RE: [PATCH v3 00/29] arm_mpam: Add basic mpam driver
From: Shaopeng Tan (Fujitsu) <hidden>
Date: 2025-10-23 08:16:33
Also in:
linux-acpi, lkml
Subsystem:
mpam driver, the rest · Maintainers:
James Morse, Ben Horgan, Linus Torvalds
Hello James,
This series is based on v6.18-rc4, and can be retrieved from: https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/driver/v3 The rest of the driver can be found here: https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/snapshot/v6.18-rc1
This series(mpam/driver/v3) based on v6.18-rc1 and mpam driver(mpam/snapshot/v6.18-rc1) can not run on my machine(The cause is still unknown), But I applied this series and mpam driver on v6.18-rc2, they are run successfully. Tested-by: Shaopeng Tan <redacted> However, I make a few minor fixes as follows: 1)
diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h
index f890d1381af6..dd6041ae7cc9 100644
--- a/drivers/resctrl/mpam_internal.h
+++ b/drivers/resctrl/mpam_internal.h@@ -645,6 +645,13 @@ static inline void mpam_resctrl_teardown_class(struct mpam_class *class) { } #define MPAMF_IIDR_VARIANT GENMASK(19, 16) #define MPAMF_IIDR_PRODUCTID GENMASK(31, 20) +#define MPAMF_IIDR_REVISON_SHIFT 12 +//#define MPAMF_IIDR_REVISION_SHIFT 12 +#define MPAMF_IIDR_IMPLEMENTER_SHIFT 0 +#define MPAMF_IIDR_VARIANT_SHIFT 16 +#define MPAMF_IIDR_PRODUCTID_SHIFT 20
or #define IIDR_REV(x) ((x) << MPAMF_IIDR_REVISON_SHIFT) s/MPAMF_IIDR_REVISON_SHIFT/MPAMF_IIDR_REVISION_SHIFT/ 2)
diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
index 0ea76b7783b6..99b2bbb80a5a 100644
--- a/drivers/resctrl/mpam_resctrl.c
+++ b/drivers/resctrl/mpam_resctrl.c@@ -1113,9 +1118,9 @@ static void mpam_resctrl_pick_counters(void) update_rmid_limits(cache_size); counter_update_class(QOS_L3_OCCUP_EVENT_ID, class); - return; + break; default: - return; + break; } }
3) when building this series(mpam/driver/v3),the `EXPERT` Kconfig option needs to be explicitly enabled. This aligns with Ben's observation in the following patch: https://lore.kernel.org/lkml/146ad8f4-ef6c-48cb-aed8-db619c8258a8@arm.com/ (local) Best regards, Shaopeng TAN