[PATCH] arm_mpam: Fix T241-MPAM-4 workaround

Shanker Donthineni sdonthineni at nvidia.com
Mon Aug 19 15:08:18 PDT 2024


The workaround for T241-MPAM-4 was applied incorrectly, leading to
MBW_MIN being programmed with a zero value when the user specifies
MBW_MAX is less than 5%.

This patch ensures that MBW_MIN is programmed with a non-zero value,
set to 1 to fix the T241-MPAM-4 as expected.

Fixes: 13ff1b527e40 ("arm_mpam: Add workaround for T241-MPAM-4")
Signed-off-by: Shanker Donthineni <sdonthineni at nvidia.com>
---
 drivers/platform/arm64/mpam/mpam_devices.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/arm64/mpam/mpam_devices.c b/drivers/platform/arm64/mpam/mpam_devices.c
index a802ca1c9f05..e49a27c02c66 100644
--- a/drivers/platform/arm64/mpam/mpam_devices.c
+++ b/drivers/platform/arm64/mpam/mpam_devices.c
@@ -2990,7 +2990,7 @@ static void mpam_extend_config(struct mpam_class *class, struct mpam_config *cfg
 	}
 
 	if (mpam_has_quirk(T241_FORCE_MBW_MIN_TO_ONE, class) &&
-	    cfg->mbw_min == 0) {
+	    cfg->mbw_min <= min_hw_granule) {
 		cfg->mbw_min = min_hw_granule + 1;
 		mpam_set_feature(mpam_feat_mbw_min, cfg);
 	}
-- 
2.25.1




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