[PATCH v9 3/8] PCI: Add defines for TLP Header/Prefix log sizes

Ilpo Järvinen
2025-01-14T17:09:17Z

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.

Suggested-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
drivers/pci/pcie/dpc.c | 10 ++++++----
drivers/pci/pcie/tlp.c | 2 +-
drivers/pci/quirks.c | 6 ++++--
include/linux/aer.h | 9 ++++++++-
4 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 2b6ef7efa3c1..0674d8c89bfa 100644
--- 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 3f053cc62290..4cc76bd1867a 100644
--- 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 76f4df75b08a..84487615e1d1 100644
--- 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 190a0a2061cd..4ef6515c3205 100644
--- 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 {
--
2.39.5