[PATCH v7 10/17] cxl/pci: Add log message and add type check in existing RAS handlers

Terry Bowman
2025-02-11T19:26:45Z

The CXL RAS handlers do not currently log if the RAS registers are
unmapped. This is needed in order to help debug CXL error handling. Update
the CXL driver to log a warning message if the RAS register block is
unmapped.

Also, add type check before processing EP or RCH DP.

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Gregory Price <gourry@gourry.net>
---
drivers/cxl/core/pci.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 69bb030aa8e1..af809e7cbe3b 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -658,15 +658,19 @@ static void __cxl_handle_cor_ras(struct device *dev,
void __iomem *addr;
u32 status;

- if (!ras_base)
+ if (!ras_base) {
+ dev_warn_once(dev, "CXL RAS register block is not mapped");
return;
+ }

addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
status = readl(addr);
- if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
- writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
+ if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
+ return;
+ writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
+
+ if (is_cxl_memdev(dev))
trace_cxl_aer_correctable_error(to_cxl_memdev(dev), status);
- }
}

static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)
@@ -702,8 +706,10 @@ static bool __cxl_handle_ras(struct device *dev, void __iomem *ras_base)
u32 status;
u32 fe;

- if (!ras_base)
+ if (!ras_base) {
+ dev_warn_once(dev, "CXL RAS register block is not mapped");
return false;
+ }

addr = ras_base + CXL_RAS_UNCORRECTABLE_STATUS_OFFSET;
status = readl(addr);
@@ -722,7 +728,9 @@ static bool __cxl_handle_ras(struct device *dev, void __iomem *ras_base)
}

header_log_copy(ras_base, hl);
- trace_cxl_aer_uncorrectable_error(to_cxl_memdev(dev), status, fe, hl);
+ if (is_cxl_memdev(dev))
+ trace_cxl_aer_uncorrectable_error(to_cxl_memdev(dev), status, fe, hl);
+
writel(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK, addr);

return true;
--
2.34.1