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>
diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index d2f6a24..b1b2b30 100644
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -441,8 +441,8 @@
this config is intended, is when reboot ends with a stalled/hung
system.
- Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
- combination.
+ Currently, the only fixup is for the Geode machines using
+ CS5530A and CS5536 chipsets.
Say Y if you want to enable the fixup. Currently, it's safe to
enable this option even if you don't need it.
diff --git a/arch/i386/kernel/reboot_fixups.c b/arch/i386/kernel/reboot_fixups.c
index 2d78d91..03e1cce 100644
--- a/arch/i386/kernel/reboot_fixups.c
+++ b/arch/i386/kernel/reboot_fixups.c
@@ -5,12 +5,14 @@
*
* 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)
{
@@ -21,6 +23,16 @@
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;
@@ -29,6 +41,7 @@
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 },
};
/*