arch/x86/pci/broadcom_bus.c

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

File Facts

System
Linux kernel
Corpus path
arch/x86/pci/broadcom_bus.c
Extension
.c
Size
3178 bytes
Lines
113
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration 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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Read address ranges from a Broadcom CNB20LE Host Bridge
 *
 * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
 */

#include <linux/acpi.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <asm/pci_x86.h>
#include <asm/pci-direct.h>

#include "bus_numa.h"

static void __init cnb20le_res(u8 bus, u8 slot, u8 func)
{
	struct pci_root_info *info;
	struct pci_root_res *root_res;
	struct resource res;
	u16 word1, word2;
	u8 fbus, lbus;

	/* read the PCI bus numbers */
	fbus = read_pci_config_byte(bus, slot, func, 0x44);
	lbus = read_pci_config_byte(bus, slot, func, 0x45);
	info = alloc_pci_root_info(fbus, lbus, 0, 0);

	/*
	 * Add the legacy IDE ports on bus 0
	 *
	 * These do not exist anywhere in the bridge registers, AFAICT. I do
	 * not have the datasheet, so this is the best I can do.
	 */
	if (fbus == 0) {
		update_res(info, 0x01f0, 0x01f7, IORESOURCE_IO, 0);
		update_res(info, 0x03f6, 0x03f6, IORESOURCE_IO, 0);
		update_res(info, 0x0170, 0x0177, IORESOURCE_IO, 0);
		update_res(info, 0x0376, 0x0376, IORESOURCE_IO, 0);
		update_res(info, 0xffa0, 0xffaf, IORESOURCE_IO, 0);
	}

	/* read the non-prefetchable memory window */
	word1 = read_pci_config_16(bus, slot, func, 0xc0);
	word2 = read_pci_config_16(bus, slot, func, 0xc2);
	if (word1 != word2) {
		res.start = ((resource_size_t) word1 << 16) | 0x0000;
		res.end   = ((resource_size_t) word2 << 16) | 0xffff;
		res.flags = IORESOURCE_MEM;
		update_res(info, res.start, res.end, res.flags, 0);
	}

	/* read the prefetchable memory window */
	word1 = read_pci_config_16(bus, slot, func, 0xc4);
	word2 = read_pci_config_16(bus, slot, func, 0xc6);
	if (word1 != word2) {
		res.start = ((resource_size_t) word1 << 16) | 0x0000;
		res.end   = ((resource_size_t) word2 << 16) | 0xffff;
		res.flags = IORESOURCE_MEM | IORESOURCE_PREFETCH;
		update_res(info, res.start, res.end, res.flags, 0);
	}

	/* read the IO port window */
	word1 = read_pci_config_16(bus, slot, func, 0xd0);
	word2 = read_pci_config_16(bus, slot, func, 0xd2);
	if (word1 != word2) {
		res.start = word1;
		res.end   = word2;
		res.flags = IORESOURCE_IO;
		update_res(info, res.start, res.end, res.flags, 0);
	}

	/* print information about this host bridge */
	res.start = fbus;
	res.end   = lbus;
	res.flags = IORESOURCE_BUS;
	printk(KERN_INFO "CNB20LE PCI Host Bridge (domain 0000 %pR)\n", &res);

	list_for_each_entry(root_res, &info->resources, list)
		printk(KERN_INFO "host bridge window %pR\n", &root_res->res);
}

static int __init broadcom_postcore_init(void)
{
	u8 bus = 0, slot = 0;
	u32 id;
	u16 vendor, device;

Annotation

Implementation Notes