/*
* 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.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#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 <asm/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;
}
/* Set the BCR's to enable PCI access */
reg = __raw_readl(SH7751_BCR1);
reg |= 0x80000;
__raw_writel(reg, SH7751_BCR1);
/* Turn the clocks back on (not done in reset)*/
pci_write_reg(chan, 0, SH4_PCICLKR);
/* Clear Powerdown IRQ's (not done in reset) */
word = SH4_PCIPINT_D3 | SH4_PCIPINT_D0;
pci_write_reg(chan, word, SH4_PCIPINT);
/* set the command/status bits to:
* Wait Cycle Control + Parity Enable + Bus Master +
* Mem space enable
*/
word = SH7751_PCICONF1_WCC | SH7751_PCICONF1_PER |
SH7751_PCICONF1_BUM | SH7751_PCICONF1_MES;
pci_write_reg(chan, word, SH7751_PCICONF1);
/* define this host as the host bridge */
word = PCI_BASE_CLASS_BRIDGE << 24;
pci_write_reg(chan, word, SH7751_PCICONF2);
/* Set IO and Mem windows to local address
* Make PCI and local address the same for easy 1 to 1 mapping
*/
word = sh7751_pci_map.window0.size - 1;
pci_write_reg(chan, word, SH4_PCILSR0);
/* Set the values on window 0 PCI config registers */
word = P2SEGADDR(sh7751_pci_map.window0.base);
pci_write_reg(chan, word, SH4_PCILAR0);
pci_write_reg(chan, word, SH7751_PCICONF5);
/* Set the local 16MB PCI memory space window to
* the lowest PCI mapped address
*/
word = chan->resources[1].start & SH4_PCIMBR_MASK;
pr_debug("PCI: Setting upper bits of Memory window to 0x%x\n", word);
pci_write_reg(chan, word , SH4_PCIMBR);
/* Make sure the MSB's of IO window are set to access PCI space
* correctly */
word = chan->resources[0].start & SH4_PCIIOBR_MASK;
pr_debug("PCI: Setting upper bits of IO window to 0x%x\n", word);
pci_write_reg(chan, word, SH4_PCIIOBR);
/* Set PCI WCRx, BCRx's, copy from BSC locations */
/* check BCR for SDRAM in specified area */
switch (sh7751_pci_map.window0.base) {
case SH7751_CS0_BASE_ADDR: word = __area_sdram_check(chan, 0); break;
case SH7751_CS1_BASE_ADDR: word = __area_sdram_check(chan, 1); break;
case SH7751_CS2_BASE_ADDR: word = __area_sdram_check(chan, 2); break;
case SH7751_CS3_BASE_ADDR: word = __area_sdram_check(chan, 3); break;
case SH7751_CS4_BASE_ADDR: word = __area_sdram_check(chan, 4); break;
case SH7751_CS5_BASE_ADDR: word = __area_sdram_check(chan, 5); break;
case SH7751_CS6_BASE_ADDR: word = __area_sdram_check(chan, 6); break;
}
if (!word)
return -1;
/* configure the wait control registers */
word = __raw_readl(SH7751_WCR1);
pci_write_reg(chan, word, SH4_PCIWCR1);
word = __raw_readl(SH7751_WCR2);
pci_write_reg(chan, word, SH4_PCIWCR2);
word = __raw_readl(SH7751_WCR3);
pci_write_reg(chan, word, SH4_PCIWCR3);
word = __raw_readl(SH7751_MCR);
pci_write_reg(chan, word, SH4_PCIMCR);
/* NOTE: I'm ignoring the PCI error IRQs for now..
* TODO: add support for the internal error interrupts and
* DMA interrupts...
*/
pci_fixup_pcic(chan);
/* SH7751 init done, set central function init complete */
/* use round robin mode to stop a device starving/overruning */
word = SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_ARBM;
pci_write_reg(chan, word, SH4_PCICR);
return register_pci_controller(chan);
}
arch_initcall(sh7751_pci_init);
