[PATCH] board: freescale: p1_p2_rdb_pc: Delete watchdog max6370 node in load_default mode

[Pali Rohár]

CPLD in load_default mode ignores watchdog reset signal. It does not reset
board when watchdog triggers reset signal.

Detect load_default mode by GPIO7 - LOAD_DEFAULT_N and delete watchdog
max6370 node from device to prevent registering driver for non-working
watchdog.

Signed-off-by: Pali Rohár <pali at kernel.org>
---
 board/freescale/p1_p2_rdb_pc/p1_p2_rdb_pc.c | 28 +++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/board/freescale/p1_p2_rdb_pc/p1_p2_rdb_pc.c b/board/freescale/p1_p2_rdb_pc/p1_p2_rdb_pc.c
index a71952dcf399..06cab729e4ab 100644
--- a/board/freescale/p1_p2_rdb_pc/p1_p2_rdb_pc.c
+++ b/board/freescale/p1_p2_rdb_pc/p1_p2_rdb_pc.c
@@ -368,6 +368,24 @@ int board_eth_init(struct bd_info *bis)
 }
 #endif
 
+#if defined(CONFIG_OF_BOARD_SETUP) || defined(CONFIG_OF_BOARD_FIXUP)
+static void fix_max6370_watchdog(void *blob)
+{
+	int off = fdt_node_offset_by_compatible(blob, -1, "maxim,max6370");
+	ccsr_gpio_t *pgpio = (void *)(CONFIG_SYS_MPC85xx_GPIO_ADDR);
+	u32 gpioval = in_be32(&pgpio->gpdat);
+
+	/*
+	 * Delete watchdog max6370 node in load_default mode (detected by
+	 * GPIO7 - LOAD_DEFAULT_N) because CPLD in load_default mode ignores
+	 * watchdog reset signal. CPLD in load_default mode does not reset
+	 * board when watchdog triggers reset signal.
+	 */
+	if (!(gpioval & BIT(31-7)) && off >= 0)
+		fdt_del_node(blob, off);
+}
+#endif
+
 #ifdef CONFIG_OF_BOARD_SETUP
 int ft_board_setup(void *blob, struct bd_info *bd)
 {
@@ -393,6 +411,8 @@ int ft_board_setup(void *blob, struct bd_info *bd)
 			sizeof("okay"), 0);
 #endif
 
+	fix_max6370_watchdog(blob);
+
 #if defined(CONFIG_HAS_FSL_DR_USB)
 	fsl_fdt_fixup_dr_usb(blob, bd);
 #endif
@@ -444,3 +464,11 @@ int ft_board_setup(void *blob, struct bd_info *bd)
 	return 0;
 }
 #endif
+
+#ifdef CONFIG_OF_BOARD_FIXUP
+int board_fix_fdt(void *blob)
+{
+	fix_max6370_watchdog(blob);
+	return 0;
+}
+#endif
-- 
2.20.1