Re: [PATCH 2/3] hwmon: (peci/dimmtemp) add Intel Emerald Rapids platform support

From: Paul Menzel

Date: Tue Oct 07 2025 - 04:26:43 EST


Dear Ivan,


Thank you for your patch.

Am 06.10.25 um 23:53 schrieb Ivan Mikhaylov:
Extend the functionality of hwmon (peci/dimmtemp) for Emerald Rapids
platform.

The patch has been tested on a 5S system with 16 DIMMs installed.

What is 5S? 5 sockets? (Probably not.)

Verified read of DIMM temperature thresholds & temperature.

Also paste the output?

Using Sapphire's callbacks about getting thresholds because it's same
platform/socket.

Signed-off-by: Ivan Mikhaylov <fr0st61te@xxxxxxxxx>
---
drivers/hwmon/peci/dimmtemp.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)

diff --git a/drivers/hwmon/peci/dimmtemp.c b/drivers/hwmon/peci/dimmtemp.c
index fbe82d9852e0..a281476c7a31 100644
--- a/drivers/hwmon/peci/dimmtemp.c
+++ b/drivers/hwmon/peci/dimmtemp.c
@@ -32,6 +32,8 @@
#define DIMM_IDX_MAX_ON_ICXD 2
#define CHAN_RANK_MAX_ON_SPR 8
#define DIMM_IDX_MAX_ON_SPR 2
+#define CHAN_RANK_MAX_ON_EMR 8
+#define DIMM_IDX_MAX_ON_EMR 2
#define CHAN_RANK_MAX CHAN_RANK_MAX_ON_HSX
#define DIMM_IDX_MAX DIMM_IDX_MAX_ON_HSX
@@ -571,6 +573,12 @@ read_thresholds_spr(struct peci_dimmtemp *priv, int dimm_order, int chan_rank, u
return 0;
}
+static int read_thresholds_emr(struct peci_dimmtemp *priv, int dimm_order,
+ int chan_rank, u32 *data)
+{
+ return read_thresholds_spr(priv, dimm_order, chan_rank, data);
+}
+
static const struct dimm_info dimm_hsx = {
.chan_rank_max = CHAN_RANK_MAX_ON_HSX,
.dimm_idx_max = DIMM_IDX_MAX_ON_HSX,
@@ -620,6 +628,13 @@ static const struct dimm_info dimm_spr = {
.read_thresholds = &read_thresholds_spr,
};
+static const struct dimm_info dimm_emr = {
+ .chan_rank_max = CHAN_RANK_MAX_ON_EMR,
+ .dimm_idx_max = DIMM_IDX_MAX_ON_EMR,
+ .min_peci_revision = 0x40,
+ .read_thresholds = &read_thresholds_emr,
+};
+
static const struct auxiliary_device_id peci_dimmtemp_ids[] = {
{
.name = "peci_cpu.dimmtemp.hsx",
@@ -649,6 +664,10 @@ static const struct auxiliary_device_id peci_dimmtemp_ids[] = {
.name = "peci_cpu.dimmtemp.spr",
.driver_data = (kernel_ulong_t)&dimm_spr,
},
+ {
+ .name = "peci_cpu.dimmtemp.emr",
+ .driver_data = (kernel_ulong_t)&dimm_emr,
+ },
{ }
};
MODULE_DEVICE_TABLE(auxiliary, peci_dimmtemp_ids);

Reviewed-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>


Kind regards,

Paul