util/bincfg: Add DDR4 SPD spec

Additionally provide a simple script for decoding spd hex files using bincfg.

BUG=b:148561711
TEST=Decoded spd files in zork
BRANCH=None

Change-Id: Ic62868d59e075fd6816d7be55cc935e3e3f82499
Signed-off-by: Rob Barnes <robbarnes@google.com>
Reviewed-on: https://chromium-review.googlesource.com/2067697
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/39621
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michael Niewöhner

2 files changed, 78 insertions, 0 deletions

diff --git a/util/scripts/decode_spd.sh b/util/scripts/decode_spd.sh
new file mode 100755
index 0000000000..9ab9fa30cf
--- /dev/null
+++ b/util/scripts/decode_spd.sh
@@ -0,0 +1,76 @@
+#!/bin/bash
+#
+# This file is part of the coreboot project.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; version 2 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+#
+# Parses spd hex files and outputs the contents in various formats
+#
+#
+# Outputs csv, set, and json in same folder as SPD_HEX_FILE
+#
+# Example:
+# 	decode_spd.sh ../../src/mainboard/google/zork/spd/micron-MT40A512M16TB-062E-J.spd.hex
+#
+# Outputs ../../src/mainboard/google/zork/spd/micron-MT40A512M16TB-062E-J.spd.{json|csv|set}
+#
+# TODO: This script assumes bincfg binary is at ../bincfg/bincfg (which is the
+#	result of running the bincfg make), and the specs are at
+#	../bincfg/*.spec. This dependency should be made more resilliant and
+#	configurable.
+
+set -e
+
+function read8 () {
+	echo $(( 16#$(xxd -s "${2}" -l 1 -p "${1}") ))
+}
+
+for file in "$@"
+do
+	bintmp=$(mktemp)
+	outfile="${file%.hex}.set"
+
+	echo "Decoding ${file}, outputting to ${outfile}"
+
+	grep -v '^#' "${file}" | xxd -r -p - "${bintmp}"
+	dram_type=$(read8 "${bintmp}" 2)
+	if [ ! "${dram_type}" -eq 12 ]
+	then
+		#TODO: Handle other dram types
+		printf "Error: Expecting dram4 (12), got %d\n" "${dram_type}"
+		continue
+	fi
+
+	revision=$(read8 "${bintmp}" 1)
+	if [ ! "${revision}" -eq $((0x13)) ]
+	then
+		printf "Warning: Expecting revision 0x13, got 0x%x.\n" "${revision}"
+	fi
+
+	module_type=$(read8 "${bintmp}" 3)
+	case "${module_type}" in
+	1) # RDIMM
+		spec="../bincfg/ddr4_registered_spd_512.spec"
+	;;
+	2 | 3) #UDIMM | SO-DIMM
+		spec="../bincfg/ddr4_unbuffered_spd_512.spec"
+	;;
+	* )
+		printf "Error: Unhandled module type %d.\n" "${module_type}"
+	;;
+	esac
+
+	../bincfg/bincfg -d "${spec}" "${bintmp}" "${outfile}"
+	grep -v '^#' "${outfile}" | sed -e 's/ = \([^,]\+\)/: "\1"/g' \
+		> "${file%.hex}.json"
+	grep -v -e '^#' -e '^{' -e '^}' "${outfile}" | sed -e 's/=/,/g' \
+		> "${file%.hex}.csv"
+done
diff --git a/util/scripts/description.md b/util/scripts/description.md
index 1f4e7df042..a08771d48d 100644
--- a/util/scripts/description.md
+++ b/util/scripts/description.md
@@ -3,6 +3,8 @@ __scripts__
               line `Bash`
   * _cross-repo-cherrypick_ - Pull in patches from another tree from a
                               gerrit repository. `Shell`
+  * _decode_spd.sh_ - Decodes Serial Presence Detect (SPD) files into
+                      various human readable formats.
   * _dts-to-fmd.sh_ -Converts a depthcharge fmap.dts into an fmaptool
                      compatible .fmd format `Bash`
   * _find-unused-kconfig-symbols.sh_ - Points out Kconfig variables