Add logic to support the FSMC SRAM in the NuttX heap

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4433 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 181 insertions, 31 deletions

diff --git a/nuttx/arch/arm/src/stm32/stm32_allocateheap.c b/nuttx/arch/arm/src/stm32/stm32_allocateheap.c
index b097a9644..be7862e11 100644
--- a/nuttx/arch/arm/src/stm32/stm32_allocateheap.c
+++ b/nuttx/arch/arm/src/stm32/stm32_allocateheap.c
@@ -54,35 +54,208 @@
 /****************************************************************************
  * Private Definitions
  ****************************************************************************/
+/* Internal SRAM is available in all members of the STM32 family. The
+ * following definitions must be provided to specify the size and
+ * location of internal(system) SRAM:
+ *
+ * CONFIG_DRAM_END            : End address (+1) of SRAM (F1 family only, the
+ *                            : F4 family uses the a priori end of SRAM)
+ *
+ * The F4 family also contains internal TCM SRAM.  This SRAM is different
+ * because it cannot be used for DMA.  So if DMA needed, then the following
+ * should be defined to exclude TCM SRAM from the heap:
+ *
+ * CONFIG_STM32_TCMEXCLUDE    : Exclude TCM SRAM from the HEAP
+ *
+ * In addition to internal SRAM, SRAM may also be available through the FSMC.
+ * In order to use FSMC SRAM, the following additional things need to be
+ * present in the NuttX configuration file:
+ *
+ * CONFIG_STM32_FSMC=y        : Enables the FSMC
+ * CONFIG_STM32_FSMC_SRAM=y   : Indicates that SRAM is available via the
+ *   FSMC (as opposed to an LCD or FLASH).
+ * CONFIG_HEAP2_BASE          : The base address of the SRAM in the FSMC
+ *   address space
+ * CONFIG_HEAP2_END           : The end (+1) of the SRAM in the FSMC
+ *   address space
+ * CONFIG_MM_REGIONS          : Must be set to a large enough value to
+ *   include the FSMC SRAM (as determined by the rules provided below)
+ */
+
+#ifndef CONFIG_STM32_FSMC
+#  undef CONFIG_STM32_FSMC_SRAM
+#endif
 
-/* For the STM312F10xxx family, all SRAM is in a contiguous block starting
- * at g_heapbase and extending through CONFIG_DRAM_END (my apologies for
- * the bad naming).
+/* For the STM312F10xxx family, all internal SRAM is in one contiguous block
+ * starting at g_heapbase and extending through CONFIG_DRAM_END (my apologies for
+ * the bad naming).  In addition, external FSMC SRAM may be available.
  */
 
 #if defined(CONFIG_STM32_STM32F10XX)
+   /* Set the end of system SRAM */
+
 #  define SRAM1_END CONFIG_DRAM_END
 
+   /* Check if external FSMC SRAM is provided */
+
+#  if CONFIG_STM32_FSMC_SRAM
+#    if CONFIG_MM_REGIONS < 2
+#      warning "FSMC SRAM not included in the heap"
+#      undef CONFIG_STM32_FSMC_SRAM
+#    elif CONFIG_MM_REGIONS > 2
+#      error "CONFIG_MM_REGIONS > 2 but I don't know what any of the region(s) are"
+#      undef CONFIG_MM_REGIONS
+#      define CONFIG_MM_REGIONS 2
+#    endif
+#  elif CONFIG_MM_REGIONS > 1
+#    error "CONFIG_MM_REGIONS > 1 but I don't know what any of the region(s) are"
+#  endif
+
+   /* The STM32 F1 has not TCM SRAM */
+
+#  undef CONFIG_STM32_TCMEXCLUDE
+#  define CONFIG_STM32_TCMEXCLUDE 1
+
 /* All members of the STM32F40xxx family have 192Kb in three banks:
  *
- * 1) 112Kb of SRAM beginning at address 0x2000:0000
- * 2)  16Kb of SRAM beginning at address 0x2001:c000
+ * 1) 112Kb of System SRAM beginning at address 0x2000:0000
+ * 2)  16Kb of System SRAM beginning at address 0x2001:c000
  * 3)  64Kb of TCM SRAM beginning at address 0x1000:0000
  *
  * As determined by ld.script, g_heapbase lies in the 112Kb memory
  * region and that extends to 0x2001:0000.  But the  first and second memory
  * regions are contiguous and treated as one in this logic that extends to
  * 0x2002:0000.
+ *
+ * As a complication, it appears that TCM SRAM cannot be used for DMA.  So, if
+ * STM32 DMA is enabled, TCM SRAM should probably be excluded from the heap.
+ *
+ * In addition, external FSMC SRAM may be available.
  */
 
 #elif defined(CONFIG_STM32_STM32F40XX)
+   /* Set the end of system SRAM */
+
 #  define SRAM1_END   0x20020000
+
+   /* Set the range of TCM SRAM as well (although we may not use it) */
+
 #  define SRAM2_START 0x10000000
 #  define SRAM2_END   0x10010000
+
+   /* There are 4 possible SRAM configurations:
+    *
+    * Configuration 1. System SRAM (only)
+    *                  CONFIG_MM_REGIONS == 1
+    *                  CONFIG_STM32_FSMC_SRAM NOT defined
+    *                  CONFIG_STM32_TCMEXCLUDE defined
+    * Configuration 2. System SRAM and TCM SRAM
+    *                  CONFIG_MM_REGIONS == 2
+    *                  CONFIG_STM32_FSMC_SRAM NOT defined
+    *                  CONFIG_STM32_TCMEXCLUDE NOT defined
+    * Configuration 3. System SRAM and FSMC SRAM
+    *                  CONFIG_MM_REGIONS == 2
+    *                  CONFIG_STM32_FSMC_SRAM defined
+    *                  CONFIG_STM32_TCMEXCLUDE defined
+    * Configuration 4. System SRAM, TCM SRAM, and FSMC SRAM
+    *                  CONFIG_MM_REGIONS == 3
+    *                  CONFIG_STM32_FSMC_SRAM defined
+    *                  CONFIG_STM32_TCMEXCLUDE NOT defined
+    *
+    * Let's make sure that all definitions are consitent before doing
+    * anything else
+    */
+
+#  if defined(CONFIG_STM32_FSMC_SRAM)
+
+   /* Configuration 3 or 4. External SRAM is available.  CONFIG_MM_REGIONS
+    * should be at least 2.
+    */
+
+#    if CONFIG_MM_REGIONS < 2
+       /* Only one memory region.  Force Configuration 1 */
+
+#      warning "FSMC SRAM (and TCM SRAM) excluded from the heap"
+#      undef CONFIG_STM32_FSMC_SRAM
+#      undef CONFIG_STM32_TCMEXCLUDE
+#      define CONFIG_STM32_TCMEXCLUDE 1
+
+   /* CONFIG_MM_REGIONS may be 3 if TCM SRAM is included in the head */
+
+#    elif CONFIG_MM_REGIONS > 2
+
+       /* More than two memory regions.  This is okay if TCM SRAM is not
+        * disabled.
+        */
+
+#      if defined(CONFIG_STM32_TCMEXCLUDE)
+
+         /* Configuration 3: CONFIG_MM_REGIONS should have been 2 */
+
+#        error "CONFIG_MM_REGIONS > 2 but I don't know what any of the region(s) are"
+#        undef CONFIG_MM_REGIONS
+#        define CONFIG_MM_REGIONS 2
+#      else
+
+         /* Configuration 4: DMA should be disabled and CONFIG_MM_REGIONS
+          * should be 3.
+          */
+
+#        ifdef (CONFIG_STM32_DMA)
+#          warning "TCM SRAM is included in the heap AND DMA is enabled"
+#        endif
+#        if CONFIG_MM_REGIONS != 3
+#          error "CONFIG_MM_REGIONS > 3 but I don't know what any of the region(s) are"
+#          undef CONFIG_MM_REGIONS
+#          define CONFIG_MM_REGIONS 3
+#        endif
+#      endif
+
+   /* CONFIG_MM_REGIONS is exactly 2.  We cannot support both TCM SRAM and
+    * FSMC SRAM.
+    */
+
+#    elif !defined(CONFIG_STM32_TCMEXCLUDE)
+#      error "CONFIG_MM_REGIONS == 2, cannot support both TCM SRAM and FSMC SRAM"
+#      undef CONFIG_STM32_TCMEXCLUDE
+#      define CONFIG_STM32_TCMEXCLUDE 1
+#    endif
+   
+#  elif !defined(CONFIG_STM32_TCMEXCLUDE)
+
+   /* Configuration 2: FSMC SRAM is not used, but TCM SRAM is requested.  DMA
+    * should be disabled and CONFIG_MM_REGIONS should be 2.
+    */
+
+#    ifdef (CONFIG_STM32_DMA)
+#      warning "TCM SRAM is included in the heap AND DMA is enabled"
+#    endif
+#    if CONFIG_MM_REGIONS < 2
+#      error "TCM SRAM excluded from the heap because CONFIG_MM_REGIONS < 2"
+#      undef CONFIG_STM32_TCMEXCLUDE
+#      define CONFIG_STM32_TCMEXCLUDE 1
+#    elif CONFIG_MM_REGIONS > 2
+#      error "CONFIG_MM_REGIONS > 2 but I don't know what any of the region(s) are"
+#      undef CONFIG_MM_REGIONS
+#      define CONFIG_MM_REGIONS 2
+#    endif
+#  endif
 #else
 #  error "Unsupported STM32 chip"
 #endif
 
+/* If FSMC SRAM is going to be used as heap, then verify that the starting
+ * address and size of the external SRAM region has been provided in the
+ * configuration.
+ */
+
+#ifdef CONFIG_STM32_FSMC_SRAM
+#  if !defined(CONFIG_HEAP2_BASE) || !defined(CONFIG_HEAP2_END)
+#    error "CONFIG_HEAP2_BASE and CONFIG_HEAP2_END must be provided"
+#    undef CONFIG_STM32_FSMC_SRAM
+#  endif
+#endif
+
 /****************************************************************************
  * Private Data
  ****************************************************************************/
@@ -123,41 +296,18 @@ void up_allocate_heap(FAR void **heap_start, size_t *heap_size)
  ****************************************************************************/
 
 #if CONFIG_MM_REGIONS > 1
-#  if defined(CONFIG_STM32_STM32F40XX)
-#    if defined(CONFIG_HEAP2_BASE) && defined(CONFIG_HEAP2_END)
-#      if CONFIG_MM_REGIONS > 3
-#        error "CONFIG_MM_REGIONS > 3 but I don't know what all of the regions are"
-#      endif
-#    elif CONFIG_MM_REGIONS > 2
-#      error "CONFIG_MM_REGIONS > 2 but I don't know what all of the regions are"
-#    endif
-
 void up_addregion(void)
 {
   /* Add the STM32F40xxx TCM SRAM heap region. */
 
+#ifndef CONFIG_STM32_TCMEXCLUDE
    mm_addregion((FAR void*)SRAM2_START, SRAM2_END-SRAM2_START);
+#endif
 
    /* Add the user specified heap region. */
 
-#  if CONFIG_MM_REGIONS > 2 && defined(CONFIG_HEAP2_BASE) && defined(CONFIG_HEAP2_END)
+#ifdef CONFIG_STM32_FSMC_SRAM
    mm_addregion((FAR void*)CONFIG_HEAP2_BASE, CONFIG_HEAP2_END - CONFIG_HEAP2_BASE);
 #  endif
 }
-
-#  elif defined(CONFIG_HEAP2_BASE) && defined(CONFIG_HEAP2_END)
-#    if CONFIG_MM_REGIONS > 2
-#      error "CONFIG_MM_REGIONS > 2 but I don't know what all of the regions are"
-#    endif
-
-void up_addregion(void)
-{
-  /* Add the user specified heap region. */
-
-  mm_addregion((FAR void*)CONFIG_HEAP2_BASE, CONFIG_HEAP2_END - CONFIG_HEAP2_BASE);
-}
-
-#  else
-#    error "CONFIG_MM_REGIONS > 1 but I don't know what any of the region(s) are"
-#  endif
 #endif