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/x86/kernel/hpet.c | |
| parent | 3a5fc0e40cb467e692737bc798bc99773c81e1e2 (diff) | |
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/x86/kernel/hpet.c')
| -rw-r--r-- | arch/x86/kernel/hpet.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index ba6e65884603..ad80a1c718c6 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; |