Merge branch...

Merge branch 'PCI-Add-and-use-constant-PCI_STATUS_ERROR_BITS-and-helper-pci_status_get_and_clear_errors'

Heiner Kallweit says:

====================
PCI: Add and use constant PCI_STATUS_ERROR_BITS and helper pci_status_get_and_clear_errors

Several drivers have own definitions for this constant, so move it
to the PCI core. In addition in multiple places the following code
sequence is used:
1. Read PCI_STATUS
2. Mask out non-error bits
3. Action based on set error bits
4. Write back set error bits to clear them

As this is a repeated pattern, add a helper to the PCI core.

Most affected drivers are network drivers. But as it's about core
PCI functionality, I suppose the series should go through the PCI
tree.

v2:
- fix formal issue with cover letter
v3:
- fix dumb typo in patch 7
v4:
- add patches 1-3
- move new constant PCI_STATUS_ERROR_BITS to include/linux/pci.h
- small improvements in commit messages
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/skge.h

@@ -15,12 +15,6 @@
 #define  PCI_VPD_ROM_SZ	7L<<14	/* VPD ROM size 0=256, 1=512, ... */
 #define  PCI_REV_DESC	1<<2	/* Reverse Descriptor bytes */
 
-#define PCI_STATUS_ERROR_BITS (PCI_STATUS_DETECTED_PARITY | \
-			       PCI_STATUS_SIG_SYSTEM_ERROR | \
-			       PCI_STATUS_REC_MASTER_ABORT | \
-			       PCI_STATUS_REC_TARGET_ABORT | \
-			       PCI_STATUS_PARITY)
-
 enum csr_regs {
 	B0_RAP	= 0x0000,
 	B0_CTST	= 0x0004,

drivers/net/ethernet/marvell/sky2.h

@@ -252,12 +252,6 @@ enum {
 };
 
 
-#define PCI_STATUS_ERROR_BITS (PCI_STATUS_DETECTED_PARITY | \
-			       PCI_STATUS_SIG_SYSTEM_ERROR | \
-			       PCI_STATUS_REC_MASTER_ABORT | \
-			       PCI_STATUS_REC_TARGET_ABORT | \
-			       PCI_STATUS_PARITY)
-
 enum csr_regs {
 	B0_RAP		= 0x0000,
 	B0_CTST		= 0x0004,

drivers/net/ethernet/realtek/r8169_main.c

@@ -4357,13 +4357,15 @@ static void rtl8169_pcierr_interrupt(struct net_device *dev)
 {
 	struct rtl8169_private *tp = netdev_priv(dev);
 	struct pci_dev *pdev = tp->pci_dev;
-	u16 pci_status, pci_cmd;
+	int pci_status_errs;
+	u16 pci_cmd;
 
 	pci_read_config_word(pdev, PCI_COMMAND, &pci_cmd);
-	pci_read_config_word(pdev, PCI_STATUS, &pci_status);
 
-	netif_err(tp, intr, dev, "PCI error (cmd = 0x%04x, status = 0x%04x)\n",
-		  pci_cmd, pci_status);
+	pci_status_errs = pci_status_get_and_clear_errors(pdev);
+
+	netif_err(tp, intr, dev, "PCI error (cmd = 0x%04x, status_errs = 0x%04x)\n",
+		  pci_cmd, pci_status_errs);
 
 	/*
 	 * The recovery sequence below admits a very elaborated explanation:
@@ -4380,11 +4382,6 @@ static void rtl8169_pcierr_interrupt(struct net_device *dev)
 
 	pci_write_config_word(pdev, PCI_COMMAND, pci_cmd);
 
-	pci_write_config_word(pdev, PCI_STATUS,
-		pci_status & (PCI_STATUS_DETECTED_PARITY |
-		PCI_STATUS_SIG_SYSTEM_ERROR | PCI_STATUS_REC_MASTER_ABORT |
-		PCI_STATUS_REC_TARGET_ABORT | PCI_STATUS_SIG_TARGET_ABORT));
-
 	rtl_schedule_task(tp, RTL_FLAG_TASK_RESET_PENDING);
 }
 

drivers/net/ethernet/sun/cassini.c

@@ -1716,34 +1716,26 @@ static int cas_pci_interrupt(struct net_device *dev, struct cas *cp,
 	pr_cont("\n");
 
 	if (stat & PCI_ERR_OTHER) {
-		u16 cfg;
+		int pci_errs;
 
 		/* Interrogate PCI config space for the
 		 * true cause.
 		 */
-		pci_read_config_word(cp->pdev, PCI_STATUS, &cfg);
-		netdev_err(dev, "Read PCI cfg space status [%04x]\n", cfg);
-		if (cfg & PCI_STATUS_PARITY)
+		pci_errs = pci_status_get_and_clear_errors(cp->pdev);
+
+		netdev_err(dev, "PCI status errors[%04x]\n", pci_errs);
+		if (pci_errs & PCI_STATUS_PARITY)
 			netdev_err(dev, "PCI parity error detected\n");
-		if (cfg & PCI_STATUS_SIG_TARGET_ABORT)
+		if (pci_errs & PCI_STATUS_SIG_TARGET_ABORT)
 			netdev_err(dev, "PCI target abort\n");
-		if (cfg & PCI_STATUS_REC_TARGET_ABORT)
+		if (pci_errs & PCI_STATUS_REC_TARGET_ABORT)
 			netdev_err(dev, "PCI master acks target abort\n");
-		if (cfg & PCI_STATUS_REC_MASTER_ABORT)
+		if (pci_errs & PCI_STATUS_REC_MASTER_ABORT)
 			netdev_err(dev, "PCI master abort\n");
-		if (cfg & PCI_STATUS_SIG_SYSTEM_ERROR)
+		if (pci_errs & PCI_STATUS_SIG_SYSTEM_ERROR)
 			netdev_err(dev, "PCI system error SERR#\n");
-		if (cfg & PCI_STATUS_DETECTED_PARITY)
+		if (pci_errs & PCI_STATUS_DETECTED_PARITY)
 			netdev_err(dev, "PCI parity error\n");
-
-		/* Write the error bits back to clear them. */
-		cfg &= (PCI_STATUS_PARITY |
-			PCI_STATUS_SIG_TARGET_ABORT |
-			PCI_STATUS_REC_TARGET_ABORT |
-			PCI_STATUS_REC_MASTER_ABORT |
-			PCI_STATUS_SIG_SYSTEM_ERROR |
-			PCI_STATUS_DETECTED_PARITY);
-		pci_write_config_word(cp->pdev, PCI_STATUS, cfg);
 	}
 
 	/* For all PCI errors, we should reset the chip. */

drivers/net/ethernet/sun/sungem.c

@@ -545,37 +545,25 @@ static int gem_pci_interrupt(struct net_device *dev, struct gem *gp, u32 gem_sta
 	}
 
 	if (pci_estat & GREG_PCIESTAT_OTHER) {
-		u16 pci_cfg_stat;
+		int pci_errs;
 
 		/* Interrogate PCI config space for the
 		 * true cause.
 		 */
-		pci_read_config_word(gp->pdev, PCI_STATUS,
-				     &pci_cfg_stat);
-		netdev_err(dev, "Read PCI cfg space status [%04x]\n",
-			   pci_cfg_stat);
-		if (pci_cfg_stat & PCI_STATUS_PARITY)
+		pci_errs = pci_status_get_and_clear_errors(gp->pdev);
+		netdev_err(dev, "PCI status errors[%04x]\n", pci_errs);
+		if (pci_errs & PCI_STATUS_PARITY)
 			netdev_err(dev, "PCI parity error detected\n");
-		if (pci_cfg_stat & PCI_STATUS_SIG_TARGET_ABORT)
+		if (pci_errs & PCI_STATUS_SIG_TARGET_ABORT)
 			netdev_err(dev, "PCI target abort\n");
-		if (pci_cfg_stat & PCI_STATUS_REC_TARGET_ABORT)
+		if (pci_errs & PCI_STATUS_REC_TARGET_ABORT)
 			netdev_err(dev, "PCI master acks target abort\n");
-		if (pci_cfg_stat & PCI_STATUS_REC_MASTER_ABORT)
+		if (pci_errs & PCI_STATUS_REC_MASTER_ABORT)
 			netdev_err(dev, "PCI master abort\n");
-		if (pci_cfg_stat & PCI_STATUS_SIG_SYSTEM_ERROR)
+		if (pci_errs & PCI_STATUS_SIG_SYSTEM_ERROR)
 			netdev_err(dev, "PCI system error SERR#\n");
-		if (pci_cfg_stat & PCI_STATUS_DETECTED_PARITY)
+		if (pci_errs & PCI_STATUS_DETECTED_PARITY)
 			netdev_err(dev, "PCI parity error\n");
-
-		/* Write the error bits back to clear them. */
-		pci_cfg_stat &= (PCI_STATUS_PARITY |
-				 PCI_STATUS_SIG_TARGET_ABORT |
-				 PCI_STATUS_REC_TARGET_ABORT |
-				 PCI_STATUS_REC_MASTER_ABORT |
-				 PCI_STATUS_SIG_SYSTEM_ERROR |
-				 PCI_STATUS_DETECTED_PARITY);
-		pci_write_config_word(gp->pdev,
-				      PCI_STATUS, pci_cfg_stat);
 	}
 
 	/* For all PCI errors, we should reset the chip. */

drivers/net/fddi/skfp/drvfbi.c

@@ -20,7 +20,7 @@
 #include "h/supern_2.h"
 #include "h/skfbiinc.h"
 #include <linux/bitrev.h>
-#include <linux/pci_regs.h>
+#include <linux/pci.h>
 
 #ifndef	lint
 static const char ID_sccs[] = "@(#)drvfbi.c	1.63 99/02/11 (C) SK " ;
@@ -112,7 +112,7 @@ static void card_start(struct s_smc *smc)
 	 */
 	outp(ADDR(B0_TST_CTRL), TST_CFG_WRITE_ON) ;	/* enable for writes */
 	word = inpw(PCI_C(PCI_STATUS)) ;
-	outpw(PCI_C(PCI_STATUS), word | PCI_ERRBITS) ;
+	outpw(PCI_C(PCI_STATUS), word | PCI_STATUS_ERROR_BITS);
 	outp(ADDR(B0_TST_CTRL), TST_CFG_WRITE_OFF) ;	/* disable writes */
 
 	/*

drivers/net/fddi/skfp/h/skfbi.h

@@ -33,11 +33,6 @@
  */
 #define I2C_ADDR_VPD	0xA0	/* I2C address for the VPD EEPROM */ 
 
-
-#define PCI_ERRBITS	(PCI_STATUS_DETECTED_PARITY | PCI_STATUS_SIG_SYSTEM_ERROR | PCI_STATUS_REC_MASTER_ABORT | PCI_STATUS_SIG_TARGET_ABORT | PCI_STATUS_PARITY)
-
-
-
 /*
  *	Control Register File:
  *	Bank 0

drivers/pci/pci-bridge-emul.c

@@ -50,12 +50,7 @@ static const struct pci_bridge_reg_behavior pci_regs_behavior[] = {
 		       (PCI_STATUS_CAP_LIST | PCI_STATUS_66MHZ |
 			PCI_STATUS_FAST_BACK | PCI_STATUS_DEVSEL_MASK) << 16),
 		.rsvd = GENMASK(15, 10) | ((BIT(6) | GENMASK(3, 0)) << 16),
-		.w1c = (PCI_STATUS_PARITY |
-			PCI_STATUS_SIG_TARGET_ABORT |
-			PCI_STATUS_REC_TARGET_ABORT |
-			PCI_STATUS_REC_MASTER_ABORT |
-			PCI_STATUS_SIG_SYSTEM_ERROR |
-			PCI_STATUS_DETECTED_PARITY) << 16,
+		.w1c = PCI_STATUS_ERROR_BITS << 16,
 	},
 	[PCI_CLASS_REVISION / 4] = { .ro = ~0 },
 
@@ -100,12 +95,7 @@ static const struct pci_bridge_reg_behavior pci_regs_behavior[] = {
 			 PCI_STATUS_DEVSEL_MASK) << 16) |
 		       GENMASK(11, 8) | GENMASK(3, 0)),
 
-		.w1c = (PCI_STATUS_PARITY |
-			PCI_STATUS_SIG_TARGET_ABORT |
-			PCI_STATUS_REC_TARGET_ABORT |
-			PCI_STATUS_REC_MASTER_ABORT |
-			PCI_STATUS_SIG_SYSTEM_ERROR |
-			PCI_STATUS_DETECTED_PARITY) << 16,
+		.w1c = PCI_STATUS_ERROR_BITS << 16,
 
 		.rsvd = ((BIT(6) | GENMASK(4, 0)) << 16),
 	},

drivers/pci/pci.c

@@ -173,6 +173,29 @@ unsigned char pci_bus_max_busnr(struct pci_bus *bus)
 }
 EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
 
+/**
+ * pci_status_get_and_clear_errors - return and clear error bits in PCI_STATUS
+ * @pdev: the PCI device
+ *
+ * Returns error bits set in PCI_STATUS and clears them.
+ */
+int pci_status_get_and_clear_errors(struct pci_dev *pdev)
+{
+	u16 status;
+	int ret;
+
+	ret = pci_read_config_word(pdev, PCI_STATUS, &status);
+	if (ret != PCIBIOS_SUCCESSFUL)
+		return -EIO;
+
+	status &= PCI_STATUS_ERROR_BITS;
+	if (status)
+		pci_write_config_word(pdev, PCI_STATUS, status);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(pci_status_get_and_clear_errors);
+
 #ifdef CONFIG_HAS_IOMEM
 void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar)
 {

include/linux/pci.h

@@ -42,6 +42,13 @@
 
 #include <linux/pci_ids.h>
 
+#define PCI_STATUS_ERROR_BITS (PCI_STATUS_DETECTED_PARITY  | \
+			       PCI_STATUS_SIG_SYSTEM_ERROR | \
+			       PCI_STATUS_REC_MASTER_ABORT | \
+			       PCI_STATUS_REC_TARGET_ABORT | \
+			       PCI_STATUS_SIG_TARGET_ABORT | \
+			       PCI_STATUS_PARITY)
+
 /*
  * The PCI interface treats multi-function devices as independent
  * devices.  The slot/function address of each device is encoded
@@ -1203,6 +1210,7 @@ int pci_select_bars(struct pci_dev *dev, unsigned long flags);
 bool pci_device_is_present(struct pci_dev *pdev);
 void pci_ignore_hotplug(struct pci_dev *dev);
 struct pci_dev *pci_real_dma_dev(struct pci_dev *dev);
+int pci_status_get_and_clear_errors(struct pci_dev *pdev);
 
 int __printf(6, 7) pci_request_irq(struct pci_dev *dev, unsigned int nr,
 		irq_handler_t handler, irq_handler_t thread_fn, void *dev_id,

sound/pci/bt87x.c

@@ -271,13 +271,8 @@ static void snd_bt87x_free_risc(struct snd_bt87x *chip)
 
 static void snd_bt87x_pci_error(struct snd_bt87x *chip, unsigned int status)
 {
-	u16 pci_status;
+	int pci_status = pci_status_get_and_clear_errors(chip->pci);
 
-	pci_read_config_word(chip->pci, PCI_STATUS, &pci_status);
-	pci_status &= PCI_STATUS_PARITY | PCI_STATUS_SIG_TARGET_ABORT |
-		PCI_STATUS_REC_TARGET_ABORT | PCI_STATUS_REC_MASTER_ABORT |
-		PCI_STATUS_SIG_SYSTEM_ERROR | PCI_STATUS_DETECTED_PARITY;
-	pci_write_config_word(chip->pci, PCI_STATUS, pci_status);
 	if (pci_status != PCI_STATUS_DETECTED_PARITY)
 		dev_err(chip->card->dev,
 			"Aieee - PCI error! status %#08x, PCI status %#04x\n",