Browse Source

Merge branch 'pci/dpc' into next

* pci/dpc:
  PCI/DPC: Reformat DPC register definitions
  PCI/DPC: Add and use DPC Status register field definitions
  PCI/DPC: Squash dpc_rp_pio_get_info() into dpc_process_rp_pio_error()
  PCI/DPC: Remove unnecessary RP PIO register structs
  PCI/DPC: Push dpc->rp_pio_status assignment into dpc_rp_pio_get_info()
  PCI/DPC: Squash dpc_rp_pio_print_error() into dpc_rp_pio_get_info()
  PCI/DPC: Make RP PIO log size check more generic
  PCI/DPC: Rename local "status" to "dpc_status"
  PCI/DPC: Squash dpc_rp_pio_print_tlp_header() into dpc_rp_pio_print_error()
  PCI/DPC: Process RP PIO details only if RP PIO extensions supported
  PCI/DPC: Read RP PIO Log Size once at probe
  PCI/DPC: Rename struct dpc_dev.rp to rp_extensions
  PCI/DPC: Add local variable for DPC capability offset
  PCI/DPC: Rename interrupt_event_handler() to dpc_work()
  PCI/DPC: Fix interrupt message number print
  PCI/DPC: Enable DPC only if AER is available
  PCI/DPC: Fix shared interrupt handling
Bjorn Helgaas 7 years ago
parent
commit
3972b0e2c2
4 changed files with 122 additions and 159 deletions
  1. 1 1
      drivers/pci/pcie/Kconfig
  2. 106 145
      drivers/pci/pcie/pcie-dpc.c
  3. 2 2
      drivers/pci/pcie/portdrv_core.c
  4. 13 11
      include/uapi/linux/pci_regs.h

+ 1 - 1
drivers/pci/pcie/Kconfig

@@ -92,7 +92,7 @@ config PCIE_PME
 
 config PCIE_DPC
 	bool "PCIe Downstream Port Containment support"
-	depends on PCIEPORTBUS
+	depends on PCIEPORTBUS && PCIEAER
 	default n
 	help
 	  This enables PCI Express Downstream Port Containment (DPC)

+ 106 - 145
drivers/pci/pcie/pcie-dpc.c

@@ -15,34 +15,15 @@
 #include <linux/pci.h>
 #include <linux/pcieport_if.h>
 #include "../pci.h"
-
-struct rp_pio_header_log_regs {
-	u32 dw0;
-	u32 dw1;
-	u32 dw2;
-	u32 dw3;
-};
-
-struct dpc_rp_pio_regs {
-	u32 status;
-	u32 mask;
-	u32 severity;
-	u32 syserror;
-	u32 exception;
-
-	struct rp_pio_header_log_regs header_log;
-	u32 impspec_log;
-	u32 tlp_prefix_log[4];
-	u32 log_size;
-	u16 first_error;
-};
+#include "aer/aerdrv.h"
 
 struct dpc_dev {
 	struct pcie_device	*dev;
 	struct work_struct	work;
-	int			cap_pos;
-	bool			rp;
+	u16			cap_pos;
+	bool			rp_extensions;
 	u32			rp_pio_status;
+	u8			rp_log_size;
 };
 
 static const char * const rp_pio_error_string[] = {
@@ -72,13 +53,13 @@ static int dpc_wait_rp_inactive(struct dpc_dev *dpc)
 	unsigned long timeout = jiffies + HZ;
 	struct pci_dev *pdev = dpc->dev->port;
 	struct device *dev = &dpc->dev->device;
-	u16 status;
+	u16 cap = dpc->cap_pos, status;
 
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_STATUS, &status);
+	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 	while (status & PCI_EXP_DPC_RP_BUSY &&
 					!time_after(jiffies, timeout)) {
 		msleep(10);
-		pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_STATUS, &status);
+		pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 	}
 	if (status & PCI_EXP_DPC_RP_BUSY) {
 		dev_warn(dev, "DPC root port still busy\n");
@@ -104,11 +85,12 @@ static void dpc_wait_link_inactive(struct dpc_dev *dpc)
 		dev_warn(dev, "Link state not disabled for DPC event\n");
 }
 
-static void interrupt_event_handler(struct work_struct *work)
+static void dpc_work(struct work_struct *work)
 {
 	struct dpc_dev *dpc = container_of(work, struct dpc_dev, work);
 	struct pci_dev *dev, *temp, *pdev = dpc->dev->port;
 	struct pci_bus *parent = pdev->subordinate;
+	u16 cap = dpc->cap_pos, ctl;
 
 	pci_lock_rescan_remove();
 	list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
@@ -124,159 +106,127 @@ static void interrupt_event_handler(struct work_struct *work)
 	pci_unlock_rescan_remove();
 
 	dpc_wait_link_inactive(dpc);
-	if (dpc->rp && dpc_wait_rp_inactive(dpc))
+	if (dpc->rp_extensions && dpc_wait_rp_inactive(dpc))
 		return;
-	if (dpc->rp && dpc->rp_pio_status) {
-		pci_write_config_dword(pdev,
-				      dpc->cap_pos + PCI_EXP_DPC_RP_PIO_STATUS,
-				      dpc->rp_pio_status);
+	if (dpc->rp_extensions && dpc->rp_pio_status) {
+		pci_write_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS,
+				       dpc->rp_pio_status);
 		dpc->rp_pio_status = 0;
 	}
 
-	pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_STATUS,
+	pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,
 		PCI_EXP_DPC_STATUS_TRIGGER | PCI_EXP_DPC_STATUS_INTERRUPT);
-}
 
-static void dpc_rp_pio_print_tlp_header(struct device *dev,
-					struct rp_pio_header_log_regs *t)
-{
-	dev_err(dev, "TLP Header: %#010x %#010x %#010x %#010x\n",
-		t->dw0, t->dw1, t->dw2, t->dw3);
+	pci_read_config_word(pdev, cap + PCI_EXP_DPC_CTL, &ctl);
+	pci_write_config_word(pdev, cap + PCI_EXP_DPC_CTL,
+			      ctl | PCI_EXP_DPC_CTL_INT_EN);
 }
 
-static void dpc_rp_pio_print_error(struct dpc_dev *dpc,
-				   struct dpc_rp_pio_regs *rp_pio)
+static void dpc_process_rp_pio_error(struct dpc_dev *dpc)
 {
 	struct device *dev = &dpc->dev->device;
+	struct pci_dev *pdev = dpc->dev->port;
+	u16 cap = dpc->cap_pos, dpc_status, first_error;
+	u32 status, mask, sev, syserr, exc, dw0, dw1, dw2, dw3, log, prefix;
 	int i;
-	u32 status;
 
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, &status);
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_MASK, &mask);
 	dev_err(dev, "rp_pio_status: %#010x, rp_pio_mask: %#010x\n",
-		rp_pio->status, rp_pio->mask);
+		status, mask);
+
+	dpc->rp_pio_status = status;
 
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SEVERITY, &sev);
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SYSERROR, &syserr);
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_EXCEPTION, &exc);
 	dev_err(dev, "RP PIO severity=%#010x, syserror=%#010x, exception=%#010x\n",
-		rp_pio->severity, rp_pio->syserror, rp_pio->exception);
+		sev, syserr, exc);
 
-	status = (rp_pio->status & ~rp_pio->mask);
+	/* Get First Error Pointer */
+	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &dpc_status);
+	first_error = (dpc_status & 0x1f00) >> 8;
 
+	status &= ~mask;
 	for (i = 0; i < ARRAY_SIZE(rp_pio_error_string); i++) {
-		if (!(status & (1 << i)))
-			continue;
-
-		dev_err(dev, "[%2d] %s%s\n", i, rp_pio_error_string[i],
-			rp_pio->first_error == i ? " (First)" : "");
+		if (status & (1 << i))
+			dev_err(dev, "[%2d] %s%s\n", i, rp_pio_error_string[i],
+				first_error == i ? " (First)" : "");
 	}
 
-	dpc_rp_pio_print_tlp_header(dev, &rp_pio->header_log);
-	if (rp_pio->log_size == 4)
+	if (dpc->rp_log_size < 4)
 		return;
-	dev_err(dev, "RP PIO ImpSpec Log %#010x\n", rp_pio->impspec_log);
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG,
+			      &dw0);
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 4,
+			      &dw1);
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 8,
+			      &dw2);
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 12,
+			      &dw3);
+	dev_err(dev, "TLP Header: %#010x %#010x %#010x %#010x\n",
+		dw0, dw1, dw2, dw3);
 
-	for (i = 0; i < rp_pio->log_size - 5; i++)
-		dev_err(dev, "TLP Prefix Header: dw%d, %#010x\n", i,
-			rp_pio->tlp_prefix_log[i]);
+	if (dpc->rp_log_size < 5)
+		return;
+	pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG, &log);
+	dev_err(dev, "RP PIO ImpSpec Log %#010x\n", log);
+
+	for (i = 0; i < dpc->rp_log_size - 5; i++) {
+		pci_read_config_dword(pdev,
+			cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG, &prefix);
+		dev_err(dev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix);
+	}
 }
 
-static void dpc_rp_pio_get_info(struct dpc_dev *dpc,
-				struct dpc_rp_pio_regs *rp_pio)
+static irqreturn_t dpc_irq(int irq, void *context)
 {
+	struct dpc_dev *dpc = (struct dpc_dev *)context;
 	struct pci_dev *pdev = dpc->dev->port;
 	struct device *dev = &dpc->dev->device;
-	int i;
-	u16 cap;
-	u16 status;
-
-	pci_read_config_dword(pdev, dpc->cap_pos + PCI_EXP_DPC_RP_PIO_STATUS,
-			      &rp_pio->status);
-	pci_read_config_dword(pdev, dpc->cap_pos + PCI_EXP_DPC_RP_PIO_MASK,
-			      &rp_pio->mask);
-
-	pci_read_config_dword(pdev, dpc->cap_pos + PCI_EXP_DPC_RP_PIO_SEVERITY,
-			      &rp_pio->severity);
-	pci_read_config_dword(pdev, dpc->cap_pos + PCI_EXP_DPC_RP_PIO_SYSERROR,
-			      &rp_pio->syserror);
-	pci_read_config_dword(pdev, dpc->cap_pos + PCI_EXP_DPC_RP_PIO_EXCEPTION,
-			      &rp_pio->exception);
+	u16 cap = dpc->cap_pos, ctl, status, source, reason, ext_reason;
 
-	/* Get First Error Pointer */
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_STATUS, &status);
-	rp_pio->first_error = (status & 0x1f00) >> 8;
+	pci_read_config_word(pdev, cap + PCI_EXP_DPC_CTL, &ctl);
 
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CAP, &cap);
-	rp_pio->log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
-	if (rp_pio->log_size < 4 || rp_pio->log_size > 9) {
-		dev_err(dev, "RP PIO log size %u is invalid\n",
-			rp_pio->log_size);
-		return;
-	}
-
-	pci_read_config_dword(pdev,
-			      dpc->cap_pos + PCI_EXP_DPC_RP_PIO_HEADER_LOG,
-			      &rp_pio->header_log.dw0);
-	pci_read_config_dword(pdev,
-			      dpc->cap_pos + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 4,
-			      &rp_pio->header_log.dw1);
-	pci_read_config_dword(pdev,
-			      dpc->cap_pos + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 8,
-			      &rp_pio->header_log.dw2);
-	pci_read_config_dword(pdev,
-			      dpc->cap_pos + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 12,
-			      &rp_pio->header_log.dw3);
-	if (rp_pio->log_size == 4)
-		return;
-
-	pci_read_config_dword(pdev,
-			      dpc->cap_pos + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG,
-			      &rp_pio->impspec_log);
-	for (i = 0; i < rp_pio->log_size - 5; i++)
-		pci_read_config_dword(pdev,
-			dpc->cap_pos + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG,
-			&rp_pio->tlp_prefix_log[i]);
-}
+	if (!(ctl & PCI_EXP_DPC_CTL_INT_EN) || ctl == (u16)(~0))
+		return IRQ_NONE;
 
-static void dpc_process_rp_pio_error(struct dpc_dev *dpc)
-{
-	struct dpc_rp_pio_regs rp_pio_regs;
+	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
 
-	dpc_rp_pio_get_info(dpc, &rp_pio_regs);
-	dpc_rp_pio_print_error(dpc, &rp_pio_regs);
+	if (!(status & PCI_EXP_DPC_STATUS_INTERRUPT))
+		return IRQ_NONE;
 
-	dpc->rp_pio_status = rp_pio_regs.status;
-}
+	if (!(status & PCI_EXP_DPC_STATUS_TRIGGER)) {
+		pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,
+				      PCI_EXP_DPC_STATUS_INTERRUPT);
+		return IRQ_HANDLED;
+	}
 
-static irqreturn_t dpc_irq(int irq, void *context)
-{
-	struct dpc_dev *dpc = (struct dpc_dev *)context;
-	struct pci_dev *pdev = dpc->dev->port;
-	struct device *dev = &dpc->dev->device;
-	u16 status, source;
+	pci_write_config_word(pdev, cap + PCI_EXP_DPC_CTL,
+			      ctl & ~PCI_EXP_DPC_CTL_INT_EN);
 
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_STATUS, &status);
-	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_SOURCE_ID,
+	pci_read_config_word(pdev, cap + PCI_EXP_DPC_SOURCE_ID,
 			     &source);
-	if (!status || status == (u16)(~0))
-		return IRQ_NONE;
 
 	dev_info(dev, "DPC containment event, status:%#06x source:%#06x\n",
 		status, source);
 
-	if (status & PCI_EXP_DPC_STATUS_TRIGGER) {
-		u16 reason = (status >> 1) & 0x3;
-		u16 ext_reason = (status >> 5) & 0x3;
-
-		dev_warn(dev, "DPC %s detected, remove downstream devices\n",
-			 (reason == 0) ? "unmasked uncorrectable error" :
-			 (reason == 1) ? "ERR_NONFATAL" :
-			 (reason == 2) ? "ERR_FATAL" :
-			 (ext_reason == 0) ? "RP PIO error" :
-			 (ext_reason == 1) ? "software trigger" :
-					     "reserved error");
-		/* show RP PIO error detail information */
-		if (reason == 3 && ext_reason == 0)
-			dpc_process_rp_pio_error(dpc);
-
-		schedule_work(&dpc->work);
-	}
+	reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN) >> 1;
+	ext_reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN_EXT) >> 5;
+
+	dev_warn(dev, "DPC %s detected, remove downstream devices\n",
+		 (reason == 0) ? "unmasked uncorrectable error" :
+		 (reason == 1) ? "ERR_NONFATAL" :
+		 (reason == 2) ? "ERR_FATAL" :
+		 (ext_reason == 0) ? "RP PIO error" :
+		 (ext_reason == 1) ? "software trigger" :
+				     "reserved error");
+	/* show RP PIO error detail information */
+	if (dpc->rp_extensions && reason == 3 && ext_reason == 0)
+		dpc_process_rp_pio_error(dpc);
+
+	schedule_work(&dpc->work);
+
 	return IRQ_HANDLED;
 }
 
@@ -289,13 +239,16 @@ static int dpc_probe(struct pcie_device *dev)
 	int status;
 	u16 ctl, cap;
 
+	if (pcie_aer_get_firmware_first(pdev))
+		return -ENOTSUPP;
+
 	dpc = devm_kzalloc(device, sizeof(*dpc), GFP_KERNEL);
 	if (!dpc)
 		return -ENOMEM;
 
 	dpc->cap_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC);
 	dpc->dev = dev;
-	INIT_WORK(&dpc->work, interrupt_event_handler);
+	INIT_WORK(&dpc->work, dpc_work);
 	set_service_data(dev, dpc);
 
 	status = devm_request_irq(device, dev->irq, dpc_irq, IRQF_SHARED,
@@ -309,15 +262,23 @@ static int dpc_probe(struct pcie_device *dev)
 	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CAP, &cap);
 	pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
 
-	dpc->rp = (cap & PCI_EXP_DPC_CAP_RP_EXT);
+	dpc->rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT);
+	if (dpc->rp_extensions) {
+		dpc->rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8;
+		if (dpc->rp_log_size < 4 || dpc->rp_log_size > 9) {
+			dev_err(device, "RP PIO log size %u is invalid\n",
+				dpc->rp_log_size);
+			dpc->rp_log_size = 0;
+		}
+	}
 
 	ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_NONFATAL | PCI_EXP_DPC_CTL_INT_EN;
 	pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
 
 	dev_info(device, "DPC error containment capabilities: Int Msg #%d, RPExt%c PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n",
-		cap & 0xf, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT),
+		cap & PCI_EXP_DPC_IRQ, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT),
 		FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP),
-		FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), (cap >> 8) & 0xf,
+		FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), dpc->rp_log_size,
 		FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE));
 	return status;
 }

+ 2 - 2
drivers/pci/pcie/portdrv_core.c

@@ -216,9 +216,9 @@ static int get_port_device_capability(struct pci_dev *dev)
 		return 0;
 
 	cap_mask = PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP
-			| PCIE_PORT_SERVICE_VC | PCIE_PORT_SERVICE_DPC;
+			| PCIE_PORT_SERVICE_VC;
 	if (pci_aer_available())
-		cap_mask |= PCIE_PORT_SERVICE_AER;
+		cap_mask |= PCIE_PORT_SERVICE_AER | PCIE_PORT_SERVICE_DPC;
 
 	if (pcie_ports_auto)
 		pcie_port_platform_notify(dev, &cap_mask);

+ 13 - 11
include/uapi/linux/pci_regs.h

@@ -966,26 +966,28 @@
 
 /* Downstream Port Containment */
 #define PCI_EXP_DPC_CAP			4	/* DPC Capability */
-#define PCI_EXP_DPC_IRQ			0x1f	/* DPC Interrupt Message Number */
-#define  PCI_EXP_DPC_CAP_RP_EXT		0x20	/* Root Port Extensions for DPC */
-#define  PCI_EXP_DPC_CAP_POISONED_TLP	0x40	/* Poisoned TLP Egress Blocking Supported */
-#define  PCI_EXP_DPC_CAP_SW_TRIGGER	0x80	/* Software Triggering Supported */
-#define  PCI_EXP_DPC_RP_PIO_LOG_SIZE	0xF00	/* RP PIO log size */
+#define PCI_EXP_DPC_IRQ			0x001F	/* Interrupt Message Number */
+#define  PCI_EXP_DPC_CAP_RP_EXT		0x0020	/* Root Port Extensions */
+#define  PCI_EXP_DPC_CAP_POISONED_TLP	0x0040	/* Poisoned TLP Egress Blocking Supported */
+#define  PCI_EXP_DPC_CAP_SW_TRIGGER	0x0080	/* Software Triggering Supported */
+#define  PCI_EXP_DPC_RP_PIO_LOG_SIZE	0x0F00	/* RP PIO Log Size */
 #define  PCI_EXP_DPC_CAP_DL_ACTIVE	0x1000	/* ERR_COR signal on DL_Active supported */
 
 #define PCI_EXP_DPC_CTL			6	/* DPC control */
-#define  PCI_EXP_DPC_CTL_EN_NONFATAL 	0x02	/* Enable trigger on ERR_NONFATAL message */
-#define  PCI_EXP_DPC_CTL_INT_EN 	0x08	/* DPC Interrupt Enable */
+#define  PCI_EXP_DPC_CTL_EN_NONFATAL 	0x0002	/* Enable trigger on ERR_NONFATAL message */
+#define  PCI_EXP_DPC_CTL_INT_EN 	0x0008	/* DPC Interrupt Enable */
 
 #define PCI_EXP_DPC_STATUS		8	/* DPC Status */
-#define  PCI_EXP_DPC_STATUS_TRIGGER	0x01	/* Trigger Status */
-#define  PCI_EXP_DPC_STATUS_INTERRUPT	0x08	/* Interrupt Status */
-#define  PCI_EXP_DPC_RP_BUSY		0x10	/* Root Port Busy */
+#define  PCI_EXP_DPC_STATUS_TRIGGER	    0x0001 /* Trigger Status */
+#define  PCI_EXP_DPC_STATUS_TRIGGER_RSN	    0x0006 /* Trigger Reason */
+#define  PCI_EXP_DPC_STATUS_INTERRUPT	    0x0008 /* Interrupt Status */
+#define  PCI_EXP_DPC_RP_BUSY		    0x0010 /* Root Port Busy */
+#define  PCI_EXP_DPC_STATUS_TRIGGER_RSN_EXT 0x0060 /* Trig Reason Extension */
 
 #define PCI_EXP_DPC_SOURCE_ID		10	/* DPC Source Identifier */
 
 #define PCI_EXP_DPC_RP_PIO_STATUS	 0x0C	/* RP PIO Status */
-#define PCI_EXP_DPC_RP_PIO_MASK		 0x10	/* RP PIO MASK */
+#define PCI_EXP_DPC_RP_PIO_MASK		 0x10	/* RP PIO Mask */
 #define PCI_EXP_DPC_RP_PIO_SEVERITY	 0x14	/* RP PIO Severity */
 #define PCI_EXP_DPC_RP_PIO_SYSERROR	 0x18	/* RP PIO SysError */
 #define PCI_EXP_DPC_RP_PIO_EXCEPTION	 0x1C	/* RP PIO Exception */