From 75c3f4a25c9a1250ecba2eb40dbe1c4f16087184 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Wed, 30 Mar 2016 11:19:16 +0200 Subject: [PATCH] AM335x: Disable watchdog on 'reset halt' At least on my (phyCORE-AM335X) system, the AM335x watchdog needs to be disabled to use OpenOCD for more than 6.5 seconds after reset. Change-Id: I3d883a9f572b0ccb92f9864853a00c372e39d7f2 Signed-off-by: Harald Welte Reviewed-on: http://openocd.zylin.com/3391 Tested-by: jenkins Reviewed-by: Tom Rini Reviewed-by: Paul Fertser --- tcl/target/am335x.cfg | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/tcl/target/am335x.cfg b/tcl/target/am335x.cfg index 74096151e..3ca196b11 100644 --- a/tcl/target/am335x.cfg +++ b/tcl/target/am335x.cfg @@ -76,3 +76,35 @@ target create $_TARGETNAME cortex_a -chain-position $_CHIPNAME.dap -dbgbase 0x80 # SRAM: 64K at 0x4030.0000; use the first 16K $_TARGETNAME configure -work-area-phys 0x40300000 -work-area-size 0x4000 + + +# when putting the target into 'reset halt', we need to disable the watchdog as +# it would otherwise trigger while we're in JTAG +# FIXME: unify with target/am437x.cfg +source [find mem_helper.tcl] +set WDT1_BASE_ADDR 0x44e35000 +set WDT1_W_PEND_WSPR [expr $WDT1_BASE_ADDR + 0x0034] +set WDT1_WSPR [expr $WDT1_BASE_ADDR + 0x0048] +proc disable_watchdog { } { + global WDT1_WSPR + global WDT1_W_PEND_WSPR + global _TARGETNAME + + set curstate [$_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-end { disable_watchdog }