espressif: Add ESP32-C3 initial basic support

ESP32-C3 target added to the Espressif port, CMakeLists, and
added related files to ESP32-C3 target directory as well.

Signed-off-by: Almir Okato <almir.okato@espressif.com>
diff --git a/boot/espressif/CMakeLists.txt b/boot/espressif/CMakeLists.txt
index bbdab33..48c5950 100644
--- a/boot/espressif/CMakeLists.txt
+++ b/boot/espressif/CMakeLists.txt
@@ -8,6 +8,13 @@
 
 add_definitions(-DMCUBOOT_TARGET=${MCUBOOT_TARGET})
 
+if ("${MCUBOOT_TARGET}" STREQUAL "esp32" OR
+    "${MCUBOOT_TARGET}" STREQUAL "esp32s2")
+    set(MCUBOOT_ARCH "xtensa")
+elseif("${MCUBOOT_TARGET}" STREQUAL "esp32c3")
+    set(MCUBOOT_ARCH "riscv")
+endif()
+
 if (NOT DEFINED IDF_PATH)
     if (EXISTS "${CMAKE_CURRENT_LIST_DIR}/hal/esp-idf")
         set(IDF_PATH "${CMAKE_CURRENT_LIST_DIR}/hal/esp-idf")
@@ -90,7 +97,6 @@
     )
 
 set(CFLAGS
-    "-mlongcalls"
     "-Wno-frame-address"
     "-Wall"
     "-Wextra"
@@ -120,7 +126,6 @@
 
 set(LDFLAGS
     "-nostdlib"
-    "-mlongcalls"
     "-Wno-frame-address"
     "-Wl,--cref"
     "-Wl,--Map=${APP_NAME}.map"
@@ -133,6 +138,15 @@
     "-lgcov"
     )
 
+if ("${MCUBOOT_ARCH}" STREQUAL "xtensa")
+    list(APPEND CFLAGS
+        "-mlongcalls"
+        )
+    list(APPEND LDFLAGS
+        "-mlongcalls"
+        )
+endif()
+
 add_subdirectory(hal)
 add_executable(
     ${APP_EXECUTABLE}
diff --git a/boot/espressif/hal/CMakeLists.txt b/boot/espressif/hal/CMakeLists.txt
index db82d83..f84abc9 100644
--- a/boot/espressif/hal/CMakeLists.txt
+++ b/boot/espressif/hal/CMakeLists.txt
@@ -11,13 +11,12 @@
     )
 
 list(APPEND INCLUDE_DIRS
+    ${esp_idf_dir}/components/${MCUBOOT_ARCH}/include
     ${esp_idf_dir}/components/esp_common/include
     ${esp_idf_dir}/components/esp_rom/include
     ${esp_idf_dir}/components/esp_rom/include/${MCUBOOT_TARGET}
-    ${esp_idf_dir}/components/xtensa/${MCUBOOT_TARGET}/include
     ${esp_idf_dir}/components/spi_flash/include
     ${esp_idf_dir}/components/spi_flash/private_include
-    ${esp_idf_dir}/components/xtensa/include
     ${esp_idf_dir}/components/soc/${MCUBOOT_TARGET}/include
     ${esp_idf_dir}/components/${MCUBOOT_TARGET}/include
     ${esp_idf_dir}/components/soc/include
@@ -32,6 +31,13 @@
     ${esp_idf_dir}/components/efuse/include
     ${esp_idf_dir}/components/efuse/${MCUBOOT_TARGET}/include
     )
+
+if("${MCUBOOT_ARCH}" STREQUAL "xtensa")
+    list(APPEND INCLUDE_DIRS
+        ${esp_idf_dir}/components/${MCUBOOT_ARCH}/${MCUBOOT_TARGET}/include
+        )
+endif()
+
 set(hal_srcs
     ${SRC_DIR}/bootloader_wdt.c
     ${SRC_DIR}/${MCUBOOT_TARGET}/bootloader_init.c
@@ -53,15 +59,8 @@
     ${esp_idf_dir}/components/${MCUBOOT_TARGET}/clk.c
     )
 
-if ("${MCUBOOT_TARGET}" STREQUAL "esp32s2")
-    list(APPEND hal_srcs
-        ${esp_idf_dir}/components/esp_hw_support/port/${MCUBOOT_TARGET}/regi2c_ctrl.c
-    )
-endif()
-
 set(CFLAGS
     "-nostdlib"
-    "-mlongcalls"
     "-Wno-frame-address"
     "-Wall"
     "-Wextra"
@@ -88,7 +87,6 @@
     )
 
 set(LDFLAGS
-    "-mlongcalls"
     "-Wno-frame-address"
     "-Wl,--cref"
     "-Wl,--Map=${APP_NAME}.map"
@@ -101,7 +99,14 @@
     "-lgcov"
     )
 
-add_library(hal STATIC ${hal_srcs} ${INCLUDE_DIRS})
+if (("${MCUBOOT_TARGET}" STREQUAL "xtensa"))
+    list(APPEND CFLAGS
+        "-mlongcalls"
+        )
+    list(APPEND LDFLAGS
+        "-mlongcalls"
+        )
+endif()
 
 set_source_files_properties(
     ${esp_idf_dir}/components/bootloader_support/src/bootloader_flash.c
@@ -110,7 +115,19 @@
     ${esp_idf_dir}/components/esp_hw_support/port/${MCUBOOT_TARGET}/rtc_clk.c
     ${esp_idf_dir}/components/esp_hw_support/port/${MCUBOOT_TARGET}/rtc_time.c
     PROPERTIES COMPILE_FLAGS
-    "-Wno-unused-variable")
+    "-Wno-unused-variable"
+    )
+
+set(LINKER_SCRIPTS
+    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.ld
+    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.libgcc.ld
+    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.api.ld
+    -T${esp_idf_dir}/components/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.peripherals.ld
+    )
+
+include(${CMAKE_CURRENT_LIST_DIR}/include/${MCUBOOT_TARGET}/${MCUBOOT_TARGET}.cmake)
+
+add_library(hal STATIC ${hal_srcs} ${INCLUDE_DIRS})
 
 target_include_directories(
     hal
@@ -124,20 +141,6 @@
     ${CFLAGS}
     )
 
-set(LINKER_SCRIPTS
-    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.ld
-    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.libgcc.ld
-    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.api.ld
-    -T${esp_idf_dir}/components/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.peripherals.ld
-    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.newlib-funcs.ld
-    )
-
-if ("${MCUBOOT_TARGET}" STREQUAL "esp32s2")
-    list(APPEND LINKER_SCRIPTS
-        -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.spiflash.ld
-    )
-endif()
-
 target_link_libraries(
     hal
     PUBLIC
diff --git a/boot/espressif/hal/include/esp32/esp32.cmake b/boot/espressif/hal/include/esp32/esp32.cmake
new file mode 100644
index 0000000..ab96d1d
--- /dev/null
+++ b/boot/espressif/hal/include/esp32/esp32.cmake
@@ -0,0 +1,3 @@
+list(APPEND LINKER_SCRIPTS
+    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.newlib-funcs.ld
+    )
diff --git a/boot/espressif/hal/include/esp32c3/esp32c3.cmake b/boot/espressif/hal/include/esp32c3/esp32c3.cmake
new file mode 100644
index 0000000..372f4a4
--- /dev/null
+++ b/boot/espressif/hal/include/esp32c3/esp32c3.cmake
@@ -0,0 +1,13 @@
+list(APPEND hal_srcs
+    ${esp_idf_dir}/components/bootloader_support/src/flash_qio_mode.c
+    ${esp_idf_dir}/components/esp_hw_support/port/${MCUBOOT_TARGET}/cpu_util_esp32c3.c
+)
+
+list(APPEND LINKER_SCRIPTS
+    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.newlib.ld
+)
+
+set_source_files_properties(
+    ${esp_idf_dir}/components/bootloader_support/src/flash_qio_mode.c
+    PROPERTIES COMPILE_FLAGS
+    "-Wno-unused-variable")
diff --git a/boot/espressif/hal/include/esp32c3/sdkconfig.h b/boot/espressif/hal/include/esp32c3/sdkconfig.h
new file mode 100644
index 0000000..06f60ae
--- /dev/null
+++ b/boot/espressif/hal/include/esp32c3/sdkconfig.h
@@ -0,0 +1,9 @@
+#define CONFIG_IDF_TARGET_ESP32C3 1
+#define CONFIG_IDF_TARGET_ARCH_RISCV 1
+#define CONFIG_SPI_FLASH_ROM_DRIVER_PATCH 1
+#define CONFIG_MCUBOOT 1
+#define NDEBUG 1
+#define CONFIG_BOOTLOADER_WDT_TIME_MS 9000
+#define CONFIG_ESP_CONSOLE_UART_BAUDRATE 115200
+#define CONFIG_BOOTLOADER_OFFSET_IN_FLASH 0x0000
+#define BOOTLOADER_BUILD 1
diff --git a/boot/espressif/hal/include/esp32s2/esp32s2.cmake b/boot/espressif/hal/include/esp32s2/esp32s2.cmake
new file mode 100644
index 0000000..171ab9d
--- /dev/null
+++ b/boot/espressif/hal/include/esp32s2/esp32s2.cmake
@@ -0,0 +1,8 @@
+list(APPEND hal_srcs
+    ${esp_idf_dir}/components/esp_hw_support/port/${MCUBOOT_TARGET}/regi2c_ctrl.c
+    )
+
+list(APPEND LINKER_SCRIPTS
+    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.newlib-funcs.ld
+    -T${esp_idf_dir}/components/esp_rom/${MCUBOOT_TARGET}/ld/${MCUBOOT_TARGET}.rom.spiflash.ld
+    )
diff --git a/boot/espressif/hal/include/mcuboot_config/mcuboot_assert.h b/boot/espressif/hal/include/mcuboot_config/mcuboot_assert.h
index aaad1a3..fc59909 100644
--- a/boot/espressif/hal/include/mcuboot_config/mcuboot_assert.h
+++ b/boot/espressif/hal/include/mcuboot_config/mcuboot_assert.h
@@ -7,6 +7,10 @@
 #pragma once
 
 extern void mcuboot_assert_handler(const char *file, int line, const char *func);
+
+#ifdef assert
+#undef assert
+#endif
 #define assert(arg)                                                 \
     do {                                                            \
         if (!(arg)) {                                               \
diff --git a/boot/espressif/hal/include/mcuboot_config/mcuboot_logging.h b/boot/espressif/hal/include/mcuboot_config/mcuboot_logging.h
index 2c69a14..f6a16a2 100644
--- a/boot/espressif/hal/include/mcuboot_config/mcuboot_logging.h
+++ b/boot/espressif/hal/include/mcuboot_config/mcuboot_logging.h
@@ -20,6 +20,8 @@
 #define TARGET "[esp32]"
 #elif CONFIG_IDF_TARGET_ESP32S2
 #define TARGET "[esp32s2]"
+#elif CONFIG_IDF_TARGET_ESP32C3
+#define TARGET "[esp32c3]"
 #else
 #error "Selected target not supported."
 #endif
diff --git a/boot/espressif/hal/src/esp32c3/bootloader_init.c b/boot/espressif/hal/src/esp32c3/bootloader_init.c
new file mode 100644
index 0000000..6ec064b
--- /dev/null
+++ b/boot/espressif/hal/src/esp32c3/bootloader_init.c
@@ -0,0 +1,246 @@
+/*
+ * Copyright (c) 2021 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+
+#include "sdkconfig.h"
+#include "esp_attr.h"
+#include "esp_image_format.h"
+
+#include "esp_rom_efuse.h"
+#include "esp_rom_gpio.h"
+#include "esp_rom_uart.h"
+#include "esp_rom_sys.h"
+
+#include "bootloader_init.h"
+#include "bootloader_clock.h"
+#include "bootloader_flash_config.h"
+#include "bootloader_mem.h"
+#include "bootloader_flash.h"
+#include "bootloader_flash_priv.h"
+#include "regi2c_ctrl.h"
+
+#include "soc/extmem_reg.h"
+#include "soc/io_mux_reg.h"
+#include "soc/efuse_reg.h"
+#include "soc/rtc.h"
+
+#include "rom/cache.h"
+#include "rom/ets_sys.h"
+#include "rom/spi_flash.h"
+#include "rom/uart.h"
+#include "rom/efuse.h"
+
+#include "hal/wdt_hal.h"
+
+extern uint8_t bootloader_common_get_chip_revision(void);
+
+esp_image_header_t WORD_ALIGNED_ATTR bootloader_image_hdr;
+
+void bootloader_clear_bss_section(void)
+{
+    memset(&_bss_start, 0, (&_bss_end - &_bss_start) * sizeof(_bss_start));
+}
+
+void IRAM_ATTR bootloader_configure_spi_pins(int drv)
+{
+    const uint32_t spiconfig = esp_rom_efuse_get_flash_gpio_info();
+    uint8_t wp_pin = esp_rom_efuse_get_flash_wp_gpio();
+    uint8_t clk_gpio_num = SPI_CLK_GPIO_NUM;
+    uint8_t q_gpio_num   = SPI_Q_GPIO_NUM;
+    uint8_t d_gpio_num   = SPI_D_GPIO_NUM;
+    uint8_t cs0_gpio_num = SPI_CS0_GPIO_NUM;
+    uint8_t hd_gpio_num  = SPI_HD_GPIO_NUM;
+    uint8_t wp_gpio_num  = SPI_WP_GPIO_NUM;
+    if (spiconfig != 0) {
+        clk_gpio_num = spiconfig         & 0x3f;
+        q_gpio_num = (spiconfig >> 6)    & 0x3f;
+        d_gpio_num = (spiconfig >> 12)   & 0x3f;
+        cs0_gpio_num = (spiconfig >> 18) & 0x3f;
+        hd_gpio_num = (spiconfig >> 24)  & 0x3f;
+        wp_gpio_num = wp_pin;
+    }
+    esp_rom_gpio_pad_set_drv(clk_gpio_num, drv);
+    esp_rom_gpio_pad_set_drv(q_gpio_num,   drv);
+    esp_rom_gpio_pad_set_drv(d_gpio_num,   drv);
+    esp_rom_gpio_pad_set_drv(cs0_gpio_num, drv);
+    if (hd_gpio_num <= MAX_PAD_GPIO_NUM) {
+        esp_rom_gpio_pad_set_drv(hd_gpio_num, drv);
+    }
+    if (wp_gpio_num <= MAX_PAD_GPIO_NUM) {
+        esp_rom_gpio_pad_set_drv(wp_gpio_num, drv);
+    }
+}
+
+static void bootloader_reset_mmu(void)
+{
+    Cache_Suspend_ICache();
+    Cache_Invalidate_ICache_All();
+    Cache_MMU_Init();
+
+    REG_CLR_BIT(EXTMEM_ICACHE_CTRL1_REG, EXTMEM_ICACHE_SHUT_IBUS);
+    REG_CLR_BIT(EXTMEM_ICACHE_CTRL1_REG, EXTMEM_ICACHE_SHUT_DBUS);
+}
+
+esp_err_t bootloader_read_bootloader_header(void)
+{
+    if (bootloader_flash_read(ESP_BOOTLOADER_OFFSET, &bootloader_image_hdr, sizeof(esp_image_header_t), true) != ESP_OK) {
+        return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+static void update_flash_config(const esp_image_header_t *bootloader_hdr)
+{
+    uint32_t size;
+    switch (bootloader_hdr->spi_size) {
+    case ESP_IMAGE_FLASH_SIZE_1MB:
+        size = 1;
+        break;
+    case ESP_IMAGE_FLASH_SIZE_2MB:
+        size = 2;
+        break;
+    case ESP_IMAGE_FLASH_SIZE_4MB:
+        size = 4;
+        break;
+    case ESP_IMAGE_FLASH_SIZE_8MB:
+        size = 8;
+        break;
+    case ESP_IMAGE_FLASH_SIZE_16MB:
+        size = 16;
+        break;
+    default:
+        size = 2;
+    }
+    uint32_t autoload = Cache_Suspend_ICache();
+    // Set flash chip size
+    esp_rom_spiflash_config_param(rom_spiflash_legacy_data->chip.device_id, size * 0x100000, 0x10000, 0x1000, 0x100, 0xffff);
+    Cache_Resume_ICache(autoload);
+}
+
+static void IRAM_ATTR bootloader_init_flash_configure(void)
+{
+    bootloader_flash_dummy_config(&bootloader_image_hdr);
+    bootloader_flash_cs_timing_config();
+}
+
+static void bootloader_spi_flash_resume(void)
+{
+    bootloader_execute_flash_command(CMD_RESUME, 0, 0, 0);
+    esp_rom_spiflash_wait_idle(&g_rom_flashchip);
+}
+
+static esp_err_t bootloader_init_spi_flash(void)
+{
+    bootloader_init_flash_configure();
+    bootloader_spi_flash_resume();
+    esp_rom_spiflash_unlock();
+    update_flash_config(&bootloader_image_hdr);
+
+    return ESP_OK;
+}
+
+static inline void bootloader_hardware_init(void)
+{
+    // This check is always included in the bootloader so it can
+    // print the minimum revision error message later in the boot
+    if (bootloader_common_get_chip_revision() < 3) {
+        REGI2C_WRITE_MASK(I2C_ULP, I2C_ULP_IR_FORCE_XPD_IPH, 1);
+        REGI2C_WRITE_MASK(I2C_BIAS, I2C_BIAS_DREG_1P1_PVT, 12);
+    }
+}
+
+static inline void bootloader_glitch_reset_disable(void)
+{
+    /*
+      For origin chip & ECO1: only support swt reset;
+      For ECO2: fix brownout reset bug, support swt & brownout reset;
+      For ECO3: fix clock glitch reset bug, support all reset, include: swt & brownout & clock glitch reset.
+    */
+    uint8_t chip_version = bootloader_common_get_chip_revision();
+    if (chip_version < 2) {
+        REG_SET_FIELD(RTC_CNTL_FIB_SEL_REG, RTC_CNTL_FIB_SEL, RTC_CNTL_FIB_SUPER_WDT_RST);
+    } else if (chip_version == 2) {
+        REG_SET_FIELD(RTC_CNTL_FIB_SEL_REG, RTC_CNTL_FIB_SEL, RTC_CNTL_FIB_SUPER_WDT_RST | RTC_CNTL_FIB_BOR_RST);
+    }
+}
+
+static void bootloader_super_wdt_auto_feed(void)
+{
+    REG_WRITE(RTC_CNTL_SWD_WPROTECT_REG, RTC_CNTL_SWD_WKEY_VALUE);
+    REG_SET_BIT(RTC_CNTL_SWD_CONF_REG, RTC_CNTL_SWD_AUTO_FEED_EN);
+    REG_WRITE(RTC_CNTL_SWD_WPROTECT_REG, 0);
+}
+
+void bootloader_config_wdt(void)
+{
+    wdt_hal_context_t rtc_wdt_ctx = {.inst = WDT_RWDT, .rwdt_dev = &RTCCNTL};
+    wdt_hal_write_protect_disable(&rtc_wdt_ctx);
+    wdt_hal_set_flashboot_en(&rtc_wdt_ctx, false);
+    wdt_hal_write_protect_enable(&rtc_wdt_ctx);
+
+#ifdef CONFIG_ESP_MCUBOOT_WDT_ENABLE
+    wdt_hal_init(&rtc_wdt_ctx, WDT_RWDT, 0, false);
+    uint32_t stage_timeout_ticks = (uint32_t)((uint64_t)CONFIG_BOOTLOADER_WDT_TIME_MS * rtc_clk_slow_freq_get_hz() / 1000);
+    wdt_hal_write_protect_disable(&rtc_wdt_ctx);
+    wdt_hal_config_stage(&rtc_wdt_ctx, WDT_STAGE0, stage_timeout_ticks, WDT_STAGE_ACTION_RESET_RTC);
+    wdt_hal_enable(&rtc_wdt_ctx);
+    wdt_hal_write_protect_enable(&rtc_wdt_ctx);
+#endif
+
+    wdt_hal_context_t wdt_ctx = {.inst = WDT_MWDT0, .mwdt_dev = &TIMERG0};
+    wdt_hal_write_protect_disable(&wdt_ctx);
+    wdt_hal_set_flashboot_en(&wdt_ctx, false);
+    wdt_hal_write_protect_enable(&wdt_ctx);
+}
+
+static void bootloader_init_uart_console(void)
+{
+    const int uart_num = 0;
+
+    esp_rom_install_uart_printf();
+    esp_rom_uart_tx_wait_idle(0);
+    uint32_t clock_hz = UART_CLK_FREQ_ROM;
+    esp_rom_uart_set_clock_baudrate(uart_num, clock_hz, CONFIG_ESP_CONSOLE_UART_BAUDRATE);
+}
+
+esp_err_t bootloader_init(void)
+{
+    esp_err_t ret = ESP_OK;
+
+    bootloader_hardware_init();
+    bootloader_glitch_reset_disable();
+    bootloader_super_wdt_auto_feed();
+    // protect memory region
+    bootloader_init_mem();
+    /* check that static RAM is after the stack */
+    assert(&_bss_start <= &_bss_end);
+    assert(&_data_start <= &_data_end);
+    // clear bss section
+    bootloader_clear_bss_section();
+    // reset MMU
+    bootloader_reset_mmu();
+    // config clock
+    bootloader_clock_configure();
+    /* initialize uart console, from now on, we can use ets_printf */
+    bootloader_init_uart_console();
+    // update flash ID
+    bootloader_flash_update_id();
+    // read bootloader header
+    if ((ret = bootloader_read_bootloader_header()) != ESP_OK) {
+        goto err;
+    }
+    // initialize spi flash
+    if ((ret = bootloader_init_spi_flash()) != ESP_OK) {
+        goto err;
+    }
+    // config WDT
+    bootloader_config_wdt();
+err:
+    return ret;
+}
diff --git a/boot/espressif/port/esp32c3/ld/bootloader.ld b/boot/espressif/port/esp32c3/ld/bootloader.ld
new file mode 100644
index 0000000..d00ad60
--- /dev/null
+++ b/boot/espressif/port/esp32c3/ld/bootloader.ld
@@ -0,0 +1,141 @@
+/*
+ * Linker file used to link the bootloader.
+ */
+
+MEMORY
+{
+  iram_seg (RWX) :    org = 0x403CA000, len = 0x6000
+  iram_loader_seg (RWX) : org = 0x403D0000, len = 0x2000
+  dram_seg (RW) :     org = 0x3FCD6000, len = 0x6000
+}
+
+/*  Default entry point:  */
+ENTRY(main);
+
+
+SECTIONS
+{
+
+  .iram_loader.text :
+  {
+    . = ALIGN (16);
+    _loader_text_start = ABSOLUTE(.);
+    *(.stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
+    *(.iram1 .iram1.*) /* catch stray IRAM_ATTR */
+    *libhal.a:bootloader_flash.*(.literal .text .literal.* .text.*)
+    *libhal.a:bootloader_flash_config_esp32c3.*(.literal .text .literal.* .text.*)
+    *esp_mcuboot.*(.literal .text .literal.* .text.*)
+    *esp_loader.*(.literal .text .literal.* .text.*)
+    *(.fini.literal)
+    *(.fini)
+    *(.gnu.version)
+    _loader_text_end = ABSOLUTE(.);
+  } > iram_loader_seg
+
+  .iram.text :
+  {
+    . = ALIGN (16);
+    *(.entry.text)
+    *(.init.literal)
+    *(.init)
+  } > iram_seg
+
+
+  /* Shared RAM */
+  .dram0.bss (NOLOAD) :
+  {
+    . = ALIGN (8);
+    _dram_start = ABSOLUTE(.);
+    _bss_start = ABSOLUTE(.);
+    *(.dynsbss)
+    *(.sbss)
+    *(.sbss.*)
+    *(.gnu.linkonce.sb.*)
+    *(.scommon)
+    *(.sbss2)
+    *(.sbss2.*)
+    *(.gnu.linkonce.sb2.*)
+    *(.dynbss)
+    *(.bss)
+    *(.bss.*)
+    *(.gnu.linkonce.b.*)
+    *(COMMON)
+    . = ALIGN (8);
+    _bss_end = ABSOLUTE(.);
+  } >dram_seg
+
+  .dram0.data :
+  {
+    _data_start = ABSOLUTE(.);
+    *(.data)
+    *(.data.*)
+    *(.gnu.linkonce.d.*)
+    *(.data1)
+    *(.sdata)
+    *(.sdata.*)
+    *(.gnu.linkonce.s.*)
+    *(.sdata2)
+    *(.sdata2.*)
+    *(.gnu.linkonce.s2.*)
+    *(.jcr)
+    _data_end = ABSOLUTE(.);
+  } >dram_seg
+
+  .dram0.rodata :
+  {
+    _rodata_start = ABSOLUTE(.);
+    *(.rodata)
+    *(.rodata.*)
+    *(.gnu.linkonce.r.*)
+    *(.rodata1)
+    __XT_EXCEPTION_TABLE_ = ABSOLUTE(.);
+    *(.xt_except_table)
+    *(.gcc_except_table)
+    *(.gnu.linkonce.e.*)
+    *(.gnu.version_r)
+    *(.eh_frame)
+    . = (. + 3) & ~ 3;
+    /*  C++ constructor and destructor tables, properly ordered:  */
+    __init_array_start = ABSOLUTE(.);
+    KEEP (*crtbegin.*(.ctors))
+    KEEP (*(EXCLUDE_FILE (*crtend.*) .ctors))
+    KEEP (*(SORT(.ctors.*)))
+    KEEP (*(.ctors))
+    __init_array_end = ABSOLUTE(.);
+    KEEP (*crtbegin.*(.dtors))
+    KEEP (*(EXCLUDE_FILE (*crtend.*) .dtors))
+    KEEP (*(SORT(.dtors.*)))
+    KEEP (*(.dtors))
+    /*  C++ exception handlers table:  */
+    __XT_EXCEPTION_DESCS_ = ABSOLUTE(.);
+    *(.xt_except_desc)
+    *(.gnu.linkonce.h.*)
+    __XT_EXCEPTION_DESCS_END__ = ABSOLUTE(.);
+    *(.xt_except_desc_end)
+    *(.dynamic)
+    *(.gnu.version_d)
+    _rodata_end = ABSOLUTE(.);
+    /* Literals are also RO data. */
+    _lit4_start = ABSOLUTE(.);
+    *(*.lit4)
+    *(.lit4.*)
+    *(.gnu.linkonce.lit4.*)
+    _lit4_end = ABSOLUTE(.);
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+    _dram_end = ABSOLUTE(.);
+  } >dram_seg
+
+  .iram.text :
+  {
+    _stext = .;
+    _text_start = ABSOLUTE(.);
+    *(.literal .text .literal.* .text.* .stub .gnu.warning .gnu.linkonce.literal.* .gnu.linkonce.t.*.literal .gnu.linkonce.t.*)
+    *(.iram .iram.*) /* catch stray IRAM_ATTR */
+    *(.fini.literal)
+    *(.fini)
+    *(.gnu.version)
+    _text_end = ABSOLUTE(.);
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+}
diff --git a/boot/espressif/port/esp_loader.c b/boot/espressif/port/esp_loader.c
index 932f2c0..6e8d2cb 100644
--- a/boot/espressif/port/esp_loader.c
+++ b/boot/espressif/port/esp_loader.c
@@ -6,11 +6,14 @@
 
 #include <string.h>
 #include <soc/soc.h>
-#include <soc/dport_reg.h>
 #include "soc/soc_memory_layout.h"
 #include <bootloader_flash.h>
 #include <bootloader_flash_priv.h>
 
+#if defined(CONFIG_IDF_TARGET_ESP32) || defined(CONFIG_IDF_TARGET_ESP32S2)
+#include <soc/dport_reg.h>
+#endif
+
 #include "rom/cache.h"
 #include "rom/efuse.h"
 #include "rom/ets_sys.h"
@@ -87,7 +90,7 @@
     }
 
     if (!esp_ptr_in_iram((void *)load_header.entry_addr)) {
-        MCUBOOT_LOG_ERR("Application entry point is not in IRAM. Aborting");
+        MCUBOOT_LOG_ERR("Application entry point (0x%x) is not in IRAM. Aborting", load_header.entry_addr);
         FIH_PANIC;
     }
 
diff --git a/boot/espressif/tools/toolchain-esp32c3.cmake b/boot/espressif/tools/toolchain-esp32c3.cmake
new file mode 100644
index 0000000..cd30a2a
--- /dev/null
+++ b/boot/espressif/tools/toolchain-esp32c3.cmake
@@ -0,0 +1,9 @@
+set(CMAKE_SYSTEM_NAME Generic)
+
+set(CMAKE_C_COMPILER riscv32-esp-elf-gcc)
+set(CMAKE_CXX_COMPILER riscv32-esp-elf-g++)
+set(CMAKE_ASM_COMPILER riscv32-esp-elf-gcc)
+
+set(CMAKE_C_FLAGS "-march=rv32imc" CACHE STRING "C Compiler Base Flags")
+set(CMAKE_CXX_FLAGS "-march=rv32imc" CACHE STRING "C++ Compiler Base Flags")
+set(CMAKE_EXE_LINKER_FLAGS "-nostartfiles -march=rv32imc --specs=nosys.specs" CACHE STRING "Linker Base Flags")