linux-kernel - [PATCH v3 1/2] EDAC/amd64: Set memory type per DIMM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 28 Dec 2021 20:06:14 +0000
From:   Yazen Ghannam <yazen.ghannam@....com>
To:     <linux-edac@...r.kernel.org>
CC:     <linux-kernel@...r.kernel.org>, <bp@...en8.de>,
        <mchehab@...nel.org>, <tony.luck@...el.com>, <james.morse@....com>,
        <rric@...nel.org>, <Smita.KoralahalliChannabasappa@....com>,
        <william.roche@...cle.com>, "Yazen Ghannam" <yazen.ghannam@....com>
Subject: [PATCH v3 1/2] EDAC/amd64: Set memory type per DIMM

Current AMD systems allow mixing of DIMM types within a system. However,
DIMMs within a channel, i.e. managed by a single Unified Memory
Controller (UMC), must be of the same type.

Handle this possible configuration by checking and setting the memory
type for each individual EDAC "DIMM" structure.

Signed-off-by: Yazen Ghannam <yazen.ghannam@....com>
---
Link:
https://lkml.kernel.org/r/20211215155309.2711917-2-yazen.ghannam@amd.com

v2->v3:
* Change patch to properly handle systems with different DIMM types.

v1->v2:
* Was patch 3 in v1.
* Update commit message.

 drivers/edac/amd64_edac.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index fba609ada0e6..4db92c77276f 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -1616,19 +1616,23 @@ static void read_dct_base_mask(struct amd64_pvt *pvt)
 	}
 }
 
+static enum mem_type determine_memory_type_df(struct amd64_umc *umc)
+{
+	if (umc->dimm_cfg & BIT(5))
+		return MEM_LRDDR4;
+
+	if (umc->dimm_cfg & BIT(4))
+		return MEM_RDDR4;
+
+	return MEM_DDR4;
+}
+
 static void determine_memory_type(struct amd64_pvt *pvt)
 {
 	u32 dram_ctrl, dcsm;
 
-	if (pvt->umc) {
-		if ((pvt->umc[0].dimm_cfg | pvt->umc[1].dimm_cfg) & BIT(5))
-			pvt->dram_type = MEM_LRDDR4;
-		else if ((pvt->umc[0].dimm_cfg | pvt->umc[1].dimm_cfg) & BIT(4))
-			pvt->dram_type = MEM_RDDR4;
-		else
-			pvt->dram_type = MEM_DDR4;
+	if (pvt->umc)
 		return;
-	}
 
 	switch (pvt->fam) {
 	case 0xf:
@@ -3547,8 +3551,8 @@ static int init_csrows_df(struct mem_ctl_info *mci)
 			edac_dbg(1, "MC node: %d, csrow: %d\n",
 					pvt->mc_node_id, cs);
 
+			dimm->mtype = determine_memory_type_df(&pvt->umc[umc]);
 			dimm->nr_pages = get_csrow_nr_pages(pvt, umc, cs);
-			dimm->mtype = pvt->dram_type;
 			dimm->edac_mode = edac_mode;
 			dimm->dtype = dev_type;
 			dimm->grain = 64;
-- 
2.25.1