257 lines
7.4 KiB
C
257 lines
7.4 KiB
C
|
/*
|
||
|
|
* MTD map driver for BIOS Flash on Intel SCB2 boards
|
||
|
|
* Copyright (C) 2002 Sun Microsystems, Inc.
|
||
|
|
* Tim Hockin <thockin@sun.com>
|
||
|
|
*
|
||
|
|
* A few notes on this MTD map:
|
||
|
|
*
|
||
|
|
* This was developed with a small number of SCB2 boards to test on.
|
||
|
|
* Hopefully, Intel has not introducted too many unaccounted variables in the
|
||
|
|
* making of this board.
|
||
|
|
*
|
||
|
|
* The BIOS marks its own memory region as 'reserved' in the e820 map. We
|
||
|
|
* try to request it here, but if it fails, we carry on anyway.
|
||
|
|
*
|
||
|
|
* This is how the chip is attached, so said the schematic:
|
||
|
|
* * a 4 MiB (32 Mib) 16 bit chip
|
||
|
|
* * a 1 MiB memory region
|
||
|
|
* * A20 and A21 pulled up
|
||
|
|
* * D8-D15 ignored
|
||
|
|
* What this means is that, while we are addressing bytes linearly, we are
|
||
|
|
* really addressing words, and discarding the other byte. This means that
|
||
|
|
* the chip MUST BE at least 2 MiB. This also means that every block is
|
||
|
|
* actually half as big as the chip reports. It also means that accesses of
|
||
|
|
* logical address 0 hit higher-address sections of the chip, not physical 0.
|
||
|
|
* One can only hope that these 4MiB x16 chips were a lot cheaper than 1MiB x8
|
||
|
|
* chips.
|
||
|
|
*
|
||
|
|
* This driver assumes the chip is not write-protected by an external signal.
|
||
|
|
* As of the this writing, that is true, but may change, just to spite me.
|
||
|
|
*
|
||
|
|
* The actual BIOS layout has been mostly reverse engineered. Intel BIOS
|
||
|
|
* updates for this board include 10 related (*.bio - &.bi9) binary files and
|
||
|
|
* another separate (*.bbo) binary file. The 10 files are 64k of data + a
|
||
|
|
* small header. If the headers are stripped off, the 10 64k files can be
|
||
|
|
* concatenated into a 640k image. This is your BIOS image, proper. The
|
||
|
|
* separate .bbo file also has a small header. It is the 'Boot Block'
|
||
|
|
* recovery BIOS. Once the header is stripped, no further prep is needed.
|
||
|
|
* As best I can tell, the BIOS is arranged as such:
|
||
|
|
* offset 0x00000 to 0x4ffff (320k): unknown - SCSI BIOS, etc?
|
||
|
|
* offset 0x50000 to 0xeffff (640k): BIOS proper
|
||
|
|
* offset 0xf0000 ty 0xfffff (64k): Boot Block region
|
||
|
|
*
|
||
|
|
* Intel's BIOS update program flashes the BIOS and Boot Block in separate
|
||
|
|
* steps. Probably a wise thing to do.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/types.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/pci.h>
|
||
|
|
#include <linux/pci_ids.h>
|
||
|
|
|
||
|
|
#define MODNAME "scb2_flash"
|
||
|
|
#define SCB2_ADDR 0xfff00000
|
||
|
|
#define SCB2_WINDOW 0x00100000
|
||
|
|
|
||
|
|
|
||
|
|
static void __iomem *scb2_ioaddr;
|
||
|
|
static struct mtd_info *scb2_mtd;
|
||
|
|
static struct map_info scb2_map = {
|
||
|
|
.name = "SCB2 BIOS Flash",
|
||
|
|
.size = 0,
|
||
|
|
.bankwidth = 1,
|
||
|
|
};
|
||
|
|
static int region_fail;
|
||
|
|
|
||
|
|
static int __devinit
|
||
|
|
scb2_fixup_mtd(struct mtd_info *mtd)
|
||
|
|
{
|
||
|
|
int i;
|
||
|
|
int done = 0;
|
||
|
|
struct map_info *map = mtd->priv;
|
||
|
|
struct cfi_private *cfi = map->fldrv_priv;
|
||
|
|
|
||
|
|
/* barf if this doesn't look right */
|
||
|
|
if (cfi->cfiq->InterfaceDesc != CFI_INTERFACE_X16_ASYNC) {
|
||
|
|
printk(KERN_ERR MODNAME ": unsupported InterfaceDesc: %#x\n",
|
||
|
|
cfi->cfiq->InterfaceDesc);
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* I wasn't here. I didn't see. dwmw2. */
|
||
|
|
|
||
|
|
/* the chip is sometimes bigger than the map - what a waste */
|
||
|
|
mtd->size = map->size;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* We only REALLY get half the chip, due to the way it is
|
||
|
|
* wired up - D8-D15 are tossed away. We read linear bytes,
|
||
|
|
* but in reality we are getting 1/2 of each 16-bit read,
|
||
|
|
* which LOOKS linear to us. Because CFI code accounts for
|
||
|
|
* things like lock/unlock/erase by eraseregions, we need to
|
||
|
|
* fudge them to reflect this. Erases go like this:
|
||
|
|
* * send an erase to an address
|
||
|
|
* * the chip samples the address and erases the block
|
||
|
|
* * add the block erasesize to the address and repeat
|
||
|
|
* -- the problem is that addresses are 16-bit addressable
|
||
|
|
* -- we end up erasing every-other block
|
||
|
|
*/
|
||
|
|
mtd->erasesize /= 2;
|
||
|
|
for (i = 0; i < mtd->numeraseregions; i++) {
|
||
|
|
struct mtd_erase_region_info *region = &mtd->eraseregions[i];
|
||
|
|
region->erasesize /= 2;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* If the chip is bigger than the map, it is wired with the high
|
||
|
|
* address lines pulled up. This makes us access the top portion of
|
||
|
|
* the chip, so all our erase-region info is wrong. Start cutting from
|
||
|
|
* the bottom.
|
||
|
|
*/
|
||
|
|
for (i = 0; !done && i < mtd->numeraseregions; i++) {
|
||
|
|
struct mtd_erase_region_info *region = &mtd->eraseregions[i];
|
||
|
|
|
||
|
|
if (region->numblocks * region->erasesize > mtd->size) {
|
||
|
|
region->numblocks = ((unsigned long)mtd->size /
|
||
|
|
region->erasesize);
|
||
|
|
done = 1;
|
||
|
|
} else {
|
||
|
|
region->numblocks = 0;
|
||
|
|
}
|
||
|
|
region->offset = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* CSB5's 'Function Control Register' has bits for decoding @ >= 0xffc00000 */
|
||
|
|
#define CSB5_FCR 0x41
|
||
|
|
#define CSB5_FCR_DECODE_ALL 0x0e
|
||
|
|
static int __devinit
|
||
|
|
scb2_flash_probe(struct pci_dev *dev, const struct pci_device_id *ent)
|
||
|
|
{
|
||
|
|
u8 reg;
|
||
|
|
|
||
|
|
/* enable decoding of the flash region in the south bridge */
|
||
|
|
pci_read_config_byte(dev, CSB5_FCR, ®);
|
||
|
|
pci_write_config_byte(dev, CSB5_FCR, reg | CSB5_FCR_DECODE_ALL);
|
||
|
|
|
||
|
|
if (!request_mem_region(SCB2_ADDR, SCB2_WINDOW, scb2_map.name)) {
|
||
|
|
/*
|
||
|
|
* The BIOS seems to mark the flash region as 'reserved'
|
||
|
|
* in the e820 map. Warn and go about our business.
|
||
|
|
*/
|
||
|
|
printk(KERN_WARNING MODNAME
|
||
|
|
": warning - can't reserve rom window, continuing\n");
|
||
|
|
region_fail = 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* remap the IO window (w/o caching) */
|
||
|
|
scb2_ioaddr = ioremap_nocache(SCB2_ADDR, SCB2_WINDOW);
|
||
|
|
if (!scb2_ioaddr) {
|
||
|
|
printk(KERN_ERR MODNAME ": Failed to ioremap window!\n");
|
||
|
|
if (!region_fail)
|
||
|
|
release_mem_region(SCB2_ADDR, SCB2_WINDOW);
|
||
|
|
return -ENOMEM;
|
||
|
|
}
|
||
|
|
|
||
|
|
scb2_map.phys = SCB2_ADDR;
|
||
|
|
scb2_map.virt = scb2_ioaddr;
|
||
|
|
scb2_map.size = SCB2_WINDOW;
|
||
|
|
|
||
|
|
simple_map_init(&scb2_map);
|
||
|
|
|
||
|
|
/* try to find a chip */
|
||
|
|
scb2_mtd = do_map_probe("cfi_probe", &scb2_map);
|
||
|
|
|
||
|
|
if (!scb2_mtd) {
|
||
|
|
printk(KERN_ERR MODNAME ": flash probe failed!\n");
|
||
|
|
iounmap(scb2_ioaddr);
|
||
|
|
if (!region_fail)
|
||
|
|
release_mem_region(SCB2_ADDR, SCB2_WINDOW);
|
||
|
|
return -ENODEV;
|
||
|
|
}
|
||
|
|
|
||
|
|
scb2_mtd->owner = THIS_MODULE;
|
||
|
|
if (scb2_fixup_mtd(scb2_mtd) < 0) {
|
||
|
|
del_mtd_device(scb2_mtd);
|
||
|
|
map_destroy(scb2_mtd);
|
||
|
|
iounmap(scb2_ioaddr);
|
||
|
|
if (!region_fail)
|
||
|
|
release_mem_region(SCB2_ADDR, SCB2_WINDOW);
|
||
|
|
return -ENODEV;
|
||
|
|
}
|
||
|
|
|
||
|
|
printk(KERN_NOTICE MODNAME ": chip size 0x%llx at offset 0x%llx\n",
|
||
|
|
(unsigned long long)scb2_mtd->size,
|
||
|
|
(unsigned long long)(SCB2_WINDOW - scb2_mtd->size));
|
||
|
|
|
||
|
|
add_mtd_device(scb2_mtd);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __devexit
|
||
|
|
scb2_flash_remove(struct pci_dev *dev)
|
||
|
|
{
|
||
|
|
if (!scb2_mtd)
|
||
|
|
return;
|
||
|
|
|
||
|
|
/* disable flash writes */
|
||
|
|
if (scb2_mtd->lock)
|
||
|
|
scb2_mtd->lock(scb2_mtd, 0, scb2_mtd->size);
|
||
|
|
|
||
|
|
del_mtd_device(scb2_mtd);
|
||
|
|
map_destroy(scb2_mtd);
|
||
|
|
|
||
|
|
iounmap(scb2_ioaddr);
|
||
|
|
scb2_ioaddr = NULL;
|
||
|
|
|
||
|
|
if (!region_fail)
|
||
|
|
release_mem_region(SCB2_ADDR, SCB2_WINDOW);
|
||
|
|
pci_set_drvdata(dev, NULL);
|
||
|
|
}
|
||
|
|
|
||
|
|
static struct pci_device_id scb2_flash_pci_ids[] = {
|
||
|
|
{
|
||
|
|
.vendor = PCI_VENDOR_ID_SERVERWORKS,
|
||
|
|
.device = PCI_DEVICE_ID_SERVERWORKS_CSB5,
|
||
|
|
.subvendor = PCI_ANY_ID,
|
||
|
|
.subdevice = PCI_ANY_ID
|
||
|
|
},
|
||
|
|
{ 0, }
|
||
|
|
};
|
||
|
|
|
||
|
|
static struct pci_driver scb2_flash_driver = {
|
||
|
|
.name = "Intel SCB2 BIOS Flash",
|
||
|
|
.id_table = scb2_flash_pci_ids,
|
||
|
|
.probe = scb2_flash_probe,
|
||
|
|
.remove = __devexit_p(scb2_flash_remove),
|
||
|
|
};
|
||
|
|
|
||
|
|
static int __init
|
||
|
|
scb2_flash_init(void)
|
||
|
|
{
|
||
|
|
return pci_register_driver(&scb2_flash_driver);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void __exit
|
||
|
|
scb2_flash_exit(void)
|
||
|
|
{
|
||
|
|
pci_unregister_driver(&scb2_flash_driver);
|
||
|
|
}
|
||
|
|
|
||
|
|
module_init(scb2_flash_init);
|
||
|
|
module_exit(scb2_flash_exit);
|
||
|
|
|
||
|
|
MODULE_LICENSE("GPL");
|
||
|
|
MODULE_AUTHOR("Tim Hockin <thockin@sun.com>");
|
||
|
|
MODULE_DESCRIPTION("MTD map driver for Intel SCB2 BIOS Flash");
|
||
|
|
MODULE_DEVICE_TABLE(pci, scb2_flash_pci_ids);
|