mpc5200: a4m2k: Implement custom "dynamic" watchdog support

This patch adds a custom U-Boot command "wdogtoggle" which enables the
external hardware watchdog toggling via an GPIO pin on the a4m2k
board. After issuing this commands, the watchdog will be serviced
by U-Boot so that the user can use all U-Boot commands from the
prompt.

Signed-off-by: Stefan Roese <sr@denx.de>

diff --git a/board/a3m071/a3m071.c b/board/a3m071/a3m071.c
index 0a86e9abc1ec1b029b7599edef6f72239236e614..0f9f883e9089e83ca5f9b1b939f455e41b4a0b8a 100644 (file)
--- a/board/a3m071/a3m071.c
+++ b/board/a3m071/a3m071.c
@@ -255,7 +255,7 @@ void spl_board_init(void)
         * MPC5XXX_WU_GPIO_DIR direction is already 0 (INPUT)
         * set bit 0(msb) to 1
         */
-       setbits_be32((void *)MPC5XXX_WU_GPIO_ENABLE, 1 << (31 - 0));
+       setbits_be32((void *)MPC5XXX_WU_GPIO_ENABLE, CONFIG_WDOG_GPIO_PIN);
 
 #if defined(CONFIG_A4M2K)
        /* Setup USB[x] as MPCDiag[0..3] GPIO outputs */
@@ -410,3 +410,57 @@ int spl_start_uboot(void)
        return 1;
 }
 #endif
+
+#if defined(CONFIG_HW_WATCHDOG)
+static int watchdog_toggle;
+
+void hw_watchdog_reset(void)
+{
+       int val;
+
+       /*
+        * Check if watchdog is enabled via user command
+        */
+       if ((gd->flags & GD_FLG_RELOC) && watchdog_toggle) {
+               /* Set direction to output */
+               setbits_be32((void *)MPC5XXX_WU_GPIO_DIR, CONFIG_WDOG_GPIO_PIN);
+
+               /*
+                * Toggle watchdog output
+                */
+               val = (in_be32((void *)MPC5XXX_WU_GPIO_DATA_O) &
+                      CONFIG_WDOG_GPIO_PIN);
+               if (val) {
+                       clrbits_be32((void *)MPC5XXX_WU_GPIO_DATA_O,
+                                    CONFIG_WDOG_GPIO_PIN);
+               } else {
+                       setbits_be32((void *)MPC5XXX_WU_GPIO_DATA_O,
+                                    CONFIG_WDOG_GPIO_PIN);
+               }
+       }
+}
+
+int do_wdog_toggle(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+       if (argc != 2)
+               goto usage;
+
+       if (strncmp(argv[1], "on", 2) == 0)
+               watchdog_toggle = 1;
+       else if (strncmp(argv[1], "off", 3) == 0)
+               watchdog_toggle = 0;
+       else
+               goto usage;
+
+       return 0;
+usage:
+       printf("Usage: wdogtoggle %s\n", cmdtp->usage);
+       return 1;
+}
+
+U_BOOT_CMD(
+       wdogtoggle, CONFIG_SYS_MAXARGS, 2, do_wdog_toggle,
+       "toggle GPIO pin to service watchdog",
+       "[on/off] - Switch watchdog toggling via GPIO pin on/off"
+);
+#endif

diff --git a/include/configs/a3m071.h b/include/configs/a3m071.h
index d8559d805ac4b0d0951c16e379b03276e811261c..13f32267e925e5dde83214b53412163124960d5b 100644 (file)
--- a/include/configs/a3m071.h
+++ b/include/configs/a3m071.h
@@ -166,6 +166,11 @@
 #define CONFIG_SYS_GPS_PORT_CONFIG_2   0x1005C005
 #endif
 
+#define CONFIG_WDOG_GPIO_PIN           GPIO_WKUP_7
+#if defined(CONFIG_A4M2K) && !defined(CONFIG_SPL_BUILD)
+#define CONFIG_HW_WATCHDOG             /* Use external HW-Watchdog     */
+#endif
+
 /*
  * Configuration matrix
  *                        MSB                          LSB