Fix some errors in stm32_allocateheap.c for STM32 F1 and F3 that crept in recently

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5776 42af7a65-404d-4744-a932-0658087f49c3

2 files changed, 65 insertions, 8 deletions

diff --git a/nuttx/configs/sam3u-ek/README.txt b/nuttx/configs/sam3u-ek/README.txt
index e94a9a319..2e0c50f9d 100644
--- a/nuttx/configs/sam3u-ek/README.txt
+++ b/nuttx/configs/sam3u-ek/README.txt
@@ -419,8 +419,52 @@ must be is one of the following:
          nuttx.hex         - The pass2 Intel HEX file (selected in defconfig)
          System.map        - Symbols in the kernel-space ELF file
 
-    The J-Link programmer will except files in .hex, .mot, .srec, and .bin
-    formats.
+       The J-Link programmer will except files in .hex, .mot, .srec, and .bin
+       formats.
+
+    4. Combining .hex files.  If you plan to use the .hex files with your
+       debugger or FLASH utility, then you may need to combine the two hex
+       files into a single .hex file.  Here is how you can do that.
+
+       a. The 'tail' of the nuttx.hex file should look something like this
+          (with my comments added):
+
+            $ tail nuttx.hex
+            # 00, data records
+            ...
+            :10 9DC0 00 01000000000800006400020100001F0004
+            :10 9DD0 00 3B005A0078009700B500D400F300110151
+            :08 9DE0 00 30014E016D0100008D
+            # 05, Start Linear Address Record
+            :04 0000 05 0800 0419 D2
+            # 01, End Of File record
+            :00 0000 01 FF
+
+          Use an editor such as vi to remove the 05 and 01 records.
+
+       b. The 'head' of the nuttx_user.hex file should look something like
+          this (again with my comments added):
+
+            $ head nuttx_user.hex
+            # 04, Extended Linear Address Record
+            :02 0000 04 0801 F1
+            # 00, data records
+            :10 8000 00 BD89 01084C800108C8110208D01102087E
+            :10 8010 00 0010 00201C1000201C1000203C16002026
+            :10 8020 00 4D80 01085D80010869800108ED83010829
+            ...
+
+          Nothing needs to be done here.  The nuttx_user.hex file should
+          be fine.
+
+       c. Combine the edited nuttx.hex and un-edited nuttx_user.hex
+          file to produce a single combined hex file:
+
+          $ cat nuttx.hex nuttx_user.hex >combined.hex
+
+       Then use the combined.hex file with the to write the FLASH image.
+       If you do this a lot, you will probably want to invest a little time
+       to develop a tool to automate these steps.
 
   nsh:
     Configures the NuttShell (nsh) located at examples/nsh.  The
diff --git a/nuttx/configs/sam3u-ek/scripts/memory.ld b/nuttx/configs/sam3u-ek/scripts/memory.ld
index f88c4c80b..13405f408 100644
--- a/nuttx/configs/sam3u-ek/scripts/memory.ld
+++ b/nuttx/configs/sam3u-ek/scripts/memory.ld
@@ -33,17 +33,30 @@
  *
  ****************************************************************************/
 
-/* The AT91SAM3U-4 has 256Kb of FLASH beginning at address 0x0008:0000,
- * 32Kb of SRAM beginning at address 0x2000:0000, and 16Kb of SRAM beginning
+/* The AT91SAM3U-4 has 256KB of FLASH beginning at address 0x0008:0000,
+ * 32KB of SRAM beginning at address 0x2000:0000, and 16Kb of SRAM beginning
  * at address 0x2008:000 (used only for heap).  When booting from FLASH,
  * FLASH memory is aliased to address 0x0000:0000 where the code expects to
  * begin execution by jumping to the entry point in the 0x0800:0000 address
  * range.
  *
- * For MPU support, the kernel-mode NuttX section is assumed to be 64Kb of
- * FLASH and 4Kb of SRAM.  That, of course, can be optimized as needed (See
- * also configs/open1788/scripts/kernel-space.ld).  A detailed memory map
- * for the CPU SRAM region is as follows:
+ * For MPU support, the kernel-mode NuttX section is assumed to be 64KB of
+ * FLASH and 4KB of SRAM.  That, of course, can be optimized as needed (See
+ * also configs/open1788/scripts/kernel-space.ld).
+ *
+ * Alignment of the user space FLASH partition is a critical factor: The
+ * user space FLASH partition will be spanned with a single region of size
+ * 2**n bytes.  The alignment of the user-space region must be the same.  As
+ * a consequence, as the user-space increases in size, the alignmment
+ * requirement also increases.
+ *
+ * This alignment requirement means that the largest user space FLASH region
+ * you can have will be 2128KB at it would have to be positioned at
+ * 0x000a0000.  If you change this address, don't forget to chagne the
+ * CONFIG_NUTTX_USERSPACE configuration setting to match and to modify
+ * the check in kernel/userspace.c.
+ *
+ * A detailed memory map for the 16Kb SRAM region is as follows:
  *
  *   0x20000 0000:  Kernel .data region.  Typical size: 0.1KB
  *   ------- ----   Kernel .bss  region.  Typical size: 1.8KB