# SPDX-License-Identifier: GPL-2.0-or-later

# TI/Luminary Stellaris LM3S chip family

# Some devices have errata in returning their device class.
# DEVICECLASS is provided as a manual override
# Manual setting of a device class of 0xff is not allowed

global _DEVICECLASS

if { [info exists DEVICECLASS] } {
   set _DEVICECLASS $DEVICECLASS
} else {
   set _DEVICECLASS 0xff
}

# Luminary chips support both JTAG and SWD transports.
# Adapt based on what transport is active.
source [find target/swj-dp.tcl]

# For now we ignore the SPI and UART options, which
# are usable only for ISP style initial flash programming.

if { [info exists CHIPNAME] } {
   set _CHIPNAME $CHIPNAME
} else {
   set _CHIPNAME lm3s
}

# CPU TAP ID 0x1ba00477 for early Sandstorm parts
# CPU TAP ID 0x2ba00477 for later SandStorm parts, e.g. lm3s811 Rev C2
# CPU TAP ID 0x3ba00477 for Cortex-M3 r1p2 (on Fury, DustDevil)
# CPU TAP ID 0x4ba00477 for Cortex-M3 r2p0 (on Tempest, Firestorm)
# CPU TAP ID 0x4ba00477 for Cortex-M4 r0p1 (on Blizzard)
# ... we'll ignore the JTAG version field, rather than list every
# chip revision that turns up.
if { [info exists CPUTAPID] } {
   set _CPUTAPID $CPUTAPID
} else {
   set _CPUTAPID 0x0ba00477
}

# SWD DAP, and JTAG TAP, take same params for now;
# ... even though SWD ignores all except TAPID, and
# JTAG shouldn't need anything more then irlen. (and TAPID).
swj_newdap $_CHIPNAME cpu -irlen 4 -irmask 0xf \
    -expected-id $_CPUTAPID -ignore-version
dap create $_CHIPNAME.dap -chain-position $_CHIPNAME.cpu

if { [info exists WORKAREASIZE] } {
   set _WORKAREASIZE $WORKAREASIZE
} else {
   # default to 2K working area
   set _WORKAREASIZE 0x800
}

set _TARGETNAME $_CHIPNAME.cpu
target create $_TARGETNAME cortex_m -dap $_CHIPNAME.dap

# 8K working area at base of ram, not backed up
#
# NOTE: you may need or want to reconfigure the work area;
# some parts have just 6K, and you may want to use other
# addresses (at end of mem not beginning) or back it up.
$_TARGETNAME configure -work-area-phys 0x20000000 -work-area-size $_WORKAREASIZE

# JTAG speed ... slow enough to work with a 12 MHz RC oscillator;
# LM3S parts don't support RTCK
#
# NOTE: this may be increased by a reset-init handler, after it
# configures and enables the PLL.  Or you might need to decrease
# this, if you're using a slower clock.
adapter speed 500

source [find mem_helper.tcl]

proc reset_peripherals {family} {

	source [find chip/ti/lm3s/lm3s.tcl]

	echo "Resetting Core Peripherals"

	# Disable the PLL and the system clock divider (nop if disabled)
	mmw $SYSCTL_RCC 0 $SYSCTL_RCC_USESYSDIV
	mmw $SYSCTL_RCC2 $SYSCTL_RCC2_BYPASS2 0

	# RCC and RCC2 to their reset values
	mww $SYSCTL_RCC [expr {0x078e3ad0 | ([mrw $SYSCTL_RCC] & $SYSCTL_RCC_MOSCDIS)}]
	mww $SYSCTL_RCC2 0x07806810
	mww $SYSCTL_RCC 0x078e3ad1

	# Reset the deep sleep clock configuration register
	mww $SYSCTL_DSLPCLKCFG 0x07800000

	# Reset the clock gating registers
	mww $SYSCTL_RCGC0 0x00000040
	mww $SYSCTL_RCGC1 0
	mww $SYSCTL_RCGC2 0
	mww $SYSCTL_SCGC0 0x00000040
	mww $SYSCTL_SCGC1 0
	mww $SYSCTL_SCGC2 0
	mww $SYSCTL_DCGC0 0x00000040
	mww $SYSCTL_DCGC1 0
	mww $SYSCTL_DCGC2 0

	# Reset the remaining SysCtl registers
	mww $SYSCTL_PBORCTL 0
	mww $SYSCTL_IMC 0
	mww $SYSCTL_GPIOHBCTL 0
	mww $SYSCTL_MOSCCTL 0
	mww $SYSCTL_PIOSCCAL 0
	mww $SYSCTL_I2SMCLKCFG 0

	# Reset the peripherals
	mww $SYSCTL_SRCR0 0xffffffff
	mww $SYSCTL_SRCR1 0xffffffff
	mww $SYSCTL_SRCR2 0xffffffff
	mww $SYSCTL_SRCR0 0
	mww $SYSCTL_SRCR1 0
	mww $SYSCTL_SRCR2 0

	# Clear any pending SysCtl interrupts
	mww $SYSCTL_MISC 0xffffffff

	# Wait for any pending flash operations to complete
	while {[expr {[mrw $FLASH_FMC] & 0xffff}] != 0} { sleep 1 }
	while {[expr {[mrw $FLASH_FMC2] & 0xffff}] != 0} { sleep 1 }

	# Reset the flash controller registers
	mww $FLASH_FMA 0
	mww $FLASH_FCIM 0
	mww $FLASH_FCMISC 0xffffffff
	mww $FLASH_FWBVAL 0
}

$_TARGETNAME configure -event reset-start {
	adapter speed 500

	#
	# When nRST is asserted on most Stellaris devices, it clears some of
	# the debug state.  The ARMv7M and Cortex-M3 TRMs say that's wrong;
	# and OpenOCD depends on those TRMs.  So we won't use SRST on those
	# chips.  (Only power-on reset should affect debug state, beyond a
	# few specified bits; not the chip's nRST input, wired to SRST.)
	#
	# REVISIT current errata specs don't seem to cover this issue.
	# Do we have more details than this email?
	#   https://lists.berlios.de/pipermail
	#	/openocd-development/2008-August/003065.html
	#

	global _DEVICECLASS

	if {$_DEVICECLASS != 0xff} {
	   set device_class $_DEVICECLASS
	} else {
	   set device_class [expr {([mrw 0x400fe000] >> 16) & 0xff}]
	}

	if {$device_class == 0 || $device_class == 1 ||
		$device_class == 3 || $device_class == 5 || $device_class == 0xa} {
		if {![using_hla]} {
		   # Sandstorm, Fury, DustDevil, Blizzard and Snowflake are able to use NVIC SYSRESETREQ
		   cortex_m reset_config sysresetreq
		}
	} else {
		if {![using_hla]} {
		   # Tempest and Firestorm default to using NVIC VECTRESET
		   # peripherals will need resetting manually, see proc reset_peripherals
		   cortex_m reset_config vectreset
		}
		# reset peripherals, based on code in
		# http://www.ti.com/lit/er/spmz573a/spmz573a.pdf
		reset_peripherals $device_class
	}
}

# flash configuration ... autodetects sizes, autoprobed
flash bank $_CHIPNAME.flash stellaris 0 0 0 0 $_TARGETNAME