arch/risc-v/espressif: Add DFS feature

Documentation/platforms/risc-v/esp32c3/boards/esp32c3-devkit/index.rst

@@ -447,6 +447,10 @@ Note: When normal mode COUNT is 0, it will switch to the next PM state where COU
 
 Note: During light sleep, overall current consumption of board should drop from 18mA (without any system load) to 1 mA on ESP32-C3 DevkitM-1.
 
+To save power without using sleep modes, lowering the clock speed is another approach. For dynamic frequency scaling
+``CONFIG_ESPRESSIF_DFS`` option needs to enabled and minimum CPU frequency needs to set under ``CONFIG_ESPRESSIF_MIN_CPU_FREQ`` option.
+With these options, the device scales the CPU clock according to workload.
+
 pwm
 ---
 

Documentation/platforms/risc-v/esp32c6/boards/esp32c6-devkitc/index.rst

@@ -464,6 +464,10 @@ Note: When normal mode COUNT is 0, it will switch to the next PM state where COU
 Note: During light sleep, overall current consumption of board should drop from 22mA (without any system load) to 1.3 mA on ESP32-C6 DevkitC-1.
 During deep sleep, current consumption of module (ESP32-C6-WROOM-1) should drop from 22mA (without any system load) to 48 μA.
 
+To save power without using sleep modes, lowering the clock speed is another approach. For dynamic frequency scaling
+``CONFIG_ESPRESSIF_DFS`` option needs to enabled and minimum CPU frequency needs to set under ``CONFIG_ESPRESSIF_MIN_CPU_FREQ`` option.
+With these options, the device scales the CPU clock according to workload.
+
 pwm
 ---
 

Documentation/platforms/risc-v/esp32h2/boards/esp32h2-devkit/index.rst

@@ -390,6 +390,10 @@ Note: When normal mode COUNT is 0, it will switch to the next PM state where COU
 Note: During light sleep, overall current consumption of board should drop from 14mA (without any system load) to 880 μA on ESP32-H2 DevkitM-1.
 During deep sleep, current consumption of module (ESP32-H2-MINI-1) should drop from 9mA (without any system load) to 8 μA.
 
+To save power without using sleep modes, lowering the clock speed is another approach. For dynamic frequency scaling
+``CONFIG_ESPRESSIF_DFS`` option needs to enabled and minimum CPU frequency needs to set under ``CONFIG_ESPRESSIF_MIN_CPU_FREQ`` option.
+With these options, the device scales the CPU clock according to workload.
+
 pwm
 ---
 

Documentation/platforms/risc-v/esp32p4/boards/esp32p4-function-ev-board/index.rst

@@ -291,6 +291,10 @@ System switch to the PM sleep mode, you need to enter::
     nsh> pmconfig relax normal
     nsh> pmconfig relax normal
 
+To save power without using sleep modes, lowering the clock speed is another approach. For dynamic frequency scaling
+``CONFIG_ESPRESSIF_DFS`` option needs to enabled and minimum CPU frequency needs to set under ``CONFIG_ESPRESSIF_MIN_CPU_FREQ`` option.
+With these options, the device scales the CPU clock according to workload.
+
 pwm
 ---
 

arch/risc-v/src/common/espressif/CMakeLists.txt

@@ -209,7 +209,7 @@ if(DEFINED ENV{ESP_HAL_3RDPARTY_VERSION})
       CACHE STRING "ESP HAL 3rdparty version")
 else()
   set(ESP_HAL_3RDPARTY_VERSION
-      b7e51db97a3f9dc82d3b3524d2bad298ba1e2647
+      2209449c9864c6d83a0ee2295f5b5299a2c6fb39
       CACHE STRING "ESP HAL 3rdparty version")
 endif()
 

arch/risc-v/src/common/espressif/Kconfig

@@ -126,6 +126,11 @@ config ESPRESSIF_CPU_FREQ_MHZ
 	default 360 if ESPRESSIF_CPU_FREQ_360
 	default 400 if ESPRESSIF_CPU_FREQ_400
 
+config ESPRESSIF_DFS
+	bool "Enable DFS (Dynamic Frequency Scaling)"
+	select PM
+	default n
+
 config ESPRESSIF_REGION_PROTECTION
 	bool "Enable region protection"
 	default y
@@ -162,6 +167,93 @@ config ESPRESSIF_SOC_RTC_MEM_SUPPORTED
 	bool
 	default n
 
+menu "Espressif DFS Options"
+	depends on ESPRESSIF_DFS
+
+choice ESPRESSIF_MIN_CPU_FREQ
+	prompt "Minimum CPU frequency"
+	default ESPRESSIF_MIN_CPU_FREQ_40 if ARCH_CHIP_ESP32P4 && ESPRESSIF_IDF_ENV_FPGA
+	default ESPRESSIF_MIN_CPU_FREQ_96 if ARCH_CHIP_ESP32H2
+	default ESPRESSIF_MIN_CPU_FREQ_160 if ARCH_CHIP_ESP32C3 || ARCH_CHIP_ESP32C6
+	default ESPRESSIF_MIN_CPU_FREQ_360 if ARCH_CHIP_ESP32P4 && ESP32P4_SELECTS_REV_LESS_V3
+	default ESPRESSIF_MIN_CPU_FREQ_400 if ARCH_CHIP_ESP32P4 && !ESP32P4_SELECTS_REV_LESS_V3
+	---help---
+		Minimum CPU frequency to be scale.
+
+config ESPRESSIF_MIN_CPU_FREQ_40
+	bool "40 MHz"
+	depends on ARCH_CHIP_ESP32C3 || ARCH_CHIP_ESP32C6 || ARCH_CHIP_ESP32P4
+	---help---
+		Set the minimum CPU frequency to 40 MHz.
+
+config ESPRESSIF_MIN_CPU_FREQ_48
+	bool "48 MHz"
+	depends on ARCH_CHIP_ESP32H2
+	---help---
+		Set the minimum CPU frequency to 48 MHz.
+
+config ESPRESSIF_MIN_CPU_FREQ_64
+	bool "64 MHz"
+	depends on ARCH_CHIP_ESP32H2
+	---help---
+		Set the minimum CPU frequency to 64 MHz.
+
+config ESPRESSIF_MIN_CPU_FREQ_80
+	bool "80 MHz"
+	depends on ARCH_CHIP_ESP32C3 || ARCH_CHIP_ESP32C6
+	---help---
+		Set the minimum CPU frequency to 80 MHz.
+
+config ESPRESSIF_MIN_CPU_FREQ_96
+	bool "96 MHz"
+	depends on ARCH_CHIP_ESP32H2
+	---help---
+		Set the minimum CPU frequency to 96 MHz.
+
+config ESPRESSIF_MIN_CPU_FREQ_160
+	bool "160 MHz"
+	depends on ARCH_CHIP_ESP32C3 || ARCH_CHIP_ESP32C6
+	---help---
+		Set the minimum CPU frequency to 160 MHz.
+
+config ESPRESSIF_MIN_CPU_FREQ_360
+	bool "360 MHz"
+	depends on ARCH_CHIP_ESP32P4 && ESP32P4_SELECTS_REV_LESS_V3
+	---help---
+		Set the minimum CPU frequency to 360 MHz.
+
+config ESPRESSIF_MIN_CPU_FREQ_400
+	bool "400 MHz"
+	depends on ARCH_CHIP_ESP32P4 && !ESP32P4_SELECTS_REV_LESS_V3
+	---help---
+		Set the minimum CPU frequency to 400 MHz.
+
+endchoice # ESPRESSIF_MIN_CPU_FREQ
+
+config ESPRESSIF_MAX_CPU_FREQ_MHZ
+	int
+	default 40 if ESPRESSIF_MAX_CPU_FREQ_40
+	default 48 if ESPRESSIF_MAX_CPU_FREQ_48
+	default 64 if ESPRESSIF_MAX_CPU_FREQ_64
+	default 80 if ESPRESSIF_MAX_CPU_FREQ_80
+	default 96 if ESPRESSIF_MAX_CPU_FREQ_96
+	default 160 if ESPRESSIF_MAX_CPU_FREQ_160
+	default 360 if ESPRESSIF_MAX_CPU_FREQ_360
+	default 400 if ESPRESSIF_MAX_CPU_FREQ_400
+
+config ESPRESSIF_MIN_CPU_FREQ_MHZ
+	int
+	default 40 if ESPRESSIF_MIN_CPU_FREQ_40
+	default 48 if ESPRESSIF_MIN_CPU_FREQ_48
+	default 64 if ESPRESSIF_MIN_CPU_FREQ_64
+	default 80 if ESPRESSIF_MIN_CPU_FREQ_80
+	default 96 if ESPRESSIF_MIN_CPU_FREQ_96
+	default 160 if ESPRESSIF_MIN_CPU_FREQ_160
+	default 360 if ESPRESSIF_MIN_CPU_FREQ_360
+	default 400 if ESPRESSIF_MIN_CPU_FREQ_400
+
+endmenu #
+
 menu "Espressif Log Level"
 	visible if DEBUG_FEATURES
 

arch/risc-v/src/common/espressif/Make.defs

@@ -217,7 +217,7 @@ endif
 
 ESP_HAL_3RDPARTY_REPO   = esp-hal-3rdparty
 ifndef ESP_HAL_3RDPARTY_VERSION
-	ESP_HAL_3RDPARTY_VERSION = b7e51db97a3f9dc82d3b3524d2bad298ba1e2647
+	ESP_HAL_3RDPARTY_VERSION = 2209449c9864c6d83a0ee2295f5b5299a2c6fb39
 endif
 
 ifndef ESP_HAL_3RDPARTY_URL

arch/risc-v/src/common/espressif/esp_gptimer.c

@@ -46,6 +46,9 @@
 #include "periph_ctrl.h"
 #include "soc/clk_tree_defs.h"
 #include "esp_private/esp_clk_tree_common.h"
+#ifdef CONFIG_PM
+#  include "include/esp_pm.h"
+#endif
 
 /****************************************************************************
  * Pre-processor Definitions
@@ -77,6 +80,9 @@ struct esp_timer_lowerhalf_s
   bool                      started;   /* True: Timer has been started */
   void                     *upper;     /* Pointer to timer_upperhalf_s */
   int                       group_id;  /* Timer group number */
+#ifdef CONFIG_PM
+  esp_pm_lock_handle_t      pm_lock;   /* Power management lock */
+#endif
 };
 
 /****************************************************************************
@@ -122,15 +128,21 @@ static const struct timer_ops_s g_timer_ops =
 static struct esp_timer_lowerhalf_s g_timer0_lowerhalf =
 {
   .ops = &g_timer_ops,
-  .group_id = 0
+  .group_id = 0,
+#ifdef CONFIG_PM
+  .pm_lock = NULL,
+#endif
 };
 
 /* TIMER1 lower-half */
 
 static struct esp_timer_lowerhalf_s g_timer1_lowerhalf =
 {
   .ops = &g_timer_ops,
-  .group_id = 1
+  .group_id = 1,
+#ifdef CONFIG_PM
+  .pm_lock = NULL,
+#endif
 };
 
 /****************************************************************************
@@ -171,6 +183,13 @@ static int esp_timer_start(struct timer_lowerhalf_s *lower)
 
   timer_hal_context_t *hal = &(priv->hal);
 
+#ifdef CONFIG_PM
+  if (priv->pm_lock != NULL)
+    {
+      esp_pm_lock_acquire(priv->pm_lock);
+    }
+#endif
+
   /* Make sure the timer is stopped to avoid unpredictable behavior */
 
   timer_ll_enable_intr(hal->dev, TIMER_LL_EVENT_ALARM(hal->timer_id),
@@ -282,6 +301,13 @@ static int esp_timer_stop(struct timer_lowerhalf_s *lower)
                        false);
   timer_ll_enable_counter(hal->dev, hal->timer_id, false);
 
+#ifdef CONFIG_PM
+  if (priv->pm_lock != NULL)
+    {
+      esp_pm_lock_release(priv->pm_lock);
+    }
+#endif
+
   priv->started = false;
   priv->callback = NULL;
 
@@ -542,6 +568,11 @@ int esp_timer_initialize(int group_id)
   char *devpath;
   shared_periph_module_t periph;
   int irq;
+#ifdef CONFIG_PM
+  int ret;
+  bool need_pm_lock = true;
+  esp_pm_lock_type_t pm_lock_type = ESP_PM_NO_LIGHT_SLEEP;
+#endif
 
   switch (group_id)
     {
@@ -590,6 +621,34 @@ int esp_timer_initialize(int group_id)
 
   timer_hal_init(&lower->hal, lower->group_id, lower->hal.timer_id);
 
+#ifdef CONFIG_PM
+#  if TIMER_LL_FUNC_CLOCK_SUPPORT_RC_FAST
+  if (GPTIMER_CLK_SRC_DEFAULT == GPTIMER_CLK_SRC_RC_FAST)
+    {
+      need_pm_lock = false;
+    }
+#  endif
+
+#  if TIMER_LL_FUNC_CLOCK_SUPPORT_APB
+  if (GPTIMER_CLK_SRC_DEFAULT == GPTIMER_CLK_SRC_APB)
+    {
+      pm_lock_type = ESP_PM_APB_FREQ_MAX;
+    }
+#  endif
+
+  if (need_pm_lock && lower->pm_lock == NULL)
+    {
+      ret = esp_pm_lock_create(pm_lock_type, 0,
+                               "TIMER",
+                               &lower->pm_lock);
+      if (ret != OK)
+        {
+          tmrerr("Failed to create GPTIMER PM lock\n");
+          return -ENOMEM;
+        }
+    }
+#endif
+
   /* Register the timer driver as /dev/timerX. If the registration goes
    * right the returned value from timer_register is a pointer to
    * timer_upperhalf_s that can be either used with timer_unregister()