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Diffstat (limited to 'kernel/arch/x86/pci/early.c')
-rw-r--r--kernel/arch/x86/pci/early.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/kernel/arch/x86/pci/early.c b/kernel/arch/x86/pci/early.c
new file mode 100644
index 000000000..d1067d539
--- /dev/null
+++ b/kernel/arch/x86/pci/early.c
@@ -0,0 +1,111 @@
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <asm/pci-direct.h>
+#include <asm/io.h>
+#include <asm/pci_x86.h>
+
+/* Direct PCI access. This is used for PCI accesses in early boot before
+ the PCI subsystem works. */
+
+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);
+ 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));
+ 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));
+ return v;
+}
+
+void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
+ u32 val)
+{
+ outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
+ outl(val, 0xcfc);
+}
+
+void write_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset, u8 val)
+{
+ outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
+ outb(val, 0xcfc + (offset&3));
+}
+
+void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val)
+{
+ outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
+ outw(val, 0xcfc + (offset&2));
+}
+
+int early_pci_allowed(void)
+{
+ return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) ==
+ PCI_PROBE_CONF1;
+}
+
+void early_dump_pci_device(u8 bus, u8 slot, u8 func)
+{
+ int i;
+ int j;
+ u32 val;
+
+ printk(KERN_INFO "pci 0000:%02x:%02x.%d config space:",
+ bus, slot, func);
+
+ for (i = 0; i < 256; i += 4) {
+ if (!(i & 0x0f))
+ printk("\n %02x:",i);
+
+ val = read_pci_config(bus, slot, func, i);
+ for (j = 0; j < 4; j++) {
+ printk(" %02x", val & 0xff);
+ val >>= 8;
+ }
+ }
+ printk("\n");
+}
+
+void early_dump_pci_devices(void)
+{
+ unsigned bus, slot, func;
+
+ if (!early_pci_allowed())
+ return;
+
+ for (bus = 0; bus < 256; bus++) {
+ for (slot = 0; slot < 32; slot++) {
+ for (func = 0; func < 8; func++) {
+ u32 class;
+ u8 type;
+
+ class = read_pci_config(bus, slot, func,
+ PCI_CLASS_REVISION);
+ if (class == 0xffffffff)
+ continue;
+
+ early_dump_pci_device(bus, slot, func);
+
+ if (func == 0) {
+ type = read_pci_config_byte(bus, slot,
+ func,
+ PCI_HEADER_TYPE);
+ if (!(type & 0x80))
+ break;
+ }
+ }
+ }
+ }
+}