[U-Boot] [PATCH 21/22] x86: ivybridge: Update microcode early in boot

[Bin Meng]

Hi Simon,

On Sun, Dec 28, 2014 at 10:20 AM, Simon Glass <sjg at chromium.org> wrote:
> At present the normal update (which happens much later) does not work. This
> seems to have something to do with the 'no eviction' mode in the CAR, or at
> least moving the microcode update after that causes it not to work.
>
> For now, do an update early on so that it definitely works. Also refuse to
> continue unless the microcode update check (later in boot) is successful.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
>  arch/x86/cpu/ivybridge/car.S             | 14 ++++++++++++++
>  arch/x86/cpu/ivybridge/cpu.c             |  2 +-
>  arch/x86/cpu/ivybridge/microcode_intel.c |  9 +++++++--
>  arch/x86/dts/link.dts                    |  3 ---
>  4 files changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/cpu/ivybridge/car.S b/arch/x86/cpu/ivybridge/car.S
> index 6e7e1e4..95da087 100644
> --- a/arch/x86/cpu/ivybridge/car.S
> +++ b/arch/x86/cpu/ivybridge/car.S
> @@ -45,6 +45,14 @@ car_init:
>         movl    $0xFEE00300, %esi
>         movl    %eax, (%esi)
>
> +       /* TODO: Load microcode later - the 'no eviction' mode breaks this */
> +       movl    $0x79, %ecx

Replace 0x79 to MSR_IA32_UCODE_WRITE from msr-index.h

> +       xorl    %edx, %edx
> +       movl    $_dt_ucode_base_size, %eax
> +       movl    (%eax), %eax
> +       addl    $0x30, %eax

And here 0x30 to something like MICROCODE_HEADER_LEN.

> +       wrmsr
> +
>         post_code(POST_CAR_SIPI)
>         /* Zero out all fixed range and variable range MTRRs */
>         movl    $mtrr_table, %esi
> @@ -228,3 +236,9 @@ mtrr_table:
>         .word 0x20C, 0x20D, 0x20E, 0x20F
>         .word 0x210, 0x211, 0x212, 0x213
>  mtrr_table_end:
> +
> +       .align 4
> +_dt_ucode_base_size:
> +       /* These next two fields are filled in by ifdtool */
> +       .long   0                       /* microcode base */
> +       .long   0                       /* microcode size */
> diff --git a/arch/x86/cpu/ivybridge/cpu.c b/arch/x86/cpu/ivybridge/cpu.c
> index 0543e06..e925310 100644
> --- a/arch/x86/cpu/ivybridge/cpu.c
> +++ b/arch/x86/cpu/ivybridge/cpu.c
> @@ -263,7 +263,7 @@ int print_cpuinfo(void)
>         enable_lapic();
>
>         ret = microcode_update_intel();

Since we already did the microcode update in car_init, why should we
do this again here?

> -       if (ret && ret != -ENOENT && ret != -EEXIST)
> +       if (ret)
>                 return ret;
>
>         /* Enable upper 128bytes of CMOS */
> diff --git a/arch/x86/cpu/ivybridge/microcode_intel.c b/arch/x86/cpu/ivybridge/microcode_intel.c
> index 0817751..c012820 100644
> --- a/arch/x86/cpu/ivybridge/microcode_intel.c
> +++ b/arch/x86/cpu/ivybridge/microcode_intel.c
> @@ -120,6 +120,7 @@ int microcode_update_intel(void)
>         int count;
>         int node;
>         int ret;
> +       int rev;
>
>         microcode_read_cpu(&cpu);
>         node = 0;
> @@ -147,12 +148,16 @@ int microcode_update_intel(void)
>                         skipped++;
>                         continue;
>                 }
> -               ret = microcode_read_rev();
>                 wrmsr(0x79, (ulong)update.data, 0);
> +               rev = microcode_read_rev();
>                 debug("microcode: updated to revision 0x%x date=%04x-%02x-%02x\n",
> -                     microcode_read_rev(), update.date_code & 0xffff,
> +                     rev, update.date_code & 0xffff,
>                       (update.date_code >> 24) & 0xff,
>                       (update.date_code >> 16) & 0xff);
> +               if (update.update_revision != rev) {
> +                       printf("Microcode update failed\n");
> +                       return -EFAULT;
> +               }
>                 count++;
>         } while (1);
>  }
> diff --git a/arch/x86/dts/link.dts b/arch/x86/dts/link.dts
> index a739080..1ebc334 100644
> --- a/arch/x86/dts/link.dts
> +++ b/arch/x86/dts/link.dts
> @@ -214,9 +214,6 @@
>
>         microcode {
>                 update at 0 {
> -#include "microcode/m12206a7_00000029.dtsi"
> -               };
> -               update at 1 {
>  #include "microcode/m12306a9_0000001b.dtsi"
>                 };
>         };
> --

Regards,
Bin