acrn-kernel/arch/mips/gt64120/common/pci.c

148 lines
5.7 KiB
C

/*
* BRIEF MODULE DESCRIPTION
* Galileo Evaluation Boards PCI support.
*
* The general-purpose functions to read/write and configure the GT64120A's
* PCI registers (function names start with pci0 or pci1) are either direct
* copies of functions written by Galileo Technology, or are modifications
* of their functions to work with Linux 2.4 vs Linux 2.2. These functions
* are Copyright - Galileo Technology.
*
* Other functions are derived from other MIPS PCI implementations, or were
* written by RidgeRun, Inc, Copyright (C) 2000 RidgeRun, Inc.
* glonnon@ridgerun.com, skranz@ridgerun.com, stevej@ridgerun.com
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <asm/gt64120.h>
#define SELF 0
/*
* pciXReadConfigReg - Read from a PCI configuration register
* - Make sure the GT is configured as a master before
* reading from another device on the PCI.
* - The function takes care of Big/Little endian conversion.
* INPUTS: regOffset: The register offset as it apears in the GT spec (or PCI
* spec)
* pciDevNum: The device number needs to be addressed.
* RETURNS: data , if the data == 0xffffffff check the master abort bit in the
* cause register to make sure the data is valid
*
* Configuration Address 0xCF8:
*
* 31 30 24 23 16 15 11 10 8 7 2 0 <=bit Number
* |congif|Reserved| Bus |Device|Function|Register|00|
* |Enable| |Number|Number| Number | Number | | <=field Name
*
*/
static unsigned int pci0ReadConfigReg(int offset, struct pci_dev *device)
{
unsigned int DataForRegCf8;
unsigned int data;
DataForRegCf8 = ((PCI_SLOT(device->devfn) << 11) |
(PCI_FUNC(device->devfn) << 8) |
(offset & ~0x3)) | 0x80000000;
GT_WRITE(GT_PCI0_CFGADDR_OFS, DataForRegCf8);
/*
* The casual observer might wonder why the READ is duplicated here,
* rather than immediately following the WRITE, and just have the swap
* in the "if". That's because there is a latency problem with trying
* to read immediately after setting up the address register. The "if"
* check gives enough time for the address to stabilize, so the READ
* can work.
*/
if (PCI_SLOT(device->devfn) == SELF) /* This board */
return GT_READ(GT_PCI0_CFGDATA_OFS);
else /* PCI is little endian so swap the Data. */
return __GT_READ(GT_PCI0_CFGDATA_OFS);
}
/*
* pciXWriteConfigReg - Write to a PCI configuration register
* - Make sure the GT is configured as a master before
* writingto another device on the PCI.
* - The function takes care of Big/Little endian conversion.
* Inputs: unsigned int regOffset: The register offset as it apears in the
* GT spec
* (or any other PCI device spec)
* pciDevNum: The device number needs to be addressed.
*
* Configuration Address 0xCF8:
*
* 31 30 24 23 16 15 11 10 8 7 2 0 <=bit Number
* |congif|Reserved| Bus |Device|Function|Register|00|
* |Enable| |Number|Number| Number | Number | | <=field Name
*
*/
static void pci0WriteConfigReg(unsigned int offset,
struct pci_dev *device, unsigned int data)
{
unsigned int DataForRegCf8;
DataForRegCf8 = ((PCI_SLOT(device->devfn) << 11) |
(PCI_FUNC(device->devfn) << 8) |
(offset & ~0x3)) | 0x80000000;
GT_WRITE(GT_PCI0_CFGADDR_OFS, DataForRegCf8);
if (PCI_SLOT(device->devfn) == SELF) /* This board */
GT_WRITE(GT_PCI0_CFGDATA_OFS, data);
else /* configuration Transaction over the pci. */
__GT_WRITE(GT_PCI0_CFGDATA_OFS, data);
}
extern struct pci_ops gt64120_pci_ops;
void __init pcibios_init(void)
{
u32 tmp;
struct pci_dev controller;
controller.devfn = SELF;
tmp = GT_READ(GT_PCI0_CMD_OFS); /* Huh??? -- Ralf */
tmp = GT_READ(GT_PCI0_BARE_OFS);
/*
* You have to enable bus mastering to configure any other
* card on the bus.
*/
tmp = pci0ReadConfigReg(PCI_COMMAND, &controller);
tmp |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_SERR;
pci0WriteConfigReg(PCI_COMMAND, &controller, tmp);
/*
* Reset PCI I/O and PCI MEM values to ones supported by EVM.
*/
ioport_resource.start = GT_PCI_IO_BASE;
ioport_resource.end = GT_PCI_IO_BASE + GT_PCI_IO_SIZE - 1;
iomem_resource.start = GT_PCI_MEM_BASE;
iomem_resource.end = GT_PCI_MEM_BASE + GT_PCI_MEM_SIZE - 1;
pci_scan_bus(0, &gt64120_pci_ops, NULL);
}