x86: Save TSC frequency in the global data

Return the saved TSC frequency in get_tbclk_mhz().

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

diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
index 3e3073a..186b97e 100644 (file)
--- a/arch/x86/include/asm/global_data.h
+++ b/arch/x86/include/asm/global_data.h
@@ -21,6 +21,7 @@ struct arch_global_data {
        uint64_t tsc_base;              /* Initial value returned by rdtsc() */
        uint32_t tsc_base_kclocks;      /* Initial tsc as a kclocks value */
        uint32_t tsc_prev;              /* For show_boot_progress() */
+       uint32_t tsc_mhz;               /* TSC frequency in MHz */
        void *new_fdt;                  /* Relocated FDT */
        uint32_t bist;                  /* Built-in self test value */
 };

diff --git a/arch/x86/lib/tsc_timer.c b/arch/x86/lib/tsc_timer.c
index ceff60c..f091c91 100644 (file)
--- a/arch/x86/lib/tsc_timer.c
+++ b/arch/x86/lib/tsc_timer.c
@@ -293,6 +293,9 @@ unsigned __attribute__((no_instrument_function)) long get_tbclk_mhz(void)
 {
        unsigned long fast_calibrate;
 
+       if (gd->arch.tsc_mhz)
+               return gd->arch.tsc_mhz;
+
        fast_calibrate = try_msr_calibrate_tsc();
        if (fast_calibrate)
                return fast_calibrate;
@@ -301,6 +304,7 @@ unsigned __attribute__((no_instrument_function)) long get_tbclk_mhz(void)
        if (!fast_calibrate)
                panic("TSC frequency is ZERO");
 
+       gd->arch.tsc_mhz = fast_calibrate;
        return fast_calibrate;
 }