[MTD] MAPS: Support for BIOS flash chips on Intel ESB2 southbridge

Add MTD map driver for BIOS flash chips connected to the Intel ESB2
southbridge.

[akpm@osdl.org: coding-style fixes, build fix]
Signed-off-by: Ryan Jackson <rjackson@lnxi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

3 files changed, 459 insertions, 0 deletions

diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig
index 24747bdc3e19..7514a9bee015 100644
--- a/drivers/mtd/maps/Kconfig
+++ b/drivers/mtd/maps/Kconfig
@@ -184,6 +184,15 @@ config MTD_ICHXROM
 
           BE VERY CAREFUL.
 
+config MTD_ESB2ROM
+        tristate "BIOS flash chip on Intel ESB Controller Hub 2"
+        depends on X86 && MTD_JEDECPROBE
+        help
+          Support for treating the BIOS flash chip on ESB2 motherboards
+          as an MTD device - with this you can reprogram your BIOS.
+
+          BE VERY CAREFUL.
+
 config MTD_SCB2_FLASH
         tristate "BIOS flash chip on Intel SCB2 boards"
         depends on X86 && MTD_JEDECPROBE
diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile
index 191c1928bbec..9061432c5e1a 100644
--- a/drivers/mtd/maps/Makefile
+++ b/drivers/mtd/maps/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_MTD_DC21285)	+= dc21285.o
 obj-$(CONFIG_MTD_DILNETPC)      += dilnetpc.o
 obj-$(CONFIG_MTD_L440GX)        += l440gx.o
 obj-$(CONFIG_MTD_AMD76XROM)     += amd76xrom.o
+obj-$(CONFIG_MTD_ESB2ROM)       += esb2rom.o
 obj-$(CONFIG_MTD_ICHXROM)       += ichxrom.o
 obj-$(CONFIG_MTD_TSUNAMI)       += tsunami_flash.o
 obj-$(CONFIG_MTD_LUBBOCK)       += lubbock-flash.o
diff --git a/drivers/mtd/maps/esb2rom.c b/drivers/mtd/maps/esb2rom.c
new file mode 100644
index 000000000000..e1c781482bfa
--- /dev/null
+++ b/drivers/mtd/maps/esb2rom.c
@@ -0,0 +1,449 @@
+/*
+ * esb2rom.c
+ *
+ * Normal mappings of flash chips in physical memory
+ * through the Intel ESB2 Southbridge.
+ *
+ * This was derived from ichxrom.c in May 2006 by
+ *      Lew Glendenning <lglendenning@lnxi.com>
+ *
+ * Eric Biederman, of course, was a major help in this effort.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <asm/io.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/cfi.h>
+#include <linux/mtd/flashchip.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/list.h>
+
+#define MOD_NAME KBUILD_BASENAME
+
+#define ADDRESS_NAME_LEN 18
+
+#define ROM_PROBE_STEP_SIZE (64*1024) /* 64KiB */
+
+#define BIOS_CNTL       0xDC
+#define BIOS_LOCK_ENABLE        0x02
+#define BIOS_WRITE_ENABLE       0x01
+
+/* This became a 16-bit register, and EN2 has disappeared */
+#define FWH_DEC_EN1     0xD8
+#define FWH_F8_EN       0x8000
+#define FWH_F0_EN       0x4000
+#define FWH_E8_EN       0x2000
+#define FWH_E0_EN       0x1000
+#define FWH_D8_EN       0x0800
+#define FWH_D0_EN       0x0400
+#define FWH_C8_EN       0x0200
+#define FWH_C0_EN       0x0100
+#define FWH_LEGACY_F_EN 0x0080
+#define FWH_LEGACY_E_EN 0x0040
+/* reserved  0x0020 and 0x0010 */
+#define FWH_70_EN       0x0008
+#define FWH_60_EN       0x0004
+#define FWH_50_EN       0x0002
+#define FWH_40_EN       0x0001
+
+/* these are 32-bit values */
+#define FWH_SEL1        0xD0
+#define FWH_SEL2        0xD4
+
+#define FWH_8MiB        (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
+                         FWH_70_EN | FWH_60_EN | FWH_50_EN | FWH_40_EN)
+
+#define FWH_7MiB        (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
+                         FWH_70_EN | FWH_60_EN | FWH_50_EN)
+
+#define FWH_6MiB        (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
+                         FWH_70_EN | FWH_60_EN)
+
+#define FWH_5MiB        (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
+                         FWH_70_EN)
+
+#define FWH_4MiB        (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN)
+
+#define FWH_3_5MiB      (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN | FWH_D0_EN | FWH_C8_EN)
+
+#define FWH_3MiB        (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN | FWH_D0_EN)
+
+#define FWH_2_5MiB      (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
+                         FWH_D8_EN)
+
+#define FWH_2MiB        (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN)
+
+#define FWH_1_5MiB      (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN)
+
+#define FWH_1MiB        (FWH_F8_EN | FWH_F0_EN)
+
+#define FWH_0_5MiB      (FWH_F8_EN)
+
+
+struct esb2rom_window {
+        void __iomem* virt;
+        unsigned long phys;
+        unsigned long size;
+        struct list_head maps;
+        struct resource rsrc;
+        struct pci_dev *pdev;
+};
+
+struct esb2rom_map_info {
+        struct list_head list;
+        struct map_info map;
+        struct mtd_info *mtd;
+        struct resource rsrc;
+        char map_name[sizeof(MOD_NAME) + 2 + ADDRESS_NAME_LEN];
+};
+
+static struct esb2rom_window esb2rom_window = {
+        .maps = LIST_HEAD_INIT(esb2rom_window.maps),
+};
+
+static void esb2rom_cleanup(struct esb2rom_window *window)
+{
+        struct esb2rom_map_info *map, *scratch;
+        u8 byte;
+
+        /* Disable writes through the rom window */
+        pci_read_config_byte(window->pdev, BIOS_CNTL, &byte);
+        pci_write_config_byte(window->pdev, BIOS_CNTL,
+                byte & ~BIOS_WRITE_ENABLE);
+
+        /* Free all of the mtd devices */
+        list_for_each_entry_safe(map, scratch, &window->maps, list) {
+                if (map->rsrc.parent)
+                        release_resource(&map->rsrc);
+                del_mtd_device(map->mtd);
+                map_destroy(map->mtd);
+                list_del(&map->list);
+                kfree(map);
+        }
+        if (window->rsrc.parent)
+                release_resource(&window->rsrc);
+        if (window->virt) {
+                iounmap(window->virt);
+                window->virt = NULL;
+                window->phys = 0;
+                window->size = 0;
+                window->pdev = NULL;
+        }
+}
+
+static int __devinit esb2rom_init_one(struct pci_dev *pdev,
+                                const struct pci_device_id *ent)
+{
+        static char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
+        struct esb2rom_window *window = &esb2rom_window;
+        struct esb2rom_map_info *map = NULL;
+        unsigned long map_top;
+        u8 byte;
+        u16 word;
+
+        /* For now I just handle the ecb2 and I assume there
+         * are not a lot of resources up at the top of the address
+         * space.  It is possible to handle other devices in the
+         * top 16MiB but it is very painful.  Also since
+         * you can only really attach a FWH to an ICHX there
+         * a number of simplifications you can make.
+         *
+         * Also you can page firmware hubs if an 8MiB window isn't enough
+         * but don't currently handle that case either.
+         */
+        window->pdev = pdev;
+
+        /* RLG:  experiment 2.  Force the window registers to the widest values */
+
+/*
+        pci_read_config_word(pdev, FWH_DEC_EN1, &word);
+        printk(KERN_DEBUG "Original FWH_DEC_EN1 : %x\n", word);
+        pci_write_config_byte(pdev, FWH_DEC_EN1, 0xff);
+        pci_read_config_byte(pdev, FWH_DEC_EN1, &byte);
+        printk(KERN_DEBUG "New FWH_DEC_EN1 : %x\n", byte);
+
+        pci_read_config_byte(pdev, FWH_DEC_EN2, &byte);
+        printk(KERN_DEBUG "Original FWH_DEC_EN2 : %x\n", byte);
+        pci_write_config_byte(pdev, FWH_DEC_EN2, 0x0f);
+        pci_read_config_byte(pdev, FWH_DEC_EN2, &byte);
+        printk(KERN_DEBUG "New FWH_DEC_EN2 : %x\n", byte);
+*/
+
+        /* Find a region continuous to the end of the ROM window  */
+        window->phys = 0;
+        pci_read_config_word(pdev, FWH_DEC_EN1, &word);
+        printk(KERN_DEBUG "pci_read_config_byte : %x\n", word);
+
+        if ((word & FWH_8MiB) == FWH_8MiB)
+                window->phys = 0xff400000;
+        else if ((word & FWH_7MiB) == FWH_7MiB)
+                window->phys = 0xff500000;
+        else if ((word & FWH_6MiB) == FWH_6MiB)
+                window->phys = 0xff600000;
+        else if ((word & FWH_5MiB) == FWH_5MiB)
+                window->phys = 0xFF700000;
+        else if ((word & FWH_4MiB) == FWH_4MiB)
+                window->phys = 0xffc00000;
+        else if ((word & FWH_3_5MiB) == FWH_3_5MiB)
+                window->phys = 0xffc80000;
+        else if ((word & FWH_3MiB) == FWH_3MiB)
+                window->phys = 0xffd00000;
+        else if ((word & FWH_2_5MiB) == FWH_2_5MiB)
+                window->phys = 0xffd80000;
+        else if ((word & FWH_2MiB) == FWH_2MiB)
+                window->phys = 0xffe00000;
+        else if ((word & FWH_1_5MiB) == FWH_1_5MiB)
+                window->phys = 0xffe80000;
+        else if ((word & FWH_1MiB) == FWH_1MiB)
+                window->phys = 0xfff00000;
+        else if ((word & FWH_0_5MiB) == FWH_0_5MiB)
+                window->phys = 0xfff80000;
+
+        /* reserved  0x0020 and 0x0010 */
+        window->phys -= 0x400000UL;
+        window->size = (0xffffffffUL - window->phys) + 1UL;
+
+        /* Enable writes through the rom window */
+        pci_read_config_byte(pdev, BIOS_CNTL, &byte);
+        if (!(byte & BIOS_WRITE_ENABLE)  && (byte & (BIOS_LOCK_ENABLE))) {
+                /* The BIOS will generate an error if I enable
+                 * this device, so don't even try.
+                 */
+                printk(KERN_ERR MOD_NAME ": firmware access control, I can't enable writes\n");
+                goto out;
+        }
+        pci_write_config_byte(pdev, BIOS_CNTL, byte | BIOS_WRITE_ENABLE);
+
+        /*
+         * Try to reserve the window mem region.  If this fails then
+         * it is likely due to the window being "reseved" by the BIOS.
+         */
+        window->rsrc.name = MOD_NAME;
+        window->rsrc.start = window->phys;
+        window->rsrc.end   = window->phys + window->size - 1;
+        window->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+        if (request_resource(&iomem_resource, &window->rsrc)) {
+                window->rsrc.parent = NULL;
+                printk(KERN_DEBUG MOD_NAME
+                        ": %s(): Unable to register resource"
+                        " 0x%.08llx-0x%.08llx - kernel bug?\n",
+                        __func__,
+                        (unsigned long long)window->rsrc.start,
+                        (unsigned long long)window->rsrc.end);
+        }
+
+        /* Map the firmware hub into my address space. */
+        window->virt = ioremap_nocache(window->phys, window->size);
+        if (!window->virt) {
+                printk(KERN_ERR MOD_NAME ": ioremap(%08lx, %08lx) failed\n",
+                        window->phys, window->size);
+                goto out;
+        }
+
+        /* Get the first address to look for an rom chip at */
+        map_top = window->phys;
+        if ((window->phys & 0x3fffff) != 0) {
+                /* if not aligned on 4MiB, look 4MiB lower in address space */
+                map_top = window->phys + 0x400000;
+        }
+#if 1
+        /* The probe sequence run over the firmware hub lock
+         * registers sets them to 0x7 (no access).
+         * (Insane hardware design, but most copied Intel's.)
+         * ==> Probe at most the last 4M of the address space.
+         */
+        if (map_top < 0xffc00000)
+                map_top = 0xffc00000;
+#endif
+        /* Loop through and look for rom chips */
+        while ((map_top - 1) < 0xffffffffUL) {
+                struct cfi_private *cfi;
+                unsigned long offset;
+                int i;
+
+                if (!map)
+                        map = kmalloc(sizeof(*map), GFP_KERNEL);
+                if (!map) {
+                        printk(KERN_ERR MOD_NAME ": kmalloc failed");
+                        goto out;
+                }
+                memset(map, 0, sizeof(*map));
+                INIT_LIST_HEAD(&map->list);
+                map->map.name = map->map_name;
+                map->map.phys = map_top;
+                offset = map_top - window->phys;
+                map->map.virt = (void __iomem *)
+                        (((unsigned long)(window->virt)) + offset);
+                map->map.size = 0xffffffffUL - map_top + 1UL;
+                /* Set the name of the map to the address I am trying */
+                sprintf(map->map_name, "%s @%08lx",
+                        MOD_NAME, map->map.phys);
+
+                /* Firmware hubs only use vpp when being programmed
+                 * in a factory setting.  So in-place programming
+                 * needs to use a different method.
+                 */
+                for(map->map.bankwidth = 32; map->map.bankwidth;
+                        map->map.bankwidth >>= 1) {
+                        char **probe_type;
+                        /* Skip bankwidths that are not supported */
+                        if (!map_bankwidth_supported(map->map.bankwidth))
+                                continue;
+
+                        /* Setup the map methods */
+                        simple_map_init(&map->map);
+
+                        /* Try all of the probe methods */
+                        probe_type = rom_probe_types;
+                        for(; *probe_type; probe_type++) {
+                                map->mtd = do_map_probe(*probe_type, &map->map);
+                                if (map->mtd)
+                                        goto found;
+                        }
+                }
+                map_top += ROM_PROBE_STEP_SIZE;
+                continue;
+        found:
+                /* Trim the size if we are larger than the map */
+                if (map->mtd->size > map->map.size) {
+                        printk(KERN_WARNING MOD_NAME
+                                " rom(%u) larger than window(%lu). fixing...\n",
+                                map->mtd->size, map->map.size);
+                        map->mtd->size = map->map.size;
+                }
+                if (window->rsrc.parent) {
+                        /*
+                         * Registering the MTD device in iomem may not be possible
+                         * if there is a BIOS "reserved" and BUSY range.  If this
+                         * fails then continue anyway.
+                         */
+                        map->rsrc.name  = map->map_name;
+                        map->rsrc.start = map->map.phys;
+                        map->rsrc.end   = map->map.phys + map->mtd->size - 1;
+                        map->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+                        if (request_resource(&window->rsrc, &map->rsrc)) {
+                                printk(KERN_ERR MOD_NAME
+                                        ": cannot reserve MTD resource\n");
+                                map->rsrc.parent = NULL;
+                        }
+                }
+
+                /* Make the whole region visible in the map */
+                map->map.virt = window->virt;
+                map->map.phys = window->phys;
+                cfi = map->map.fldrv_priv;
+                for(i = 0; i < cfi->numchips; i++)
+                        cfi->chips[i].start += offset;
+
+                /* Now that the mtd devices is complete claim and export it */
+                map->mtd->owner = THIS_MODULE;
+                if (add_mtd_device(map->mtd)) {
+                        map_destroy(map->mtd);
+                        map->mtd = NULL;
+                        goto out;
+                }
+
+                /* Calculate the new value of map_top */
+                map_top += map->mtd->size;
+
+                /* File away the map structure */
+                list_add(&map->list, &window->maps);
+                map = NULL;
+        }
+
+ out:
+        /* Free any left over map structures */
+        kfree(map);
+
+        /* See if I have any map structures */
+        if (list_empty(&window->maps)) {
+                esb2rom_cleanup(window);
+                return -ENODEV;
+        }
+        return 0;
+}
+
+static void __devexit esb2rom_remove_one (struct pci_dev *pdev)
+{
+        struct esb2rom_window *window = &esb2rom_window;
+        esb2rom_cleanup(window);
+}
+
+static struct pci_device_id esb2rom_pci_tbl[] __devinitdata = {
+        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_0,
+          PCI_ANY_ID, PCI_ANY_ID, },
+        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_0,
+          PCI_ANY_ID, PCI_ANY_ID, },
+        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
+          PCI_ANY_ID, PCI_ANY_ID, },
+        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_0,
+          PCI_ANY_ID, PCI_ANY_ID, },
+        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_1,
+          PCI_ANY_ID, PCI_ANY_ID, },
+        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_0,
+          PCI_ANY_ID, PCI_ANY_ID, },
+        { 0, },
+};
+
+#if 0
+MODULE_DEVICE_TABLE(pci, esb2rom_pci_tbl);
+
+static struct pci_driver esb2rom_driver = {
+        .name =         MOD_NAME,
+        .id_table =     esb2rom_pci_tbl,
+        .probe =        esb2rom_init_one,
+        .remove =       esb2rom_remove_one,
+};
+#endif
+
+static int __init init_esb2rom(void)
+{
+        struct pci_dev *pdev;
+        struct pci_device_id *id;
+        int retVal;
+
+        pdev = NULL;
+        for (id = esb2rom_pci_tbl; id->vendor; id++) {
+                printk(KERN_DEBUG "device id = %x\n", id->device);
+                pdev = pci_find_device(id->vendor, id->device, NULL);
+                if (pdev) {
+                        printk(KERN_DEBUG "matched device = %x\n", id->device);
+                        break;
+                }
+        }
+        if (pdev) {
+                printk(KERN_DEBUG "matched device id %x\n", id->device);
+                retVal = esb2rom_init_one(pdev, &esb2rom_pci_tbl[0]);
+                printk(KERN_DEBUG "retVal = %d\n", retVal);
+                return retVal;
+        }
+        return -ENXIO;
+#if 0
+        return pci_register_driver(&esb2rom_driver);
+#endif
+}
+
+static void __exit cleanup_esb2rom(void)
+{
+        esb2rom_remove_one(esb2rom_window.pdev);
+}
+
+module_init(init_esb2rom);
+module_exit(cleanup_esb2rom);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Lew Glendenning <lglendenning@lnxi.com>");
+MODULE_DESCRIPTION("MTD map driver for BIOS chips on the ESB2 southbridge");