From: Prarit Bhargava <prarit@redhat.com>
Date: Mon, 30 Mar 2009 08:09:55 -0400
Subject: [pci] add pci*_selected_region/pci_enable_device_io|mem
Message-id: 20090330120953.29177.26767.sendpatchset@prarit.bos.redhat.com
O-Subject: [RHEL5 PATCH 1/5]: pci - add pci*_selected_region() and pci_enable_device_{io|mem} functions
Bugzilla: 442007
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>
RH-Acked-by: Andy Gospodarek <gospo@redhat.com>
RH-Acked-by: David Miller <davem@redhat.com>
RH-Acked-by: Tomas Henzl <thenzl@redhat.com>

Backport of c87deff776feacd05a7411097e8c8c57e549e638 and
b718989da7cf1f77ed5665dba0d2c73bd9dfe2d7, which add pci*_selected_region and
pci_enable_device_{io|mem} functions to RHEL5.

Resolves BZ 442007.

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index efcdb65..cd382e3 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -632,6 +632,62 @@ pci_enable_device_bars(struct pci_dev *dev, int bars)
 	return 0;
 }
 
+static int do_pci_enable_device(struct pci_dev *dev, int bars)
+{
+	int err;
+	err = pci_enable_device_bars(dev, bars);
+	if (err)
+		return err;
+	pci_fixup_device(pci_fixup_enable, dev);
+
+	return 0;
+}
+
+static int __pci_enable_device_flags(struct pci_dev *dev,
+				     resource_size_t flags)
+{
+	int err;
+	int i, bars = 0;
+
+	if (dev->is_enabled)
+		return 0;		/* already enabled */
+
+	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
+		if (dev->resource[i].flags & flags)
+			bars |= (1 << i);
+
+	err = do_pci_enable_device(dev, bars);
+	if (err < 0)
+		dev->is_enabled = 0;
+	return err;
+}
+
+/**
+ * pci_enable_device_io - Initialize a device for use with IO space
+ * @dev: PCI device to be initialized
+ *
+ *  Initialize device before it's used by a driver. Ask low-level code
+ *  to enable I/O resources. Wake up the device if it was suspended.
+ *  Beware, this function can fail.
+ */
+int pci_enable_device_io(struct pci_dev *dev)
+{
+	return __pci_enable_device_flags(dev, IORESOURCE_IO);
+}
+
+/**
+ * pci_enable_device_mem - Initialize a device for use with Memory space
+ * @dev: PCI device to be initialized
+ *
+ *  Initialize device before it's used by a driver. Ask low-level code
+ *  to enable Memory resources. Wake up the device if it was suspended.
+ *  Beware, this function can fail.
+ */
+int pci_enable_device_mem(struct pci_dev *dev)
+{
+	return __pci_enable_device_flags(dev, IORESOURCE_MEM);
+}
+
 /**
  * pci_enable_device - Initialize device before it's used by a driver.
  * @dev: PCI device to be initialized
@@ -639,21 +695,14 @@ pci_enable_device_bars(struct pci_dev *dev, int bars)
  *  Initialize device before it's used by a driver. Ask low-level code
  *  to enable I/O and memory. Wake up the device if it was suspended.
  *  Beware, this function can fail.
+ *
+ *  Note we don't actually enable the device many times if we call
+ *  this function repeatedly.
  */
 int
 pci_enable_device(struct pci_dev *dev)
 {
-	int err;
-
-	if (dev->is_enabled)
-		return 0;
-
-	err = pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
-	if (err)
-		return err;
-	pci_fixup_device(pci_fixup_enable, dev);
-	dev->is_enabled = 1;
-	return 0;
+	return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO);
 }
 
 /*
@@ -972,6 +1021,47 @@ err_out:
 	return -EBUSY;
 }
 
+/**
+ * pci_release_selected_regions - Release selected PCI I/O and memory resources
+ * @pdev: PCI device whose resources were previously reserved
+ * @bars: Bitmask of BARs to be released
+ *
+ * Release selected PCI I/O and memory resources previously reserved.
+ * Call this function only after all use of the PCI regions has ceased.
+ */
+void pci_release_selected_regions(struct pci_dev *pdev, int bars)
+{
+	int i;
+
+	for (i = 0; i < 6; i++)
+		if (bars & (1 << i))
+			pci_release_region(pdev, i);
+}
+
+/**
+ * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
+ * @pdev: PCI device whose resources are to be reserved
+ * @bars: Bitmask of BARs to be requested
+ * @res_name: Name to be associated with resource
+ */
+int pci_request_selected_regions(struct pci_dev *pdev, int bars,
+				 const char *res_name)
+{
+	int i;
+
+	for (i = 0; i < 6; i++)
+		if (bars & (1 << i))
+			if(pci_request_region(pdev, i, res_name))
+				goto err_out;
+	return 0;
+
+err_out:
+	while(--i >= 0)
+		if (bars & (1 << i))
+			pci_release_region(pdev, i);
+
+	return -EBUSY;
+}
 
 /**
  *	pci_release_regions - Release reserved PCI I/O and memory resources
@@ -984,10 +1074,7 @@ err_out:
 
 void pci_release_regions(struct pci_dev *pdev)
 {
-	int i;
-	
-	for (i = 0; i < 6; i++)
-		pci_release_region(pdev, i);
+	pci_release_selected_regions(pdev, (1 << 6) - 1);
 }
 
 /**
@@ -1005,18 +1092,7 @@ void pci_release_regions(struct pci_dev *pdev)
  */
 int pci_request_regions(struct pci_dev *pdev, const char *res_name)
 {
-	int i;
-	
-	for (i = 0; i < 6; i++)
-		if(pci_request_region(pdev, i, res_name))
-			goto err_out;
-	return 0;
-
-err_out:
-	while(--i >= 0)
-		pci_release_region(pdev, i);
-		
-	return -EBUSY;
+	return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
 }
 
 /**
@@ -1376,6 +1452,22 @@ out:
 }
 EXPORT_SYMBOL(pcie_set_readrq);
 
+/**
+ * pci_select_bars - Make BAR mask from the type of resource
+ * @pdev: the PCI device for which BAR mask is made
+ * @flags: resource type mask to be selected
+ *
+ * This helper routine makes bar mask from the type of resource.
+ */
+int pci_select_bars(struct pci_dev *dev, unsigned long flags)
+{
+	int i, bars = 0;
+	for (i = 0; i < PCI_NUM_RESOURCES; i++)
+		if (pci_resource_flags(dev, i) & flags)
+			bars |= (1 << i);
+	return bars;
+}
+
 static int __devinit pci_init(void)
 {
 	struct pci_dev *dev = NULL;
@@ -1417,6 +1509,8 @@ EXPORT_SYMBOL(isa_bridge);
 
 EXPORT_SYMBOL_GPL(pci_restore_bars);
 EXPORT_SYMBOL(pci_enable_device_bars);
+EXPORT_SYMBOL(pci_enable_device_io);
+EXPORT_SYMBOL(pci_enable_device_mem);
 EXPORT_SYMBOL(pci_enable_device);
 EXPORT_SYMBOL(pcim_enable_device);
 EXPORT_SYMBOL(pcim_pin_device);
@@ -1427,6 +1521,8 @@ EXPORT_SYMBOL(pci_release_regions);
 EXPORT_SYMBOL(pci_request_regions);
 EXPORT_SYMBOL(pci_release_region);
 EXPORT_SYMBOL(pci_request_region);
+EXPORT_SYMBOL(pci_release_selected_regions);
+EXPORT_SYMBOL(pci_request_selected_regions);
 EXPORT_SYMBOL(pci_set_master);
 EXPORT_SYMBOL(pci_set_mwi);
 EXPORT_SYMBOL(pci_try_set_mwi);
@@ -1436,6 +1532,7 @@ EXPORT_SYMBOL(pci_set_dma_mask);
 EXPORT_SYMBOL(pci_set_consistent_dma_mask);
 EXPORT_SYMBOL(pci_assign_resource);
 EXPORT_SYMBOL(pci_find_parent_resource);
+EXPORT_SYMBOL(pci_select_bars);
 
 EXPORT_SYMBOL(pci_set_power_state);
 EXPORT_SYMBOL(pci_save_state);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 42d636a..736aa36 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -545,6 +545,8 @@ static inline int pci_is_managed(struct pci_dev *pdev)
 
 int pci_enable_device(struct pci_dev *dev);
 int pci_enable_device_bars(struct pci_dev *dev, int mask);
+int pci_enable_device_io(struct pci_dev *dev);
+int pci_enable_device_mem(struct pci_dev *dev);
 void pci_disable_device(struct pci_dev *dev);
 void pci_set_master(struct pci_dev *dev);
 int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state);
@@ -563,6 +565,7 @@ void pci_update_resource(struct pci_dev *dev, struct resource *res, int resno);
 int pci_assign_resource(struct pci_dev *dev, int i);
 int pci_assign_resource_fixed(struct pci_dev *dev, int i);
 void pci_restore_bars(struct pci_dev *dev);
+int pci_select_bars(struct pci_dev *dev, unsigned long flags);
 
 /* ROM control related routines */
 void __iomem __must_check *pci_map_rom(struct pci_dev *pdev, size_t *size);
@@ -591,6 +594,8 @@ int pci_request_regions(struct pci_dev *, const char *);
 void pci_release_regions(struct pci_dev *);
 int pci_request_region(struct pci_dev *, int, const char *);
 void pci_release_region(struct pci_dev *, int);
+int pci_request_selected_regions(struct pci_dev *, int, const char *);
+void pci_release_selected_regions(struct pci_dev *, int);
 
 /* drivers/pci/bus.c */
 int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,