src/cpu/intel/model_206ax/bootblock.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <arch/bootblock.h>
   4 #include <arch/io.h>
   5 #include <cpu/cpu.h>
   6 #include <cpu/x86/msr.h>
   7 #include <halt.h>
   8 #include <stdint.h>
   9
  10 #include "model_206ax.h"
  11
  12 #if CONFIG(SOUTHBRIDGE_INTEL_BD82X6X) || \
  13         CONFIG(SOUTHBRIDGE_INTEL_C216)
  14 /* Needed for RCBA access to set Soft Reset Data register */
  15 #include <southbridge/intel/bd82x6x/pch.h>
  16 #else
  17 #error "CPU must be paired with Intel BD82X6X or C216 southbridge"
  18 #endif
  19
  20 static void set_flex_ratio_to_tdp_nominal(void)
  21 {
  22         msr_t flex_ratio, msr;
  23         u32 soft_reset;
  24         u8 nominal_ratio;
  25
  26         /* Minimum CPU revision for configurable TDP support */
  27         if (cpuid_eax(1) < IVB_CONFIG_TDP_MIN_CPUID)
  28                 return;
  29
  30         /* Check for Flex Ratio support */
  31         flex_ratio = rdmsr(MSR_FLEX_RATIO);
  32         if (!(flex_ratio.lo & FLEX_RATIO_EN))
  33                 return;
  34
  35         /* Check for >0 configurable TDPs */
  36         msr = rdmsr(MSR_PLATFORM_INFO);
  37         if (((msr.hi >> 1) & 3) == 0)
  38                 return;
  39
  40         /* Use nominal TDP ratio for flex ratio */
  41         msr = rdmsr(MSR_CONFIG_TDP_NOMINAL);
  42         nominal_ratio = msr.lo & 0xff;
  43
  44         /* See if flex ratio is already set to nominal TDP ratio */
  45         if (((flex_ratio.lo >> 8) & 0xff) == nominal_ratio)
  46                 return;
  47
  48         /* Set flex ratio to nominal TDP ratio */
  49         flex_ratio.lo &= ~0xff00;
  50         flex_ratio.lo |= nominal_ratio << 8;
  51         flex_ratio.lo |= FLEX_RATIO_LOCK;
  52         wrmsr(MSR_FLEX_RATIO, flex_ratio);
  53
  54         /* Set flex ratio in soft reset data register bits 11:6.
  55          * RCBA region is enabled in southbridge bootblock */
  56         soft_reset = RCBA32(SOFT_RESET_DATA);
  57         soft_reset &= ~(0x3f << 6);
  58         soft_reset |= (nominal_ratio & 0x3f) << 6;
  59         RCBA32(SOFT_RESET_DATA) = soft_reset;
  60
  61         /* Set soft reset control to use register value */
  62         RCBA32_OR(SOFT_RESET_CTRL, 1);
  63
  64         /* Issue warm reset, will be "CPU only" due to soft reset data */
  65         outb(0x0, 0xcf9);
  66         outb(0x6, 0xcf9);
  67         halt();
  68 }
  69
  70 void bootblock_early_cpu_init(void)
  71 {
  72         /* Set flex ratio and reset if needed */
  73         set_flex_ratio_to_tdp_nominal();
  74 }