Merge branch 'feature/disable_some_perip_clk_when_cpu_start' into 'master'

Disable some peripheral clocks when cpu starts

See merge request !1089

components/esp32/clk.c

@@ -25,6 +25,8 @@
 #include "soc/soc.h"
 #include "soc/rtc.h"
 #include "soc/rtc_cntl_reg.h"
+#include "soc/dport_reg.h"
+#include "soc/i2s_reg.h"
 
 /* Number of cycles to wait from the 32k XTAL oscillator to consider it running.
  * Larger values increase startup delay. Smaller values may cause false positive
@@ -125,3 +127,89 @@ static void select_rtc_slow_clk(rtc_slow_freq_t slow_clk)
     ESP_EARLY_LOGD(TAG, "RTC_SLOW_CLK calibration value: %d", cal_val);
     esp_clk_slowclk_cal_set(cal_val);
 }
+
+/* This function is not exposed as an API at this point.
+ * All peripheral clocks are default enabled after chip is powered on.
+ * This function disables some peripheral clocks when cpu starts.
+ * These peripheral clocks are enabled when the peripherals are initialized
+ * and disabled when they are de-initialized.
+ */
+void esp_perip_clk_init(void)
+{
+    uint32_t common_perip_clk, hwcrypto_perip_clk, wifi_bt_sdio_clk = 0;
+
+#if CONFIG_FREERTOS_UNICORE
+    RESET_REASON rst_reas[1];
+#else
+    RESET_REASON rst_reas[2];
+#endif
+
+    rst_reas[0] = rtc_get_reset_reason(0);
+
+#if !CONFIG_FREERTOS_UNICORE
+    rst_reas[1] = rtc_get_reset_reason(1);
+#endif
+
+    /* For reason that only reset CPU, do not disable the clocks
+     * that have been enabled before reset.
+     */
+    if ((rst_reas[0] >= TGWDT_CPU_RESET && rst_reas[0] <= RTCWDT_CPU_RESET)
+#if !CONFIG_FREERTOS_UNICORE
+        || (rst_reas[1] >= TGWDT_CPU_RESET && rst_reas[1] <= RTCWDT_CPU_RESET)
+#endif
+    ) {
+        common_perip_clk = ~DPORT_READ_PERI_REG(DPORT_PERIP_CLK_EN_REG);
+        hwcrypto_perip_clk = ~DPORT_READ_PERI_REG(DPORT_PERI_CLK_EN_REG);
+        wifi_bt_sdio_clk = ~DPORT_READ_PERI_REG(DPORT_WIFI_CLK_EN_REG);
+    }
+    else {
+        common_perip_clk = DPORT_WDG_CLK_EN |
+                              DPORT_I2S0_CLK_EN |
+                              DPORT_UART1_CLK_EN |
+                              DPORT_SPI_CLK_EN |
+                              DPORT_I2C_EXT0_CLK_EN |
+                              DPORT_UHCI0_CLK_EN |
+                              DPORT_RMT_CLK_EN |
+                              DPORT_PCNT_CLK_EN |
+                              DPORT_LEDC_CLK_EN |
+                              DPORT_UHCI1_CLK_EN |
+                              DPORT_TIMERGROUP1_CLK_EN |
+                              DPORT_SPI_CLK_EN_2 |
+                              DPORT_PWM0_CLK_EN |
+                              DPORT_I2C_EXT1_CLK_EN |
+                              DPORT_CAN_CLK_EN |
+                              DPORT_PWM1_CLK_EN |
+                              DPORT_I2S1_CLK_EN |
+                              DPORT_SPI_DMA_CLK_EN |
+                              DPORT_UART2_CLK_EN |
+                              DPORT_PWM2_CLK_EN |
+                              DPORT_PWM3_CLK_EN;
+        hwcrypto_perip_clk = DPORT_PERI_EN_AES |
+                                DPORT_PERI_EN_SHA |
+                                DPORT_PERI_EN_RSA |
+                                DPORT_PERI_EN_SECUREBOOT;
+        wifi_bt_sdio_clk = DPORT_WIFI_CLK_WIFI_EN |
+                              DPORT_WIFI_CLK_BT_EN_M |
+                              DPORT_WIFI_CLK_UNUSED_BIT5 |
+                              DPORT_WIFI_CLK_UNUSED_BIT12 |
+                              DPORT_WIFI_CLK_SDIOSLAVE_EN |
+                              DPORT_WIFI_CLK_SDIO_HOST_EN |
+                              DPORT_WIFI_CLK_EMAC_EN;
+    }
+    /* Change I2S clock to audio PLL first. Because if I2S uses 160MHz clock,
+     * the current is not reduced when disable I2S clock.
+     */
+    DPORT_SET_PERI_REG_MASK(I2S_CLKM_CONF_REG(0), I2S_CLKA_ENA);
+    DPORT_SET_PERI_REG_MASK(I2S_CLKM_CONF_REG(1), I2S_CLKA_ENA);
+
+    /* Disable some peripheral clocks. */
+    DPORT_CLEAR_PERI_REG_MASK(DPORT_PERIP_CLK_EN_REG, common_perip_clk);
+    DPORT_SET_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, common_perip_clk);
+
+    /* Disable hardware crypto clocks. */
+    DPORT_CLEAR_PERI_REG_MASK(DPORT_PERI_CLK_EN_REG, hwcrypto_perip_clk);
+    DPORT_SET_PERI_REG_MASK(DPORT_PERI_RST_EN_REG, hwcrypto_perip_clk);
+
+    /* Disable WiFi/BT/SDIO clocks. */
+    DPORT_CLEAR_PERI_REG_MASK(DPORT_WIFI_CLK_EN_REG, wifi_bt_sdio_clk);
+}

components/esp32/cpu_start.c

@@ -239,6 +239,7 @@ void start_cpu0_default(void)
     trax_start_trace(TRAX_DOWNCOUNT_WORDS);
 #endif
     esp_clk_init();
+    esp_perip_clk_init();
     intr_matrix_clear();
 #ifndef CONFIG_CONSOLE_UART_NONE
     uart_div_modify(CONFIG_CONSOLE_UART_NUM, (rtc_clk_apb_freq_get() << 4) / CONFIG_CONSOLE_UART_BAUDRATE);

components/esp32/include/esp_clk.h

@@ -54,3 +54,11 @@ uint32_t esp_clk_slowclk_cal_get();
  */
 void esp_clk_slowclk_cal_set(uint32_t value);
 
+/**
+ * @brief Disables clock of some peripherals
+ *
+ * Called from cpu_start.c, not intended to be called from other places.
+ * This function disables clock of useless peripherals when cpu starts.
+ */
+void esp_perip_clk_init(void);
+

components/soc/esp32/include/soc/dport_reg.h

@@ -1055,6 +1055,8 @@
 #define DPORT_WIFI_CLK_BT_EN_S  11
 /* Remaining single bit clock masks */
 #define DPORT_WIFI_CLK_SDIOSLAVE_EN  BIT(4)
+#define DPORT_WIFI_CLK_UNUSED_BIT5  BIT(5)
+#define DPORT_WIFI_CLK_UNUSED_BIT12  BIT(12)
 #define DPORT_WIFI_CLK_SDIO_HOST_EN  BIT(13)
 #define DPORT_WIFI_CLK_EMAC_EN  BIT(14)
 #define DPORT_WIFI_CLK_RNG_EN  BIT(15)