From: ppwaskie@kernel.org
To: Dan Williams <dan.j.williams@intel.com>,
linux-cxl@vger.kernel.org, linux-pci@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, PJ Waskiewicz <ppwaskie@kernel.org>
Subject: [PATCH 1/1] cxl/acpi.c: Add buggy BIOS hint for CXL ACPI lookup failure
Date: Sun, 7 Apr 2024 14:05:26 -0700 [thread overview]
Message-ID: <20240407210526.8500-1-ppwaskie@kernel.org> (raw)
From: PJ Waskiewicz <ppwaskie@kernel.org>
Currently, Type 3 CXL devices (CXL.mem) can train using host CXL
drivers on Emerald Rapids systems. However, on some production
systems from some vendors, a buggy BIOS exists that improperly
populates the ACPI => PCI mappings. This leads to the cxl_acpi
driver to fail probe when it cannot find the root port's _UID, in
order to look up the device's CXL attributes in the CEDT.
Add a bit more of a descriptive message that the lookup failure
could be a bad BIOS, rather than just "failed."
Signed-off-by: PJ Waskiewicz <ppwaskie@kernel.org>
---
drivers/cxl/acpi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index af5cb818f84d..56019466a09c 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -504,7 +504,7 @@ static int cxl_get_chbs(struct device *dev, struct acpi_device *hb,
rc = acpi_evaluate_integer(hb->handle, METHOD_NAME__UID, NULL, &uid);
if (rc != AE_OK) {
- dev_err(dev, "unable to retrieve _UID\n");
+ dev_err(dev, "unable to retrieve _UID. Potentially buggy BIOS\n");
return -ENOENT;
}
--
2.40.1
next reply other threads:[~2024-04-07 21:05 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-07 21:05 ppwaskie [this message]
2024-04-07 21:28 ` [PATCH 1/1] cxl/acpi.c: Add buggy BIOS hint for CXL ACPI lookup failure Lukas Wunner
2024-04-08 2:03 ` PJ Waskiewicz
2024-04-08 8:34 ` Jonathan Cameron
2024-04-08 19:29 ` PJ Waskiewicz
2024-04-08 20:45 ` Dan Williams
2024-04-08 21:32 ` PJ Waskiewicz
2024-04-09 4:22 ` PJ Waskiewicz
2024-04-08 16:54 ` Dan Williams
2024-04-08 19:25 ` PJ Waskiewicz
2024-04-09 13:22 ` Bjorn Helgaas
2024-04-29 5:57 ` PJ Waskiewicz
2024-04-29 15:31 ` Bjorn Helgaas
2024-04-29 18:35 ` Dan Williams
2024-05-01 15:28 ` PJ Waskiewicz
2024-05-01 15:47 ` Dan Williams
2024-05-02 17:34 ` PJ Waskiewicz
2024-05-02 18:29 ` Dan Williams
2024-05-01 17:54 ` Bjorn Helgaas
2024-05-02 17:30 ` PJ Waskiewicz
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