[PATCH 4/7] platform/x86/intel/bff: Add Diamond Rapids support
From: Tony Luck
Date: Tue Aug 25 2026 - 14:16:54 EST
There are potentially bitfix filters associated with each machine check
bank. Only some banks may implement them.
Machine check banks have varying scope. E.g. there is a separate L2
cache for each module, each instance has its own bitfix filter.
Add information that will be used to map a <cpu,bank> pair to a unique
instance number for a bitfix filter.
Co-developed-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
---
drivers/platform/x86/intel/bff.c | 41 ++++++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
diff --git a/drivers/platform/x86/intel/bff.c b/drivers/platform/x86/intel/bff.c
index 9522bdb1401d..6360bbc92347 100644
--- a/drivers/platform/x86/intel/bff.c
+++ b/drivers/platform/x86/intel/bff.c
@@ -18,18 +18,51 @@
#define pr_fmt(fmt) "bff: " fmt
#include <linux/cpufeature.h>
+#include <linux/device-id/x86_cpu.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/printk.h>
#include <linux/types.h>
+#include <asm/cpu_device_id.h>
#include <asm/cpufeatures.h>
+#include <asm/intel-family.h>
#include <asm/mce.h>
#include <asm/msr.h>
#include <asm/msr-index.h>
+/* Machine check bank scope types */
+enum bff_type {
+ BFF_NONE = 0,
+ BFF_BANK_DCU,
+ BFF_BANK_DTLB,
+ BFF_BANK_MLC,
+ BFF_BANK_CCF,
+ BFF_BANK_HSF,
+ BFF_BANK_IOCACHE,
+};
+
+static const enum bff_type dmr_mcbanks[MAX_NR_BANKS] = {
+ [1] = BFF_BANK_DCU,
+ [2] = BFF_BANK_DTLB,
+ [3] = BFF_BANK_MLC,
+ [6] = BFF_BANK_CCF,
+ [13] = BFF_BANK_HSF,
+ [17] = BFF_BANK_IOCACHE
+};
+
+static const struct x86_cpu_id bff_cpu_ids[] __initconst = {
+ X86_MATCH_VFM(INTEL_DIAMONDRAPIDS_X, dmr_mcbanks),
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, bff_cpu_ids);
+
+static const enum bff_type *bank_types;
+
static int __init bff_init(void)
{
+ const struct x86_cpu_id *m;
u64 core_caps, mcg_cap;
if (!cpu_feature_enabled(X86_FEATURE_MCA))
@@ -45,6 +78,14 @@ static int __init bff_init(void)
if (!(core_caps & MSR_IA32_CORE_CAPS_BFF_RESET_DETECT))
return -ENODEV;
+ m = x86_match_cpu(bff_cpu_ids);
+ if (!m) {
+ pr_info("CPU supports bitfix filter, but driver does not\n");
+ return -ENODEV;
+ }
+
+ bank_types = (const enum bff_type *)m->driver_data;
+
return 0;
}
--
2.55.0