soc/intel/cannonlake: Add chip config to override CPU flex ratio

This patch provides options to override descriptor default CPU flex
ratio from coreboot code. cpu_ratio_override to provide the required CPU
ratio.

Note: Don't override the flex ratio if cpu_ratio is 0.

BUG=b:142264107
TEST=Without override flex_ratio is 0 and verified booting to
OS after overriding with flex_ratio value 5.

Change-Id: Ib01650f52f3d402f669e7e7f5b28a648b86f08ec
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36864
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
This commit is contained in:
Subrata Banik 2019-11-18 14:08:08 +05:30 committed by Patrick Georgi
parent 433acc2d3d
commit e1470ea6a3
2 changed files with 21 additions and 4 deletions

View File

@ -424,6 +424,19 @@ struct soc_intel_cannonlake_config {
* Bit 0: MISCCFG_GPDLCGEN
*/
uint8_t gpio_pm[TOTAL_GPIO_COMM];
/*
* Override CPU flex ratio value:
* CPU ratio value controls the maximum processor non-turbo ratio.
* Valid Range 0 to 63.
*
* In general descriptor provides option to set default cpu flex ratio.
* Default cpu flex ratio is 0 ensures booting with non-turbo max frequency.
* Thats the reason FSP skips cpu_ratio override if cpu_ratio is 0.
*
* Only override CPU flex ratio if don't want to boot with non-turbo max.
*/
uint8_t cpu_ratio_override;
};
typedef struct soc_intel_cannonlake_config config_t;

View File

@ -74,10 +74,14 @@ static void soc_memory_init_params(FSP_M_CONFIG *m_cfg, const config_t *config)
m_cfg->SkipMpInit = !CONFIG_USE_INTEL_FSP_MP_INIT;
#endif
/* Set CpuRatio to match existing MSR value */
msr_t flex_ratio;
flex_ratio = rdmsr(MSR_FLEX_RATIO);
m_cfg->CpuRatio = (flex_ratio.lo >> 8) & 0xff;
if (config->cpu_ratio_override) {
m_cfg->CpuRatio = config->cpu_ratio_override;
} else {
/* Set CpuRatio to match existing MSR value */
msr_t flex_ratio;
flex_ratio = rdmsr(MSR_FLEX_RATIO);
m_cfg->CpuRatio = (flex_ratio.lo >> 8) & 0xff;
}
/* If ISH is enabled, enable ISH elements */
if (!dev)