PCI: Add defines for TLP Header/Prefix log sizes

Add defines for AER and DPC capabilities TLP Header Logging register sizes
(PCIe r6.2, sec 7.8.4 / 7.9.14) and replace literals with them.

Link: https://lore.kernel.org/r/20250114170840.1633-4-ilpo.jarvinen@linux.intel.com
Suggested-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 2b6ef7efa3c113ad0c4b982dc922c7d661c7fffa..0674d8c89bfa943c4bfc6ef1e3ec46984858d4fc 100644 (file)
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -215,18 +215,18 @@ static void dpc_process_rp_pio_error(struct pci_dev *pdev)
                                first_error == i ? " (First)" : "");
        }
 
-       if (pdev->dpc_rp_log_size < 4)
+       if (pdev->dpc_rp_log_size < PCIE_STD_NUM_TLP_HEADERLOG)
                goto clear_status;
        pcie_read_tlp_log(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG, &tlp_log);
        pci_err(pdev, "TLP Header: %#010x %#010x %#010x %#010x\n",
                tlp_log.dw[0], tlp_log.dw[1], tlp_log.dw[2], tlp_log.dw[3]);
 
-       if (pdev->dpc_rp_log_size < 5)
+       if (pdev->dpc_rp_log_size < PCIE_STD_NUM_TLP_HEADERLOG + 1)
                goto clear_status;
        pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG, &log);
        pci_err(pdev, "RP PIO ImpSpec Log %#010x\n", log);
 
-       for (i = 0; i < pdev->dpc_rp_log_size - 5; i++) {
+       for (i = 0; i < pdev->dpc_rp_log_size - PCIE_STD_NUM_TLP_HEADERLOG - 1; i++) {
                pci_read_config_dword(pdev,
                        cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG + i * 4, &prefix);
                pci_err(pdev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix);
@@ -404,7 +404,9 @@ void pci_dpc_init(struct pci_dev *pdev)
        if (!pdev->dpc_rp_log_size) {
                pdev->dpc_rp_log_size =
                                FIELD_GET(PCI_EXP_DPC_RP_PIO_LOG_SIZE, cap);
-               if (pdev->dpc_rp_log_size < 4 || pdev->dpc_rp_log_size > 9) {
+               if (pdev->dpc_rp_log_size < PCIE_STD_NUM_TLP_HEADERLOG ||
+                   pdev->dpc_rp_log_size > PCIE_STD_NUM_TLP_HEADERLOG + 1 +
+                                           PCIE_STD_MAX_TLP_PREFIXLOG) {
                        pci_err(pdev, "RP PIO log size %u is invalid\n",
                                pdev->dpc_rp_log_size);
                        pdev->dpc_rp_log_size = 0;

diff --git a/drivers/pci/pcie/tlp.c b/drivers/pci/pcie/tlp.c
index 3f053cc62290031de8ccd87628d4d37eb0acae44..4cc76bd1867a499989b3b2220d2227667d601836 100644 (file)
--- a/drivers/pci/pcie/tlp.c
+++ b/drivers/pci/pcie/tlp.c
@@ -28,7 +28,7 @@ int pcie_read_tlp_log(struct pci_dev *dev, int where,
 
        memset(tlp_log, 0, sizeof(*tlp_log));
 
-       for (i = 0; i < 4; i++) {
+       for (i = 0; i < PCIE_STD_NUM_TLP_HEADERLOG; i++) {
                ret = pci_read_config_dword(dev, where + i * 4,
                                            &tlp_log->dw[i]);
                if (ret)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 76f4df75b08a148103a3d5683e189f4677c02282..84487615e1d1946c37bb25b3466c9bf8308441b2 100644 (file)
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -12,6 +12,7 @@
  * file, where their drivers can use them.
  */
 
+#include <linux/aer.h>
 #include <linux/align.h>
 #include <linux/bitfield.h>
 #include <linux/types.h>
@@ -6233,8 +6234,9 @@ static void dpc_log_size(struct pci_dev *dev)
                return;
 
        if (FIELD_GET(PCI_EXP_DPC_RP_PIO_LOG_SIZE, val) == 0) {
-               pci_info(dev, "Overriding RP PIO Log Size to 4\n");
-               dev->dpc_rp_log_size = 4;
+               pci_info(dev, "Overriding RP PIO Log Size to %d\n",
+                        PCIE_STD_NUM_TLP_HEADERLOG);
+               dev->dpc_rp_log_size = PCIE_STD_NUM_TLP_HEADERLOG;
        }
 }
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x461f, dpc_log_size);

diff --git a/include/linux/aer.h b/include/linux/aer.h
index 190a0a2061cda86184e2bcf7261cbb8659a8c420..4ef6515c320598fef90200503fd68e54f60ae1a5 100644 (file)
--- a/include/linux/aer.h
+++ b/include/linux/aer.h
@@ -16,10 +16,17 @@
 #define AER_CORRECTABLE                        2
 #define DPC_FATAL                      3
 
+/*
+ * AER and DPC capabilities TLP Logging register sizes (PCIe r6.2, sec 7.8.4
+ * & 7.9.14).
+ */
+#define PCIE_STD_NUM_TLP_HEADERLOG     4
+#define PCIE_STD_MAX_TLP_PREFIXLOG     4
+
 struct pci_dev;
 
 struct pcie_tlp_log {
-       u32 dw[4];
+       u32 dw[PCIE_STD_NUM_TLP_HEADERLOG];
 };
 
 struct aer_capability_regs {