diff options
| -rw-r--r-- | src/cpu/intel/model_206ax/acpi.c | 64 |
1 files changed, 59 insertions, 5 deletions
diff --git a/src/cpu/intel/model_206ax/acpi.c b/src/cpu/intel/model_206ax/acpi.c index c4f58397e8..f3bd67be4b 100644 --- a/src/cpu/intel/model_206ax/acpi.c +++ b/src/cpu/intel/model_206ax/acpi.c @@ -87,23 +87,77 @@ static void print_supported_cstates(void) printk(BIOS_DEBUG, "\n"); } +/* + * Returns the supported C-state or the next lower one that + * is supported. + */ +static int get_supported_cstate(int cstate) +{ + uint8_t state, substate; + size_t i; + + assert(cstate < NUM_C_STATES); + + for (i = cstate; i > 0; i--) { + state = (cstate_map[i].resource.addrl >> 4) + 1; + substate = cstate_map[i].resource.addrl & 0xf; + if (cpu_get_c_substate_support(state) > substate) + break; + } + + if (cstate != i) + printk(BIOS_INFO, "Requested C-state %s not supported, using %s instead\n", + c_state_names[cstate], c_state_names[i]); + + return i; +} + static void generate_C_state_entries(const struct device *dev) { struct cpu_intel_model_206ax_config *conf = dev->chip_info; - const int acpi_cstates[3] = { conf->acpi_c1, conf->acpi_c2, conf->acpi_c3 }; + int acpi_cstates[3] = { conf->acpi_c1, conf->acpi_c2, conf->acpi_c3 }; acpi_cstate_t acpi_cstate_map[ARRAY_SIZE(acpi_cstates)] = { 0 }; /* Count number of active C-states */ int count = 0; for (int i = 0; i < ARRAY_SIZE(acpi_cstates); i++) { - if (acpi_cstates[i] > 0 && acpi_cstates[i] < ARRAY_SIZE(cstate_map)) { - acpi_cstate_map[count] = cstate_map[acpi_cstates[i]]; - acpi_cstate_map[count].ctype = i + 1; - count++; + /* Remove invalid states */ + if (acpi_cstates[i] >= ARRAY_SIZE(cstate_map)) { + printk(BIOS_ERR, "Invalid C-state in devicetree: %d\n", + acpi_cstates[i]); + acpi_cstates[i] = 0; + continue; + } + /* Skip C0, it's always supported */ + if (acpi_cstates[i] == 0) + continue; + + /* Find supported state. Might downgrade a state. */ + acpi_cstates[i] = get_supported_cstate(acpi_cstates[i]); + + /* Remove duplicate states */ + for (int j = i - 1; j >= 0; j--) { + if (acpi_cstates[i] == acpi_cstates[j]) { + acpi_cstates[i] = 0; + break; + } } } + + /* Convert C-state to ACPI C-states */ + for (int i = 0; i < ARRAY_SIZE(acpi_cstates); i++) { + if (acpi_cstates[i] == 0) + continue; + acpi_cstate_map[count] = cstate_map[acpi_cstates[i]]; + acpi_cstate_map[count].ctype = i + 1; + + count++; + printk(BIOS_DEBUG, "Advertising ACPI C State type C%d as CPU %s\n", + i + 1, c_state_names[acpi_cstates[i]]); + } + acpigen_write_CST_package(acpi_cstate_map, count); } |