arch/sh/drivers/pci/pci-sh7751.c

Source file repositories/reference/linux-study-clean/arch/sh/drivers/pci/pci-sh7751.c

File Facts

System
Linux kernel
Corpus path
arch/sh/drivers/pci/pci-sh7751.c
Extension
.c
Size
5343 bytes
Lines
180
Domain
Architecture Layer
Bucket
arch/sh
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

// SPDX-License-Identifier: GPL-2.0
/*
 * Low-Level PCI Support for the SH7751
 *
 *  Copyright (C) 2003 - 2009  Paul Mundt
 *  Copyright (C) 2001  Dustin McIntire
 *
 *  With cleanup by Paul van Gool <pvangool@mimotech.com>, 2003.
 */
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/io.h>
#include "pci-sh4.h"
#include <asm/addrspace.h>
#include <linux/sizes.h>

static int __init __area_sdram_check(struct pci_channel *chan,
				     unsigned int area)
{
	unsigned long word;

	word = __raw_readl(SH7751_BCR1);
	/* check BCR for SDRAM in area */
	if (((word >> area) & 1) == 0) {
		printk("PCI: Area %d is not configured for SDRAM. BCR1=0x%lx\n",
		       area, word);
		return 0;
	}
	pci_write_reg(chan, word, SH4_PCIBCR1);

	word = __raw_readw(SH7751_BCR2);
	/* check BCR2 for 32bit SDRAM interface*/
	if (((word >> (area << 1)) & 0x3) != 0x3) {
		printk("PCI: Area %d is not 32 bit SDRAM. BCR2=0x%lx\n",
		       area, word);
		return 0;
	}
	pci_write_reg(chan, word, SH4_PCIBCR2);

	return 1;
}

static struct resource sh7751_pci_resources[] = {
	{
		.name	= "SH7751_IO",
		.start	= 0x1000,
		.end	= SZ_4M - 1,
		.flags	= IORESOURCE_IO
	}, {
		.name	= "SH7751_mem",
		.start	= SH7751_PCI_MEMORY_BASE,
		.end	= SH7751_PCI_MEMORY_BASE + SH7751_PCI_MEM_SIZE - 1,
		.flags	= IORESOURCE_MEM
	},
};

static struct pci_channel sh7751_pci_controller = {
	.pci_ops	= &sh4_pci_ops,
	.resources	= sh7751_pci_resources,
	.nr_resources	= ARRAY_SIZE(sh7751_pci_resources),
	.mem_offset	= 0x00000000,
	.io_offset	= 0x00000000,
	.io_map_base	= SH7751_PCI_IO_BASE,
};

static struct sh4_pci_address_map sh7751_pci_map = {
	.window0	= {
		.base	= SH7751_CS3_BASE_ADDR,
		.size	= 0x04000000,
	},
};

static int __init sh7751_pci_init(void)
{
	struct pci_channel *chan = &sh7751_pci_controller;
	unsigned int id;
	u32 word, reg;

	printk(KERN_NOTICE "PCI: Starting initialization.\n");

	chan->reg_base = 0xfe200000;

	/* check for SH7751/SH7751R hardware */
	id = pci_read_reg(chan, SH7751_PCICONF0);
	if (id != ((SH7751_DEVICE_ID << 16) | SH7751_VENDOR_ID) &&
	    id != ((SH7751R_DEVICE_ID << 16) | SH7751_VENDOR_ID)) {
		pr_debug("PCI: This is not an SH7751(R) (%x)\n", id);
		return -ENODEV;

Annotation

Implementation Notes