PCI: Make early dump functionality generic

Move early dump functionality into common code so that it is available for
all architectures. No need to carry arch-specific reads around as the read
hooks are already initialized by the time pci_setup_device() is getting
called during scan.

Tested-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Sinan Kaya <[e-mail]>
Signed-off-by: Bjorn Helgaas <[e-mail]>
Reviewed-by: Andy Shevchenko <[e-mail]>

Documentation/admin-guide/kernel-parameters.txt

···
 			See also Documentation/blockdev/paride.txt.
 
 	pci=option[,option...]	[PCI] various PCI subsystem options:
-		earlydump	[X86] dump PCI config space before the kernel
+		earlydump	dump PCI config space before the kernel
 				changes anything
 		off		[X86] don't probe for the PCI bus
 		bios		[X86-32] force use of PCI BIOS, don't access

arch/x86/include/asm/pci-direct.h

···
 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 /* _ASM_X86_PCI_DIRECT_H */

arch/x86/kernel/setup.c

···
 		setup_clear_cpu_cap(X86_FEATURE_APIC);
 	}
 
-#ifdef CONFIG_PCI
-	if (pci_early_dump_regs)
-		early_dump_pci_devices();
-#endif
-
 	e820__reserve_setup_data();
 	e820__finish_early_params();
 

arch/x86/pci/common.c

···
 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 noioapicquirk;
···
 		pci_probe |= PCI_BIG_ROOT_WINDOW;
 		return NULL;
 #endif
-	} else if (!strcmp(str, "earlydump")) {
-		pci_early_dump_regs = 1;
-		return NULL;
 	} else if (!strcmp(str, "routeirq")) {
 		pci_routeirq = 1;
 		return NULL;

arch/x86/pci/early.c

···
 			PCI_PROBE_CONF1;
 }
 
-void early_dump_pci_device(u8 bus, u8 slot, u8 func)
-{
-	u32 value[256 / 4];
-	int i;
-
-	pr_info("pci 0000:%02x:%02x.%d config space:\n", bus, slot, func);
-
-	for (i = 0; i < 256; i += 4)
-		value[i / 4] = read_pci_config(bus, slot, func, i);
-
-	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1, value, 256, false);
-}
-
-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;
-				}
-			}
-		}
-	}
-}

drivers/pci/pci.c

···
 /* If set, the PCIe ATS capability will not be used. */
 static bool pcie_ats_disabled;
 
+/* If set, the PCI config space of each device is printed during boot. */
+bool pci_early_dump;
+
 bool pci_ats_disabled(void)
 {
 	return pcie_ats_disabled;
···
 				pcie_ats_disabled = true;
 			} else if (!strcmp(str, "noaer")) {
 				pci_no_aer();
+			} else if (!strcmp(str, "earlydump")) {
+				pci_early_dump = true;
 			} else if (!strncmp(str, "realloc=", 8)) {
 				pci_realloc_get_opt(str + 8);
 			} else if (!strncmp(str, "realloc", 7)) {

drivers/pci/pci.h

···
 #define PCI_VSEC_ID_INTEL_TBT	0x1234	/* Thunderbolt */
 
 extern const unsigned char pcie_link_speed[];
+extern bool pci_early_dump;
 
 bool pcie_cap_has_lnkctl(const struct pci_dev *dev);
 

drivers/pci/probe.c

···
 	return 0;
 }
 
+static void early_dump_pci_device(struct pci_dev *pdev)
+{
+	u32 value[256 / 4];
+	int i;
+
+	pci_info(pdev, "config space:\n");
+
+	for (i = 0; i < 256; i += 4)
+		pci_read_config_dword(pdev, i, &value[i / 4]);
+
+	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1,
+		       value, 256, false);
+}
+
 /**
  * pci_setup_device - Fill in class and map information of a device
  * @dev: the device structure to fill
···
 
 	pci_printk(KERN_DEBUG, dev, "[%04x:%04x] type %02x class %#08x\n",
 		   dev->vendor, dev->device, dev->hdr_type, dev->class);
+
+	if (pci_early_dump)
+		early_dump_pci_device(dev);
 
 	/* Need to have dev->class ready */
 	dev->cfg_size = pci_cfg_space_size(dev);