[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>

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

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

drivers/mtd/maps/esb2rom.c

+/*
+ * 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");