PCI: Make PCI_ROM_ADDRESS_MASK a 32-bit constant

A 64-bit value is not needed since a PCI ROM address consists in 32 bits.
This fixes a clang warning about "implicit conversion from 'unsigned long'
to 'u32'".

Also remove now unnecessary casts to u32 from __pci_read_base() and
pci_std_update_resource().

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/probe.c

@@ -231,7 +231,7 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
 			res->flags |= IORESOURCE_ROM_ENABLE;
 		l64 = l & PCI_ROM_ADDRESS_MASK;
 		sz64 = sz & PCI_ROM_ADDRESS_MASK;
-		mask64 = (u32)PCI_ROM_ADDRESS_MASK;
+		mask64 = PCI_ROM_ADDRESS_MASK;
 	}
 
 	if (res->flags & IORESOURCE_MEM_64) {

drivers/pci/setup-res.c

@@ -63,7 +63,7 @@ static void pci_std_update_resource(struct pci_dev *dev, int resno)
 		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
 		new |= res->flags & ~PCI_BASE_ADDRESS_IO_MASK;
 	} else if (resno == PCI_ROM_RESOURCE) {
-		mask = (u32)PCI_ROM_ADDRESS_MASK;
+		mask = PCI_ROM_ADDRESS_MASK;
 	} else {
 		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
 		new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;

include/uapi/linux/pci_regs.h

@@ -114,7 +114,7 @@
 #define PCI_SUBSYSTEM_ID	0x2e
 #define PCI_ROM_ADDRESS		0x30	/* Bits 31..11 are address, 10..1 reserved */
 #define  PCI_ROM_ADDRESS_ENABLE	0x01
-#define PCI_ROM_ADDRESS_MASK	(~0x7ffUL)
+#define PCI_ROM_ADDRESS_MASK	(~0x7ffU)
 
 #define PCI_CAPABILITY_LIST	0x34	/* Offset of first capability list entry */