From d85a0a6a0c6a73fbccf2dbdce3c25280d9ff8522 Mon Sep 17 00:00:00 2001
From: Felipe Balbi <balbi@ti.com>
Date: Sun, 15 Mar 2015 23:15:15 -0500
Subject: [PATCH] tcl: am437x: disable watchdog on reset-end

sometimes, watchdog might be left running and
it could expire in the middle of a debug session,
to prevent that, just make sure to disable watchdog
on reset-end if current state is 'halted'.

Change-Id: Ib4f2a2321cba17cd8c56ca3ae63114a563a6de90
Tested-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-on: http://openocd.zylin.com/2615
Tested-by: jenkins
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Paul Fertser <fercerpav@gmail.com>
---
 tcl/target/am437x.cfg | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/tcl/target/am437x.cfg b/tcl/target/am437x.cfg
index d7d47530..ee62ef92 100644
--- a/tcl/target/am437x.cfg
+++ b/tcl/target/am437x.cfg
@@ -1,4 +1,5 @@
 source [find target/icepick.cfg]
+source [find mem_helper.tcl]
 
 ###############################################################################
 ##				AM437x Registers			     ##
@@ -481,3 +482,31 @@ target create $_TARGETNAME cortex_a -chain-position $_CHIPNAME.dap -dbgbase 0x80
 
 # SRAM: 256K at 0x4030.0000
 $_TARGETNAME configure -work-area-phys 0x40300000 -work-area-size 0x40000
+
+# Disables watchdog timer after reset otherwise board won't stay in
+# halted state.
+proc disable_watchdog { } {
+	global WDT1_WSPR
+	global WDT1_W_PEND_WSPR
+	global _TARGETNAME
+
+	set curstate [$_TARGETNAME curstate]
+
+	if { [string compare $curstate halted] == 0 } {
+		set WDT_DISABLE_SEQ1	0xaaaa
+		set WDT_DISABLE_SEQ2	0x5555
+
+		mww phys $WDT1_WSPR $WDT_DISABLE_SEQ1
+
+		# Empty body to make sure this executes as fast as possible.
+		# We don't want any delays here otherwise romcode might start
+		# executing and end up changing state of certain IPs.
+		while { [expr [mrw $WDT1_W_PEND_WSPR] & 0x10] } { }
+
+		mww phys $WDT1_WSPR $WDT_DISABLE_SEQ2
+		while { [expr [mrw $WDT1_W_PEND_WSPR] & 0x10] } { }
+	}
+}
+
+$_TARGETNAME configure -event reset-start { adapter_khz 1000 }
+$_TARGETNAME configure -event reset-end { disable_watchdog }
-- 
2.39.5