[34-longterm 210/260] intel_idle: PCI quirk to prevent Lenovo Ideapad s10-3 boot hang

Paul Gortmaker
2011-01-02T07:27:42Z

From: Len Brown <len.brown@intel.com>

commit 4731fdcf6f7bdab3e369a3f844d4ea4d4017284d upstream.

When the Lenovo Ideapad S10-3 is booted with HT enabled,
it hits a boot hang in the intel_idle driver.

This occurs when entering ATM-C4 for the first time,
unless BM_STS is first cleared.

acpi_idle doesn't see this because it first checks
and clears BM_STS, but it would hit the same hang
if that check were disabled.

http://bugs.meego.com/show_bug.cgi?id=7093
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/634702

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
drivers/pci/quirks.c | 20 ++++++++++++++++++++
1 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index c582935..4a120b7 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -150,6 +150,26 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NEC, PCI_DEVICE_ID_NEC_CBUS_2, quirk_isa_d
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NEC, PCI_DEVICE_ID_NEC_CBUS_3, quirk_isa_dma_hangs);

/*
+ * Intel NM10 "TigerPoint" LPC PM1a_STS.BM_STS must be clear
+ * for some HT machines to use C4 w/o hanging.
+ */
+static void __devinit quirk_tigerpoint_bm_sts(struct pci_dev *dev)
+{
+ u32 pmbase;
+ u16 pm1a;
+
+ pci_read_config_dword(dev, 0x40, &pmbase);
+ pmbase = pmbase & 0xff80;
+ pm1a = inw(pmbase);
+
+ if (pm1a & 0x10) {
+ dev_info(&dev->dev, FW_BUG "TigerPoint LPC.BM_STS cleared\n");
+ outw(0x10, pmbase);
+ }
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TGP_LPC, quirk_tigerpoint_bm_sts);
+
+/*
* Chipsets where PCI->PCI transfers vanish or hang
*/
static void __devinit quirk_nopcipci(struct pci_dev *dev)
--
1.7.3.3