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Diffstat (limited to 'util/spd_tools/ddr4/README.md')
| -rw-r--r-- | util/spd_tools/ddr4/README.md | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/util/spd_tools/ddr4/README.md b/util/spd_tools/ddr4/README.md index 81ab97a80a..646d937d9b 100644 --- a/util/spd_tools/ddr4/README.md +++ b/util/spd_tools/ddr4/README.md @@ -16,8 +16,8 @@ by the board. SPD files. * gen_part_id.go: Allocates DRAM strap IDs for different DDR4 - memory parts used by the board. Takes as input list of memory parts - used by the board (with one memory part on each line) and the SPD + memory parts used by the board. Takes as input a list of memory parts + used (in CSV format) by the board with optional fixed ids and the SPD manifest file generated by gen_spd.go. Generates Makefile.inc for integrating the generated SPD files in the coreboot build. @@ -192,12 +192,29 @@ This program takes as input: * Pointer to directory where the SPD files and the manifest file `ddr4_spd_manifest.generated.txt` (in CSV format) are placed by gen_spd.go -* File containing list of memory parts used by the board. Each line of - the file is supposed to contain one memory part `name` as present in - the global list of memory parts provided to gen_spd.go +* CSV file containing list of memory parts used by the board and optional + fixed id. Each line of the file is supposed to contain one memory part `name` + as present in the global list of memory parts provided to gen_spd.go. + Optionally a fixed id may also be assigned to the part if required. + NOTE: Only assign a fixed ID if required for legacy reasons. + * Pointer to directory where the generated Makefile.inc should be placed by the tool. +Sample input (mem_parts_used_file.txt): +``` +K4AAG165WA-BCWE,1 +MT40A512M16TB-062E:J +MT40A1G16KD-062E:E +K4A8G165WC-BCWE +H5AN8G6NDJR-XNC,8 +H5ANAG6NCMR-XNC +``` +NOTE: This will ensure SPDs compatible with K4AAG165WA-BCWE and H5AN8G6NDJR-XNC +are assigned to ID 1 and 8 respectively. All other memory parts will be +assigned to the first compatible ID. Assigning fixed IDs may result in +duplicate SPD entries or gaps in the ID mapping. + ### Output This program provides the following: @@ -227,8 +244,11 @@ Sample Makefile.inc: SPD_SOURCES = SPD_SOURCES += ddr4-spd-1.hex # ID = 0(0b0000) Parts = MEMORY_PART_A SPD_SOURCES += ddr4-spd-2.hex # ID = 1(0b0001) Parts = MEMORY_PART_B, MEMORY_PART_D +SPD_SOURCES += ddr4-spd-empty.hex # ID = 2(0b0010) SPD_SOURCES += ddr4-spd-3.hex # ID = 2(0b0010) Parts = MEMORY_PART_C ``` +NOTE: Empty entries may be required if there is a gap created by a memory part +with a fixed id. ### Note of caution |