Add pcDuino patch needed for booting. Update README to explain why

configs/pcduino-a10/README.txt

@@ -103,6 +103,7 @@ Contents
   - Buttons
   - JTAG
   - Booting NuttX from an SD card
+  - Configurations
 
 pcDuino v1 Connectors
 =====================
@@ -316,3 +317,95 @@ Booting NuttX from an SD card
        microSD slot.  Reset the pcDuino and NuttX should be running.
 
   Reference: https://www.olimex.com/wiki/Bare_Metal_programming_A13#Stand_alone_program_running_with_uboot
+
+Configurations
+==============
+
+  Information Common to All Configurations
+  ----------------------------------------
+  Each pcDuino configuration is maintained in a sub-directory and
+  can be selected as follow:
+
+    cd tools
+    ./configure.sh pcduino-a10/<subdir>
+    cd -
+    . ./setenv.sh
+
+  Before sourcing the setenv.sh file above, you should examine it and perform
+  edits as necessary so that TOOLCHAIN_BIN is the correct path to the directory
+  than holds your toolchain binaries.
+
+  And then build NuttX by simply typing the following.  At the conclusion of
+  the make, the nuttx binary will reside in an ELF file called, simply, nuttx.
+
+    make
+
+  The <subdir> that is provided above as an argument to the tools/configure.sh
+  must be is one of the following.
+
+  NOTES:
+
+  1. These configurations use the mconf-based configuration tool.  To
+    change any of these configurations using that tool, you should:
+
+    a. Build and install the kconfig-mconf tool.  See nuttx/README.txt
+       and misc/tools/
+
+    b. Execute 'make menuconfig' in nuttx/ in order to start the
+       reconfiguration process.
+
+  2. Unless stated otherwise, all configurations generate console
+     output on UART0.
+
+  3. All of these configurations use the Code Sourcery for Windows toolchain
+     (unless stated otherwise in the description of the configuration).  That
+     toolchain selection can easily be reconfigured using 'make menuconfig'.
+     Here are the relevant current settings:
+
+     Build Setup:
+       CONFIG_HOST_WINDOS=y                    : Microsoft Windows
+       CONFIG_WINDOWS_CYGWIN=y                 : Using Cygwin or other POSIX environment
+
+     System Type -> Toolchain:
+       CONFIG_ARMV7A_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery for Windows
+
+     The setenv.sh file is available for you to use to set the PATH
+     variable.  The path in the that file may not, however, be correct
+     for your installation.  Try 'which arm-none-eabi-gcc' to make sure that
+     you are selecting the right tool.
+
+  Configuration Sub-directories
+  -----------------------------
+
+  nsh:
+
+    This configuration directory provide the NuttShell (NSH).  There are
+
+    STATUS:
+      This configuration builds and runs, but only if the patch at
+      nuttx/configs/pcduino-a10/nsh/pcduino-140107.patch is applied.  This patchfile
+      contains some fixes that are as-of-yet not well understood and so cannot be checked
+      in.  Below is a summary of the kludges currently in this patch file:
+
+      a) nuttx/arch/arm/src/armv7-a/arm_head.S: Initializes the MMU so that A10
+         peripherals can be accessed very early.  This is not normally necessary, but
+         is required because of certain debug statements that seem to be necessary
+         in a1x_boot.c (see the next item).
+
+      b) nuttx/arch/arm/src/a1x/a1x_boot.c:  This file contains several arbitrary
+         statements that just output debug information.  Some of these can be removed,
+         but if you remove all of the debug output, the pcDuino will not boot.  No
+         idea yet why.
+
+      c) nuttx/arch/arm/src/armv7-a/arm_mmu.c:  After setting a page table entry
+         for the MMU, the MMU's TLBs are flushed for that memory region.  That
+         flushing must currently be commented out.  Why?  I am not sure, but I
+         think that this is because TLBs are being flushed why they are in use.  For
+         the pcDuino, we are executing out of SDRAM so when the TLBs for the SDRAM
+         region are invalidated that cause a crash.  That has not been proven,
+         however.
+
+      d) nuttx/arch/arm/src/common/up_internal.h:  One of the values need for UART
+         baud calculation is missing (the frequency of SCLK, the UART input clock).
+         As a result, UART configuration is currently suppressed by a setting in
+         this file.

configs/pcduino-a10/nsh/pcduino-140107.patch

@@ -0,0 +1,106 @@
+diff --git a/nuttx/arch/arm/src/a1x/a1x_boot.c b/nuttx/arch/arm/src/a1x/a1x_boot.c
+index 3cc6323..ad42790 100644
+--- a/nuttx/arch/arm/src/a1x/a1x_boot.c
++++ b/nuttx/arch/arm/src/a1x/a1x_boot.c
+@@ -312,12 +312,14 @@ void up_boot(void)
+    * for all IO regions (Including the vector region).
+    */
+ 
++lowsyslog("Calling a1x_setupmappings\n"); // REMOVE ME
+   a1x_setupmappings();
+ 
+   /* Provide a special mapping for the IRAM interrupt vector positioned in
+    * high memory.
+    */
+ 
++lowsyslog("Calling a1x_vectormapping\n"); // REMOVE ME
+   a1x_vectormapping();
+ 
+ #endif /* CONFIG_ARCH_ROMPGTABLE */
+@@ -326,16 +328,19 @@ void up_boot(void)
+    * arm_vector.S
+    */
+ 
++lowsyslog("Calling a1x_copyvectorblock\n"); // REMOVE ME
+   a1x_copyvectorblock();
+ 
+   /* Initialize the FPU */
+ 
+ #ifdef CONFIG_ARCH_FPU
++lowsyslog("Calling arm_fpuconfig\n"); // REMOVE ME
+   arm_fpuconfig();
+ #endif
+ 
+   /* Perform common, low-level chip initialization (might do nothing) */
+ 
++lowsyslog("Calling a1x_lowsetup\n"); // REMOVE ME
+   a1x_lowsetup();
+ 
+   /* Perform early serial initialization if we are going to use the serial
+@@ -343,6 +348,7 @@ void up_boot(void)
+    */
+ 
+ #ifdef USE_EARLYSERIALINIT
++lowsyslog("Calling up_earlyserialinit\n"); // REMOVE ME
+   up_earlyserialinit();
+ #endif
+ 
+@@ -353,6 +359,7 @@ void up_boot(void)
+    */
+ 
+ #ifdef CONFIG_NUTTX_KERNEL
++lowsyslog("Calling a1x_userspace\n"); // REMOVE ME
+   a1x_userspace();
+ #endif
+ 
+@@ -362,5 +369,7 @@ void up_boot(void)
+    * - Configuration of board specific resources (PIOs, LEDs, etc).
+    */
+ 
++lowsyslog("Calling a1x_boardinitialize\n"); // REMOVE ME
+   a1x_boardinitialize();
++lowsyslog("Returning\n"); // REMOVE ME
+ }
+diff --git a/nuttx/arch/arm/src/armv7-a/arm_head.S b/nuttx/arch/arm/src/armv7-a/arm_head.S
+index bce82d5..924bd24 100644
+--- a/nuttx/arch/arm/src/armv7-a/arm_head.S
++++ b/nuttx/arch/arm/src/armv7-a/arm_head.S
+@@ -220,6 +220,12 @@ __start:
+ 	teq		r0, r2
+ 	bne		.Lpgtableclear
+ 
++	movw	r1, #0x0416 // REMOVE ME
++	movt	r1, #0x01c0
++	movw	r2, #0x4070
++	movt	r2, #0x0000
++	str		r1, [r2]
++
+ #ifdef ARMV7A_PGTABLE_MAPPING
+ 	/* If the page table does not lie in the same address space as does the
+ 	 * mapped RAM in either case.  So we will need to create a special
+diff --git a/nuttx/arch/arm/src/armv7-a/arm_mmu.c b/nuttx/arch/arm/src/armv7-a/arm_mmu.c
+index f82490c..5c16e48 100644
+--- a/nuttx/arch/arm/src/armv7-a/arm_mmu.c
++++ b/nuttx/arch/arm/src/armv7-a/arm_mmu.c
+@@ -94,7 +94,7 @@ void mmu_l1_setentry(uint32_t paddr, uint32_t vaddr, uint32_t mmuflags)
+ 
+   /* Invalidate the TLB cache associated with virtual address range */
+ 
+-  mmu_invalidate_region(vaddr, 1024*1024);
++//  mmu_invalidate_region(vaddr, 1024*1024);
+ }
+ #endif
+ 
+diff --git a/nuttx/arch/arm/src/common/up_internal.h b/nuttx/arch/arm/src/common/up_internal.h
+index eb3ca89..8310d8a 100644
+--- a/nuttx/arch/arm/src/common/up_internal.h
++++ b/nuttx/arch/arm/src/common/up_internal.h
+@@ -60,7 +60,7 @@
+ #undef  CONFIG_SUPPRESS_INTERRUPTS    /* DEFINED: Do not enable interrupts */
+ #undef  CONFIG_SUPPRESS_TIMER_INTS    /* DEFINED: No timer */
+ #undef  CONFIG_SUPPRESS_SERIAL_INTS   /* DEFINED: Console will poll */
+-#undef  CONFIG_SUPPRESS_UART_CONFIG   /* DEFINED: Do not reconfig UART */
++#define  CONFIG_SUPPRESS_UART_CONFIG  1 /* DEFINED: Do not reconfig UART */
+ #undef  CONFIG_DUMP_ON_EXIT           /* DEFINED: Dump task state on exit */
+ 
+ /* Determine which (if any) console driver to use.  If a console is enabled

configs/sama5d3x-ek/README.txt

@@ -2577,13 +2577,7 @@ Configurations
   2. Unless stated otherwise, all configurations generate console
      output on UART0 (J3).
 
-  3. Unless otherwise stated, the configurations are setup for
+  3. All of these configurations use the Code Sourcery for Windows toolchain
-     Linux (or any other POSIX environment like Cygwin under Windows):
-
-     Build Setup:
-       CONFIG_HOST_LINUX=y   : Linux or other POSIX environment
-
-  4. All of these configurations use the Code Sourcery for Windows toolchain
      (unless stated otherwise in the description of the configuration).  That
      toolchain selection can easily be reconfigured using 'make menuconfig'.
      Here are the relevant current settings: