kernel-ark/arch/i386/kernel/reboot_fixups.c
Andres Salomon 95069f89e8 GEODE: reboot fixup for geode machines with CS5536 boards
Writing to MSR 0x51400017 forces a hard reset on CS5536-based machines,
this has the reboot fixup do just that if such a board is detected.

Acked-by: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-06 11:45:11 -07:00

69 lines
1.7 KiB
C

/*
* linux/arch/i386/kernel/reboot_fixups.c
*
* This is a good place to put board specific reboot fixups.
*
* List of supported fixups:
* geode-gx1/cs5530a - Jaya Kumar <jayalk@intworks.biz>
* geode-gx/lx/cs5536 - Andres Salomon <dilinger@debian.org>
*
*/
#include <asm/delay.h>
#include <linux/pci.h>
#include <asm/reboot_fixups.h>
#include <asm/msr.h>
static void cs5530a_warm_reset(struct pci_dev *dev)
{
/* writing 1 to the reset control register, 0x44 causes the
cs5530a to perform a system warm reset */
pci_write_config_byte(dev, 0x44, 0x1);
udelay(50); /* shouldn't get here but be safe and spin-a-while */
return;
}
static void cs5536_warm_reset(struct pci_dev *dev)
{
/*
* 6.6.2.12 Soft Reset (DIVIL_SOFT_RESET)
* writing 1 to the LSB of this MSR causes a hard reset.
*/
wrmsrl(0x51400017, 1ULL);
udelay(50); /* shouldn't get here but be safe and spin a while */
}
struct device_fixup {
unsigned int vendor;
unsigned int device;
void (*reboot_fixup)(struct pci_dev *);
};
static struct device_fixup fixups_table[] = {
{ PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY, cs5530a_warm_reset },
{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA, cs5536_warm_reset },
};
/*
* we see if any fixup is available for our current hardware. if there
* is a fixup, we call it and we expect to never return from it. if we
* do return, we keep looking and then eventually fall back to the
* standard mach_reboot on return.
*/
void mach_reboot_fixups(void)
{
struct device_fixup *cur;
struct pci_dev *dev;
int i;
for (i=0; i < ARRAY_SIZE(fixups_table); i++) {
cur = &(fixups_table[i]);
dev = pci_get_device(cur->vendor, cur->device, NULL);
if (!dev)
continue;
cur->reboot_fixup(dev);
}
}