LXR linux/tools/power/cpupower/utils/helpers/amd.c

   1// SPDX-License-Identifier: GPL-2.0
   2#if defined(__i386__) || defined(__x86_64__)
   3#include <unistd.h>
   4#include <errno.h>
   5#include <stdio.h>
   6#include <stdint.h>
   7
   8#include <pci/pci.h>
   9
  10#include "helpers/helpers.h"
  11
  12#define MSR_AMD_PSTATE_STATUS   0xc0010063
  13#define MSR_AMD_PSTATE          0xc0010064
  14#define MSR_AMD_PSTATE_LIMIT    0xc0010061
  15
  16union msr_pstate {
  17        struct {
  18                unsigned fid:6;
  19                unsigned did:3;
  20                unsigned vid:7;
  21                unsigned res1:6;
  22                unsigned nbdid:1;
  23                unsigned res2:2;
  24                unsigned nbvid:7;
  25                unsigned iddval:8;
  26                unsigned idddiv:2;
  27                unsigned res3:21;
  28                unsigned en:1;
  29        } bits;
  30        struct {
  31                unsigned fid:8;
  32                unsigned did:6;
  33                unsigned vid:8;
  34                unsigned iddval:8;
  35                unsigned idddiv:2;
  36                unsigned res1:30;
  37                unsigned en:1;
  38        } fam17h_bits;
  39        unsigned long long val;
  40};
  41
  42static int get_did(int family, union msr_pstate pstate)
  43{
  44        int t;
  45
  46        if (family == 0x12)
  47                t = pstate.val & 0xf;
  48        else if (family == 0x17)
  49                t = pstate.fam17h_bits.did;
  50        else
  51                t = pstate.bits.did;
  52
  53        return t;
  54}
  55
  56static int get_cof(int family, union msr_pstate pstate)
  57{
  58        int t;
  59        int fid, did, cof;
  60
  61        did = get_did(family, pstate);
  62        if (family == 0x17) {
  63                fid = pstate.fam17h_bits.fid;
  64                cof = 200 * fid / did;
  65        } else {
  66                t = 0x10;
  67                fid = pstate.bits.fid;
  68                if (family == 0x11)
  69                        t = 0x8;
  70                cof = (100 * (fid + t)) >> did;
  71        }
  72        return cof;
  73}
  74
  75/* Needs:
  76 * cpu          -> the cpu that gets evaluated
  77 * cpu_family   -> The cpu's family (0x10, 0x12,...)
  78 * boots_states -> how much boost states the machines support
  79 *
  80 * Fills up:
  81 * pstates -> a pointer to an array of size MAX_HW_PSTATES
  82 *            must be initialized with zeros.
  83 *            All available  HW pstates (including boost states)
  84 * no      -> amount of pstates above array got filled up with
  85 *
  86 * returns zero on success, -1 on failure
  87 */
  88int decode_pstates(unsigned int cpu, unsigned int cpu_family,
  89                   int boost_states, unsigned long *pstates, int *no)
  90{
  91        int i, psmax, pscur;
  92        union msr_pstate pstate;
  93        unsigned long long val;
  94
  95        /* Only read out frequencies from HW when CPU might be boostable
  96           to keep the code as short and clean as possible.
  97           Otherwise frequencies are exported via ACPI tables.
  98        */
  99        if (cpu_family < 0x10 || cpu_family == 0x14)
 100                return -1;
 101
 102        if (read_msr(cpu, MSR_AMD_PSTATE_LIMIT, &val))
 103                return -1;
 104
 105        psmax = (val >> 4) & 0x7;
 106
 107        if (read_msr(cpu, MSR_AMD_PSTATE_STATUS, &val))
 108                return -1;
 109
 110        pscur = val & 0x7;
 111
 112        pscur += boost_states;
 113        psmax += boost_states;
 114        for (i = 0; i <= psmax; i++) {
 115                if (i >= MAX_HW_PSTATES) {
 116                        fprintf(stderr, "HW pstates [%d] exceeding max [%d]\n",
 117                                psmax, MAX_HW_PSTATES);
 118                        return -1;
 119                }
 120                if (read_msr(cpu, MSR_AMD_PSTATE + i, &pstate.val))
 121                        return -1;
 122                pstates[i] = get_cof(cpu_family, pstate);
 123        }
 124        *no = i;
 125        return 0;
 126}
 127
 128int amd_pci_get_num_boost_states(int *active, int *states)
 129{
 130        struct pci_access *pci_acc;
 131        struct pci_dev *device;
 132        uint8_t val = 0;
 133
 134        *active = *states = 0;
 135
 136        device = pci_slot_func_init(&pci_acc, 0x18, 4);
 137
 138        if (device == NULL)
 139                return -ENODEV;
 140
 141        val = pci_read_byte(device, 0x15c);
 142        if (val & 3)
 143                *active = 1;
 144        else
 145                *active = 0;
 146        *states = (val >> 2) & 7;
 147
 148        pci_cleanup(pci_acc);
 149        return 0;
 150}
 151#endif /* defined(__i386__) || defined(__x86_64__) */
 152