linux/drivers/mtd/maps/l440gx.c
Paul Parsons 5fbabf3f45 mtd: maps: l440gx: Add reference counter to set_vpp()
This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch allows l440gx_set_vpp() calls to be nested by adding a reference
counter.

Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:52:49 +01:00

166 lines
4 KiB
C

/*
* BIOS Flash chip on Intel 440GX board.
*
* Bugs this currently does not work under linuxBIOS.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/io.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#define PIIXE_IOBASE_RESOURCE 11
#define WINDOW_ADDR 0xfff00000
#define WINDOW_SIZE 0x00100000
#define BUSWIDTH 1
static u32 iobase;
#define IOBASE iobase
#define TRIBUF_PORT (IOBASE+0x37)
#define VPP_PORT (IOBASE+0x28)
static struct mtd_info *mymtd;
/* Is this really the vpp port? */
static DEFINE_SPINLOCK(l440gx_vpp_lock);
static int l440gx_vpp_refcnt;
static void l440gx_set_vpp(struct map_info *map, int vpp)
{
unsigned long flags;
spin_lock_irqsave(&l440gx_vpp_lock, flags);
if (vpp) {
if (++l440gx_vpp_refcnt == 1) /* first nested 'on' */
outl(inl(VPP_PORT) | 1, VPP_PORT);
} else {
if (--l440gx_vpp_refcnt == 0) /* last nested 'off' */
outl(inl(VPP_PORT) & ~1, VPP_PORT);
}
spin_unlock_irqrestore(&l440gx_vpp_lock, flags);
}
static struct map_info l440gx_map = {
.name = "L440GX BIOS",
.size = WINDOW_SIZE,
.bankwidth = BUSWIDTH,
.phys = WINDOW_ADDR,
#if 0
/* FIXME verify that this is the
* appripriate code for vpp enable/disable
*/
.set_vpp = l440gx_set_vpp
#endif
};
static int __init init_l440gx(void)
{
struct pci_dev *dev, *pm_dev;
struct resource *pm_iobase;
__u16 word;
dev = pci_get_device(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_82371AB_0, NULL);
pm_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_82371AB_3, NULL);
pci_dev_put(dev);
if (!dev || !pm_dev) {
printk(KERN_NOTICE "L440GX flash mapping: failed to find PIIX4 ISA bridge, cannot continue\n");
pci_dev_put(pm_dev);
return -ENODEV;
}
l440gx_map.virt = ioremap_nocache(WINDOW_ADDR, WINDOW_SIZE);
if (!l440gx_map.virt) {
printk(KERN_WARNING "Failed to ioremap L440GX flash region\n");
pci_dev_put(pm_dev);
return -ENOMEM;
}
simple_map_init(&l440gx_map);
printk(KERN_NOTICE "window_addr = 0x%08lx\n", (unsigned long)l440gx_map.virt);
/* Setup the pm iobase resource
* This code should move into some kind of generic bridge
* driver but for the moment I'm content with getting the
* allocation correct.
*/
pm_iobase = &pm_dev->resource[PIIXE_IOBASE_RESOURCE];
if (!(pm_iobase->flags & IORESOURCE_IO)) {
pm_iobase->name = "pm iobase";
pm_iobase->start = 0;
pm_iobase->end = 63;
pm_iobase->flags = IORESOURCE_IO;
/* Put the current value in the resource */
pci_read_config_dword(pm_dev, 0x40, &iobase);
iobase &= ~1;
pm_iobase->start += iobase & ~1;
pm_iobase->end += iobase & ~1;
pci_dev_put(pm_dev);
/* Allocate the resource region */
if (pci_assign_resource(pm_dev, PIIXE_IOBASE_RESOURCE) != 0) {
pci_dev_put(dev);
pci_dev_put(pm_dev);
printk(KERN_WARNING "Could not allocate pm iobase resource\n");
iounmap(l440gx_map.virt);
return -ENXIO;
}
}
/* Set the iobase */
iobase = pm_iobase->start;
pci_write_config_dword(pm_dev, 0x40, iobase | 1);
/* Set XBCS# */
pci_read_config_word(dev, 0x4e, &word);
word |= 0x4;
pci_write_config_word(dev, 0x4e, word);
/* Supply write voltage to the chip */
l440gx_set_vpp(&l440gx_map, 1);
/* Enable the gate on the WE line */
outb(inb(TRIBUF_PORT) & ~1, TRIBUF_PORT);
printk(KERN_NOTICE "Enabled WE line to L440GX BIOS flash chip.\n");
mymtd = do_map_probe("jedec_probe", &l440gx_map);
if (!mymtd) {
printk(KERN_NOTICE "JEDEC probe on BIOS chip failed. Using ROM\n");
mymtd = do_map_probe("map_rom", &l440gx_map);
}
if (mymtd) {
mymtd->owner = THIS_MODULE;
mtd_device_register(mymtd, NULL, 0);
return 0;
}
iounmap(l440gx_map.virt);
return -ENXIO;
}
static void __exit cleanup_l440gx(void)
{
mtd_device_unregister(mymtd);
map_destroy(mymtd);
iounmap(l440gx_map.virt);
}
module_init(init_l440gx);
module_exit(cleanup_l440gx);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("MTD map driver for BIOS chips on Intel L440GX motherboards");