SAMA5D23 boards: When running out of SDRAM, need to query the PMC to determine operating frequency

arch/arm/src/sama5/sam_clockconfig.c

@@ -56,6 +56,11 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
+#undef NEED_PLLSETUP
+#if defined(CONFIG_SAMA5_BOOT_ISRAM) || defined(CONFIG_SAMA5_BOOT_CS0FLASH)
+#  define NEED_PLLSETUP 1
+#endif
+
 /****************************************************************************
  * Private Types
  ****************************************************************************/
@@ -80,6 +85,7 @@
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static void sam_pmcwait(uint32_t bit)
 {
   /* There is no timeout on this wait.  Why not?  Because the symptoms there
@@ -90,15 +96,17 @@ static void sam_pmcwait(uint32_t bit)
 
   while ((getreg32(SAM_PMC_SR) & bit) == 0);
 }
+#endif
 
 /****************************************************************************
  * Name: sam_enablemosc
  *
  * Description:
- *   Enable the main osciallator
+ *   Enable the main oscillator
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static inline void sam_enablemosc(void)
 {
   uint32_t regval;
@@ -141,6 +149,7 @@ static inline void sam_enablemosc(void)
       sam_pmcwait(PMC_INT_MCKRDY);
     }
 }
+#endif
 
 /****************************************************************************
  * Name: sam_selectmosc
@@ -152,6 +161,7 @@ static inline void sam_enablemosc(void)
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static inline void sam_selectmosc(void)
 {
   uint32_t regval;
@@ -167,6 +177,7 @@ static inline void sam_selectmosc(void)
 
   sam_pmcwait(PMC_INT_MCKRDY);
 }
+#endif
 
 /****************************************************************************
  * Name: sam_pllasetup
@@ -178,6 +189,7 @@ static inline void sam_selectmosc(void)
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static inline void sam_pllasetup(void)
 {
   uint32_t regval;
@@ -197,6 +209,7 @@ static inline void sam_pllasetup(void)
 
   sam_pmcwait(PMC_INT_LOCKA);
 }
+#endif
 
 /****************************************************************************
  * Name: sam_plladivider
@@ -206,6 +219,7 @@ static inline void sam_pllasetup(void)
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static inline void sam_plladivider(void)
 {
   uint32_t regval;
@@ -246,6 +260,7 @@ static inline void sam_plladivider(void)
 
   sam_pmcwait(PMC_INT_MCKRDY);
 }
+#endif
 
 /****************************************************************************
  * Name: sam_mckprescaler
@@ -255,6 +270,7 @@ static inline void sam_plladivider(void)
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static inline void sam_mckprescaler(void)
 {
   uint32_t regval;
@@ -270,6 +286,7 @@ static inline void sam_mckprescaler(void)
 
   sam_pmcwait(PMC_INT_MCKRDY);
 }
+#endif
 
 /****************************************************************************
  * Name: sam_mckdivider
@@ -280,6 +297,7 @@ static inline void sam_mckprescaler(void)
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static inline void sam_mckdivider(void)
 {
   uint32_t regval;
@@ -295,6 +313,7 @@ static inline void sam_mckdivider(void)
 
   sam_pmcwait(PMC_INT_MCKRDY);
 }
+#endif
 
 /****************************************************************************
  * Name: sam_selectplla
@@ -304,6 +323,7 @@ static inline void sam_mckdivider(void)
  *
  ****************************************************************************/
 
+#if defined(NEED_PLLSETUP)
 static inline void sam_selectplla(void)
 {
   uint32_t regval;
@@ -319,6 +339,7 @@ static inline void sam_selectplla(void)
 
   sam_pmcwait(PMC_INT_MCKRDY);
 }
+#endif
 
 /****************************************************************************
  * Name: sam_usbclockconfig
@@ -569,8 +590,8 @@ void sam_clockconfig(void)
 #ifdef CONFIG_SAMA5_BOOT_CS0FLASH
   if (config)
 #endif /* CONFIG_SAMA5_BOOT_CS0FLASH */
-#if defined(CONFIG_SAMA5_BOOT_ISRAM) || defined(CONFIG_SAMA5_BOOT_CS0FLASH)
     {
+#if defined(NEED_PLLSETUP)
       /* Enable main oscillator (if it has not already been selected) */
 
       sam_enablemosc();
@@ -601,10 +622,10 @@ void sam_clockconfig(void)
       /* Finally, elect the PLLA output as the input clock for PCK and MCK. */
 
       sam_selectplla();
+#endif /* NEED_PLLSETUP */
 
       /* Setup USB clocking */
 
       sam_usbclockconfig();
     }
-#endif /* CONFIG_SAMA5_BOOT_ISRAM || CONFIG_SAMA5_BOOT_CS0FLASH */
 }

arch/arm/src/sama5/sam_pmc.h

@@ -65,7 +65,7 @@ extern "C"
  * Name: sam_pllack_frequency
  *
  * Description:
- *   Given the Main Clock frequency that provides the input to PLLA, return 
+ *   Given the Main Clock frequency that provides the input to PLLA, return
  *   the frequency of the PPA output clock, PLLACK
  *
  * Assumptions:
@@ -76,11 +76,26 @@ extern "C"
 
 uint32_t sam_pllack_frequency(uint32_t mainclk);
 
+/****************************************************************************
+ * Name: sam_plladiv2_frequency
+ *
+ * Description:
+ *   The PLLACK input to most clocking may or may not be divided by two.
+ *   This function will return the possibly divided PLLACK clock input
+ *   frequency.
+ *
+ * Assumptions:
+ *   See sam_pllack_frequency.
+ *
+ ****************************************************************************/
+
+uint32_t sam_plladiv2_frequency(uint32_t mainclk);
+
 /****************************************************************************
  * Name: sam_pck_frequency
  *
  * Description:
- *   Given the Main Clock frequency that provides the input to PLLA, return 
+ *   Given the Main Clock frequency that provides the input to PLLA, return
  *   the frequency of the processor clock (PCK).
  *
  * Assumptions:
@@ -95,7 +110,7 @@ uint32_t sam_pck_frequency(uint32_t mainclk);
  * Name: sam_mck_frequency
  *
  * Description:
- *   Given the Main Clock frequency that provides the input to PLLA, return 
+ *   Given the Main Clock frequency that provides the input to PLLA, return
  *   the frequency of the PPA output clock, PLLACK
  *
  * Assumptions:
@@ -106,6 +121,30 @@ uint32_t sam_pck_frequency(uint32_t mainclk);
 
 uint32_t sam_mck_frequency(uint32_t mainclk);
 
+/************************************************************************************
+ * Name: sam_hsmci_clkdiv
+ *
+ * Description:
+ *   Multimedia Card Interface clock (MCCK or MCI_CK) is Master Clock (MCK)
+ *   divided by (2*(CLKDIV) + CLOCKODD + 2).
+ *
+ *     CLKFULLDIV = 2*CLKDIV + CLOCKODD;
+ *     MCI_SPEED  = MCK / (CLKFULLDIV + 2)
+ *     CLKFULLDIV = MCK / MCI_SPEED - 2
+ *
+ *     CLKDIV     = CLKFULLDIV >> 1
+ *     CLOCKODD   = CLKFULLDIV & 1
+ *
+ *   Where CLKDIV has a range of 0-255.
+ *
+ * TODO: This belongs elsewhere
+ *
+ ************************************************************************************/
+
+#ifdef CONFIG_ARCH_HAVE_SDIO
+uint32_t sam_hsmci_clkdiv(uint32_t target);
+#endif
+
 #undef EXTERN
 #if defined(__cplusplus)
 }

arch/arm/src/sama5/sam_timerisr.c

@@ -70,14 +70,6 @@
 
 #define PIT_PIV ((PIT_CLOCK + (CLK_TCK >> 1)) / CLK_TCK)
 
-/* The size of the reload field is 20 bits.  Verify that the reload value
- * will fit in the reload register.
- */
-
-#if PIT_PIV > PIT_MR_PIV_MASK
-#  error PIT_PIV exceeds the maximum value
-#endif
-
 /****************************************************************************
  * Private Types
  ****************************************************************************/
@@ -149,7 +141,10 @@ void up_timerinit(void)
    * interrupts from the PIT.
    */
 
-  regval = PIT_PIV | PIT_MR_PITEN | PIT_MR_PITIEN;
+  regval  = PIT_PIV;
+  DEBUGASSERT(regval <= PIT_MR_PIV_MASK);
+
+  regval |= (PIT_MR_PITEN | PIT_MR_PITIEN);
   putreg32(regval, SAM_PIT_MR);
 
   /* And enable the timer interrupt */