diff options
| author | Pallipadi, Venkatesh <venkatesh.pallipadi@intel.com> | 2010-01-21 11:09:52 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-01-23 06:21:58 +0100 |
| commit | 73472a46b5b28116b145fb5fc05242c1aa8e1461 (patch) | |
| tree | bbcb6174edb2ea3c94e64bbfe7f92f3f128d96d3 /arch | |
| parent | 3a5fc0e40cb467e692737bc798bc99773c81e1e2 (diff) | |
| download | kernel_samsung_smdk4412-73472a46b5b28116b145fb5fc05242c1aa8e1461.zip kernel_samsung_smdk4412-73472a46b5b28116b145fb5fc05242c1aa8e1461.tar.gz kernel_samsung_smdk4412-73472a46b5b28116b145fb5fc05242c1aa8e1461.tar.bz2 | |
x86: Disable HPET MSI on ATI SB700/SB800
HPET MSI on platforms with ATI SB700/SB800 as they seem to have some
side-effects on floppy DMA. Do not use HPET MSI on such platforms.
Original problem report from Mark Hounschell
http://lkml.indiana.edu/hypermail/linux/kernel/0912.2/01118.html
[ This patch needs to go to stable as well. But, there are some
conflicts that prevents the patch from going as is. I can
rebase/resubmit to stable once the patch goes upstream.
hpa: still Cc:'ing stable@ as an FYI. ]
Tested-by: Mark Hounschell <markh@compro.net>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: <stable@kernel.org>
LKML-Reference: <20100121190952.GA32523@linux-os.sc.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/hpet.h | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/hpet.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/quirks.c | 13 |
3 files changed, 22 insertions, 0 deletions
diff --git a/arch/x86/include/asm/hpet.h b/arch/x86/include/asm/hpet.h index 5d89fd2..1d5c08a 100644 --- a/arch/x86/include/asm/hpet.h +++ b/arch/x86/include/asm/hpet.h @@ -67,6 +67,7 @@ extern unsigned long hpet_address; extern unsigned long force_hpet_address; extern u8 hpet_blockid; extern int hpet_force_user; +extern u8 hpet_msi_disable; extern int is_hpet_enabled(void); extern int hpet_enable(void); extern void hpet_disable(void); diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index ba6e658..ad80a1c 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -34,6 +34,8 @@ */ unsigned long hpet_address; u8 hpet_blockid; /* OS timer block num */ +u8 hpet_msi_disable; + #ifdef CONFIG_PCI_MSI static unsigned long hpet_num_timers; #endif @@ -596,6 +598,9 @@ static void hpet_msi_capability_lookup(unsigned int start_timer) unsigned int num_timers_used = 0; int i; + if (hpet_msi_disable) + return; + if (boot_cpu_has(X86_FEATURE_ARAT)) return; id = hpet_readl(HPET_ID); @@ -928,6 +933,9 @@ static __init int hpet_late_init(void) hpet_reserve_platform_timers(hpet_readl(HPET_ID)); hpet_print_config(); + if (hpet_msi_disable) + return 0; + if (boot_cpu_has(X86_FEATURE_ARAT)) return 0; diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c index 18093d7..12e9fea 100644 --- a/arch/x86/kernel/quirks.c +++ b/arch/x86/kernel/quirks.c @@ -491,6 +491,19 @@ void force_hpet_resume(void) break; } } + +/* + * HPET MSI on some boards (ATI SB700/SB800) has side effect on + * floppy DMA. Disable HPET MSI on such platforms. + */ +static void force_disable_hpet_msi(struct pci_dev *unused) +{ + hpet_msi_disable = 1; +} + +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS, + force_disable_hpet_msi); + #endif #if defined(CONFIG_PCI) && defined(CONFIG_NUMA) |