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-rw-r--r--arch/i386/pci/Makefile2
-rw-r--r--arch/i386/pci/early.c44
2 files changed, 45 insertions, 1 deletions
diff --git a/arch/i386/pci/Makefile b/arch/i386/pci/Makefile
index 62ad75c57e6..1594d2f55c8 100644
--- a/arch/i386/pci/Makefile
+++ b/arch/i386/pci/Makefile
@@ -11,4 +11,4 @@ pci-y += legacy.o irq.o
pci-$(CONFIG_X86_VISWS) := visws.o fixup.o
pci-$(CONFIG_X86_NUMAQ) := numa.o irq.o
-obj-y += $(pci-y) common.o
+obj-y += $(pci-y) common.o early.o
diff --git a/arch/i386/pci/early.c b/arch/i386/pci/early.c
new file mode 100644
index 00000000000..b1f7f40d809
--- /dev/null
+++ b/arch/i386/pci/early.c
@@ -0,0 +1,44 @@
+#include <linux/kernel.h>
+#include <asm/pci-direct.h>
+#include <asm/io.h>
+
+/* Direct PCI access. This is used for PCI accesses in early boot before
+ the PCI subsystem works. */
+
+#define PDprintk(x...)
+
+u32 read_pci_config(u8 bus, u8 slot, u8 func, u8 offset)
+{
+ u32 v;
+ outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
+ v = inl(0xcfc);
+ if (v != 0xffffffff)
+ PDprintk("%x reading 4 from %x: %x\n", slot, offset, v);
+ return v;
+}
+
+u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset)
+{
+ u8 v;
+ outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
+ v = inb(0xcfc + (offset&3));
+ PDprintk("%x reading 1 from %x: %x\n", slot, offset, v);
+ return v;
+}
+
+u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset)
+{
+ u16 v;
+ outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
+ v = inw(0xcfc + (offset&2));
+ PDprintk("%x reading 2 from %x: %x\n", slot, offset, v);
+ return v;
+}
+
+void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
+ u32 val)
+{
+ PDprintk("%x writing to %x: %x\n", slot, offset, val);
+ outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
+ outl(val, 0xcfc);
+}