SAMA5: Enable the 32.768 crystal if SCHED_TICKLESS is selected

4 files changed, 19 insertions, 5 deletions

diff --git a/nuttx/configs/sama5d3x-ek/Kconfig b/nuttx/configs/sama5d3x-ek/Kconfig
index 8c7bcb84e..5444cd2d5 100644
--- a/nuttx/configs/sama5d3x-ek/Kconfig
+++ b/nuttx/configs/sama5d3x-ek/Kconfig
@@ -248,6 +248,11 @@ config SAMA5D3xEK_OV2640_DEMO
 
 endif # VIDEO_OV2640
 
+config SAMA5D3xEK_SLOWCLOCK
+	bool
+	default y if SCHED_TICKLESS
+	default n if !SCHED_TICKLESS
+
 if AUDIO_WM8904
 
 config SAMA5D3xEK_WM8904_I2CFREQUENCY
@@ -266,6 +271,7 @@ choice
 
 config SAMA5D3xEK_WM8904_SRCMAIN
 	bool "Main Clock (12MHz)"
+	select SAMA5D3xEK_SLOWCLOCK
 
 config SAMA5D3xEK_WM8904_SRCSCK
 	bool "Slow XTAL (32.768KHz)"
diff --git a/nuttx/configs/sama5d3x-ek/README.txt b/nuttx/configs/sama5d3x-ek/README.txt
index f3c6fa7d1..3b4de458f 100644
--- a/nuttx/configs/sama5d3x-ek/README.txt
+++ b/nuttx/configs/sama5d3x-ek/README.txt
@@ -2708,7 +2708,8 @@ Tickless OS
   NOTE: In most cases, the slow clock will be used as the timer/counter
   input.  You should enable the 32.768KHz crystal for the slow clock by
   calling sam_sckc_enable().  Otherwise, you will be doing all system
-  timing using the RC clock!
+  timing using the RC clock!  UPDATE: This will now be selected by default
+  when you configure for TICKLESS support.
 
   SAMA5 Timer Usage
   -----------------
diff --git a/nuttx/configs/sama5d3x-ek/src/sam_boot.c b/nuttx/configs/sama5d3x-ek/src/sam_boot.c
index fc28ecd53..42e2f9012 100644
--- a/nuttx/configs/sama5d3x-ek/src/sam_boot.c
+++ b/nuttx/configs/sama5d3x-ek/src/sam_boot.c
@@ -41,6 +41,7 @@
 
 #include <debug.h>
 
+#include "sam_sckc.h"
 #include "sama5d3x-ek.h"
 
 /************************************************************************************
@@ -60,13 +61,19 @@
  *
  * Description:
  *   All SAMA5 architectures must provide the following entry point.  This entry
- *   point is called early in the intitialization -- after all memory has been
+ *   point is called early in the initialization -- after all memory has been
  *   configured and mapped but before any devices have been initialized.
  *
  ************************************************************************************/
 
 void sam_boardinitialize(void)
 {
+#ifdef CONFIG_SAMA5D3xEK_SLOWCLOCK
+  /* Enable the external slow clock */
+
+  sam_sckc_enable(true);
+#endif
+
   /* Configure SPI chip selects if 1) SPI is enable, and 2) the weak function
    * sam_spiinitialize() has been brought into the link.
    */
diff --git a/nuttx/configs/sama5d3x-ek/src/sam_wm8904.c b/nuttx/configs/sama5d3x-ek/src/sam_wm8904.c
index 919e96089..d81e891fa 100644
--- a/nuttx/configs/sama5d3x-ek/src/sam_wm8904.c
+++ b/nuttx/configs/sama5d3x-ek/src/sam_wm8904.c
@@ -56,7 +56,6 @@
 #include "sam_pio.h"
 #include "sam_twi.h"
 #include "sam_ssc.h"
-#include "sam_sckc.h"
 #include "sam_pck.h"
 
 #include "sama5d3x-ek.h"
@@ -293,9 +292,10 @@ int sam_wm8904_initialize(int minor)
        */
 
 #ifdef CONFIG_SAMA5D3xEK_WM8904_SRCSCK
-      /* Drive the DAC with the slow clock (32.768 KHz) */
+      /* Drive the DAC with the slow clock (32.768 KHz).  The slow clock was
+       * enabled in sam_boot.c if needed.
+       */
 
-      sam_sckc_enable(true);
       (void)sam_pck_configure(PCK0, PCKSRC_SCK, BOARD_SLOWCLK_FREQUENCY);
 #else
       /* Drive the DAC with the main clock (12 MHz) */