* [PATCH] iommu/amd: Increase timeout waiting for GA log enablement
@ 2022-05-20 10:22 ` Joerg Roedel
0 siblings, 0 replies; 2+ messages in thread
From: Joerg Roedel @ 2022-05-20 10:22 UTC (permalink / raw)
To: Joerg Roedel
Cc: Suravee Suthikulpanit, Will Deacon, iommu, linux-kernel,
Joerg Roedel, D. Ziegfeld, Jörg-Volker Peetz
From: Joerg Roedel <jroedel@suse.de>
On some systems it can take a long time for the hardware to enable the
GA log of the AMD IOMMU. The current wait time is only 0.1ms, but
testing showed that it can take up to 14ms for the GA log to enter
running state after it has been enabled.
Sometimes the long delay happens when booting the system, sometimes
only on resume. Adjust the timeout accordingly to not print a warning
when hardware takes a longer than usual.
There has already been an attempt to fix this with commit
9b45a7738eec ("iommu/amd: Fix loop timeout issue in iommu_ga_log_enable()")
But that commit was based on some wrong math and did not fix the issue
in all cases.
Cc: "D. Ziegfeld" <dzigg@posteo.de>
Cc: Jörg-Volker Peetz <jvpeetz@web.de>
Fixes: 8bda0cfbdc1a ("iommu/amd: Detect and initialize guest vAPIC log")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/amd/init.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index b4a798c7b347..d8060503ba51 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -84,7 +84,7 @@
#define ACPI_DEVFLAG_LINT1 0x80
#define ACPI_DEVFLAG_ATSDIS 0x10000000
-#define LOOP_TIMEOUT 100000
+#define LOOP_TIMEOUT 2000000
/*
* ACPI table definitions
*
--
2.36.1
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [PATCH] iommu/amd: Increase timeout waiting for GA log enablement
@ 2022-05-20 10:22 ` Joerg Roedel
0 siblings, 0 replies; 2+ messages in thread
From: Joerg Roedel @ 2022-05-20 10:22 UTC (permalink / raw)
To: Joerg Roedel
Cc: D. Ziegfeld, linux-kernel, iommu, Joerg Roedel,
Jörg-Volker Peetz, Will Deacon
From: Joerg Roedel <jroedel@suse.de>
On some systems it can take a long time for the hardware to enable the
GA log of the AMD IOMMU. The current wait time is only 0.1ms, but
testing showed that it can take up to 14ms for the GA log to enter
running state after it has been enabled.
Sometimes the long delay happens when booting the system, sometimes
only on resume. Adjust the timeout accordingly to not print a warning
when hardware takes a longer than usual.
There has already been an attempt to fix this with commit
9b45a7738eec ("iommu/amd: Fix loop timeout issue in iommu_ga_log_enable()")
But that commit was based on some wrong math and did not fix the issue
in all cases.
Cc: "D. Ziegfeld" <dzigg@posteo.de>
Cc: Jörg-Volker Peetz <jvpeetz@web.de>
Fixes: 8bda0cfbdc1a ("iommu/amd: Detect and initialize guest vAPIC log")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/amd/init.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index b4a798c7b347..d8060503ba51 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -84,7 +84,7 @@
#define ACPI_DEVFLAG_LINT1 0x80
#define ACPI_DEVFLAG_ATSDIS 0x10000000
-#define LOOP_TIMEOUT 100000
+#define LOOP_TIMEOUT 2000000
/*
* ACPI table definitions
*
--
2.36.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2022-05-20 10:22 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-05-20 10:22 [PATCH] iommu/amd: Increase timeout waiting for GA log enablement Joerg Roedel
2022-05-20 10:22 ` Joerg Roedel
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.