diff --git a/cpu/esp32/Kconfig b/cpu/esp32/Kconfig
index 1847aae904..544e2dd412 100644
--- a/cpu/esp32/Kconfig
+++ b/cpu/esp32/Kconfig
@@ -1,5 +1,5 @@
 # Copyright (c) 2020 HAW Hamburg
-#               2021 Gunar Schorcht
+#               2022 Gunar Schorcht
 #
 # This file is subject to the terms and conditions of the GNU Lesser
 # General Public License v2.1. See the file LICENSE in the top level
@@ -20,17 +20,12 @@ config CPU_FAM_ESP32
     select HAS_PUF_SRAM
 
     select PACKAGE_ESP32_SDK if TEST_KCONFIG
-    select PACKAGE_ESP32_SDK_LIBS if TEST_KCONFIG
 
-    select MODULE_ESP_IDF_DRIVER if TEST_KCONFIG
-    select MODULE_ESP_IDF_ESP32 if TEST_KCONFIG
-    select MODULE_ESP_IDF_SOC if TEST_KCONFIG
-
-    select MODULE_PERIPH_RTT if HAS_PERIPH_RTT && MODULE_PM_LAYERED
-    select MODULE_RTT_RTC if HAS_PERIPH_RTT && MODULE_PERIPH_RTC
-    select MODULE_PS if MODULE_SHELL
-    select MODULE_PTHREAD if MODULE_CPP && TEST_KCONFIG
     select MODULE_LIBC_GETTIMEOFDAY if TEST_KCONFIG
+    select MODULE_RTT_RTC if HAS_PERIPH_RTT && MODULE_PERIPH_RTC
+    select MODULE_PERIPH_RTT if HAS_PERIPH_RTT && MODULE_PM_LAYERED
+    select MODULE_PS if MODULE_SHELL
+    select MODULE_PTHREAD if MODULE_CPP
     imply MODULE_NEWLIB_NANO
 
 ## CPU Models
@@ -125,7 +120,11 @@ menu "ESP32 specific configurations"
     config MODULE_ESP_SPI_RAM
         bool "SPI RAM support"
         depends on HAS_ESP_SPI_RAM
+        select MODULE_ESP_IDF_EFUSE
+        select MODULE_ESP_IDF_GPIO
         select MODULE_ESP_IDF_HEAP
+        select MODULE_ESP_IDF_SPI_FLASH
+        select MODULE_ESP_IDF_SPI_RAM
         help
             Say y to use external SPI RAM connected through the FSPI interface.
 
@@ -135,6 +134,7 @@ menu "ESP32 specific configurations"
 
 endmenu
 
+rsource "bootloader/Kconfig"
+rsource "esp-idf/Kconfig"
 rsource "periph/Kconfig"
-rsource "vendor/esp-idf/Kconfig"
 source "$(RIOTCPU)/esp_common/Kconfig"
diff --git a/cpu/esp32/Makefile b/cpu/esp32/Makefile
index 95ea5c48bf..621be88e25 100644
--- a/cpu/esp32/Makefile
+++ b/cpu/esp32/Makefile
@@ -6,7 +6,11 @@ SRC = irq_arch.c startup.c syscalls.c
 # Add a list of subdirectories, that should also be built:
 DIRS += $(RIOTCPU)/esp_common
 DIRS += periph
-DIRS += vendor
+DIRS += esp-idf
+
+ifneq (, $(filter esp_bootloader, $(USEMODULE)))
+    DIRS += bootloader
+endif
 
 ifneq (, $(filter esp_eth, $(USEMODULE)))
     DIRS += esp-eth
diff --git a/cpu/esp32/Makefile.dep b/cpu/esp32/Makefile.dep
index 6c01c61ae5..bb96004bc3 100644
--- a/cpu/esp32/Makefile.dep
+++ b/cpu/esp32/Makefile.dep
@@ -3,11 +3,9 @@
 include $(RIOTCPU)/esp_common/Makefile.dep
 
 USEPKG += esp32_sdk
-USEPKG += esp32_sdk_libs
 
-USEMODULE += esp_idf_driver
-USEMODULE += esp_idf_esp32
-USEMODULE += esp_idf_soc
+USEMODULE += esp_idf_common
+USEMODULE += esp_bootloader
 
 ifneq (,$(filter newlib,$(USEMODULE)))
   DEFAULT_MODULE += newlib_nano
@@ -18,28 +16,38 @@ ifneq (,$(filter cpp,$(USEMODULE)))
 endif
 
 ifneq (,$(filter esp_eth,$(USEMODULE)))
-  USEMODULE += esp_freertos
+  USEMODULE += esp_idf_efuse
   USEMODULE += esp_idf_eth
-  USEMODULE += esp_idf_eth_phy
+  USEMODULE += esp_idf_event
+  USEMODULE += esp_idf_gpio
+  USEMODULE += esp_idf_spi_flash
   USEMODULE += netdev_eth
   USEMODULE += netopt
   USEMODULE += ztimer_msec
 endif
 
 ifneq (,$(filter esp_wifi_any,$(USEMODULE)))
-  # add additional modules used for any WiFi interface
-  USEMODULE += esp_freertos
+  # add additional modules and packages used for any WiFi interface
+  USEPKG += esp32_sdk_lib_phy
+  USEPKG += esp32_sdk_lib_wifi
+  USEMODULE += esp_idf_efuse
+  USEMODULE += esp_idf_event
   USEMODULE += esp_idf_heap
   USEMODULE += esp_idf_nvs_flash
-  USEMODULE += esp_idf_wpa_supplicant_crypto
-  USEMODULE += esp_idf_wpa_supplicant_port
+  USEMODULE += esp_idf_spi_flash
+  USEMODULE += esp_idf_wifi
+  USEMODULE += esp_idf_wpa_supplicant
+  USEMODULE += pthread
 endif
 
-ifneq (,$(filter esp_wifi_enterprise,$(USEMODULE)))
-  # add additional modules used for WPA2 Enterprise mode
-  USEMODULE += esp_idf_wpa_supplicant_wpa2_eap_peer
-  USEMODULE += esp_idf_wpa_supplicant_wpa2_tls
-  USEMODULE += esp_idf_wpa_supplicant_wpa2_utils
+ifneq (,$(filter esp_idf_heap,$(USEMODULE)))
+  # The ESP-IDF heap component uses the TLSF implementation that is part of
+  # the component. To avoid conflicts with modules and packages that use the
+  # RIOT package `tlsf`, this package is also used for the ESP-IDF heap instead
+  # of its own implementation. There does not seem to be any differences in
+  # the implementations of TLSF with the exception of heap poisoning, which
+  # is not configured.
+  USEPKG += tlsf
 endif
 
 ifneq (,$(filter esp_idf_nvs_flash,$(USEMODULE)))
@@ -74,13 +82,13 @@ ifneq (,$(filter periph_i2c,$(USEMODULE)))
   endif
 endif
 
-ifneq (,$(filter esp_now esp_wifi esp_spi_ram,$(USEMODULE)))
-  # the ESP-IDF heap has to be used if SPI RAM is used
-  USEMODULE += esp_idf_heap
-endif
-
 ifneq (,$(filter esp_spi_ram,$(USEMODULE)))
   FEATURES_REQUIRED += esp_spi_ram
+  USEMODULE += esp_idf_efuse
+  USEMODULE += esp_idf_gpio
+  USEMODULE += esp_idf_heap
+  USEMODULE += esp_idf_spi_flash
+  USEMODULE += esp_idf_spi_ram
 endif
 
 ifneq (,$(filter mtd,$(USEMODULE)))
diff --git a/cpu/esp32/Makefile.include b/cpu/esp32/Makefile.include
index 30298e68b7..3d0bff55e0 100644
--- a/cpu/esp32/Makefile.include
+++ b/cpu/esp32/Makefile.include
@@ -1,5 +1,5 @@
 # ESP32 specific flashing options
-FLASH_CHIP  = esp32
+FLASH_CHIP  = $(CPU)
 FLASH_MODE ?= dout
 FLASH_FREQ  = 40m   # DO NOT CHANGE
 FLASH_SIZE ?= 4
@@ -11,9 +11,12 @@ include $(RIOTCPU)/esp_common/Makefile.include
 
 # regular Makefile
 
-TARGET_ARCH_ESP32 ?= xtensa-esp32-elf
-TARGET_ARCH ?= $(TARGET_ARCH_ESP32)
+TARGET_ARCH_$(CPU) ?= xtensa-$(CPU)-elf
+TARGET_ARCH ?= $(TARGET_ARCH_$(CPU))
 
+CPU_UC = $(shell echo '$(CPU)' | tr '[:lower:]' '[:upper:]')
+
+PSEUDOMODULES += esp_bootloader
 PSEUDOMODULES += esp_gdbstub
 PSEUDOMODULES += esp_hw_counter
 PSEUDOMODULES += esp_i2c_hw
@@ -22,34 +25,94 @@ PSEUDOMODULES += esp_rtc_timer_32k
 PSEUDOMODULES += esp_spi_ram
 PSEUDOMODULES += esp_wifi_enterprise
 
-INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/
-INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/esp-idf/include
-INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/esp-idf/include/esp32
-INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/esp-idf/include/heap
-INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/esp-idf/include/spi_flash
-INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/esp-idf/include/tcpip_adapter
-INCLUDES += -I$(RIOTCPU)/$(CPU)
+INCLUDES += -I$(RIOTCPU)/$(CPU)/esp-idf/include
+INCLUDES += -I$(RIOTCPU)/$(CPU)/esp-idf/include/log
+
+INCLUDES += -I$(ESP32_SDK_DIR)/components/
+INCLUDES += -I$(ESP32_SDK_DIR)/components/driver/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_common/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_hw_support/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_hw_support/include/soc
+INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_rom/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_rom/include/$(CPU)
+INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_timer/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/hal/$(CPU)/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/hal/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/heap/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/log/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/newlib/platform_include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/soc/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/soc/$(CPU)/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/xtensa/include
+INCLUDES += -I$(ESP32_SDK_DIR)/components/xtensa/$(CPU)/include
+
+ifneq (,$(filter esp_spi_ram,$(USEMODULE)))
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_hw_support/include/soc/$(CPU)
+endif
+
+ifneq (,$(filter esp_idf_spi_flash,$(USEMODULE)))
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/bootloader_support/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/spi_flash/include
+endif
+
+ifneq (,$(filter esp_wifi_any,$(USEMODULE)))
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/bootloader_support/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_eth/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_event/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_netif/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_system/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_wifi/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/nvs_flash/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/spi_flash/include
+endif
+
+ifneq (,$(filter esp_wifi_enterprise,$(USEMODULE)))
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/wpa_supplicant/esp_supplicant/include
+endif
 
 ifneq (,$(filter esp_eth,$(USEMODULE)))
   INCLUDES += -I$(RIOTCPU)/$(CPU)/esp-eth
-  INCLUDES += -I$(RIOTCPU)/$(CPU)/vendor/esp-idf/include/ethernet
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_eth/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_event/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_netif/include
+  INCLUDES += -I$(ESP32_SDK_DIR)/components/esp_wifi/include
 endif
 
-CFLAGS += -DSDK_NOT_USED -DCONFIG_FREERTOS_UNICORE=1 -DESP_PLATFORM
+# we use ESP32 only in single core mode
+CFLAGS += -DCONFIG_ESP_SYSTEM_SINGLE_CORE_MODE
+CFLAGS += -DCONFIG_FREERTOS_UNICORE
+
+# other ESP-IDF configurations
+CFLAGS += -DCONFIG_IDF_TARGET_$(CPU_UC)
+CFLAGS += -DESP_PLATFORM
 CFLAGS += -DLOG_TAG_IN_BRACKETS
+
+# shortcuts used by ESP-IDF
+CFLAGS += -Dasm=__asm
+CFLAGS += -Dtypeof=__typeof__
 CFLAGS += -D_CONST=const
 
+LINKFLAGS += -L$(ESP32_SDK_DIR)/components/xtensa/$(CPU)
+ARCHIVES += -lxt_hal
+
 LINKFLAGS += -L$(RIOTCPU)/$(CPU)/ld/
-LINKFLAGS += -T$(RIOTCPU)/$(CPU)/ld/esp32.ld
-LINKFLAGS += -T$(RIOTCPU)/$(CPU)/ld/esp32.common.ld
-LINKFLAGS += -T$(RIOTCPU)/$(CPU)/ld/esp32.peripherals.ld
-LINKFLAGS += -T$(RIOTCPU)/$(CPU)/ld/esp32.rom.ld
-LINKFLAGS += -T$(RIOTCPU)/$(CPU)/ld/esp32.rom.nanofmt.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/soc/$(CPU)/ld/$(CPU).peripherals.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/esp_rom/$(CPU)/ld/$(CPU).rom.api.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/esp_rom/$(CPU)/ld/$(CPU).rom.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/esp_rom/$(CPU)/ld/$(CPU).rom.newlib-data.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/esp_rom/$(CPU)/ld/$(CPU).rom.newlib-funcs.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/esp_rom/$(CPU)/ld/$(CPU).rom.newlib-time.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/esp_rom/$(CPU)/ld/$(CPU).rom.spiflash.ld
+LINKFLAGS += -T$(ESP32_SDK_DIR)/components/esp_rom/$(CPU)/ld/$(CPU).rom.redefined.ld
+LINKFLAGS += -T$(RIOTCPU)/$(CPU)/ld/memory.ld
+LINKFLAGS += -T$(RIOTCPU)/$(CPU)/ld/sections.ld
 LINKFLAGS += -nostdlib -lgcc -Wl,-gc-sections
 
 # Libraries needed when using esp_wifi_any pseudomodule
 ifneq (,$(filter esp_wifi_any,$(USEMODULE)))
-  ARCHIVES += -lcore -lrtc -lnet80211 -lpp -lcoexist -lwps -lwpa -lwpa2
+  LINKFLAGS += -L$(ESP32_SDK_LIB_WIFI_DIR)/$(CPU)
+  LINKFLAGS += -L$(ESP32_SDK_LIB_PHY_DIR)/$(CPU)
+  ARCHIVES += -lcore -lrtc -lnet80211 -lpp -lcoexist
   ARCHIVES += -lphy -lstdc++
 endif
 
@@ -62,11 +125,16 @@ ifneq (,$(filter cpp,$(USEMODULE)))
   ARCHIVES += -lstdc++
 endif
 
+ifneq (,$(filter esp_bootloader,$(USEMODULE)))
+  # Bootloader file used by esptool.inc.mk
+  BOOTLOADER_BIN ?= $(BINDIR)/esp_bootloader/bootloader.bin
+endif
+
 ifneq (,$(filter esp_jtag,$(USEMODULE)))
   PROGRAMMERS_SUPPORTED += openocd
   PARTITION_POS = 0x8000
   OPENOCD_PRE_FLASH_CMDS = -c 'echo "Installing Bootloader at $(BOOTLOADER_POS)"' \
-    -c 'flash write_image erase "$(RIOTCPU)/$(CPU)/bin/bootloader.bin" $(BOOTLOADER_POS) bin' \
+    -c 'flash write_image erase "$(BOOTLOADER_BIN)" $(BOOTLOADER_POS) bin' \
     -c 'echo "Installing partition table at $(PARTITION_POS)"' \
     -c 'flash write_image erase "$(BINDIR)/partitions.bin" $(PARTITION_POS) bin'
   IMAGE_OFFSET = 0x10000
@@ -75,3 +143,5 @@ ifneq (,$(filter esp_jtag,$(USEMODULE)))
   # Without resets debug target fails with 'Target not examined yet'
   OPENOCD_DBG_EXTRA_CMD += -c 'reset halt'
 endif
+
+$(BOOTLOADER_BIN):
diff --git a/cpu/esp32/startup.c b/cpu/esp32/startup.c
index a0c216777b..f2425b354c 100644
--- a/cpu/esp32/startup.c
+++ b/cpu/esp32/startup.c
@@ -24,27 +24,31 @@
 #include <string.h>
 #include <sys/reent.h>
 
-#include "macros/units.h"
+/* RIOT headers have to be included before ESP-IDF headers! */
 #include "board.h"
-#include "esp_attr.h"
+#include "esp/common_macros.h"
 #include "exceptions.h"
 #include "irq_arch.h"
 #include "kernel_defines.h"
 #include "kernel_init.h"
 #include "log.h"
+#include "periph_cpu.h"
 #include "stdio_base.h"
 #include "syscalls.h"
 #include "thread_arch.h"
+#include "tools.h"
 
 #include "periph/cpuid.h"
 #include "periph/init.h"
 #include "periph/rtc.h"
 
+/* ESP-IDF headers */
 #include "driver/periph_ctrl.h"
-#include "esp/common_macros.h"
-#include "esp32/esp_sleep.h"
-#include "heap/esp_heap_caps_init.h"
-#include "log/esp_log.h"
+#include "esp_attr.h"
+#include "esp_heap_caps_init.h"
+#include "esp_log.h"
+#include "esp_sleep.h"
+#include "esp_timer.h"
 #include "rom/cache.h"
 #include "rom/ets_sys.h"
 #include "rom/rtc.h"
@@ -60,14 +64,15 @@
 #include "xtensa/core-macros.h"
 #include "xtensa/xtensa_api.h"
 
-#include "periph_cpu.h"
-#include "tools.h"
+#if IS_USED(MODULE_ESP_SPI_RAM)
+#include "spiram.h"
+#endif
 
-#ifdef MODULE_PUF_SRAM
+#if IS_USED(MODULE_PUF_SRAM)
 #include "puf_sram.h"
 #endif
 
-#ifdef MODULE_STDIO_UART
+#if IS_USED(MODULE_STDIO_UART)
 #include "stdio_uart.h"
 #endif
 
@@ -77,7 +82,7 @@
 #define STRINGIFY(s) STRINGIFY2(s)
 #define STRINGIFY2(s) #s
 
-#if MODULE_ESP_LOG_STARTUP
+#if IS_USED(MODULE_ESP_LOG_STARTUP)
 #define LOG_STARTUP(format, ...) LOG_TAG_EARLY(LOG_INFO, D, __func__, format, ##__VA_ARGS__)
 #else
 #define LOG_STARTUP(format, ...)
@@ -93,24 +98,35 @@ extern uint8_t _rtc_bss_start;
 extern uint8_t _rtc_bss_end;
 extern uint8_t _rtc_bss_rtc_start;
 extern uint8_t _rtc_bss_rtc_end;
-extern uint8_t _init_start;
+extern uint8_t _iram_start;
 
 /* external esp function declarations */
 extern void esp_clk_init(void);
 extern void esp_perip_clk_init(void);
 extern void esp_reent_init(struct _reent* r);
-extern void esp_panic_wdt_stop (void);
-extern void spi_ram_init(void);
-extern void spi_ram_heap_init(void);
 extern uint32_t hwrand (void);
 extern void bootloader_clock_configure(void);
 
+/* external RTC function declarations since they are not declared in headers */
+/* components/esp_hw_support/include/esp_private/esp_clk.h */
+extern int esp_clk_apb_freq(void);
+extern int esp_clk_cpu_freq(void);
+extern int esp_clk_xtal_freq(void);
+extern uint32_t esp_clk_slowclk_cal_get(void);
+/* components/esp_hw_support/include/soc/esp32/rtc.h */
+extern uint64_t esp_rtc_get_time_us(void);
+
+/* components/esp_system/port/include/esp_clk_internal.h */
+extern void IRAM_ATTR rtc_clk_select_rtc_slow_clk(rtc_slow_freq_t slow_clk);
+
 /* forward declarations */
 static void system_init(void);
 static void intr_matrix_clear(void);
 
 typedef int32_t esp_err_t;
 
+uint64_t g_startup_time = 0;
+
 /**
  * @brief   CPU startup function
  *
@@ -121,16 +137,16 @@ NORETURN void IRAM call_start_cpu0 (void)
 {
     register uint32_t *sp __asm__ ("a1"); (void)sp;
 
-    cpu_configure_region_protection();
+    esp_cpu_configure_region_protection();
 
     /* move exception vectors to IRAM */
-    asm volatile ("wsr %0, vecbase\n" ::"r"(&_init_start));
+    asm volatile ("wsr %0, vecbase\n" ::"r"(&_iram_start));
 
     RESET_REASON reset_reason = rtc_get_reset_reason(PRO_CPU_NUM);
 
     /* reset from panic handler by RWDT or TG0WDT */
     if (reset_reason == RTCWDT_SYS_RESET || reset_reason == TG0WDT_SYS_RESET) {
-        esp_panic_wdt_stop();
+        /* TODO esp_panic_wdt_stop was called here in former versions */
     }
 
 #ifdef MODULE_PUF_SRAM
@@ -157,7 +173,7 @@ NORETURN void IRAM call_start_cpu0 (void)
     uint8_t cpu_id[CPUID_LEN];
     cpuid_get ((void*)cpu_id);
 
-#ifdef MODULE_ESP_LOG_STARTUP
+#if IS_USED(MODULE_ESP_LOG_STARTUP)
     ets_printf("\n");
     LOG_STARTUP("Starting ESP32 with ID: ");
     for (unsigned i = 0; i < CPUID_LEN; i++) {
@@ -177,8 +193,8 @@ NORETURN void IRAM call_start_cpu0 (void)
     }
 
     LOG_STARTUP("Current clocks in Hz: CPU=%d APB=%d XTAL=%d SLOW=%d\n",
-                rtc_clk_cpu_freq_value(rtc_clk_cpu_freq_get()),
-                rtc_clk_apb_freq_get(), MHZ(rtc_clk_xtal_freq_get()),
+                esp_clk_cpu_freq(),
+                esp_clk_apb_freq(), esp_clk_xtal_freq(),
                 rtc_clk_slow_freq_get_hz());
 
     if (IS_ACTIVE(ENABLE_DEBUG)) {
@@ -207,9 +223,12 @@ NORETURN void IRAM call_start_cpu0 (void)
     }
 
     /* init SPI RAM if enabled */
-    #if CONFIG_SPIRAM_SUPPORT && CONFIG_SPIRAM_BOOT_INIT
-    spi_ram_init();
-    #endif
+#if CONFIG_SPIRAM_SUPPORT && CONFIG_SPIRAM_BOOT_INIT
+    if (esp_spiram_init() != ESP_OK) {
+        LOG_STARTUP("Failed to initialize SPI RAM\n");
+        exit(1);
+    }
+#endif
 
     LOG_STARTUP("PRO cpu starts user code\n");
     system_init();
@@ -217,12 +236,6 @@ NORETURN void IRAM call_start_cpu0 (void)
     UNREACHABLE();
 }
 
-#define RTC_FAST_FREQ_8M_MHZ    8000000
-#define rtc_select_slow_clk     select_rtc_slow_clk
-
-extern uint32_t esp_clk_slowclk_cal_get(void);
-extern void IRAM_ATTR rtc_select_slow_clk(rtc_slow_freq_t slow_clk);
-
 static void IRAM system_clk_init (void)
 {
     /* first initialize RTC with default configuration */
@@ -238,13 +251,13 @@ static void IRAM system_clk_init (void)
     /* set FAST_CLK to internal low power clock of 8 MHz */
     rtc_clk_fast_freq_set(RTC_FAST_FREQ_8M);
 
-#if MODULE_ESP_RTC_TIMER_32K
+#if IS_USED(MODULE_ESP_RTC_TIMER_32K)
     /* set SLOW_CLK to external 32.768 kHz crystal clock */
-    rtc_select_slow_clk(RTC_SLOW_FREQ_32K_XTAL);
+    rtc_clk_select_rtc_slow_clk(RTC_SLOW_FREQ_32K_XTAL);
 #else
     /* set SLOW_CLK to internal low power clock of 150 kHz */
     rtc_clk_32k_enable(false);
-    rtc_select_slow_clk(RTC_SLOW_FREQ_RTC);
+    rtc_clk_select_rtc_slow_clk(RTC_SLOW_FREQ_RTC);
 #endif
 
     LOG_STARTUP("Switching system clocks can lead to some unreadable characters\n");
@@ -267,11 +280,14 @@ static void IRAM system_clk_init (void)
                                                set to 2 MHz and handled later */
     }
 
-    uint32_t freq_before = rtc_clk_cpu_freq_value(rtc_clk_cpu_freq_get()) / MHZ(1);
+    uint32_t freq_before = esp_clk_cpu_freq() / MHZ;
 
     if (freq_before != CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ) {
+        rtc_cpu_freq_config_t clk_cfg;
+        rtc_clk_cpu_freq_to_config(freq, &clk_cfg);
+
         /* set configured CPU frequency */
-        rtc_clk_cpu_freq_set(freq);
+        rtc_clk_cpu_freq_set_config(&clk_cfg);
 
         /* Recalculate the ccount to make time calculation correct. */
         uint32_t freq_after = CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ;
@@ -294,6 +310,7 @@ static NORETURN void IRAM system_init (void)
 
     /* disable clocks of peripherals that are not needed at startup */
     esp_perip_clk_init();
+    g_startup_time = esp_rtc_get_time_us();
 
     /* set configured console UART baudrate */
     const int uart_clk_freq = rtc_clk_apb_freq_get();
@@ -328,15 +345,18 @@ static NORETURN void IRAM system_init (void)
     srand(hwrand());
 
     /* add SPI RAM to heap if enabled */
-    #if CONFIG_SPIRAM_SUPPORT && CONFIG_SPIRAM_BOOT_INIT
-    spi_ram_heap_init();
-    #endif
+#if CONFIG_SPIRAM_SUPPORT && CONFIG_SPIRAM_BOOT_INIT
+    esp_spiram_init_cache();
+    esp_spiram_add_to_heapalloc();
+#endif
 
     /* print some infos */
     LOG_STARTUP("Used clocks in Hz: CPU=%d APB=%d XTAL=%d FAST=%d SLOW=%d\n",
-                rtc_clk_cpu_freq_value(rtc_clk_cpu_freq_get()),
-                rtc_clk_apb_freq_get(), MHZ(rtc_clk_xtal_freq_get()),
-                RTC_FAST_FREQ_8M_MHZ, rtc_clk_slow_freq_get_hz());
+                esp_clk_cpu_freq(),
+                esp_clk_apb_freq(), esp_clk_xtal_freq(),
+                rtc_clk_fast_freq_get() == RTC_FAST_FREQ_8M ? 8 * MHZ
+                                                            : esp_clk_xtal_freq()/4,
+                rtc_clk_slow_freq_get_hz());
     LOG_STARTUP("XTAL calibration value: %d\n", esp_clk_slowclk_cal_get());
     LOG_STARTUP("Heap free: %u bytes\n", get_free_heap_size());
     uart_tx_wait_idle(CONFIG_CONSOLE_UART_NUM);
@@ -352,7 +372,7 @@ static NORETURN void IRAM system_init (void)
     periph_init();
 
     /* print system time */
-#ifdef MODULE_PERIPH_RTC
+#if IS_USED(MODULE_PERIPH_RTC)
     struct tm _sys_time;
     rtc_get_time(&_sys_time);
     LOG_STARTUP("System time: %04d-%02d-%02d %02d:%02d:%02d\n",
@@ -361,15 +381,15 @@ static NORETURN void IRAM system_init (void)
 #endif
 
     /* print the board config */
-#ifdef MODULE_ESP_LOG_STARTUP
+#if IS_USED(MODULE_ESP_LOG_STARTUP)
     print_board_config();
 #endif
 
-    #if MODULE_MTD
+#if IS_USED(MODULE_MTD)
     /* init flash drive */
     extern void spi_flash_drive_init (void);
     spi_flash_drive_init();
-    #endif
+#endif
 
     /* initialize the board */
     extern void board_init(void);
@@ -385,8 +405,11 @@ static NORETURN void IRAM system_init (void)
     extern void esp_event_handler_init(void);
     esp_event_handler_init();
 
+    /* initialize ESP-IDF timer task */
+    esp_timer_init();
+
     /* starting RIOT */
-#ifdef MODULE_ESP_LOG_STARTUP
+#if IS_USED(MODULE_ESP_LOG_STARTUP)
     LOG_STARTUP("Starting RIOT kernel on PRO cpu\n");
     uart_tx_wait_idle(CONFIG_CONSOLE_UART_NUM);
 #else