PCI/x86: early dump pci conf space v2

Allows us to dump PCI space before any kernel changes have been made.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

4 files changed, 63 insertions, 0 deletions

diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
index 6dff1286ad8a..524b6850b2c0 100644
--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -361,6 +361,11 @@ void __init setup_arch(char **cmdline_p)
 
         parse_early_param();
 
+#ifdef CONFIG_PCI
+        if (pci_early_dump_regs)
+                early_dump_pci_devices();
+#endif
+
 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
         if (init_ohci1394_dma_early)
                 init_ohci1394_dma_on_all_controllers();
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 3a5261bdff5d..d19fd07bafd6 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -20,6 +20,7 @@
 unsigned int pci_probe = PCI_PROBE_BIOS | PCI_PROBE_CONF1 | PCI_PROBE_CONF2 |
                                 PCI_PROBE_MMCONF;
 
+unsigned int pci_early_dump_regs;
 static int pci_bf_sort;
 int pci_routeirq;
 int pcibios_last_bus = -1;
@@ -511,6 +512,9 @@ char * __devinit  pcibios_setup(char *str)
         } else if (!strcmp(str, "use_crs")) {
                 pci_probe |= PCI_USE__CRS;
                 return NULL;
+        } else if (!strcmp(str, "earlydump")) {
+                pci_early_dump_regs = 1;
+                return NULL;
         } else if (!strcmp(str, "routeirq")) {
                 pci_routeirq = 1;
                 return NULL;
diff --git a/arch/x86/pci/early.c b/arch/x86/pci/early.c
index 8e2821e8dac5..858dbe3399f9 100644
--- a/arch/x86/pci/early.c
+++ b/arch/x86/pci/early.c
@@ -64,3 +64,54 @@ 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("PCI: %02x:%02x:%02x", bus, slot, func);
+
+        for (i = 0; i < 256; i += 4) {
+                if (!(i & 0x0f))
+                        printk("\n%04x:",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)
+                                        break;
+
+                                early_dump_pci_device(bus, slot, func);
+
+                                /* No multi-function device? */
+                                type = read_pci_config_byte(bus, slot, func,
+                                                               PCI_HEADER_TYPE);
+                                if (!(type & 0x80))
+                                        break;
+                        }
+                }
+        }
+}
+
diff --git a/include/asm-x86/pci-direct.h b/include/asm-x86/pci-direct.h
index 7bd40b4de751..80c775d9fe20 100644
--- a/include/asm-x86/pci-direct.h
+++ b/include/asm-x86/pci-direct.h
@@ -15,4 +15,7 @@ extern void write_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset, u16 val);
 
 extern int early_pci_allowed(void);
 
+extern unsigned int pci_early_dump_regs;
+extern void early_dump_pci_device(u8 bus, u8 slot, u8 func);
+extern void early_dump_pci_devices(void);
 #endif