[PATCH] [PATCH] [MTD] MAPS: Support for BIOS flash chips on the nvidia ck804 southbridge

Ryan Jackson
2006-10-24T17:47:54Z

From: Dave Olsen <dolsen@lnxi.com>

Add support for accessing BIOS flash chips connected to the NVIDIA ck804 southbridge.

Signed-off-by: Ryan Jackson <rjackson@lnxi.com>
---
drivers/mtd/maps/Kconfig | 9 +
drivers/mtd/maps/Makefile | 1
drivers/mtd/maps/ck804xrom.c | 353 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 363 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig
index 7514a9b..fa74668 100644
--- a/drivers/mtd/maps/Kconfig
+++ b/drivers/mtd/maps/Kconfig
@@ -193,6 +193,15 @@ config MTD_ESB2ROM

BE VERY CAREFUL.

+config MTD_CK804XROM
+ tristate "BIOS flash chip on Nvidia CK804"
+ depends on X86 && MTD_JEDECPROBE
+ help
+ Support for treating the BIOS flash chip on nvidia 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 9061432..3450521 100644
--- a/drivers/mtd/maps/Makefile
+++ b/drivers/mtd/maps/Makefile
@@ -19,6 +19,7 @@ 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-$(CONFIG_MTD_CK804XROM) += ck804xrom.o
obj-$(CONFIG_MTD_TSUNAMI) += tsunami_flash.o
obj-$(CONFIG_MTD_LUBBOCK) += lubbock-flash.o
obj-$(CONFIG_MTD_MAINSTONE) += mainstone-flash.o
diff --git a/drivers/mtd/maps/ck804xrom.c b/drivers/mtd/maps/ck804xrom.c
new file mode 100644
index 0000000..def2f2e
--- /dev/null
+++ b/drivers/mtd/maps/ck804xrom.c
@@ -0,0 +1,353 @@
+/*
+ * ck804xrom.c
+ *
+ * Normal mappings of chips in physical memory
+ * $Id: ck804xrom.c,v 1.1 2005/01/06 16:58:24 dolsen Exp $
+ */
+
+#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/config.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 */
+
+struct ck804xrom_window {
+ void __iomem *virt;
+ unsigned long phys;
+ unsigned long size;
+ struct list_head maps;
+ struct resource rsrc;
+ struct pci_dev *pdev;
+};
+
+struct ck804xrom_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];
+};
+
+
+/* The 2 bits controlling the window size are often set to allow reading
+ * the BIOS, but too small to allow writing, since the lock registers are
+ * 4MB lower in the address space than the data.
+ *
+ * This is intended to prevent flashing the bios, perhaps accidentally.
+ *
+ * This parameter allows the normal driver to over-ride the BIOS settings.
+ *
+ * The bits are 6 and 7. If both bits are set, it is a 5MB window.
+ * If only the 7 Bit is set, it is a 4MB window. Otherwise, a
+ * 64KB window.
+ *
+ */
+static uint win_size_bits = 0;
+module_param(win_size_bits, uint, 0);
+MODULE_PARM_DESC(win_size_bits, "ROM window size bits override for 0x43 byte, normally set by BIOS.");
+
+static struct ck804xrom_window ck804xrom_window = {
+ .maps = LIST_HEAD_INIT(ck804xrom_window.maps),
+};
+
+static void ck804xrom_cleanup(struct ck804xrom_window *window)
+{
+ struct ck804xrom_map_info *map, *scratch;
+ u8 byte;
+
+ if (window->pdev) {
+ /* Disable writes through the rom window */
+ pci_read_config_byte(window->pdev, 0x6d, &byte);
+ pci_write_config_byte(window->pdev, 0x6d, byte & ~1);
+ }
+
+ /* 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;
+ }
+ pci_dev_put(window->pdev);
+}
+
+
+static int __devinit ck804xrom_init_one (struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ static char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
+ u8 byte;
+ struct ck804xrom_window *window = &ck804xrom_window;
+ struct ck804xrom_map_info *map = 0;
+ unsigned long map_top;
+
+ /* Remember the pci dev I find the window in */
+ window->pdev = pci_dev_get(pdev);
+
+ /* Enable the selected rom window. This is often incorrectly
+ * set up by the BIOS, and the 4MB offset for the lock registers
+ * requires the full 5MB of window space.
+ *
+ * This 'write, then read' approach leaves the bits for
+ * other uses of the hardware info.
+ */
+ pci_read_config_byte(pdev, 0x88, &byte);
+ pci_write_config_byte(pdev, 0x88, byte | win_size_bits );
+
+
+ /* Assume the rom window is properly setup, and find it's size */
+ pci_read_config_byte(pdev, 0x88, &byte);
+
+ if ((byte & ((1<<7)|(1<<6))) == ((1<<7)|(1<<6))) {
+ window->phys = 0xffb00000; /* 5MiB */
+ }
+ else if ((byte & (1<<7)) == (1<<7)) {
+ window->phys = 0xffb00000; /* 4MiB */
+ /* open up the register space */
+ pci_write_config_byte(pdev, 0x88, byte | (1<<6));
+ }
+ else {
+ window->phys = 0xffff0000; /* 64KiB */
+ }
+ window->size = 0xffffffffUL - window->phys + 1UL;
+
+ /*
+ * Try to reserve the window mem region. If this fails then
+ * it is likely due to a fragment of the window being
+ * "reserved" by the BIOS. In the case that the
+ * request_mem_region() fails then once the rom size is
+ * discovered we will try to reserve the unreserved fragment.
+ */
+ 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_ERR 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);
+ }
+
+ /* Enable writes through the rom window */
+ pci_read_config_byte(pdev, 0x6d, &byte);
+ pci_write_config_byte(pdev, 0x6d, byte | 1);
+
+ /* FIXME handle registers 0x80 - 0x8C the bios region locks */
+
+ /* For write accesses caches are useless */
+ window->virt = ioremap_nocache(window->phys, window->size);
+ if (!window->virt) {
+ printk(KERN_ERR MOD_NAME ": Failed to ioremap\n");
+ goto out;
+ }
+
+ /* Get the first address to look for an rom chip at */
+ map_top = window->phys;
+#if 1
+ /* The probe sequence run over the firmware hub lock
+ * registers sets them to 0x7 (no access).
+ * 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);
+
+ /* There is no generic VPP support */
+ 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;
+ add_mtd_device(map->mtd);
+
+
+ /* Calculate the new value of map_top */
+ map_top += map->mtd->size;
+
+ /* File away the map structure */
+ list_add(&map->list, &window->maps);
+ map = 0;
+ }
+
+ out:
+ /* Free any left over map structures */
+ if (map) {
+ kfree(map);
+ }
+ /* See if I have any map structures */
+ if (list_empty(&window->maps)) {
+ ck804xrom_cleanup(window);
+ return -ENODEV;
+ }
+ return 0;
+}
+
+
+static void __devexit ck804xrom_remove_one (struct pci_dev *pdev)
+{
+ struct ck804xrom_window *window = &ck804xrom_window;
+
+ ck804xrom_cleanup(window);
+}
+
+static struct pci_device_id ck804xrom_pci_tbl[] = {
+ { PCI_VENDOR_ID_NVIDIA, 0x0051,
+ PCI_ANY_ID, PCI_ANY_ID, }, /* nvidia ck804 */
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, ck804xrom_pci_tbl);
+
+#if 0
+static struct pci_driver ck804xrom_driver = {
+ .name = MOD_NAME,
+ .id_table = ck804xrom_pci_tbl,
+ .probe = ck804xrom_init_one,
+ .remove = ck804xrom_remove_one,
+};
+#endif
+
+int __init init_ck804xrom(void)
+{
+ struct pci_dev *pdev;
+ struct pci_device_id *id;
+ int retVal;
+ pdev = NULL;
+
+ for(id = ck804xrom_pci_tbl; id->vendor; id++) {
+ pdev = pci_get_device(id->vendor, id->device, NULL);
+ if (pdev) {
+ break;
+ }
+ }
+ if (pdev) {
+ retVal = ck804xrom_init_one(pdev, &ck804xrom_pci_tbl[0]);
+ pci_dev_put(pdev);
+ return retVal;
+ }
+ return -ENXIO;
+#if 0
+ return pci_module_init(&ck804xrom_driver);
+#endif
+}
+
+static void __exit cleanup_ck804xrom(void)
+{
+ ck804xrom_remove_one(ck804xrom_window.pdev);
+}
+
+module_init(init_ck804xrom);
+module_exit(cleanup_ck804xrom);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Eric Biederman <ebiederman@lnxi.com>, Dave Olsen <dolsen@lnxi.com>");
+MODULE_DESCRIPTION("MTD map driver for BIOS chips on the Nvidia ck804 southbridge");
+
--
1.4.2.3