x86: Don't set up MTRRs if previously done

When starting U-Boot from a previous-stage bootloader we presumably don't
need to set up the variable MTRRs. In fact this could be harmful if the
existing settings are not what U-Boot uses.

Skip that step in this case.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/arch/x86/cpu/i386/cpu.c b/arch/x86/cpu/i386/cpu.c
index e59215c..c7f6c5a 100644 (file)
--- a/arch/x86/cpu/i386/cpu.c
+++ b/arch/x86/cpu/i386/cpu.c
@@ -423,7 +423,7 @@ static void setup_mtrr(void)
        u64 mtrr_cap;
 
        /* Configure fixed range MTRRs for some legacy regions */
-       if (!gd->arch.has_mtrr)
+       if (!gd->arch.has_mtrr || !ll_boot_init())
                return;
 
        mtrr_cap = native_read_msr(MTRR_CAP_MSR);