xtensa/esp32: Changes in rtc driver to support rtc wdt driver

arch/xtensa/src/esp32/esp32_rtc.c

@@ -30,6 +30,7 @@
 #include "hardware/esp32_rtccntl.h"
 #include "hardware/esp32_dport.h"
 #include "hardware/esp32_i2s.h"
+#include "esp32_rtc.h"
 #include "xtensa.h"
 #include "xtensa_attr.h"
 
@@ -79,18 +80,9 @@
 
 #define RTC_FAST_CLK_FREQ_APPROX    8500000
 
-/* 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 detection
- * (i.e. oscillator runs for a few cycles and then stops).
- */
-
-#define SLOW_CLK_CAL_CYCLES         1024
-
 /* Disable logging from the ROM code. */
 
 #define RTC_DISABLE_ROM_LOG ((1 << 0) | (1 << 16))
-#define EXT_OSC_FLAG    BIT(3)
 
 /* Default initializer for esp32_rtc_sleep_config_t
  * This initializer sets all fields to "reasonable" values
@@ -136,56 +128,6 @@
  * Private Types
  ****************************************************************************/
 
-/* RTC SLOW_CLK frequency values */
-
-enum esp32_rtc_slow_freq_e
-{
-  RTC_SLOW_FREQ_RTC = 0,      /* Internal 150 kHz RC oscillator */
-  RTC_SLOW_FREQ_32K_XTAL = 1, /* External 32 kHz XTAL */
-  RTC_SLOW_FREQ_8MD256 = 2,   /* Internal 8 MHz RC oscillator, divided by 256 */
-};
-
-/* RTC FAST_CLK frequency values */
-
-enum esp32_rtc_fast_freq_e
-{
-  RTC_FAST_FREQ_XTALD4 = 0,   /* Main XTAL, divided by 4 */
-  RTC_FAST_FREQ_8M = 1,       /* Internal 8 MHz RC oscillator */
-};
-
-/* This is almost the same as esp32_rtc_slow_freq_e, except that we define
- * an extra enum member for the external 32k oscillator.For convenience,
- * lower 2 bits should correspond to esp32_rtc_slow_freq_e values.
- */
-
-enum esp32_slow_clk_sel_e
-{
-  /* Internal 150 kHz RC oscillator */
-
-  SLOW_CLK_150K = RTC_SLOW_FREQ_RTC,
-
-  /* External 32 kHz XTAL */
-
-  SLOW_CLK_32K_XTAL = RTC_SLOW_FREQ_32K_XTAL,
-
-  /* Internal 8 MHz RC oscillator, divided by 256 */
-
-  SLOW_CLK_8MD256 = RTC_SLOW_FREQ_8MD256,
-
-  /* External 32k oscillator connected to 32K_XP pin */
-
-  SLOW_CLK_32K_EXT_OSC = RTC_SLOW_FREQ_32K_XTAL | EXT_OSC_FLAG
-};
-
-/* Clock source to be calibrated using rtc_clk_cal function */
-
-enum esp32_rtc_cal_sel_e
-{
-  RTC_CAL_RTC_MUX = 0,       /* Currently selected RTC SLOW_CLK */
-  RTC_CAL_8MD256 = 1,        /* Internal 8 MHz RC oscillator, divided by 256 */
-  RTC_CAL_32K_XTAL = 2       /* External 32 kHz XTAL */
-};
-
 /* RTC power and clock control initialization settings */
 
 struct esp32_rtc_priv_s
@@ -245,8 +187,6 @@ static void IRAM_ATTR esp32_rtc_clk_fast_freq_set(
                       enum esp32_rtc_fast_freq_e fast_freq);
 static uint32_t IRAM_ATTR esp32_rtc_clk_cal_internal(
                 enum esp32_rtc_cal_sel_e cal_clk, uint32_t slowclk_cycles);
-static uint32_t IRAM_ATTR esp32_rtc_clk_cal(enum esp32_rtc_cal_sel_e cal_clk,
-                                                    uint32_t slowclk_cycles);
 static void IRAM_ATTR esp32_rtc_clk_slow_freq_set(
                       enum esp32_rtc_slow_freq_e slow_freq);
 static void esp32_select_rtc_slow_clk(enum esp32_slow_clk_sel_e slow_clk);
@@ -475,41 +415,6 @@ static uint32_t IRAM_ATTR esp32_rtc_clk_cal_internal(
   return REG_GET_FIELD(TIMG_RTCCALICFG1_REG(0), TIMG_RTC_CALI_VALUE);
 }
 
-/****************************************************************************
- * Name: esp32_rtc_clk_cal
- *
- * Description:
- *   Measure RTC slow clock's period, based on main XTAL frequency
- *
- * Input Parameters:
- *   cal_clk        - clock to be measured
- *   slowclk_cycles - number of slow clock cycles to average
- *
- * Returned Value:
- *   Average slow clock period in microseconds, Q13.19 fixed point format
- *   or 0 if calibration has timed out
- *
- ****************************************************************************/
-
-static uint32_t IRAM_ATTR esp32_rtc_clk_cal(enum esp32_rtc_cal_sel_e cal_clk,
-                                                     uint32_t slowclk_cycles)
-{
-  enum esp32_rtc_xtal_freq_e xtal_freq;
-  uint64_t xtal_cycles;
-  uint64_t divider;
-  uint64_t period_64;
-  uint32_t period;
-
-  xtal_freq = esp32_rtc_clk_xtal_freq_get();
-  xtal_cycles = esp32_rtc_clk_cal_internal(cal_clk, slowclk_cycles);
-  divider = ((uint64_t)xtal_freq) * slowclk_cycles;
-  period_64 = ((xtal_cycles << RTC_CLK_CAL_FRACT) + divider / 2 - 1)
-                                                          / divider;
-  period = (uint32_t)(period_64 & UINT32_MAX);
-
-  return period;
-}
-
 /****************************************************************************
  * Name: esp32_rtc_clk_slow_freq_set
  *
@@ -574,6 +479,69 @@ static void esp32_select_rtc_slow_clk(enum esp32_slow_clk_sel_e slow_clk)
  * Public Functions
  ****************************************************************************/
 
+/****************************************************************************
+ * Name: esp32_rtc_get_slow_clk_rtc
+ *
+ * Description:
+ *   Get slow_clk_rtc source.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   The clock source:
+ *   -  SLOW_CK
+ *   -  CK_XTAL_32K
+ *   -  CK8M_D256_OUT
+ *
+ ****************************************************************************/
+
+enum esp32_rtc_slow_freq_e IRAM_ATTR esp32_rtc_get_slow_clk(void)
+{
+  enum esp32_rtc_slow_freq_e slow_freq;
+
+  /* Get the clock source for slow_clk_rtc */
+
+  slow_freq = REG_GET_FIELD(RTC_CNTL_CLK_CONF_REG, RTC_CNTL_ANA_CLK_RTC_SEL);
+
+  return slow_freq;
+}
+
+/****************************************************************************
+ * Name: esp32_rtc_clk_cal
+ *
+ * Description:
+ *   Measure RTC slow clock's period, based on main XTAL frequency
+ *
+ * Input Parameters:
+ *   cal_clk        - clock to be measured
+ *   slowclk_cycles - number of slow clock cycles to average
+ *
+ * Returned Value:
+ *   Average slow clock period in microseconds, Q13.19 fixed point format
+ *   or 0 if calibration has timed out
+ *
+ ****************************************************************************/
+
+uint32_t IRAM_ATTR esp32_rtc_clk_cal(enum esp32_rtc_cal_sel_e cal_clk,
+                                                     uint32_t slowclk_cycles)
+{
+  enum esp32_rtc_xtal_freq_e xtal_freq;
+  uint64_t xtal_cycles;
+  uint64_t divider;
+  uint64_t period_64;
+  uint32_t period;
+
+  xtal_freq = esp32_rtc_clk_xtal_freq_get();
+  xtal_cycles = esp32_rtc_clk_cal_internal(cal_clk, slowclk_cycles);
+  divider = ((uint64_t)xtal_freq) * slowclk_cycles;
+  period_64 = ((xtal_cycles << RTC_CLK_CAL_FRACT) + divider / 2 - 1)
+                                                          / divider;
+  period = (uint32_t)(period_64 & UINT32_MAX);
+
+  return period;
+}
+
 enum esp32_rtc_xtal_freq_e rtc_get_xtal(void)
                 __attribute__((alias("esp32_rtc_clk_xtal_freq_get")));
 

arch/xtensa/src/esp32/esp32_rtc.h

@@ -30,6 +30,7 @@
  ****************************************************************************/
 
 #include <nuttx/config.h>
+#include "hardware/esp32_soc.h"
 
 #ifndef __ASSEMBLY__
 
@@ -42,6 +43,24 @@ extern "C"
 #define EXTERN extern
 #endif
 
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* 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 detection
+ * (i.e. oscillator runs for a few cycles and then stops).
+ */
+
+#define SLOW_CLK_CAL_CYCLES         1024
+
+/* Indicates that 32k oscillator gets input from external oscillator
+ * instead of a crystal.
+ */
+
+#define EXT_OSC_FLAG    BIT(3)
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/
@@ -58,10 +77,98 @@ enum esp32_rtc_xtal_freq_e
   RTC_XTAL_FREQ_24M = 24,     /* 24 MHz XTAL */
 };
 
+/* RTC SLOW_CLK frequency values */
+
+enum esp32_rtc_slow_freq_e
+{
+  RTC_SLOW_FREQ_RTC = 0,      /* Internal 150 kHz RC oscillator */
+  RTC_SLOW_FREQ_32K_XTAL = 1, /* External 32 kHz XTAL */
+  RTC_SLOW_FREQ_8MD256 = 2,   /* Internal 8 MHz RC oscillator, divided by 256 */
+};
+
+/* RTC FAST_CLK frequency values */
+
+enum esp32_rtc_fast_freq_e
+{
+  RTC_FAST_FREQ_XTALD4 = 0,   /* Main XTAL, divided by 4 */
+  RTC_FAST_FREQ_8M = 1,       /* Internal 8 MHz RC oscillator */
+};
+
+/* This is almost the same as esp32_rtc_slow_freq_e, except that we define
+ * an extra enum member for the external 32k oscillator. For convenience,
+ * lower 2 bits should correspond to esp32_rtc_slow_freq_e values.
+ */
+
+enum esp32_slow_clk_sel_e
+{
+  /* Internal 150 kHz RC oscillator */
+
+  SLOW_CLK_150K = RTC_SLOW_FREQ_RTC,
+
+  /* External 32 kHz XTAL */
+
+  SLOW_CLK_32K_XTAL = RTC_SLOW_FREQ_32K_XTAL,
+
+  /* Internal 8 MHz RC oscillator, divided by 256 */
+
+  SLOW_CLK_8MD256 = RTC_SLOW_FREQ_8MD256,
+
+  /* External 32k oscillator connected to 32K_XP pin */
+
+  SLOW_CLK_32K_EXT_OSC = RTC_SLOW_FREQ_32K_XTAL | EXT_OSC_FLAG
+};
+
+/* Clock source to be calibrated using rtc_clk_cal function */
+
+enum esp32_rtc_cal_sel_e
+{
+  RTC_CAL_RTC_MUX = 0,       /* Currently selected RTC SLOW_CLK */
+  RTC_CAL_8MD256 = 1,        /* Internal 8 MHz RC oscillator, divided by 256 */
+  RTC_CAL_32K_XTAL = 2       /* External 32 kHz XTAL */
+};
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
 
+/****************************************************************************
+ * Name: esp32_rtc_get_slow_clk_rtc
+ *
+ * Description:
+ *   Get slow_clk_rtc source.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   The clock source:
+ *   -  SLOW_CK
+ *   -  CK_XTAL_32K
+ *   -  CK8M_D256_OUT
+ *
+ ****************************************************************************/
+
+enum esp32_rtc_slow_freq_e esp32_rtc_get_slow_clk(void);
+
+/****************************************************************************
+ * Name: esp32_rtc_clk_cal
+ *
+ * Description:
+ *   Measure RTC slow clock's period, based on main XTAL frequency
+ *
+ * Input Parameters:
+ *   cal_clk        - clock to be measured
+ *   slowclk_cycles - number of slow clock cycles to average
+ *
+ * Returned Value:
+ *   Average slow clock period in microseconds, Q13.19 fixed point format
+ *   or 0 if calibration has timed out
+ *
+ ****************************************************************************/
+
+uint32_t esp32_rtc_clk_cal(enum esp32_rtc_cal_sel_e cal_clk,
+                                                    uint32_t slowclk_cycles);
+
 /****************************************************************************
  * Name: esp32_rtc_clk_xtal_freq_get
  *