arch/x86/pci/fixup.c

Source file repositories/reference/linux-study-clean/arch/x86/pci/fixup.c

File Facts

System
Linux kernel
Corpus path
arch/x86/pci/fixup.c
Extension
.c
Size
36489 bytes
Lines
1084
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

if (bridge && (pci_is_bridge(bridge))) {
			pci_read_config_word(bridge, PCI_BRIDGE_CONTROL,
						&config);
			if (!(config & PCI_BRIDGE_CTL_VGA))
				return;
		}
		bus = bus->parent;
	}
	if (!vga_default_device() || pdev == vga_default_device()) {
		pci_read_config_word(pdev, PCI_COMMAND, &config);
		if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
			res = &pdev->resource[PCI_ROM_RESOURCE];

			pci_disable_rom(pdev);
			if (res->parent)
				release_resource(res);

			res->start = 0xC0000;
			res->end = res->start + 0x20000 - 1;
			res->flags = IORESOURCE_MEM | IORESOURCE_ROM_SHADOW |
				     IORESOURCE_PCI_FIXED;
			dev_info(&pdev->dev, "Video device with shadowed ROM at %pR\n",
				 res);
		}
	}
}
DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID,
			       PCI_CLASS_DISPLAY_VGA, 8, pci_fixup_video);


static const struct dmi_system_id msi_k8t_dmi_table[] = {
	{
		.ident = "MSI-K8T-Neo2Fir",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
			DMI_MATCH(DMI_PRODUCT_NAME, "MS-6702E"),
		},
	},
	{}
};

/*
 * The AMD-Athlon64 board MSI "K8T Neo2-FIR" disables the onboard sound
 * card if a PCI-soundcard is added.
 *
 * The BIOS only gives options "DISABLED" and "AUTO". This code sets
 * the corresponding register-value to enable the soundcard.
 *
 * The soundcard is only enabled, if the mainboard is identified
 * via DMI-tables and the soundcard is detected to be off.
 */
static void pci_fixup_msi_k8t_onboard_sound(struct pci_dev *dev)
{
	unsigned char val;
	if (!dmi_check_system(msi_k8t_dmi_table))
		return; /* only applies to MSI K8T Neo2-FIR */

	pci_read_config_byte(dev, 0x50, &val);
	if (val & 0x40) {
		pci_write_config_byte(dev, 0x50, val & (~0x40));

		/* verify the change for status output */
		pci_read_config_byte(dev, 0x50, &val);
		if (val & 0x40)
			dev_info(&dev->dev, "Detected MSI K8T Neo2-FIR; "
					"can't enable onboard soundcard!\n");
		else
			dev_info(&dev->dev, "Detected MSI K8T Neo2-FIR; "
					"enabled onboard soundcard\n");
	}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237,
		pci_fixup_msi_k8t_onboard_sound);
DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237,
		pci_fixup_msi_k8t_onboard_sound);

/*
 * Some Toshiba laptops need extra code to enable their TI TSB43AB22/A.
 *
 * We pretend to bring them out of full D3 state, and restore the proper
 * IRQ, PCI cache line size, and BARs, otherwise the device won't function
 * properly.  In some cases, the device will generate an interrupt on
 * the wrong IRQ line, causing any devices sharing the line it's
 * *supposed* to use to be disabled by the kernel's IRQ debug code.
 */
static u16 toshiba_line_size;

static const struct dmi_system_id toshiba_ohci1394_dmi_table[] = {
	{
		.ident = "Toshiba PS5 based laptop",

Annotation

Implementation Notes