x86: Introduce pci_map_biosrom()

The isci driver needs to retrieve its preboot OROM image which contains
necessary runtime parameters like platform specific sas addresses and
phy configuration.  There is no ROM BAR associated with this area,
instead we will need to scan legacy expansion ROM space.

1/ Promote the probe_roms_32 implementation to x86-64
2/ Add a facility to find and map an adapter rom by pci device (according to
   PCI Firmware Specification Revision 3.0)

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
LKML-Reference: <20110308183226.6246.90354.stgit@localhost6.localdomain6>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 267 insertions, 0 deletions

diff --git a/arch/x86/kernel/probe_roms.c b/arch/x86/kernel/probe_roms.c
new file mode 100644
index 0000000..ba0a4cc
--- /dev/null
+++ b/arch/x86/kernel/probe_roms.c
@@ -0,0 +1,267 @@
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/mmzone.h>
+#include <linux/ioport.h>
+#include <linux/seq_file.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/edd.h>
+#include <linux/dmi.h>
+#include <linux/pfn.h>
+#include <linux/pci.h>
+#include <asm/pci-direct.h>
+
+
+#include <asm/e820.h>
+#include <asm/mmzone.h>
+#include <asm/setup.h>
+#include <asm/sections.h>
+#include <asm/io.h>
+#include <asm/setup_arch.h>
+
+static struct resource system_rom_resource = {
+	.name	= "System ROM",
+	.start	= 0xf0000,
+	.end	= 0xfffff,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+};
+
+static struct resource extension_rom_resource = {
+	.name	= "Extension ROM",
+	.start	= 0xe0000,
+	.end	= 0xeffff,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+};
+
+static struct resource adapter_rom_resources[] = { {
+	.name 	= "Adapter ROM",
+	.start	= 0xc8000,
+	.end	= 0,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+	.name 	= "Adapter ROM",
+	.start	= 0,
+	.end	= 0,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+	.name 	= "Adapter ROM",
+	.start	= 0,
+	.end	= 0,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+	.name 	= "Adapter ROM",
+	.start	= 0,
+	.end	= 0,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+	.name 	= "Adapter ROM",
+	.start	= 0,
+	.end	= 0,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+	.name 	= "Adapter ROM",
+	.start	= 0,
+	.end	= 0,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+} };
+
+static struct resource video_rom_resource = {
+	.name 	= "Video ROM",
+	.start	= 0xc0000,
+	.end	= 0xc7fff,
+	.flags	= IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+};
+
+/* does this oprom support the given pci device, or any of the devices
+ * that the driver supports?
+ */
+static bool match_id(struct pci_dev *pdev, unsigned short vendor, unsigned short device)
+{
+	struct pci_driver *drv = pdev->driver;
+	const struct pci_device_id *id;
+
+	if (pdev->vendor == vendor && pdev->device == device)
+		return true;
+
+	for (id = drv ? drv->id_table : NULL; id && id->vendor; id++)
+		if (id->vendor == vendor && id->device == device)
+			break;
+
+	return id && id->vendor;
+}
+
+static bool probe_list(struct pci_dev *pdev, unsigned short vendor,
+		       const unsigned char *rom_list)
+{
+	unsigned short device;
+
+	do {
+		if (probe_kernel_address(rom_list, device) != 0)
+			device = 0;
+
+		if (device && match_id(pdev, vendor, device))
+			break;
+
+		rom_list += 2;
+	} while (device);
+
+	return !!device;
+}
+
+static struct resource *find_oprom(struct pci_dev *pdev)
+{
+	struct resource *oprom = NULL;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(adapter_rom_resources); i++) {
+		struct resource *res = &adapter_rom_resources[i];
+		unsigned short offset, vendor, device, list, rev;
+		const unsigned char *rom;
+
+		if (res->end == 0)
+			break;
+
+		rom = isa_bus_to_virt(res->start);
+		if (probe_kernel_address(rom + 0x18, offset) != 0)
+			continue;
+
+		if (probe_kernel_address(rom + offset + 0x4, vendor) != 0)
+			continue;
+
+		if (probe_kernel_address(rom + offset + 0x6, device) != 0)
+			continue;
+
+		if (match_id(pdev, vendor, device)) {
+			oprom = res;
+			break;
+		}
+
+		if (probe_kernel_address(rom + offset + 0x8, list) == 0 &&
+		    probe_kernel_address(rom + offset + 0xc, rev) == 0 &&
+		    rev >= 3 && list &&
+		    probe_list(pdev, vendor, rom + offset + list)) {
+			oprom = res;
+			break;
+		}
+	}
+
+	return oprom;
+}
+
+void *pci_map_biosrom(struct pci_dev *pdev)
+{
+	struct resource *oprom = find_oprom(pdev);
+
+	if (!oprom)
+		return NULL;
+
+	return ioremap(oprom->start, resource_size(oprom));
+}
+EXPORT_SYMBOL(pci_map_biosrom);
+
+void pci_unmap_biosrom(void __iomem *image)
+{
+	iounmap(image);
+}
+EXPORT_SYMBOL(pci_unmap_biosrom);
+
+size_t pci_biosrom_size(struct pci_dev *pdev)
+{
+	struct resource *oprom = find_oprom(pdev);
+
+	return oprom ? resource_size(oprom) : 0;
+}
+EXPORT_SYMBOL(pci_biosrom_size);
+
+#define ROMSIGNATURE 0xaa55
+
+static int __init romsignature(const unsigned char *rom)
+{
+	const unsigned short * const ptr = (const unsigned short *)rom;
+	unsigned short sig;
+
+	return probe_kernel_address(ptr, sig) == 0 && sig == ROMSIGNATURE;
+}
+
+static int __init romchecksum(const unsigned char *rom, unsigned long length)
+{
+	unsigned char sum, c;
+
+	for (sum = 0; length && probe_kernel_address(rom++, c) == 0; length--)
+		sum += c;
+	return !length && !sum;
+}
+
+void __init probe_roms(void)
+{
+	const unsigned char *rom;
+	unsigned long start, length, upper;
+	unsigned char c;
+	int i;
+
+	/* video rom */
+	upper = adapter_rom_resources[0].start;
+	for (start = video_rom_resource.start; start < upper; start += 2048) {
+		rom = isa_bus_to_virt(start);
+		if (!romsignature(rom))
+			continue;
+
+		video_rom_resource.start = start;
+
+		if (probe_kernel_address(rom + 2, c) != 0)
+			continue;
+
+		/* 0 < length <= 0x7f * 512, historically */
+		length = c * 512;
+
+		/* if checksum okay, trust length byte */
+		if (length && romchecksum(rom, length))
+			video_rom_resource.end = start + length - 1;
+
+		request_resource(&iomem_resource, &video_rom_resource);
+		break;
+	}
+
+	start = (video_rom_resource.end + 1 + 2047) & ~2047UL;
+	if (start < upper)
+		start = upper;
+
+	/* system rom */
+	request_resource(&iomem_resource, &system_rom_resource);
+	upper = system_rom_resource.start;
+
+	/* check for extension rom (ignore length byte!) */
+	rom = isa_bus_to_virt(extension_rom_resource.start);
+	if (romsignature(rom)) {
+		length = extension_rom_resource.end - extension_rom_resource.start + 1;
+		if (romchecksum(rom, length)) {
+			request_resource(&iomem_resource, &extension_rom_resource);
+			upper = extension_rom_resource.start;
+		}
+	}
+
+	/* check for adapter roms on 2k boundaries */
+	for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) {
+		rom = isa_bus_to_virt(start);
+		if (!romsignature(rom))
+			continue;
+
+		if (probe_kernel_address(rom + 2, c) != 0)
+			continue;
+
+		/* 0 < length <= 0x7f * 512, historically */
+		length = c * 512;
+
+		/* but accept any length that fits if checksum okay */
+		if (!length || start + length > upper || !romchecksum(rom, length))
+			continue;
+
+		adapter_rom_resources[i].start = start;
+		adapter_rom_resources[i].end = start + length - 1;
+		request_resource(&iomem_resource, &adapter_rom_resources[i]);
+
+		start = adapter_rom_resources[i++].end & ~2047UL;
+	}
+}
+