1 files changed, 217 insertions, 128 deletions

diff --git a/drivers/mtd/maps/physmap_of.c b/drivers/mtd/maps/physmap_of.c
index fbd613968717..aeed9ea79714 100644
--- a/drivers/mtd/maps/physmap_of.c
+++ b/drivers/mtd/maps/physmap_of.c
@@ -1,9 +1,12 @@
 /*
- * Normal mappings of chips in physical memory for OF devices
+ * Flash mappings described by the OF (or flattened) device tree
  *
  * Copyright (C) 2006 MontaVista Software Inc.
  * Author: Vitaly Wool <vwool@ru.mvista.com>
  *
+ * Revised to handle newer style flash binding by:
+ *   Copyright (C) 2007 David Gibson, IBM Corporation.
+ *
  * This program is free software; you can redistribute  it and/or modify it
  * under  the terms of  the GNU General  Public License as published by the
  * Free Software Foundation;  either version 2 of the  License, or (at your
@@ -12,102 +15,157 @@
 
 #include <linux/module.h>
 #include <linux/types.h>
-#include <linux/kernel.h>
 #include <linux/init.h>
-#include <linux/slab.h>
 #include <linux/device.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/map.h>
 #include <linux/mtd/partitions.h>
-#include <linux/mtd/physmap.h>
-#include <asm/io.h>
-#include <asm/prom.h>
-#include <asm/of_device.h>
-#include <asm/of_platform.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 
-struct physmap_flash_info {
+struct of_flash {
         struct mtd_info         *mtd;
         struct map_info         map;
         struct resource         *res;
 #ifdef CONFIG_MTD_PARTITIONS
-        int                     nr_parts;
         struct mtd_partition    *parts;
 #endif
 };
 
-static const char *rom_probe_types[] = { "cfi_probe", "jedec_probe", "map_rom", NULL };
 #ifdef CONFIG_MTD_PARTITIONS
-static const char *part_probe_types[] = { "cmdlinepart", "RedBoot", NULL };
-#endif
+#define OF_FLASH_PARTS(info)    ((info)->parts)
 
-#ifdef CONFIG_MTD_PARTITIONS
-static int parse_flash_partitions(struct device_node *node,
-                struct mtd_partition **parts)
+static int parse_obsolete_partitions(struct of_device *dev,
+                                     struct of_flash *info,
+                                     struct device_node *dp)
 {
-        int i, plen, retval = -ENOMEM;
-        const  u32  *part;
-        const  char *name;
-
-        part = of_get_property(node, "partitions", &plen);
-        if (part == NULL)
-                goto err;
-
-        retval = plen / (2 * sizeof(u32));
-        *parts = kzalloc(retval * sizeof(struct mtd_partition), GFP_KERNEL);
-        if (*parts == NULL) {
-                printk(KERN_ERR "Can't allocate the flash partition data!\n");
-                goto err;
-        }
+        int i, plen, nr_parts;
+        const struct {
+                u32 offset, len;
+        } *part;
+        const char *names;
+
+        part = of_get_property(dp, "partitions", &plen);
+        if (!part)
+                return 0; /* No partitions found */
+
+        dev_warn(&dev->dev, "Device tree uses obsolete partition map binding\n");
+
+        nr_parts = plen / sizeof(part[0]);
+
+        info->parts = kzalloc(nr_parts * sizeof(*info->parts), GFP_KERNEL);
+        if (!info->parts)
+                return -ENOMEM;
 
-        name = of_get_property(node, "partition-names", &plen);
+        names = of_get_property(dp, "partition-names", &plen);
 
-        for (i = 0; i < retval; i++) {
-                (*parts)[i].offset = *part++;
-                (*parts)[i].size   = *part & ~1;
-                if (*part++ & 1) /* bit 0 set signifies read only partition */
-                        (*parts)[i].mask_flags = MTD_WRITEABLE;
+        for (i = 0; i < nr_parts; i++) {
+                info->parts[i].offset = part->offset;
+                info->parts[i].size   = part->len & ~1;
+                if (part->len & 1) /* bit 0 set signifies read only partition */
+                        info->parts[i].mask_flags = MTD_WRITEABLE;
 
-                if (name != NULL && plen > 0) {
-                        int len = strlen(name) + 1;
+                if (names && (plen > 0)) {
+                        int len = strlen(names) + 1;
 
-                        (*parts)[i].name = (char *)name;
+                        info->parts[i].name = (char *)names;
                         plen -= len;
-                        name += len;
-                } else
-                        (*parts)[i].name = "unnamed";
+                        names += len;
+                } else {
+                        info->parts[i].name = "unnamed";
+                }
+
+                part++;
         }
-err:
-        return retval;
+
+        return nr_parts;
 }
-#endif
 
-static int of_physmap_remove(struct of_device *dev)
+static int __devinit parse_partitions(struct of_flash *info,
+                                      struct of_device *dev)
+{
+        const char *partname;
+        static const char *part_probe_types[]
+                = { "cmdlinepart", "RedBoot", NULL };
+        struct device_node *dp = dev->node, *pp;
+        int nr_parts, i;
+
+        /* First look for RedBoot table or partitions on the command
+         * line, these take precedence over device tree information */
+        nr_parts = parse_mtd_partitions(info->mtd, part_probe_types,
+                                        &info->parts, 0);
+        if (nr_parts > 0) {
+                add_mtd_partitions(info->mtd, info->parts, nr_parts);
+                return 0;
+        }
+
+        /* First count the subnodes */
+        nr_parts = 0;
+        for (pp = dp->child; pp; pp = pp->sibling)
+                nr_parts++;
+
+        if (nr_parts == 0)
+                return parse_obsolete_partitions(dev, info, dp);
+
+        info->parts = kzalloc(nr_parts * sizeof(*info->parts),
+                              GFP_KERNEL);
+        if (!info->parts)
+                return -ENOMEM;
+
+        for (pp = dp->child, i = 0; pp; pp = pp->sibling, i++) {
+                const u32 *reg;
+                int len;
+
+                reg = of_get_property(pp, "reg", &len);
+                if (!reg || (len != 2*sizeof(u32))) {
+                        dev_err(&dev->dev, "Invalid 'reg' on %s\n",
+                                dp->full_name);
+                        kfree(info->parts);
+                        info->parts = NULL;
+                        return -EINVAL;
+                }
+                info->parts[i].offset = reg[0];
+                info->parts[i].size = reg[1];
+
+                partname = of_get_property(pp, "label", &len);
+                if (!partname)
+                        partname = of_get_property(pp, "name", &len);
+                info->parts[i].name = (char *)partname;
+
+                if (of_get_property(pp, "read-only", &len))
+                        info->parts[i].mask_flags = MTD_WRITEABLE;
+        }
+
+        return nr_parts;
+}
+#else /* MTD_PARTITIONS */
+#define OF_FLASH_PARTS(info)            (0)
+#define parse_partitions(info, dev)     (0)
+#endif /* MTD_PARTITIONS */
+
+static int of_flash_remove(struct of_device *dev)
 {
-        struct physmap_flash_info *info;
+        struct of_flash *info;
 
         info = dev_get_drvdata(&dev->dev);
-        if (info == NULL)
+        if (!info)
                 return 0;
         dev_set_drvdata(&dev->dev, NULL);
 
-        if (info->mtd != NULL) {
-#ifdef CONFIG_MTD_PARTITIONS
-                if (info->nr_parts) {
+        if (info->mtd) {
+                if (OF_FLASH_PARTS(info)) {
                         del_mtd_partitions(info->mtd);
-                        kfree(info->parts);
+                        kfree(OF_FLASH_PARTS(info));
                 } else {
                         del_mtd_device(info->mtd);
                 }
-#else
-                del_mtd_device(info->mtd);
-#endif
                 map_destroy(info->mtd);
         }
 
-        if (info->map.virt != NULL)
+        if (info->map.virt)
                 iounmap(info->map.virt);
 
-        if (info->res != NULL) {
+        if (info->res) {
                 release_resource(info->res);
                 kfree(info->res);
         }
@@ -115,47 +173,78 @@ static int of_physmap_remove(struct of_device *dev)
         return 0;
 }
 
-static int __devinit of_physmap_probe(struct of_device *dev, const struct of_device_id *match)
+/* Helper function to handle probing of the obsolete "direct-mapped"
+ * compatible binding, which has an extra "probe-type" property
+ * describing the type of flash probe necessary. */
+static struct mtd_info * __devinit obsolete_probe(struct of_device *dev,
+                                                  struct map_info *map)
 {
         struct device_node *dp = dev->node;
-        struct resource res;
-        struct physmap_flash_info *info;
-        const char **probe_type;
         const char *of_probe;
+        struct mtd_info *mtd;
+        static const char *rom_probe_types[]
+                = { "cfi_probe", "jedec_probe", "map_rom"};
+        int i;
+
+        dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" "
+                 "flash binding\n");
+
+        of_probe = of_get_property(dp, "probe-type", NULL);
+        if (!of_probe) {
+                for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) {
+                        mtd = do_map_probe(rom_probe_types[i], map);
+                        if (mtd)
+                                return mtd;
+                }
+                return NULL;
+        } else if (strcmp(of_probe, "CFI") == 0) {
+                return do_map_probe("cfi_probe", map);
+        } else if (strcmp(of_probe, "JEDEC") == 0) {
+                return do_map_probe("jedec_probe", map);
+        } else {
+                if (strcmp(of_probe, "ROM") != 0)
+                        dev_warn(&dev->dev, "obsolete_probe: don't know probe "
+                                 "type '%s', mapping as rom\n", of_probe);
+                return do_map_probe("mtd_rom", map);
+        }
+}
+
+static int __devinit of_flash_probe(struct of_device *dev,
+                                    const struct of_device_id *match)
+{
+        struct device_node *dp = dev->node;
+        struct resource res;
+        struct of_flash *info;
+        const char *probe_type = match->data;
         const u32 *width;
         int err;
 
-
+        err = -ENXIO;
         if (of_address_to_resource(dp, 0, &res)) {
-                dev_err(&dev->dev, "Can't get the flash mapping!\n");
-                err = -EINVAL;
+                dev_err(&dev->dev, "Can't get IO address from device tree\n");
                 goto err_out;
         }
 
-        dev_dbg(&dev->dev, "physmap flash device: %.8llx at %.8llx\n",
-            (unsigned long long)res.end - res.start + 1,
-            (unsigned long long)res.start);
+        dev_dbg(&dev->dev, "of_flash device: %.8llx-%.8llx\n",
+                (unsigned long long)res.start, (unsigned long long)res.end);
 
-        info = kzalloc(sizeof(struct physmap_flash_info), GFP_KERNEL);
-        if (info == NULL) {
-                err = -ENOMEM;
+        err = -ENOMEM;
+        info = kzalloc(sizeof(*info), GFP_KERNEL);
+        if (!info)
                 goto err_out;
-        }
 
         dev_set_drvdata(&dev->dev, info);
 
+        err = -EBUSY;
         info->res = request_mem_region(res.start, res.end - res.start + 1,
-                        dev->dev.bus_id);
-        if (info->res == NULL) {
-                dev_err(&dev->dev, "Could not reserve memory region\n");
-                err = -ENOMEM;
+                                       dev->dev.bus_id);
+        if (!info->res)
                 goto err_out;
-        }
 
+        err = -ENXIO;
         width = of_get_property(dp, "bank-width", NULL);
-        if (width == NULL) {
-                dev_err(&dev->dev, "Can't get the flash bank width!\n");
-                err = -EINVAL;
+        if (!width) {
+                dev_err(&dev->dev, "Can't get bank width from device tree\n");
                 goto err_out;
         }
 
@@ -164,87 +253,87 @@ static int __devinit of_physmap_probe(struct of_device *dev, const struct of_dev
         info->map.size = res.end - res.start + 1;
         info->map.bankwidth = *width;
 
+        err = -ENOMEM;
         info->map.virt = ioremap(info->map.phys, info->map.size);
-        if (info->map.virt == NULL) {
-                dev_err(&dev->dev, "Failed to ioremap flash region\n");
-                err = EIO;
+        if (!info->map.virt) {
+                dev_err(&dev->dev, "Failed to ioremap() flash region\n");
                 goto err_out;
         }
 
         simple_map_init(&info->map);
 
-        of_probe = of_get_property(dp, "probe-type", NULL);
-        if (of_probe == NULL) {
-                probe_type = rom_probe_types;
-                for (; info->mtd == NULL && *probe_type != NULL; probe_type++)
-                        info->mtd = do_map_probe(*probe_type, &info->map);
-        } else if (!strcmp(of_probe, "CFI"))
-                info->mtd = do_map_probe("cfi_probe", &info->map);
-        else if (!strcmp(of_probe, "JEDEC"))
-                info->mtd = do_map_probe("jedec_probe", &info->map);
-        else {
-                if (strcmp(of_probe, "ROM"))
-                        dev_dbg(&dev->dev, "map_probe: don't know probe type "
-                        "'%s', mapping as rom\n", of_probe);
-                info->mtd = do_map_probe("mtd_rom", &info->map);
-        }
-        if (info->mtd == NULL) {
-                dev_err(&dev->dev, "map_probe failed\n");
-                err = -ENXIO;
+        if (probe_type)
+                info->mtd = do_map_probe(probe_type, &info->map);
+        else
+                info->mtd = obsolete_probe(dev, &info->map);
+
+        err = -ENXIO;
+        if (!info->mtd) {
+                dev_err(&dev->dev, "do_map_probe() failed\n");
                 goto err_out;
         }
         info->mtd->owner = THIS_MODULE;
 
-#ifdef CONFIG_MTD_PARTITIONS
-        err = parse_mtd_partitions(info->mtd, part_probe_types, &info->parts, 0);
-        if (err > 0) {
-                add_mtd_partitions(info->mtd, info->parts, err);
-        } else if ((err = parse_flash_partitions(dp, &info->parts)) > 0) {
-                dev_info(&dev->dev, "Using OF partition information\n");
-                add_mtd_partitions(info->mtd, info->parts, err);
-                info->nr_parts = err;
-        } else
-#endif
+        err = parse_partitions(info, dev);
+        if (err < 0)
+                goto err_out;
+
+        if (err > 0)
+                add_mtd_partitions(info->mtd, OF_FLASH_PARTS(info), err);
+        else
+                add_mtd_device(info->mtd);
 
-        add_mtd_device(info->mtd);
         return 0;
 
 err_out:
-        of_physmap_remove(dev);
+        of_flash_remove(dev);
         return err;
 }
 
-static struct of_device_id of_physmap_match[] = {
+static struct of_device_id of_flash_match[] = {
+        {
+                .compatible     = "cfi-flash",
+                .data           = (void *)"cfi_probe",
+        },
+        {
+                /* FIXME: JEDEC chips can't be safely and reliably
+                 * probed, although the mtd code gets it right in
+                 * practice most of the time.  We should use the
+                 * vendor and device ids specified by the binding to
+                 * bypass the heuristic probe code, but the mtd layer
+                 * provides, at present, no interface for doing so
+                 * :(. */
+                .compatible     = "jedec-flash",
+                .data           = (void *)"jedec_probe",
+        },
         {
                 .type           = "rom",
                 .compatible     = "direct-mapped"
         },
         { },
 };
+MODULE_DEVICE_TABLE(of, of_flash_match);
 
-MODULE_DEVICE_TABLE(of, of_physmap_match);
-
-
-static struct of_platform_driver of_physmap_flash_driver = {
-        .name           = "physmap-flash",
-        .match_table    = of_physmap_match,
-        .probe          = of_physmap_probe,
-        .remove         = of_physmap_remove,
+static struct of_platform_driver of_flash_driver = {
+        .name           = "of-flash",
+        .match_table    = of_flash_match,
+        .probe          = of_flash_probe,
+        .remove         = of_flash_remove,
 };
 
-static int __init of_physmap_init(void)
+static int __init of_flash_init(void)
 {
-        return of_register_platform_driver(&of_physmap_flash_driver);
+        return of_register_platform_driver(&of_flash_driver);
 }
 
-static void __exit of_physmap_exit(void)
+static void __exit of_flash_exit(void)
 {
-        of_unregister_platform_driver(&of_physmap_flash_driver);
+        of_unregister_platform_driver(&of_flash_driver);
 }
 
-module_init(of_physmap_init);
-module_exit(of_physmap_exit);
+module_init(of_flash_init);
+module_exit(of_flash_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
-MODULE_DESCRIPTION("Configurable MTD map driver for OF");
+MODULE_DESCRIPTION("Device tree based MTD map driver");