, CMD(0x90), chip->start);
+        map_write(map, CMD(0x00), chip->start);
+
+        chip->state = FL_READY;
+        put_chip(map, chip, adr + chip->start);
+        mutex_unlock(&chip->mutex);
+
+        return ret;
+}
+
+static int __maybe_unused cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs,
+                                       uint64_t len)
+{
+        return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
+                                DO_XXLOCK_ONEBLOCK_LOCK);
+}
+
+static int __maybe_unused cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs,
+                                         uint64_t len)
+{
+        struct mtd_erase_region_info *regions = mtd->eraseregions;
+        struct map_info *map = mtd->priv;
+        struct cfi_private *cfi = map->fldrv_priv;
+        struct ppb_lock *sect;
+        unsigned long adr;
+        loff_t offset;
+        uint64_t length;
+        int chipnum;
+        int i;
+        int sectors;
+        int ret;
+
+        /*
+         * PPB unlocking always unlocks all sectors of the flash chip.
+         * We need to re-lock all previously locked sectors. So lets
+         * first check the locking status of all sectors and save
+         * it for future use.
+         */
+        sect = kzalloc(MAX_SECTORS * sizeof(struct ppb_lock), GFP_KERNEL);
+        if (!sect)
+                return -ENOMEM;
+
+        /*
+         * This code to walk all sectors is a slightly modified version
+         * of the cfi_varsize_frob() code.
+         */
+        i = 0;
+        chipnum = 0;
+        adr = 0;
+        sectors = 0;
+        offset = 0;
+        length = mtd->size;
+
+        while (length) {
+                int size = regions[i].erasesize;
+
+                /*
+                 * Only test sectors that shall not be unlocked. The other
+                 * sectors shall be unlocked, so lets keep their locking
+                 * status at "unlocked" (locked=0) for the final re-locking.
+                 */
+                if ((adr < ofs) || (adr >= (ofs + len))) {
+                        sect[sectors].chip = &cfi->chips[chipnum];
+                        sect[sectors].offset = offset;
+                        sect[sectors].locked = do_ppb_xxlock(
+                                map, &cfi->chips[chipnum], adr, 0,
+                                DO_XXLOCK_ONEBLOCK_GETLOCK);
+                }
+
+                adr += size;
+                offset += size;
+                length -= size;
+
+                if (offset == regions[i].offset + size * regions[i].numblocks)
+                        i++;
+
+                if (adr >> cfi->chipshift) {
+                        adr = 0;
+                        chipnum++;
+
+                        if (chipnum >= cfi->numchips)
+                                break;
+                }
+
+                sectors++;
+                if (sectors >= MAX_SECTORS) {
+                        printk(KERN_ERR "Only %d sectors for PPB locking supported!\n",
+                               MAX_SECTORS);
+                        kfree(sect);
+                        return -EINVAL;
+                }
+        }
+
+        /* Now unlock the whole chip */
+        ret = cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
+                               DO_XXLOCK_ONEBLOCK_UNLOCK);
+        if (ret) {
+                kfree(sect);
+                return ret;
+        }
+
+        /*
+         * PPB unlocking always unlocks all sectors of the flash chip.
+         * We need to re-lock all previously locked sectors.
+         */
+        for (i = 0; i < sectors; i++) {
+                if (sect[i].locked)
+                        do_ppb_xxlock(map, sect[i].chip, sect[i].offset, 0,
+                                      DO_XXLOCK_ONEBLOCK_LOCK);
+        }
+
+        kfree(sect);
+        return ret;
+}
+
+static int __maybe_unused cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs,
+                                            uint64_t len)
+{
+        return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
+                                DO_XXLOCK_ONEBLOCK_GETLOCK) ? 1 : 0;
+}
 
 static void cfi_amdstd_sync (struct mtd_info *mtd)
 {
diff --git a/drivers/mtd/maps/physmap_of.c b/drivers/mtd/maps/physmap_of.c
index 67cc73c18ddd..263d9e1b8001 100644
--- a/drivers/mtd/maps/physmap_of.c
+++ b/drivers/mtd/maps/physmap_of.c
@@ -241,6 +241,7 @@ static int of_flash_probe(struct platform_device *dev)
                 info->list[i].map.phys = res.start;
                 info->list[i].map.size = res_size;
                 info->list[i].map.bankwidth = be32_to_cpup(width);
+                info->list[i].map.device_node = dp;
 
                 err = -ENOMEM;
                 info->list[i].map.virt = ioremap(info->list[i].map.phys,
diff --git a/include/linux/mtd/map.h b/include/linux/mtd/map.h
index f6eb4332ac92..8b9bfd7dcaa3 100644
--- a/include/linux/mtd/map.h
+++ b/include/linux/mtd/map.h
@@ -245,6 +245,7 @@ struct map_info {
         unsigned long pfow_base;
         unsigned long map_priv_1;
         unsigned long map_priv_2;
+        struct device_node *device_node;
         void *fldrv_priv;
         struct mtd_chip_driver *fldrv;
 };