tcl/interface: support for Raspberry Pi 5

Make sure raspberrypi-native.cfg cannot be used on RPi5.

Add raspberrypi5-gpiod.cfg which uses linuxgpiod adapter driver.
Issue a warning if PCIe is in power save mode.

While on it, re-format warnings issued from Tcl to look similar
to LOG_WARNING() output.

Change-Id: If19b0350bd5fff83d9a0c65999e33b161fb6957a
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: https://review.openocd.org/c/openocd/+/8333
Tested-by: jenkins
Reviewed-by: Jonathan Bell <jonathan@raspberrypi.com>

tcl/interface/raspberrypi-gpio-connector.cfg

@@ -10,6 +10,12 @@
 # Do not forget the GND connection, e.g. pin 20 of the GPIO header.
 #
 
+if { [info exists GPIO_CHIP] } {
+    set _GPIO_CHIP $GPIO_CHIP
+} else {
+    set _GPIO_CHIP 0
+}
+
 # GPIO 25 (pin 22) previously used for TMS/SWDIO is pulled-down by default.
 # The JTAG/SWD specification requires pull-up at the target board
 # for either signal. Connecting the signal pulled-up on the target
@@ -19,23 +25,23 @@ echo "Warn : TMS/SWDIO moved to GPIO 8 (pin 24). Check the wiring please!"
 
 # Each of the JTAG lines need a gpio number set: tck tms tdi tdo
 # Header pin numbers: 23 24 19 21
-adapter gpio tck -chip 0 11
-adapter gpio tms -chip 0 8
-adapter gpio tdi -chip 0 10
-adapter gpio tdo -chip 0 9
+adapter gpio tck -chip $_GPIO_CHIP 11
+adapter gpio tms -chip $_GPIO_CHIP 8
+adapter gpio tdi -chip $_GPIO_CHIP 10
+adapter gpio tdo -chip $_GPIO_CHIP 9
 
 # Each of the SWD lines need a gpio number set: swclk swdio
 # Header pin numbers: 23 24
-adapter gpio swclk -chip 0 11
-adapter gpio swdio -chip 0 8
+adapter gpio swclk -chip $_GPIO_CHIP 11
+adapter gpio swdio -chip $_GPIO_CHIP 8
 
 # If you define trst or srst, use appropriate reset_config
 # Header pin numbers: TRST - 26, SRST - 18
 
-# adapter gpio trst -chip 0 7
+# adapter gpio trst -chip $_GPIO_CHIP 7
 # reset_config trst_only
 
-# adapter gpio srst -chip 0 24
+# adapter gpio srst -chip $_GPIO_CHIP 24
 # reset_config srst_only srst_push_pull
 
 # or if you have both connected,

tcl/interface/raspberrypi-native.cfg

@@ -37,9 +37,9 @@ proc get_max_cpu_clock { default } {
 		return $clock
 	}
 
-	echo "WARNING: Host CPU clock unknown."
-	echo "WARNING: Using the highest possible value $default kHz as a safe default."
-	echo "WARNING: Expect JTAG/SWD clock significantly slower than requested."
+	echo "Warn : Host CPU clock unknown."
+	echo "Warn : Using the highest possible value $default kHz as a safe default."
+	echo "Warn : Expect JTAG/SWD clock significantly slower than requested."
 
 	return $default
 }
@@ -56,9 +56,13 @@ if {[string match *bcm2711* $compat]} {
 } elseif {[string match *bcm2835* $compat] || [string match *bcm2708* $compat]} {
 	set clocks_per_timing_loop 6
 	set speed_offset 32
+} elseif {[string match *bcm2712* $compat]} {
+	echo "Error: Raspberrypi Pi 5 has moved GPIOs to PCIe connected RP1 chip."
+	echo "Error: Native GPIO handling is not supported, use 'raspberrypi5-gpiod.cfg'"
+	shutdown
 } else {
 	set speed_offset 32
-	echo "WARNING: Unknown type of the host SoC. Expect JTAG/SWD clock slower than requested."
+	echo "Warn : Unknown type of the host SoC. Expect JTAG/SWD clock slower than requested."
 }
 
 set clock [get_max_cpu_clock 2000000]

tcl/interface/raspberrypi5-gpiod.cfg

@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+# Config for Raspberry Pi 5 used as a bitbang adapter.
+# https://www.raspberrypi.com/documentation/computers/raspberry-pi.html
+
+# Raspberry Pi 5 is not compatible with bcm2835gpio native GPIO driver.
+# The linuxgpiod driver without configurable adapter speed runs at approximately
+# 800 kHz (SWD writes) and 360 kHz (SWD reads)
+
+adapter driver linuxgpiod
+
+proc read_file { name } {
+	if {[catch {open $name r} fd]} {
+		return ""
+	}
+	set result [read $fd]
+	close $fd
+	return $result
+}
+
+set pcie_aspm [read_file /sys/module/pcie_aspm/parameters/policy]
+# escaping [ ] characters in string match pattern does not work in Jim-Tcl
+if {![string match "*<performance>*" [string map { "\[" < "\]" > } $pcie_aspm]]} {
+	echo "Warn : Switch PCIe power saving off or the first couple of pulses gets clocked as fast as 20 MHz"
+	echo "Warn : Issue 'echo performance | sudo tee /sys/module/pcie_aspm/parameters/policy'"
+}
+
+set GPIO_CHIP 4
+source [find interface/raspberrypi-gpio-connector.cfg]