[PATCH v4 19/23] cxl/pci: Update CXL error logging to use RAS register address

From: Terry Bowman
Date: Tue May 23 2023 - 19:27:39 EST


The CXL error handler currently only logs endpoint RAS status. The CXL
topology includes several components providing RAS details to be logged
during error handling.[1] Update the current handler's RAS logging to use a
RAS register address. This will allow for adding support to log other CXL
component's RAS details in the future.

[1] CXL3.0 Table 8-22 CXL_Capability_ID Assignment

Co-developed-by: Robert Richter <rrichter@xxxxxxx>
Signed-off-by: Robert Richter <rrichter@xxxxxxx>
Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>
---
drivers/cxl/core/pci.c | 42 ++++++++++++++++++++++++++++++------------
1 file changed, 30 insertions(+), 12 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 67f4ab6daa34..def6ee5ab4f5 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -665,32 +665,36 @@ void read_cdat_data(struct cxl_port *port)
}
EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL);

-void cxl_cor_error_detected(struct pci_dev *pdev)
+static void __cxl_log_correctable_ras(struct cxl_dev_state *cxlds,
+ void __iomem *ras_base)
{
- struct cxl_dev_state *cxlds = pci_get_drvdata(pdev);
void __iomem *addr;
u32 status;

- if (!cxlds->regs.ras)
+ if (!ras_base)
return;

- addr = cxlds->regs.ras + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
+ 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);
trace_cxl_aer_correctable_error(cxlds->cxlmd, status);
}
}
-EXPORT_SYMBOL_NS_GPL(cxl_cor_error_detected, CXL);
+
+static void cxl_log_correctable_ras_endpoint(struct cxl_dev_state *cxlds)
+{
+ return __cxl_log_correctable_ras(cxlds, cxlds->regs.ras);
+}

/* CXL spec rev3.0 8.2.4.16.1 */
-static void header_log_copy(struct cxl_dev_state *cxlds, u32 *log)
+static void header_log_copy(void __iomem *ras_base, u32 *log)
{
void __iomem *addr;
u32 *log_addr;
int i, log_u32_size = CXL_HEADERLOG_SIZE / sizeof(u32);

- addr = cxlds->regs.ras + CXL_RAS_HEADER_LOG_OFFSET;
+ addr = ras_base + CXL_RAS_HEADER_LOG_OFFSET;
log_addr = log;

for (i = 0; i < log_u32_size; i++) {
@@ -704,17 +708,18 @@ static void header_log_copy(struct cxl_dev_state *cxlds, u32 *log)
* Log the state of the RAS status registers and prepare them to log the
* next error status. Return 1 if reset needed.
*/
-static bool cxl_report_and_clear(struct cxl_dev_state *cxlds)
+static bool __cxl_report_and_clear(struct cxl_dev_state *cxlds,
+ void __iomem *ras_base)
{
u32 hl[CXL_HEADERLOG_SIZE_U32];
void __iomem *addr;
u32 status;
u32 fe;

- if (!cxlds->regs.ras)
+ if (!ras_base)
return false;

- addr = cxlds->regs.ras + CXL_RAS_UNCORRECTABLE_STATUS_OFFSET;
+ addr = ras_base + CXL_RAS_UNCORRECTABLE_STATUS_OFFSET;
status = readl(addr);
if (!(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK))
return false;
@@ -722,7 +727,7 @@ static bool cxl_report_and_clear(struct cxl_dev_state *cxlds)
/* If multiple errors, log header points to first error from ctrl reg */
if (hweight32(status) > 1) {
void __iomem *rcc_addr =
- cxlds->regs.ras + CXL_RAS_CAP_CONTROL_OFFSET;
+ ras_base + CXL_RAS_CAP_CONTROL_OFFSET;

fe = BIT(FIELD_GET(CXL_RAS_CAP_CONTROL_FE_MASK,
readl(rcc_addr)));
@@ -730,13 +735,26 @@ static bool cxl_report_and_clear(struct cxl_dev_state *cxlds)
fe = status;
}

- header_log_copy(cxlds, hl);
+ header_log_copy(ras_base, hl);
trace_cxl_aer_uncorrectable_error(cxlds->cxlmd, status, fe, hl);
writel(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK, addr);

return true;
}

+static bool cxl_report_and_clear(struct cxl_dev_state *cxlds)
+{
+ return __cxl_report_and_clear(cxlds, cxlds->regs.ras);
+}
+
+void cxl_cor_error_detected(struct pci_dev *pdev)
+{
+ struct cxl_dev_state *cxlds = pci_get_drvdata(pdev);
+
+ cxl_log_correctable_ras_endpoint(cxlds);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_cor_error_detected, CXL);
+
pci_ers_result_t cxl_error_detected(struct pci_dev *pdev,
pci_channel_state_t state)
{
--
2.34.1