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authorSimon Glass <sjg@chromium.org>2019-12-06 21:41:50 -0700
committerBin Meng <bmeng.cn@gmail.com>2019-12-15 11:44:10 +0800
commit642e8487ec629b43b1c5caf846098bfc952be5c0 (patch)
tree084b06a0418b7b7d3fbd3f43350361d2052ca701 /drivers/timer/tsc_timer.c
parent77dd7c6854f3bd8ddc422f0cb1953071fe00dc6c (diff)
x86: timer: Reduce timer code size in TPL on Intel CPUs
Most of the timer-calibration methods are not needed on recent Intel CPUs and just increase code size. Add an option to use the known-good way to get the clock frequency in TPL. Size reduction is about 700 bytes. Note that version 1 of this commit caused bootstage to crash since the CPU was not identified. This is corrected by changes previously applied to make sure that the CPU is identified before spl_init() is called, such as 39146a2e0b x86: Move CPU init to before spl_init() Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Diffstat (limited to 'drivers/timer/tsc_timer.c')
-rw-r--r--drivers/timer/tsc_timer.c7
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/timer/tsc_timer.c b/drivers/timer/tsc_timer.c
index 813817f467..43cb2d820e 100644
--- a/drivers/timer/tsc_timer.c
+++ b/drivers/timer/tsc_timer.c
@@ -50,8 +50,7 @@ static unsigned long native_calibrate_tsc(void)
return 0;
crystal_freq = tsc_info.ecx / 1000;
-
- if (!crystal_freq) {
+ if (!CONFIG_IS_ENABLED(X86_TSC_TIMER_NATIVE) && !crystal_freq) {
switch (gd->arch.x86_model) {
case INTEL_FAM6_SKYLAKE_MOBILE:
case INTEL_FAM6_SKYLAKE_DESKTOP:
@@ -407,6 +406,10 @@ static void tsc_timer_ensure_setup(bool early)
if (fast_calibrate)
goto done;
+ /* Reduce code size by dropping other methods */
+ if (CONFIG_IS_ENABLED(X86_TSC_TIMER_NATIVE))
+ panic("no timer");
+
fast_calibrate = cpu_mhz_from_cpuid();
if (fast_calibrate)
goto done;