Re: [PATCH 2/3] x86, intel: Use cpu_update for Atom errata check

Jean Delvare
2011-05-26T07:40:53Z

On Wed, 25 May 2011 12:32:27 -0700, Andi Kleen wrote:
> From: Andi Kleen <ak@linux.intel.com>
>
> Now that the cpu update level is available the Atom PSE errata
> check can use it directly without reading the MSR again.
>
> Signed-off-by: Andi Kleen <ak@linux.intel.com>

Acked-by: Jean Delvare <khali@linux-fr.org>

> ---
> arch/x86/kernel/cpu/intel.c | 15 ++++-----------
> 1 files changed, 4 insertions(+), 11 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
> index ba5ba17..701efa4 100644
> --- a/arch/x86/kernel/cpu/intel.c
> +++ b/arch/x86/kernel/cpu/intel.c
> @@ -55,17 +55,10 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
> * need the microcode to have already been loaded... so if it is
> * not, recommend a BIOS update and disable large pages.
> */
> - if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2) {
> - u32 ucode, junk;
> -
> - wrmsr(MSR_IA32_UCODE_REV, 0, 0);
> - sync_core();
> - rdmsr(MSR_IA32_UCODE_REV, junk, ucode);
> -
> - if (ucode < 0x20e) {
> - printk(KERN_WARNING "Atom PSE erratum detected, BIOS microcode update recommended\n");
> - clear_cpu_cap(c, X86_FEATURE_PSE);
> - }
> + if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2 &&
> + c->cpu_update < 0x20e) {
> + printk(KERN_WARNING "Atom PSE erratum detected, BIOS microcode update recommended\n");
> + clear_cpu_cap(c, X86_FEATURE_PSE);
> }
>
> #ifdef CONFIG_X86_64

--
Jean Delvare