SAMA5: Add register level debug option for SPI

3 files changed, 113 insertions, 6 deletions

diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index 8a8713623..1769f774b 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -5280,8 +5280,8 @@
 	  SAMA5 DMAC controllers.  Initial check-in is untested and is a
 	  straight leverage from the SAM3/4 (2013-8-4).
 	* arch/arm/src/sama5/sam_spi.c, sam_spi.h, and chip/sam_spi.h:
-	  Leverage SPI support from SAM/3/4.  Initial check-inis untested
+	  Leverage SPI support from SAM/3/4.  Initial check-in is untested
 	  and have several limitations:  No DMA, no SPI1 support (2013-8-4).
 	* arch/arm/src/sama5/sam_spi.c and sam_spi.h:  Now supports SPI1
-	  (2013-8-4).
+	  and a register access debug option (2013-8-4).
 
diff --git a/nuttx/arch/arm/src/sama5/Kconfig b/nuttx/arch/arm/src/sama5/Kconfig
index d74cb7c93..798572356 100644
--- a/nuttx/arch/arm/src/sama5/Kconfig
+++ b/nuttx/arch/arm/src/sama5/Kconfig
@@ -238,6 +238,17 @@ config PIOE_IRQ
 
 endif # PIO_IRQ
 
+menu "SPI device driver options"
+
+config SAMA5_SPI_REGDEBUG
+	bool "SPI Register level debug"
+	depends on (SAMA5_SPI0 || SAMA5_SPI1) && DEBUG
+	default n
+	---help---
+		Output detailed register-level SPI device debug information.  Requires also DEBUG.
+
+endmenu # SPI device driver options
+
 menu "External Memory Configuration"
 
 config SAMA5_DDRCS
diff --git a/nuttx/arch/arm/src/sama5/sam_spi.c b/nuttx/arch/arm/src/sama5/sam_spi.c
index ab196fa6e..e9d68ebd6 100644
--- a/nuttx/arch/arm/src/sama5/sam_spi.c
+++ b/nuttx/arch/arm/src/sama5/sam_spi.c
@@ -88,6 +88,7 @@
 #ifndef CONFIG_DEBUG
 #  undef CONFIG_DEBUG_VERBOSE
 #  undef CONFIG_DEBUG_SPI
+#  undef CONFIG_SAMA5_SPI_REGDEBUG
 #endif
 
 #ifdef CONFIG_DEBUG_SPI
@@ -136,6 +137,15 @@ struct sam_spidev_s
   bool initialized;            /* TRUE: Controller has been initialized */
   const uint32_t *csraddr;     /* Addresses of CSR register */
   select_t select;             /* SPI select callout */
+
+  /* Debug stuff */
+
+#ifdef CONFIG_SAMA5_SPI_REGDEBUG
+   bool     wrlast;            /* Last was a write */
+   uint32_t addresslast;       /* Last address */
+   uint32_t valuelast;         /* Last value */
+   int      ntimes;            /* Number of times */
+#endif
 };
 
 /****************************************************************************
@@ -144,10 +154,23 @@ struct sam_spidev_s
 
 /* Helpers */
 
+#ifdef CONFIG_SAMA5_SPI_REGDEBUG
+static bool     spi_checkreg(struct sam_spidev_s *spi, bool wr,
+                  uint32_t value, uint32_t address);
+#else
+# define        spi_checkreg(spi,wr,value,address) (false)
+#endif
+
+static inline uint32_t spi_getreg(struct sam_spidev_s *spi,
+                  unsigned int offset);
+static inline void spi_putreg(struct sam_spidev_s *spi, uint32_t value,
+                  unsigned int offset);
+static inline struct sam_spidev_s *spi_device(struct sam_spics_s *spics);
+
 #if defined(CONFIG_DEBUG_SPI) && defined(CONFIG_DEBUG_VERBOSE)
-static void spi_dumpregs(struct sam_spidev_s *spi, const char *msg);
+static void     spi_dumpregs(struct sam_spidev_s *spi, const char *msg);
 #else
-# define spi_dumpregs(spi,msg)
+# define        spi_dumpregs(spi,msg)
 #endif
 
 static inline void spi_flush(struct sam_spidev_s *spi);
@@ -272,6 +295,60 @@ static struct sam_spidev_s g_spi1dev =
  ****************************************************************************/
 
 /****************************************************************************
+ * Name: spi_checkreg
+ *
+ * Description:
+ *   Check if the current register access is a duplicate of the preceding.
+ *
+ * Input Parameters:
+ *   value   - The value to be written
+ *   address - The address of the register to write to
+ *
+ * Returned Value:
+ *   true:  This is the first register access of this type.
+ *   flase: This is the same as the preceding register access.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SAMA5_SPI_REGDEBUG
+static bool spi_checkreg(struct sam_spidev_s *spi, bool wr, uint32_t value,
+                         uint32_t address)
+{
+  if (wr      == spi->wrlast &&     /* Same kind of access? */
+      value   == spi->valuelast &&  /* Same value? */
+      address == spi->addresslast)  /* Same address? */
+    {
+      /* Yes, then just keep a count of the number of times we did this. */
+
+      spi->ntimes++;
+      return false;
+    }
+  else
+    {
+      /* Did we do the previous operation more than once? */
+
+      if (spi->ntimes > 0)
+        {
+          /* Yes... show how many times we did it */
+
+          lldbg("...[Repeats %d times]...\n", spi->ntimes);
+        }
+
+      /* Save information about the new access */
+
+      spi->wrlast      = wr;
+      spi->valuelast   = value;
+      spi->addresslast = address;
+      spi->ntimes      = 0;
+    }
+
+  /* Return true if this is the first time that we have done this operation */
+
+  return true;
+}
+#endif
+
+/****************************************************************************
  * Name: spi_getreg
  *
  * Description:
@@ -282,7 +359,17 @@ static struct sam_spidev_s g_spi1dev =
 static inline uint32_t spi_getreg(struct sam_spidev_s *spi,
                                   unsigned int offset)
 {
-  return getreg32(spi->base + offset);
+  uint32_t address = spi->base + offset;
+  uint32_t value = getreg32(address);
+
+#ifdef CONFIG_SAMA5_SPI_REGDEBUG
+  if (spi_checkreg(spi, false, value, address))
+    {
+      lldbg("%08x->%08x\n", address, value);
+    }
+#endif
+
+  return value;
 }
 
 /****************************************************************************
@@ -296,7 +383,16 @@ static inline uint32_t spi_getreg(struct sam_spidev_s *spi,
 static inline void spi_putreg(struct sam_spidev_s *spi, uint32_t value,
                               unsigned int offset)
 {
-  spi_putreg(spi, value, spi->base + offset);
+  uint32_t address = spi->base + offset;
+
+#ifdef CONFIG_SAMA5_SPI_REGDEBUG
+  if (spi_checkreg(spi, true, value, address))
+    {
+      lldbg("%08x<-%08x\n", address, value);
+    }
+#endif
+
+  spi_putreg(spi, value, address);
 }
 
 /****************************************************************************