From 242fd2810c86b82e5aea8f8244c13955dbd8b9db Mon Sep 17 00:00:00 2001 From: Angel Pons Date: Wed, 28 Oct 2020 23:48:56 +0100 Subject: cpu/intel/haswell: Allow tuning VR for C-state operations Apply commit ff0f460e76 (broadwell: Add configuration for tuning VR for C-state operations) to Haswell, in preparation for unification. Change-Id: Ib05974e8ed0f73c4f475b90065e8efb14555f9c9 Signed-off-by: Angel Pons Reviewed-on: https://review.coreboot.org/c/coreboot/+/46920 Reviewed-by: Nico Huber Tested-by: build bot (Jenkins) --- src/cpu/intel/haswell/chip.h | 29 +++++++++++++++++++++++++++++ src/cpu/intel/haswell/haswell_init.c | 23 +++++++++++++++++++++-- 2 files changed, 50 insertions(+), 2 deletions(-) diff --git a/src/cpu/intel/haswell/chip.h b/src/cpu/intel/haswell/chip.h index 6afed37616..7c2df103a0 100644 --- a/src/cpu/intel/haswell/chip.h +++ b/src/cpu/intel/haswell/chip.h @@ -3,6 +3,33 @@ /* Magic value used to locate this chip in the device tree */ #define SPEEDSTEP_APIC_MAGIC 0xACAC +#include +#include + +struct cpu_vr_config { + /* + * Minimum voltage for C6/C7 state: + * 0x67 = 1.6V (full swing) + * ... + * 0x79 = 1.7V + * ... + * 0x83 = 1.8V (no swing) + */ + uint8_t cpu_min_vid; + + /* + * Set slow VR ramp rate on C-state exit: + * 0 = Fast VR ramp rate / 2 + * 1 = Fast VR ramp rate / 4 + * 2 = Fast VR ramp rate / 8 + * 3 = Fast VR ramp rate / 16 + */ + uint8_t slow_ramp_rate_set; + + /* Enable slow VR ramp rate */ + bool slow_ramp_rate_enable; +}; + struct cpu_intel_haswell_config { int c1_battery; /* ACPI C1 on Battery Power */ int c2_battery; /* ACPI C2 on Battery Power */ @@ -13,4 +40,6 @@ struct cpu_intel_haswell_config { int c3_acpower; /* ACPI C3 on AC Power */ int tcc_offset; /* TCC Activation Offset */ + + struct cpu_vr_config vr_config; }; diff --git a/src/cpu/intel/haswell/haswell_init.c b/src/cpu/intel/haswell/haswell_init.c index 369ace9b45..dd1970c033 100644 --- a/src/cpu/intel/haswell/haswell_init.c +++ b/src/cpu/intel/haswell/haswell_init.c @@ -249,8 +249,17 @@ static u32 pcode_mailbox_read(u32 command) static void initialize_vr_config(void) { + struct cpu_vr_config vr_config = { 0 }; msr_t msr; + const struct device *lapic = dev_find_lapic(SPEEDSTEP_APIC_MAGIC); + + if (lapic && lapic->chip_info) { + const struct cpu_intel_haswell_config *conf = lapic->chip_info; + + vr_config = conf->vr_config; + } + printk(BIOS_DEBUG, "Initializing VR config.\n"); /* Configure VR_CURRENT_CONFIG. */ @@ -280,13 +289,23 @@ static void initialize_vr_config(void) msr.hi &= ~(1 << (51 - 32)); /* Enable decay mode on C-state entry. */ msr.hi |= (1 << (52 - 32)); + /* Set the slow ramp rate */ if (haswell_is_ult()) { - /* Set the slow ramp rate to be fast ramp rate / 4 */ msr.hi &= ~(0x3 << (53 - 32)); - msr.hi |= (0x01 << (53 - 32)); + /* Configure the C-state exit ramp rate. */ + if (vr_config.slow_ramp_rate_enable) { + /* Configured slow ramp rate. */ + msr.hi |= ((vr_config.slow_ramp_rate_set & 0x3) << (53 - 32)); + /* Set exit ramp rate to slow. */ + msr.hi &= ~(1 << (50 - 32)); + } else { + /* Fast ramp rate / 4. */ + msr.hi |= (1 << (53 - 32)); + } } /* Set MIN_VID (31:24) to allow CPU to have full control. */ msr.lo &= ~0xff000000; + msr.lo |= (vr_config.cpu_min_vid & 0xff) << 24; wrmsr(MSR_VR_MISC_CONFIG, msr); /* Configure VR_MISC_CONFIG2 MSR. */ -- cgit v1.2.3