secure_boot: Checks secure boot efuses

ESP32 V1 and V2 - protection bits.
ESP32xx V2: revoke bits, protection bits

- refactor efuse component
- adds some APIs for esp32 chips as well as for esp32xx chips

components/efuse/esp32s3/esp_efuse_fields.c

@@ -0,0 +1,75 @@
+// Copyright 2017-2020 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "esp_efuse.h"
+#include "esp_efuse_utility.h"
+#include "esp_efuse_table.h"
+#include "stdlib.h"
+#include "esp_types.h"
+#include "assert.h"
+#include "esp_err.h"
+#include "esp_log.h"
+#include "soc/efuse_periph.h"
+#include "bootloader_random.h"
+#include "sys/param.h"
+
+const static char *TAG = "efuse";
+
+// Contains functions that provide access to efuse fields which are often used in IDF.
+
+// Returns chip version from efuse
+uint8_t esp_efuse_get_chip_ver(void)
+{
+    // should return the same value as bootloader_common_get_chip_revision()
+    uint32_t chip_ver = 0;
+    // TODO: ESP32S2 does not have this field
+    return chip_ver;
+}
+
+// Returns chip package from efuse
+uint32_t esp_efuse_get_pkg_ver(void)
+{
+    uint32_t pkg_ver = 0;
+    esp_efuse_read_field_blob(ESP_EFUSE_PKG_VERSION, &pkg_ver, 4);
+    return pkg_ver;
+}
+
+void esp_efuse_write_random_key(uint32_t blk_wdata0_reg)
+{
+    uint32_t buf[8];
+    uint8_t raw[24];
+
+    bootloader_fill_random(buf, sizeof(buf));
+
+    ESP_LOGV(TAG, "Writing random values to address 0x%08x", blk_wdata0_reg);
+    for (int i = 0; i < 8; i++) {
+        ESP_LOGV(TAG, "EFUSE_BLKx_WDATA%d_REG = 0x%08x", i, buf[i]);
+        REG_WRITE(blk_wdata0_reg + 4*i, buf[i]);
+    }
+    bzero(buf, sizeof(buf));
+    bzero(raw, sizeof(raw));
+}
+
+esp_err_t esp_efuse_disable_rom_download_mode(void)
+{
+    return esp_efuse_write_field_bit(ESP_EFUSE_DIS_DOWNLOAD_MODE);
+}
+
+esp_err_t esp_efuse_enable_rom_secure_download_mode(void)
+{
+    if (esp_efuse_read_field_bit(ESP_EFUSE_DIS_DOWNLOAD_MODE)) {
+        return ESP_ERR_INVALID_STATE;
+    }
+    return esp_efuse_write_field_bit(ESP_EFUSE_ENABLE_SECURITY_DOWNLOAD);
+}