Merge branch 'pci/err'

bjorn-helgaas · bjorn-helgaas · commit f4a09274c592 · 2025-01-23T13:04:50.000-06:00
- Unexport pcie_read_tlp_log() to encourage drivers to use PCI core logging
  rather than building their own (Ilpo Järvinen)

- Move TLP Log handling to its own file (Ilpo Järvinen)

- Add #defines for TLP Header/Prefix log sizes (Ilpo Järvinen)

- Store number of supported End-End TLP Prefixes always so we can read the
  correct number of DWORDs from the TLP Prefix Log (Ilpo Järvinen)

- Read TLP Prefixes in addition to the Header Log in pcie_read_tlp_log()
  (Ilpo Järvinen)

- Add pcie_print_tlp_log() to consolidate printing of TLP Header and Prefix
  Log (Ilpo Järvinen)

* pci/err:
  PCI: Add pcie_print_tlp_log() to print TLP Header and Prefix Log
  PCI: Add TLP Prefix reading to pcie_read_tlp_log()
  PCI: Store number of supported End-End TLP Prefixes
  PCI: Use unsigned int i in pcie_read_tlp_log()
  PCI: Use same names in pcie_read_tlp_log() prototype and definition
  PCI: Add defines for TLP Header/Prefix log sizes
  PCI: Move TLP Log handling to its own file
  PCI: Don't expose pcie_read_tlp_log() outside PCI subsystem
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
@@ -410,7 +410,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
 	if (WARN_ON(pdev->pasid_enabled))
 		return -EBUSY;
 
-	if (!pdev->eetlp_prefix_path && !pdev->pasid_no_tlp)
+	if (!pdev->eetlp_prefix_max && !pdev->pasid_no_tlp)
 		return -EINVAL;
 
 	if (!pasid)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
@@ -1099,34 +1099,6 @@ static void pci_enable_acs(struct pci_dev *dev)
 	pci_write_config_word(dev, pos + PCI_ACS_CTRL, caps.ctrl);
 }
 
-/**
- * pcie_read_tlp_log - read TLP Header Log
- * @dev: PCIe device
- * @where: PCI Config offset of TLP Header Log
- * @tlp_log: TLP Log structure to fill
- *
- * Fill @tlp_log from TLP Header Log registers, e.g., AER or DPC.
- *
- * Return: 0 on success and filled TLP Log structure, <0 on error.
- */
-int pcie_read_tlp_log(struct pci_dev *dev, int where,
-		      struct pcie_tlp_log *tlp_log)
-{
-	int i, ret;
-
-	memset(tlp_log, 0, sizeof(*tlp_log));
-
-	for (i = 0; i < 4; i++) {
-		ret = pci_read_config_dword(dev, where + i * 4,
-					    &tlp_log->dw[i]);
-		if (ret)
-			return pcibios_err_to_errno(ret);
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(pcie_read_tlp_log);
-
 /**
  * pci_restore_bars - restore a device's BAR values (e.g. after wake-up)
  * @dev: PCI device to have its BARs restored
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
@@ -4,6 +4,8 @@
 
 #include <linux/pci.h>
 
+struct pcie_tlp_log;
+
 /* Number of possible devfns: 0.0 to 1f.7 inclusive */
 #define MAX_NR_DEVFNS 256
 
@@ -549,6 +551,12 @@ struct aer_err_info {
 
 int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info);
 void aer_print_error(struct pci_dev *dev, struct aer_err_info *info);
+
+int pcie_read_tlp_log(struct pci_dev *dev, int where, int where2,
+		      unsigned int tlp_len, struct pcie_tlp_log *log);
+unsigned int aer_tlp_log_len(struct pci_dev *dev, u32 aercc);
+void pcie_print_tlp_log(const struct pci_dev *dev,
+			const struct pcie_tlp_log *log, const char *pfx);
 #endif	/* CONFIG_PCIEAER */
 
 #ifdef CONFIG_PCIEPORTBUS
@@ -567,6 +575,7 @@ void pci_dpc_init(struct pci_dev *pdev);
 void dpc_process_error(struct pci_dev *pdev);
 pci_ers_result_t dpc_reset_link(struct pci_dev *pdev);
 bool pci_dpc_recovered(struct pci_dev *pdev);
+unsigned int dpc_tlp_log_len(struct pci_dev *dev);
 #else
 static inline void pci_save_dpc_state(struct pci_dev *dev) { }
 static inline void pci_restore_dpc_state(struct pci_dev *dev) { }
diff --git a/drivers/pci/pcie/Makefile b/drivers/pci/pcie/Makefile
@@ -7,7 +7,7 @@ pcieportdrv-y			:= portdrv.o rcec.o
 obj-$(CONFIG_PCIEPORTBUS)	+= pcieportdrv.o bwctrl.o
 
 obj-y				+= aspm.o
-obj-$(CONFIG_PCIEAER)		+= aer.o err.o
+obj-$(CONFIG_PCIEAER)		+= aer.o err.o tlp.o
 obj-$(CONFIG_PCIEAER_INJECT)	+= aer_inject.o
 obj-$(CONFIG_PCIE_PME)		+= pme.o
 obj-$(CONFIG_PCIE_DPC)		+= dpc.o
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
@@ -665,12 +665,6 @@ static void pci_rootport_aer_stats_incr(struct pci_dev *pdev,
 	}
 }
 
-static void __print_tlp_header(struct pci_dev *dev, struct pcie_tlp_log *t)
-{
-	pci_err(dev, "  TLP Header: %08x %08x %08x %08x\n",
-		t->dw[0], t->dw[1], t->dw[2], t->dw[3]);
-}
-
 static void __aer_print_error(struct pci_dev *dev,
 			      struct aer_err_info *info)
 {
@@ -725,7 +719,7 @@ void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
 	__aer_print_error(dev, info);
 
 	if (info->tlp_header_valid)
-		__print_tlp_header(dev, &info->tlp);
+		pcie_print_tlp_log(dev, &info->tlp, dev_fmt("  "));
 
 out:
 	if (info->id && info->error_dev_num > 1 && info->id == id)
@@ -797,7 +791,7 @@ void pci_print_aer(struct pci_dev *dev, int aer_severity,
 			aer->uncor_severity);
 
 	if (tlp_header_valid)
-		__print_tlp_header(dev, &aer->header_log);
+		pcie_print_tlp_log(dev, &aer->header_log, dev_fmt("  "));
 
 	trace_aer_event(dev_name(&dev->dev), (status & ~mask),
 			aer_severity, tlp_header_valid, &aer->header_log);
@@ -1248,7 +1242,10 @@ int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
 
 		if (info->status & AER_LOG_TLP_MASKS) {
 			info->tlp_header_valid = 1;
-			pcie_read_tlp_log(dev, aer + PCI_ERR_HEADER_LOG, &info->tlp);
+			pcie_read_tlp_log(dev, aer + PCI_ERR_HEADER_LOG,
+					  aer + PCI_ERR_PREFIX_LOG,
+					  aer_tlp_log_len(dev, aercc),
+					  &info->tlp);
 		}
 	}
 
diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
@@ -190,7 +190,7 @@ pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
 static void dpc_process_rp_pio_error(struct pci_dev *pdev)
 {
 	u16 cap = pdev->dpc_cap, dpc_status, first_error;
-	u32 status, mask, sev, syserr, exc, log, prefix;
+	u32 status, mask, sev, syserr, exc, log;
 	struct pcie_tlp_log tlp_log;
 	int i;
 
@@ -215,22 +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]);
+	pcie_read_tlp_log(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG,
+			  cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG,
+			  dpc_tlp_log_len(pdev), &tlp_log);
+	pcie_print_tlp_log(pdev, &tlp_log, dev_fmt(""));
 
-	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++) {
-		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);
-	}
  clear_status:
 	pci_write_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, status);
 }
@@ -404,7 +400,9 @@ 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
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe TLP Log handling
+ *
+ * Copyright (C) 2024 Intel Corporation
+ */
+
+#include <linux/aer.h>
+#include <linux/array_size.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+
+#include "../pci.h"
+
+/**
+ * aer_tlp_log_len - Calculate AER Capability TLP Header/Prefix Log length
+ * @dev: PCIe device
+ * @aercc: AER Capabilities and Control register value
+ *
+ * Return: TLP Header/Prefix Log length
+ */
+unsigned int aer_tlp_log_len(struct pci_dev *dev, u32 aercc)
+{
+	return PCIE_STD_NUM_TLP_HEADERLOG +
+	       ((aercc & PCI_ERR_CAP_PREFIX_LOG_PRESENT) ?
+		dev->eetlp_prefix_max : 0);
+}
+
+#ifdef CONFIG_PCIE_DPC
+/**
+ * dpc_tlp_log_len - Calculate DPC RP PIO TLP Header/Prefix Log length
+ * @dev: PCIe device
+ *
+ * Return: TLP Header/Prefix Log length
+ */
+unsigned int dpc_tlp_log_len(struct pci_dev *dev)
+{
+	/* Remove ImpSpec Log register from the count */
+	if (dev->dpc_rp_log_size >= PCIE_STD_NUM_TLP_HEADERLOG + 1)
+		return dev->dpc_rp_log_size - 1;
+
+	return dev->dpc_rp_log_size;
+}
+#endif
+
+/**
+ * pcie_read_tlp_log - read TLP Header Log
+ * @dev: PCIe device
+ * @where: PCI Config offset of TLP Header Log
+ * @where2: PCI Config offset of TLP Prefix Log
+ * @tlp_len: TLP Log length (Header Log + TLP Prefix Log in DWORDs)
+ * @log: TLP Log structure to fill
+ *
+ * Fill @log from TLP Header Log registers, e.g., AER or DPC.
+ *
+ * Return: 0 on success and filled TLP Log structure, <0 on error.
+ */
+int pcie_read_tlp_log(struct pci_dev *dev, int where, int where2,
+		      unsigned int tlp_len, struct pcie_tlp_log *log)
+{
+	unsigned int i;
+	int off, ret;
+	u32 *to;
+
+	memset(log, 0, sizeof(*log));
+
+	for (i = 0; i < tlp_len; i++) {
+		if (i < PCIE_STD_NUM_TLP_HEADERLOG) {
+			off = where + i * 4;
+			to = &log->dw[i];
+		} else {
+			off = where2 + (i - PCIE_STD_NUM_TLP_HEADERLOG) * 4;
+			to = &log->prefix[i - PCIE_STD_NUM_TLP_HEADERLOG];
+		}
+
+		ret = pci_read_config_dword(dev, off, to);
+		if (ret)
+			return pcibios_err_to_errno(ret);
+	}
+
+	return 0;
+}
+
+#define EE_PREFIX_STR " E-E Prefixes:"
+
+/**
+ * pcie_print_tlp_log - Print TLP Header / Prefix Log contents
+ * @dev: PCIe device
+ * @log: TLP Log structure
+ * @pfx: String prefix
+ *
+ * Prints TLP Header and Prefix Log information held by @log.
+ */
+void pcie_print_tlp_log(const struct pci_dev *dev,
+			const struct pcie_tlp_log *log, const char *pfx)
+{
+	char buf[11 * (PCIE_STD_NUM_TLP_HEADERLOG + ARRAY_SIZE(log->prefix)) +
+		 sizeof(EE_PREFIX_STR)];
+	unsigned int i;
+	int len;
+
+	len = scnprintf(buf, sizeof(buf), "%#010x %#010x %#010x %#010x",
+			log->dw[0], log->dw[1], log->dw[2], log->dw[3]);
+
+	if (log->prefix[0])
+		len += scnprintf(buf + len, sizeof(buf) - len, EE_PREFIX_STR);
+	for (i = 0; i < ARRAY_SIZE(log->prefix); i++) {
+		if (!log->prefix[i])
+			break;
+		len += scnprintf(buf + len, sizeof(buf) - len,
+				 " %#010x", log->prefix[i]);
+	}
+
+	pci_err(dev, "%sTLP Header: %s\n", pfx, buf);
+}
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
@@ -2294,8 +2294,8 @@ static void pci_configure_relaxed_ordering(struct pci_dev *dev)
 
 static void pci_configure_eetlp_prefix(struct pci_dev *dev)
 {
-#ifdef CONFIG_PCI_PASID
 	struct pci_dev *bridge;
+	unsigned int eetlp_max;
 	int pcie_type;
 	u32 cap;
 
@@ -2307,15 +2307,19 @@ static void pci_configure_eetlp_prefix(struct pci_dev *dev)
 		return;
 
 	pcie_type = pci_pcie_type(dev);
+
+	eetlp_max = FIELD_GET(PCI_EXP_DEVCAP2_EE_PREFIX_MAX, cap);
+	/* 00b means 4 */
+	eetlp_max = eetlp_max ?: 4;
+
 	if (pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
 	    pcie_type == PCI_EXP_TYPE_RC_END)
-		dev->eetlp_prefix_path = 1;
+		dev->eetlp_prefix_max = eetlp_max;
 	else {
 		bridge = pci_upstream_bridge(dev);
-		if (bridge && bridge->eetlp_prefix_path)
-			dev->eetlp_prefix_path = 1;
+		if (bridge && bridge->eetlp_prefix_max)
+			dev->eetlp_prefix_max = eetlp_max;
 	}
-#endif
 }
 
 static void pci_configure_serr(struct pci_dev *dev)
diff --git 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
@@ -16,10 +16,18 @@
 #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];
+	u32 prefix[PCIE_STD_MAX_TLP_PREFIXLOG];
 };
 
 struct aer_capability_regs {
@@ -37,8 +45,6 @@ struct aer_capability_regs {
 	u16 uncor_err_source;
 };
 
-int pcie_read_tlp_log(struct pci_dev *dev, int where, struct pcie_tlp_log *log);
-
 #if defined(CONFIG_PCIEAER)
 int pci_aer_clear_nonfatal_status(struct pci_dev *dev);
 int pcie_aer_is_native(struct pci_dev *dev);
diff --git a/include/linux/pci.h b/include/linux/pci.h
@@ -407,7 +407,7 @@ struct pci_dev {
 					   supported from root to here */
 #endif
 	unsigned int	pasid_no_tlp:1;		/* PASID works without TLP Prefix */
-	unsigned int	eetlp_prefix_path:1;	/* End-to-End TLP Prefix */
+	unsigned int	eetlp_prefix_max:3;	/* Max # of End-End TLP Prefixes, 0=not supported */
 
 	pci_channel_state_t error_state;	/* Current connectivity state */
 	struct device	dev;			/* Generic device interface */
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
