summaryrefslogtreecommitdiff
path: root/util/spd_tools/README.md
diff options
context:
space:
mode:
authorReka Norman <rekanorman@google.com>2021-10-07 16:08:18 +1100
committerPatrick Georgi <pgeorgi@google.com>2021-11-04 10:46:07 +0000
commit2c439adb51ca8323b55d759e2a45b71a6187a9da (patch)
treeed7747b5498f6777e82eb9b4d8c648c854ff4459 /util/spd_tools/README.md
parente5be13e46bcf1a191ebff125ac4adc1854019515 (diff)
util/spd_tools: Add LP5 support for ADL
Add LP5 support to spd_tools. Currently, only Intel Alder Lake (ADL) is supported. The SPDs are generated based on a combination of: - The LPDDR5 spec JESD209-5B. - The SPD spec SPD4.1.2.M-2 (the LPDDR3/4 spec is used since JEDEC has not released an SPD spec for LPDDR5). - Intel recommendations in advisory #616599. BUG=b:201234943, b:198704251 TEST=Generate the SPD and manifests for a test part, and check that the SPD matches Intel's expectation. More details in CB:58680. Change-Id: Ic1e68d44f7c0ad64aa9904b7e1297d24bd5db56e Signed-off-by: Reka Norman <rekanorman@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/58679 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
Diffstat (limited to 'util/spd_tools/README.md')
-rw-r--r--util/spd_tools/README.md97
1 files changed, 97 insertions, 0 deletions
diff --git a/util/spd_tools/README.md b/util/spd_tools/README.md
index 5be666bde4..a422017581 100644
--- a/util/spd_tools/README.md
+++ b/util/spd_tools/README.md
@@ -8,6 +8,9 @@ The memory technologies currently supported are:
* LPDDR4x - based on the JESD209-4C spec and Intel recommendations
(docs #616599, #610202, #634730).
* DDR4 - based on the JESD79-4C and Jedec 4.1.2.L-5 R29 v103 specs.
+* LPDDR5 - based on the LPDDR5 spec JESD209-5B, the SPD spec SPD4.1.2.M-2 (the
+ LPDDR3/4 spec is used since JEDEC has not released an SPD spec for LPDDR5),
+ and Intel recommendations in advisory #616599.
There are two tools provided to assist with generating SPDs and Makefiles to
integrate into the coreboot build. These tools can also be used to allocate DRAM
@@ -292,6 +295,100 @@ string like "9 10 11 12 14".
}
```
+### LP5 attributes
+
+#### Mandatory
+
+* `densityPerDieGb`: Density per die in Gb. Valid values: `4, 6, 8, 12, 16,
+ 24, 32` Gb per die.
+
+* `diesPerPackage`: Number of physical dies in each SDRAM package. Valid
+ values: `2, 4, 8` dies per package.
+
+* `bitWidthPerChannel`: Width of each physical channel. Valid values: `8, 16`
+ bits.
+
+* `ranksPerChannel`: Number of ranks per physical channel. Valid values: `1,
+ 2`. If the channels across multiple dies share the same DQ/DQS pins but use
+ a separate CS, then ranks is 2 else it is 1.
+
+* `speedMbps`: Maximum data rate supported by the part in Mbps. Valid values:
+ `5500, 6400` Mbps.
+
+#### Optional
+
+* `trfcabNs`: Minimum Refresh Recovery Delay Time (tRFCab) for all banks in
+ nanoseconds. As per JESD209-5B, this is dependent on the density per die.
+ Default values used:
+
+ * 4 Gb : 180 ns
+ * 6 Gb : 210 ns
+ * 8 Gb : 210 ns
+ * 12 Gb: 280 ns
+ * 16 Gb: 280 ns
+ * 24 Gb: 380 ns
+ * 32 Gb: 380 ns
+
+* `trfcpbNs`: Minimum Refresh Recovery Delay Time (tRFCpb) per bank in
+ nanoseconds. As per JESD209-5B, this is dependent on the density per die.
+ Default values used:
+
+ * 4 Gb : 90 ns
+ * 6 Gb : 120 ns
+ * 8 Gb : 120 ns
+ * 12 Gb: 140 ns
+ * 16 Gb: 140 ns
+ * 24 Gb: 190 ns
+ * 32 Gb: 190 ns
+
+* `trpabMinNs`: Minimum Row Precharge Delay Time (tRPab) for all banks in
+ nanoseconds. As per JESD209-5B, this is max(21ns, 2nCK), which defaults to
+ `21 ns`.
+
+* `trppbMinNs`: Minimum Row Precharge Delay Time (tRPpb) per bank in
+ nanoseconds. As per JESD209-5B, this is max(18ns, 2nCK) which defaults to
+ `18 ns`.
+
+* `tckMinPs`: SDRAM minimum cycle time (tCKmin) value in picoseconds. LPDDR5
+ has two clocks: the command/addrees clock (CK) and the data clock (WCK).
+ They are related by the WCK:CK ratio, which can be either 4:1 or 2:1. For
+ LPDDR5, tCKmin is the CK period, which can be calculated from the
+ `speedMbps` attribute and the WCK:CK ratio as follows: `tCKmin = 1 /
+ (speedMbps / 2 / WCK:CK)`. The default values used are for a 4:1 WCK:CK
+ ratio:
+
+ * 6400 Mbps: 1250 ps
+ * 5500 Mbps: 1455 ps
+
+* `taaMinPs`: Minimum CAS Latency Time(tAAmin) in picoseconds. This value
+ defaults to nck * tCKmin, where nck is maximum CAS latency, and is
+ determined from the `speedMbps` attribute as per JESD209-5B:
+
+ * 6400 Mbps: 17
+ * 5500 Mbps: 15
+
+* `trcdMinNs`: Minimum RAS# to CAS# Delay Time (tRCDmin) in nanoseconds. As
+ per JESD209-5B, this is max(18ns, 2nCK) which defaults to `18 ns`.
+
+#### Example `memory_parts.json`
+
+```
+{
+ "parts": [
+ {
+ "name": "MT62F1G32D4DR-031 WT:B",
+ "attribs": {
+ "densityPerDieGb": 8,
+ "diesPerPackage": 4,
+ "bitWidthPerChannel": 16,
+ "ranksPerChannel": 2,
+ "speedMbps": 6400
+ }
+ },
+ ]
+}
+```
+
### Output
The `spd_gen` tool generates the directory structure shown below. The inputs to