/* SPDX-License-Identifier: GPL-2.0-only */ #include <assert.h> #include <bootstate.h> #include <cbfs.h> #include <console/console.h> #include <device/device.h> #include <ec/google/chromeec/ec.h> #include <fw_config.h> #include <inttypes.h> #include <lib.h> #include <drivers/vpd/vpd.h> uint64_t fw_config_get(void) { static uint64_t fw_config_value; static bool fw_config_value_initialized; /* Nothing to prepare if setup is already done. */ if (fw_config_value_initialized) return fw_config_value; fw_config_value_initialized = true; fw_config_value = UNDEFINED_FW_CONFIG; /* Read the value from EC CBI. */ if (CONFIG(FW_CONFIG_SOURCE_CHROMEEC_CBI)) { if (google_chromeec_cbi_get_fw_config(&fw_config_value)) printk(BIOS_WARNING, "%s: Could not get fw_config from CBI\n", __func__); else printk(BIOS_INFO, "FW_CONFIG value from CBI is 0x%" PRIx64 "\n", fw_config_value); } /* Look in CBFS to allow override of value. */ if (CONFIG(FW_CONFIG_SOURCE_CBFS) && fw_config_value == UNDEFINED_FW_CONFIG) { if (cbfs_load(CONFIG_CBFS_PREFIX "/fw_config", &fw_config_value, sizeof(fw_config_value)) != sizeof(fw_config_value)) printk(BIOS_WARNING, "%s: Could not get fw_config from CBFS\n", __func__); else printk(BIOS_INFO, "FW_CONFIG value from CBFS is 0x%" PRIx64 "\n", fw_config_value); } if (CONFIG(FW_CONFIG_SOURCE_VPD) && fw_config_value == UNDEFINED_FW_CONFIG) { int vpd_value; if (vpd_get_int("fw_config", VPD_RW_THEN_RO, &vpd_value)) { fw_config_value = vpd_value; printk(BIOS_INFO, "FW_CONFIG value from VPD is 0x%" PRIx64 "\n", fw_config_value); } else printk(BIOS_WARNING, "%s: Could not get fw_config from vpd\n", __func__); } return fw_config_value; } uint64_t fw_config_get_field(const struct fw_config_field *field) { /* If fw_config is not provisioned, then there is nothing to get. */ if (!fw_config_is_provisioned()) return UNDEFINED_FW_CONFIG; int shift = __ffs64(field->mask); const uint64_t value = (fw_config_get() & field->mask) >> shift; printk(BIOS_INFO, "fw_config get field name=%s, mask=0x%" PRIx64 ", shift=%d, value=0x%" PRIx64 "\n", field->field_name, field->mask, shift, value); return value; } bool fw_config_probe(const struct fw_config *match) { /* If fw_config is not provisioned, then there is nothing to match. */ if (!fw_config_is_provisioned()) return false; /* Compare to system value. */ if ((fw_config_get() & match->mask) == match->value) { if (match->field_name && match->option_name) printk(BIOS_INFO, "fw_config match found: %s=%s\n", match->field_name, match->option_name); else printk(BIOS_INFO, "fw_config match found: mask=0x%" PRIx64 " value=0x%" PRIx64 "\n", match->mask, match->value); return true; } return false; } bool fw_config_probe_dev(const struct device *dev, const struct fw_config **matching_probe) { const struct fw_config *probe; if (matching_probe) *matching_probe = NULL; /* If the device does not have a probe list, then probing is not required. */ if (!dev->probe_list) return true; for (probe = dev->probe_list; probe && probe->mask != 0; probe++) { if (!fw_config_probe(probe)) continue; if (matching_probe) *matching_probe = probe; return true; } return false; } #if ENV_RAMSTAGE /* * The maximum number of fw_config fields is limited by the 64-bit mask that is used to * represent them. */ #define MAX_CACHE_ELEMENTS (8 * sizeof(uint64_t)) static const struct fw_config *cached_configs[MAX_CACHE_ELEMENTS]; static size_t probe_index(uint64_t mask) { assert(mask); return __ffs64(mask); } const struct fw_config *fw_config_get_found(uint64_t field_mask) { const struct fw_config *config; config = cached_configs[probe_index(field_mask)]; if (config && config->mask == field_mask) return config; return NULL; } void fw_config_for_each_found(void (*cb)(const struct fw_config *config, void *arg), void *arg) { size_t i; for (i = 0; i < MAX_CACHE_ELEMENTS; ++i) if (cached_configs[i]) cb(cached_configs[i], arg); } static void fw_config_init(void *unused) { struct device *dev; for (dev = all_devices; dev; dev = dev->next) { const struct fw_config *probe; if (!fw_config_probe_dev(dev, &probe)) { printk(BIOS_INFO, "%s disabled by fw_config\n", dev_path(dev)); dev->enabled = 0; continue; } if (probe) cached_configs[probe_index(probe->mask)] = probe; } } BOOT_STATE_INIT_ENTRY(BS_DEV_INIT_CHIPS, BS_ON_ENTRY, fw_config_init, NULL); #endif