configs/metro-m4: Instructions for unlocking FLASH ... which may be l…

…ethal.
PX4 · Aug 1, 2018 · 8876f9c · 8876f9c
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diff --git a/configs/metro-m4/README.txt b/configs/metro-m4/README.txt
@@ -33,6 +33,110 @@ STATUS
   2018-07-20:  Brought in the USB driver from the SAML21.  It is the same
     USB IP with only small differences.  There a a few, small open issues
     still to be resolved.
+  2018-08-01:  Hardware in hand.  Initial attempts to program the board
+    using a Segger J-Link connected via SWD were unsuccessful.  I believe
+    that the FLASH is locked.  See "Unlocking FLASH with J-Link Commander"
+    below.  Unfortunately, this seems to have rendered by board unusable.
+    Sigh.
+
+Unlocking FLASH
+===============
+
+  Options
+  -------
+  The Adafruit Metro M4 comes with a very nice bootloader resident in FLASH.
+  so we have two options:
+
+  1. Learn to play well with others.  Make NuttX coexist and work in the
+     memory partition available to it.  Or,
+  2. Be greedy, unlock the FLASH and overwrite the bootloader.
+
+  I chose to do the last one.  I used a Segger J-Link and here are the steps
+  that I took.  You can probably do these things in Atmel Studio (?) but for
+  other debug environments, you would have to come up with the solution.
+
+  Unlocking FLASH with J-Link Commander
+  -------------------------------------
+
+  1. Start J-Link Commander:
+
+      SEGGER J-Link Commander V6.32i (Compiled Jul 24 2018 15:20:49)
+      DLL version V6.32i, compiled Jul 24 2018 15:19:55
+
+      Connecting to J-Link via USB...O.K.
+      Firmware: J-Link V9 compiled Apr 20 2018 16:47:26
+      Hardware version: V9.30
+      S/N: 269303123
+      License(s): FlashBP, GDB
+      OEM: SEGGER-EDU
+      VTref=3.296V
+
+
+      Type "connect" to establish a target connection, '?' for help
+      J-Link>con
+      Please specify device / core. <Default>: ATSAMD51P19
+      Type '?' for selection dialog
+      Device>ATSAMD51P19
+      Please specify target interface:
+        J) JTAG (Default)
+        S) SWD
+      TIF>S
+      Specify target interface speed [kHz]. <Default>: 4000 kHz
+      Speed>
+      Device "ATSAMD51P19" selected.
+
+
+      Connecting to target via SWD
+      Found SW-DP with ID 0x2BA01477
+      Scanning AP map to find all available APs
+      ...etc. ...
+
+  2. Look at The NVM "user page" memory at address 0x00804000:
+
+       J-Link>mem8 804000, 10
+       00804000 = 39 92 9A F6 80 FF EC AE FF FF FF FF FF FF FF FF
+
+     The field NVM BOOT (also called BOOTPROT) is the field that locks the
+     lower part of FLASH to support the boot loader.  This is bits 26-29
+     of the NVM user page:
+
+       J-Link>mem32 804000, 1
+       00804000 = F69A9239
+
+    In binary 11|11 01|10 1001 1010  1001 0010 0011 1001, so NVM Boot 1101.
+    To unlock the FLASH memory reserved for the bootloader, we need to
+    change this field to 111 so that:
+
+      1111 01|11 11|01 1010  1001 0010 0011 1001 = F7da9239, or
+      00804000 = 39 92 DA F7 80 FF EC AE FF FF FF FF FF FF FF FF
+
+    is read.
+
+  3. Modify the NVM "user page"
+
+    I did this using the instructions for the SAMD21 found at
+
+      https://roamingthings.de/use-j-link-to-change-the-boot-loader-protection-of-a-sam-d21/
+
+    We will need to create a small Motorola S-REC file to write new values
+    into NVM.  See https://en.m.wikipedia.org/wiki/SREC_(file_format) for a
+    description of the Motorola SREC format.
+
+    I wrote a small program at configs/metro-m4-scripts/nvm.c that will
+    generate this Motorola SREC file with the correct checksum.  The file at
+    configs/metro-m4-scripts/nvm.c is the output of that program.
+
+      J-Link>mem8 804000,10
+      00804000 = 39 92 9A F6 80 FF EC AE FF FF FF FF FF FF FF FF
+      J-Link>loadfile D:\Spuda\Documents\projects\nuttx\master\nuttx\configs\metro-m4\scripts\nvm.srec
+      Downloading file [D:\Spuda\Documents\projects\nuttx\master\nuttx\configs\metro-m4\scripts\nvm.srec]...
+      J-Link: Flash download: Bank 1 @ 0x00804000: 1 range affected (16 bytes)
+      J-Link: Flash download: Total time needed: 0.089s (Prepare: 0.035s, Compare: 0.011s, Erase: 0.000s, Program: 0.019s, Verify: 0.011s, Restore: 0.011s)
+      O.K.
+      J-Link>mem8 804000,10
+      00804000 = 39 92 9A FE 80 FF EC AE FF FF FF FF FF FF FF FF
+
+    You will, of course, have to change the path as appropriate for your system.
 
 Serial Console
 ==============

diff --git a/configs/metro-m4/nsh/defconfig b/configs/metro-m4/nsh/defconfig
@@ -16,6 +16,7 @@ CONFIG_HAVE_CXX=y
 CONFIG_HAVE_CXXINITIALIZE=y
 CONFIG_MAX_TASKS=16
 CONFIG_MAX_WDOGPARMS=2
+CONFIG_MOTOROLA_SREC=y
 CONFIG_NFILE_DESCRIPTORS=8
 CONFIG_NFILE_STREAMS=8
 CONFIG_NSH_BUILTIN_APPS=y
@@ -28,7 +29,6 @@ CONFIG_PREALLOC_WDOGS=4
 CONFIG_PTHREAD_STACK_DEFAULT=1536
 CONFIG_RAM_SIZE=32768
 CONFIG_RAM_START=0x20000000
-CONFIG_RAW_BINARY=y
 CONFIG_RR_INTERVAL=200
 CONFIG_SAMD5E5_EIC=y
 CONFIG_SAMD5E5_SERCOM3=y

diff --git a/configs/metro-m4/scripts/nvm.c b/configs/metro-m4/scripts/nvm.c
@@ -0,0 +1,28 @@
+#include <stdio.h>
+#include <stdint.h>
+
+const uint8_t nvm[20] =
+{
+  0x14,                                           /* Count 20 bytes */
+  0x80, 0x40, 0x00,                               /* 24-address : 804000 */
+  0x39, 0x92, 0x9a, 0xfe, 0x80, 0xff, 0xec, 0xae, /* 16-bytes of NVM data */
+  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
+};
+
+int main(int argc, char **argv)
+{
+  unsigned int csum;
+  int i;
+
+  printf("S2");
+
+  for (i = 0, csum = 0; i < 20; i++)
+    {
+      csum += nvm[i];
+      printf("%02X", (unsigned int)nvm[i]);
+    }
+
+  printf("%02X\r\n", ~csum & 0xff);
+  printf("S9030000FC\r\n");
+  return 0;
+}
diff --git a/configs/metro-m4/scripts/nvm.srec b/configs/metro-m4/scripts/nvm.srec
@@ -0,0 +1,2 @@
+S21480400039929AFE80FFECAEFFFFFFFFFFFFFFFFB7
+S9030000FC
diff --git a/configs/viewtool-stm32f107/README.txt b/configs/viewtool-stm32f107/README.txt
@@ -743,15 +743,15 @@ MAX3421E Integration
     NAME   VIEWTOOL    STM32       USBHostShield-v13 DuinoFun UHS mini v2.0
     ------ ----------- ----------- ------------------ ----------------------
     CS#    J8  Pin  6  PB12/NSS2   D10                SS
-    SCK    J8  Pin  5  PB13/SCK2   D13                MOSI (label wrong)
+    SCK    J8  Pin  5  PB13/SCK2   D13                CLK (label MOSI)
     MISO   J8  Pin  3  PB14/MISO2  D12                MISO
-    MOSI   J8  Pin  4  PB15/MOSI2  D11                CLK (label wrong)
+    MOSI   J8  Pin  4  PB15/MOSI2  D11                MOSI (label CLK)
     INT#   J18 Pin 10  PA0         D9                 INT
     RST#   J18 Pin  8  PA1         D7                 MAX_RST
     GPX                            D8                 GPX
     VBUS   J18 Pin  2  5V          VIN                V_BUS
     3.3V   J8  Pin  1              N/C                VCC
-    GND    J8  Pin  2              GND                GND
+    GND    J8  Pin  2              GND                GND (no label)
 
   5V VBUS power is also needed.  This might be directly connected to the USB
   host connector (as assumed here), or switched via additional logic.  Then
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		S21480400039929AFE80FFECAEFFFFFFFFFFFFFFFFB7
		S9030000FC