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efi: Use a fixed value for the timer clock

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It is not yet clear how to read the timer via EFI. The current value seems
much too high on a Framework laptop I tried. Adjust it to a lower
hard-coded value for now.

Signed-off-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Simon Glass 2023-03-10 12:47:15 -08:00 • committed by Heinrich Schuchardt
parent 40b8afe6f6
commit 4f9a8f33f0
1 changed files with 9 additions and 0 deletions
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9
drivers/timer/tsc_timer.c
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@ -404,6 +404,15 @@ static void tsc_timer_ensure_setup(bool early)
if (!gd->arch.clock_rate) { if (!gd->arch.clock_rate) {
unsigned long fast_calibrate; unsigned long fast_calibrate;
/**
* There is no obvious way to obtain this information from EFI
* boot services. This value was measured on a Framework Laptop
* which has a 12th Gen Intel Core
*/
if (IS_ENABLED(CONFIG_EFI_APP)) {
fast_calibrate = 2750;
goto done;
}
fast_calibrate = native_calibrate_tsc(); fast_calibrate = native_calibrate_tsc();
if (fast_calibrate) if (fast_calibrate)
goto done; goto done;