EINJ, CXL: Fix CXL device SBDF calculation
PATCH RESEND 1/1 EINJ, CXL: Fix CXL device SBDF calculation
The SBDF of the target CXL 2.0 compliant root port is required to inject a CXL protocol error as per ACPI 6.5. The SBDF given has to be in the following format:
31 24 23 16 15 11 10 8 7 0
+-------------------------------------------------+ | segment | bus | device | function | reserved | +-------------------------------------------------+
The SBDF calculated in cxl_dport_get_sbdf() doesn't account for the reserved bits currently, causing the wrong SBDF to be used. Fix said calculation to properly shift the SBDF.
Without this fix, error injection into CXL 2.0 root ports through the CXL debugfs interface (<debugfs>/cxl) is broken. Injection through the legacy interface (<debugfs>/apei/einj/) will still work because the SBDF is manually provided by the user.
---
Resent to add linux-cxl list and Srinivasulu to CC
--- drivers/acpi/apei/einj-cxl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/acpi/apei/einj-cxl.c +1 -1
@@ -63,7 +63,7 @@ static int cxl_dport_get_sbdf(struct pci_dev *dport_dev, u64 *sbdf) seg = bridge->domain_nr; bus = pbus->number; - *sbdf = (seg <<24 ) | (bus <<16 ) | dport_dev->devfn; + *sbdf = (seg <<24 ) | (bus <<16 ) | (dport_dev->devfn <<8 );return 0 ; }
Signature · 1 line
2.34.1
Quoted 13 lines · Ben Cheatham
The SBDF of the target CXL 2.0 compliant root port is required to inject a CXL protocol error as per ACPI 6.5. The SBDF given has to be in the following format:
31 24 23 16 15 11 10 8 7 0
+-------------------------------------------------+ | segment | bus | device | function | reserved | +-------------------------------------------------+The SBDF calculated in
cxl_dport_get_sbdf()doesn't account for the reserved bits currently, causing the wrong SBDF to be used. Fix said calculation to properly shift the SBDF.
Quoted 7 lines
Without this fix, error injection into CXL 2.0 root ports through the CXL debugfs interface (<debugfs>/cxl) is broken. Injection through the legacy interface (<debugfs>/apei/einj/) will still work because the SBDF is manually provided by the user.
Fixes 12fb28ea6b1cf ("EINJ: Add CXL error type support")Signed-off-by Ben Cheatham <[email protected]>
Looks good to me.
Micron Confidential
Micron Confidential
Quoted 27 lines
-----Original Message-----
From: Ben Cheatham <[email protected]>
Sent: Friday, September 27, 2024 10:04 PM
To: [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Cc: [email protected]; [email protected]; [email protected]; [email protected]; Srinivasulu Thanneeru <[email protected]>; Ben Cheatham <[email protected]>
Subject: [EXT] [RESEND][PATCH] EINJ, CXL: Fix CXL device SBDF calculationCAUTION: EXTERNAL EMAIL. Do not click links or open attachments unless you recognize the sender and were expecting this message.
The SBDF of the target CXL 2.0 compliant root port is required to inject a CXL protocol error as per ACPI 6.5. The SBDF given has to be in the following format:
31 24 23 16 15 11 10 8 7 0
+-------------------------------------------------+ | segment | bus | device | function | reserved | +-------------------------------------------------+The SBDF calculated in
cxl_dport_get_sbdf()doesn't account for the reserved bits currently, causing the wrong SBDF to be used. Fix said calculation to properly shift the SBDF.
Quoted 7 lines
Without this fix, error injection into CXL 2.0 root ports through the CXL debugfs interface (<debugfs>/cxl) is broken. Injection through the legacy interface (<debugfs>/apei/einj/) will still work because the SBDF is manually provided by the user.
Fixes 12fb28ea6b1cf ("EINJ: Add CXL error type support")Signed-off-by Ben Cheatham <[email protected]>
Tried this patch, working fine.
Quoted 25 lines
---
Resent to add linux-cxl list and Srinivasulu to CC
---
drivers/acpi/apei/einj-cxl.c| 2 +-1 file changed, 1 insertion(+), 1 deletion(-)drivers/acpi/apei/einj-cxl.c +1
-1@@ -63,7 +63,7 @@ static int cxl_dport_get_sbdf(struct pci_dev *dport_dev, u64 *sbdf) seg = bridge->domain_nr; bus = pbus->number; - *sbdf = (seg <<24 ) | (bus <<16 ) | dport_dev->devfn; + *sbdf = (seg <<24 ) | (bus <<16 ) | (dport_dev->devfn <<8 );return 0 ;}
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2.34.1