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

205 lines
6.0 KiB
C

/*
* Low-Level PCI Support for the SH7751
*
* Dustin McIntire (dustin@sensoria.com)
* Derived from arch/i386/kernel/pci-*.c which bore the message:
* (c) 1999--2000 Martin Mares <mj@ucw.cz>
*
* Ported to the new API by Paul Mundt <lethal@linux-sh.org>
* With cleanup by Paul van Gool <pvangool@mimotech.com>
*
* May be copied or modified under the terms of the GNU General Public
* License. See linux/COPYING for more information.
*
*/
#undef DEBUG
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include "pci-sh4.h"
#include <asm/addrspace.h>
#include <asm/io.h>
/*
* Initialization. Try all known PCI access methods. Note that we support
* using both PCI BIOS and direct access: in such cases, we use I/O ports
* to access config space.
*
* Note that the platform specific initialization (BSC registers, and memory
* space mapping) will be called via the platform defined function
* pcibios_init_platform().
*/
static int __init sh7751_pci_init(void)
{
unsigned int id;
int ret;
pr_debug("PCI: Starting intialization.\n");
/* check for SH7751/SH7751R hardware */
id = pci_read_reg(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;
}
if ((ret = sh4_pci_check_direct()) != 0)
return ret;
return pcibios_init_platform();
}
subsys_initcall(sh7751_pci_init);
static int __init __area_sdram_check(unsigned int area)
{
u32 word;
word = ctrl_inl(SH7751_BCR1);
/* check BCR for SDRAM in area */
if (((word >> area) & 1) == 0) {
printk("PCI: Area %d is not configured for SDRAM. BCR1=0x%x\n",
area, word);
return 0;
}
pci_write_reg(word, SH4_PCIBCR1);
word = (u16)ctrl_inw(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%x\n",
area, word);
return 0;
}
pci_write_reg(word, SH4_PCIBCR2);
return 1;
}
int __init sh7751_pcic_init(struct sh4_pci_address_map *map)
{
u32 reg;
u32 word;
/* Set the BCR's to enable PCI access */
reg = ctrl_inl(SH7751_BCR1);
reg |= 0x80000;
ctrl_outl(reg, SH7751_BCR1);
/* Turn the clocks back on (not done in reset)*/
pci_write_reg(0, SH4_PCICLKR);
/* Clear Powerdown IRQ's (not done in reset) */
word = SH4_PCIPINT_D3 | SH4_PCIPINT_D0;
pci_write_reg(word, SH4_PCIPINT);
/*
* This code is unused for some boards as it is done in the
* bootloader and doing it here means the MAC addresses loaded
* by the bootloader get lost.
*/
if (!(map->flags & SH4_PCIC_NO_RESET)) {
/* toggle PCI reset pin */
word = SH4_PCICR_PREFIX | SH4_PCICR_PRST;
pci_write_reg(word, SH4_PCICR);
/* Wait for a long time... not 1 sec. but long enough */
mdelay(100);
word = SH4_PCICR_PREFIX;
pci_write_reg(word, SH4_PCICR);
}
/* 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(word, SH7751_PCICONF1);
/* define this host as the host bridge */
word = PCI_BASE_CLASS_BRIDGE << 24;
pci_write_reg(word, SH7751_PCICONF2);
/* Set IO and Mem windows to local address
* Make PCI and local address the same for easy 1 to 1 mapping
* Window0 = map->window0.size @ non-cached area base = SDRAM
* Window1 = map->window1.size @ cached area base = SDRAM
*/
word = map->window0.size - 1;
pci_write_reg(word, SH4_PCILSR0);
word = map->window1.size - 1;
pci_write_reg(word, SH4_PCILSR1);
/* Set the values on window 0 PCI config registers */
word = P2SEGADDR(map->window0.base);
pci_write_reg(word, SH4_PCILAR0);
pci_write_reg(word, SH7751_PCICONF5);
/* Set the values on window 1 PCI config registers */
word = PHYSADDR(map->window1.base);
pci_write_reg(word, SH4_PCILAR1);
pci_write_reg(word, SH7751_PCICONF6);
/* Set the local 16MB PCI memory space window to
* the lowest PCI mapped address
*/
word = PCIBIOS_MIN_MEM & SH4_PCIMBR_MASK;
pr_debug("PCI: Setting upper bits of Memory window to 0x%x\n", word);
pci_write_reg(word , SH4_PCIMBR);
/* Map IO space into PCI IO window
* The IO window is 64K-PCIBIOS_MIN_IO in size
* IO addresses will be translated to the
* PCI IO window base address
*/
pr_debug("PCI: Mapping IO address 0x%x - 0x%x to base 0x%x\n",
PCIBIOS_MIN_IO, (64 << 10),
SH7751_PCI_IO_BASE + PCIBIOS_MIN_IO);
/* Make sure the MSB's of IO window are set to access PCI space
* correctly */
word = PCIBIOS_MIN_IO & SH4_PCIIOBR_MASK;
pr_debug("PCI: Setting upper bits of IO window to 0x%x\n", word);
pci_write_reg(word, SH4_PCIIOBR);
/* Set PCI WCRx, BCRx's, copy from BSC locations */
/* check BCR for SDRAM in specified area */
switch (map->window0.base) {
case SH7751_CS0_BASE_ADDR: word = __area_sdram_check(0); break;
case SH7751_CS1_BASE_ADDR: word = __area_sdram_check(1); break;
case SH7751_CS2_BASE_ADDR: word = __area_sdram_check(2); break;
case SH7751_CS3_BASE_ADDR: word = __area_sdram_check(3); break;
case SH7751_CS4_BASE_ADDR: word = __area_sdram_check(4); break;
case SH7751_CS5_BASE_ADDR: word = __area_sdram_check(5); break;
case SH7751_CS6_BASE_ADDR: word = __area_sdram_check(6); break;
}
if (!word)
return 0;
/* configure the wait control registers */
word = ctrl_inl(SH7751_WCR1);
pci_write_reg(word, SH4_PCIWCR1);
word = ctrl_inl(SH7751_WCR2);
pci_write_reg(word, SH4_PCIWCR2);
word = ctrl_inl(SH7751_WCR3);
pci_write_reg(word, SH4_PCIWCR3);
word = ctrl_inl(SH7751_MCR);
pci_write_reg(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();
/* 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(word, SH4_PCICR);
return 1;
}