ops-pmcmsp.c

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/*
 * PMC-Sierra MSP board specific pci_ops
 *
 * Copyright 2001 MontaVista Software Inc.
 * Copyright 2005-2007 PMC-Sierra, Inc
 *
 * Author: Jun Sun, [email protected] or [email protected]
 *
 * Much of the code is derived from the original DDB5074 port by
 * Geert Uytterhoeven <[email protected]>
 *
 * 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.
 *
 */

#define PCI_COUNTERS    1

#include <linux/types.h>
#include <linux/pci.h>
#include <linux/interrupt.h>

#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#endif /* CONFIG_PROC_FS && PCI_COUNTERS */

#include <linux/kernel.h>
#include <linux/init.h>

#include <asm/byteorder.h>
#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
#include <asm/mipsmtregs.h>
#endif

#include <msp_prom.h>
#include <msp_cic_int.h>
#include <msp_pci.h>
#include <msp_regs.h>
#include <msp_regops.h>

#define PCI_ACCESS_READ     0
#define PCI_ACCESS_WRITE    1

#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
static char proc_init;
extern struct proc_dir_entry *proc_bus_pci_dir;
unsigned int pci_int_count[32];

static void pci_proc_init(void);

/*****************************************************************************
 *
 *  FUNCTION: read_msp_pci_counts
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Prints the count of how many times each PCI
 *               interrupt has asserted. Can be invoked by the
 *               /proc filesystem.
 *
 *  INPUTS:      page    - part of STDOUT calculation
 *               off     - part of STDOUT calculation
 *               count   - part of STDOUT calculation
 *               data    - unused
 *
 *  OUTPUTS:     start   - new start location
 *               eof     - end of file pointer
 *
 *  RETURNS:     len     - STDOUT length
 *
 ****************************************************************************/
static int read_msp_pci_counts(char *page, char **start, off_t off,
                int count, int *eof, void *data)
{
    int i;
    int len = 0;
    unsigned int intcount, total = 0;

    for (i = 0; i < 32; ++i) {
        intcount = pci_int_count[i];
        if (intcount != 0) {
            len += sprintf(page + len, "[%d] = %u\n", i, intcount);
            total += intcount;
        }
    }

    len += sprintf(page + len, "total = %u\n", total);
    if (len <= off+count)
        *eof = 1;

    *start = page + off;
    len -= off;
    if (len > count)
        len = count;
    if (len < 0)
        len = 0;

    return len;
}

/*****************************************************************************
 *
 *  FUNCTION: gen_pci_cfg_wr
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Generates a configuration write cycle for debug purposes.
 *               The IDSEL line asserted and location and data written are
 *               immaterial. Just want to be able to prove that a
 *               configuration write can be correctly generated on the
 *               PCI bus.  Intent is that this function by invocable from
 *               the /proc filesystem.
 *
 *  INPUTS:      page    - part of STDOUT calculation
 *               off     - part of STDOUT calculation
 *               count   - part of STDOUT calculation
 *               data    - unused
 *
 *  OUTPUTS:     start   - new start location
 *               eof     - end of file pointer
 *
 *  RETURNS:     len     - STDOUT length
 *
 ****************************************************************************/
static int gen_pci_cfg_wr(char *page, char **start, off_t off,
                int count, int *eof, void *data)
{
    unsigned char where = 0; /* Write to static Device/Vendor ID */
    unsigned char bus_num = 0; /* Bus 0 */
    unsigned char dev_fn = 0xF; /* Arbitrary device number */
    u32 wr_data = 0xFF00AA00; /* Arbitrary data */
    struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
    int len = 0;
    unsigned long value;
    int intr;

    len += sprintf(page + len, "PMC MSP PCI: Beginning\n");

    if (proc_init == 0) {
        pci_proc_init();
        proc_init = ~0;
    }

    len += sprintf(page + len, "PMC MSP PCI: Before Cfg Wr\n");

    /*
     * Generate PCI Configuration Write Cycle
     */

    /* Clear cause register bits */
    preg->if_status = ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F);

    /* Setup address that is to appear on PCI bus */
    preg->config_addr = BPCI_CFGADDR_ENABLE |
        (bus_num << BPCI_CFGADDR_BUSNUM_SHF) |
        (dev_fn << BPCI_CFGADDR_FUNCTNUM_SHF) |
        (where & 0xFC);

    value = cpu_to_le32(wr_data);

    /* Launch the PCI configuration write cycle */
    *PCI_CONFIG_SPACE_REG = value;

    /*
     * Check if the PCI configuration cycle (rd or wr) succeeded, by
     * checking the status bits for errors like master or target abort.
     */
    intr = preg->if_status;

    len += sprintf(page + len, "PMC MSP PCI: After Cfg Wr\n");

    /* Handle STDOUT calculations */
    if (len <= off+count)
        *eof = 1;
    *start = page + off;
    len -= off;
    if (len > count)
        len = count;
    if (len < 0)
        len = 0;

    return len;
}

/*****************************************************************************
 *
 *  FUNCTION: pci_proc_init
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Create entries in the /proc filesystem for debug access.
 *
 *  INPUTS:      none
 *
 *  OUTPUTS:     none
 *
 *  RETURNS:     none
 *
 ****************************************************************************/
static void pci_proc_init(void)
{
    create_proc_read_entry("pmc_msp_pci_rd_cnt", 0, NULL,
                read_msp_pci_counts, NULL);
    create_proc_read_entry("pmc_msp_pci_cfg_wr", 0, NULL,
                gen_pci_cfg_wr, NULL);
}
#endif /* CONFIG_PROC_FS && PCI_COUNTERS */

static DEFINE_SPINLOCK(bpci_lock);

/*****************************************************************************
 *
 *  STRUCT: pci_io_resource
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Defines the address range that pciauto() will use to
 *               assign to the I/O BARs of PCI devices.
 *
 *               Use the start and end addresses of the MSP7120 PCI Host
 *               Controller I/O space, in the form that they appear on the
 *               PCI bus AFTER MSP7120 has performed address translation.
 *
 *               For I/O accesses, MSP7120 ignores OATRAN and maps I/O
 *               accesses into the bottom 0xFFF region of address space,
 *               so that is the range to put into the pci_io_resource
 *               struct.
 *
 *               In MSP4200, the start address was 0x04 instead of the
 *       expected 0x00. Will just assume there was a good reason
 *       for this!
 *
 *  NOTES:       Linux, by default, will assign I/O space to the lowest
 *               region of address space. Since MSP7120 and Linux,
 *               by default, have no offset in between how they map, the
 *               io_offset element of pci_controller struct should be set
 *               to zero.
 *  ELEMENTS:
 *    name       - String used for a meaningful name.
 *
 *    start      - Start address of MSP7120's I/O space, as MSP7120 presents
 *                 the address on the PCI bus.
 *
 *    end        - End address of MSP7120's I/O space, as MSP7120 presents
 *                 the address on the PCI bus.
 *
 *    flags      - Attributes indicating the type of resource. In this case,
 *                 indicate I/O space.
 *
 ****************************************************************************/
static struct resource pci_io_resource = {
    .name   = "pci IO space",
    .start  = 0x04,
    .end    = 0x0FFF,
    .flags  = IORESOURCE_IO /* I/O space */
};

/*****************************************************************************
 *
 *  STRUCT: pci_mem_resource
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Defines the address range that pciauto() will use to
 *               assign to the memory BARs of PCI devices.
 *
 *               The .start and .end values are dependent upon how address
 *               translation is performed by the OATRAN regiser.
 *
 *               The values to use for .start and .end are the values
 *               in the form they appear on the PCI bus AFTER MSP7120 has
 *               performed OATRAN address translation.
 *
 *  ELEMENTS:
 *    name       - String used for a meaningful name.
 *
 *    start      - Start address of MSP7120's memory space, as MSP7120 presents
 *                 the address on the PCI bus.
 *
 *    end        - End address of MSP7120's memory space, as MSP7120 presents
 *                 the address on the PCI bus.
 *
 *    flags      - Attributes indicating the type of resource. In this case,
 *                 indicate memory space.
 *
 ****************************************************************************/
static struct resource pci_mem_resource = {
    .name   = "pci memory space",
    .start  = MSP_PCI_SPACE_BASE,
    .end    = MSP_PCI_SPACE_END,
    .flags  = IORESOURCE_MEM     /* memory space */
};

/*****************************************************************************
 *
 *  FUNCTION: bpci_interrupt
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: PCI status interrupt handler. Updates the count of how
 *               many times each status bit has been set, then clears
 *               the status bits. If the appropriate macros are defined,
 *               these counts can be viewed via the /proc filesystem.
 *
 *  INPUTS:      irq     - unused
 *               dev_id  - unused
 *               pt_regs - unused
 *
 *  OUTPUTS:     none
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
 *
 ****************************************************************************/
static irqreturn_t bpci_interrupt(int irq, void *dev_id)
{
    struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
    unsigned int stat = preg->if_status;

#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
    int i;
    for (i = 0; i < 32; ++i) {
        if ((1 << i) & stat)
            ++pci_int_count[i];
    }
#endif /* PROC_FS && PCI_COUNTERS */

    /* printk("PCI ISR: Status=%08X\n", stat); */

    /* write to clear all asserted interrupts */
    preg->if_status = stat;

    return IRQ_HANDLED;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_config_access
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Performs a PCI configuration access (rd or wr), then
 *               checks that the access succeeded by querying MSP7120's
 *               PCI status bits.
 *
 *  INPUTS:
 *               access_type  - kind of PCI configuration cycle to perform
 *                              (read or write). Legal values are
 *                              PCI_ACCESS_WRITE and PCI_ACCESS_READ.
 *
 *               bus          - pointer to the bus number of the device to
 *                              be targeted for the configuration cycle.
 *                              The only element of the pci_bus structure
 *                              used is bus->number. This argument determines
 *                              if the configuration access will be Type 0 or
 *                              Type 1. Since MSP7120 assumes itself to be the
 *                              PCI Host, any non-zero bus->number generates
 *                              a Type 1 access.
 *
 *               devfn        - this is an 8-bit field. The lower three bits
 *                              specify the function number of the device to
 *                              be targeted for the configuration cycle, with
 *                              all three-bit combinations being legal. The
 *                              upper five bits specify the device number,
 *                              with legal values being 10 to 31.
 *
 *               where        - address within the Configuration Header
 *                              space to access.
 *
 *               data         - for write accesses, contains the data to
 *                              write.
 *
 *  OUTPUTS:
 *               data         - for read accesses, contains the value read.
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
 *               -1                  - access failure
 *
 ****************************************************************************/
int msp_pcibios_config_access(unsigned char access_type,
                struct pci_bus *bus,
                unsigned int devfn,
                unsigned char where,
                u32 *data)
{
    struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
    unsigned char bus_num = bus->number;
    unsigned char dev_fn = (unsigned char)devfn;
    unsigned long flags;
    unsigned long intr;
    unsigned long value;
    static char pciirqflag;
    int ret;
#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
    unsigned int    vpe_status;
#endif

#if defined(CONFIG_PROC_FS) && defined(PCI_COUNTERS)
    if (proc_init == 0) {
        pci_proc_init();
        proc_init = ~0;
    }
#endif /* CONFIG_PROC_FS && PCI_COUNTERS */

    /*
     * Just the first time this function invokes, allocate
     * an interrupt line for PCI host status interrupts. The
     * allocation assigns an interrupt handler to the interrupt.
     */
    if (pciirqflag == 0) {
        ret = request_irq(MSP_INT_PCI,/* Hardcoded internal MSP7120 wiring */
                bpci_interrupt,
                IRQF_SHARED,
                "PMC MSP PCI Host",
                preg);
        if (ret != 0)
            return ret;
        pciirqflag = ~0;
    }

#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
    local_irq_save(flags);
    vpe_status = dvpe();
#else
    spin_lock_irqsave(&bpci_lock, flags);
#endif

    /*
     * Clear PCI cause register bits.
     *
     * In Polo, the PCI Host had a dedicated DMA called the
     * Block Copy (not to be confused with the general purpose Block
     * Copy Engine block). There appear to have been special interrupts
     * for this Block Copy, called Block Copy 0 Fault (BC0F) and
     * Block Copy 1 Fault (BC1F). MSP4200 and MSP7120 don't have this
     * dedicated Block Copy block, so these two interrupts are now
     * marked reserved. In case the  Block Copy is resurrected in a
     * future design, maintain the code that treats these two interrupts
     * specially.
     *
     * Write to clear all interrupts in the PCI status register, aside
     * from BC0F and BC1F.
     */
    preg->if_status = ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F);

    /* Setup address that is to appear on PCI bus */
    preg->config_addr = BPCI_CFGADDR_ENABLE |
        (bus_num << BPCI_CFGADDR_BUSNUM_SHF) |
        (dev_fn << BPCI_CFGADDR_FUNCTNUM_SHF) |
        (where & 0xFC);

    /* IF access is a PCI configuration write */
    if (access_type == PCI_ACCESS_WRITE) {
        value = cpu_to_le32(*data);
        *PCI_CONFIG_SPACE_REG = value;
    } else {
        /* ELSE access is a PCI configuration read */
        value = le32_to_cpu(*PCI_CONFIG_SPACE_REG);
        *data = value;
    }

    /*
     * Check if the PCI configuration cycle (rd or wr) succeeded, by
     * checking the status bits for errors like master or target abort.
     */
    intr = preg->if_status;

    /* Clear config access */
    preg->config_addr = 0;

    /* IF error occurred */
    if (intr & ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F)) {
        /* Clear status bits */
        preg->if_status = ~(BPCI_IFSTATUS_BC0F | BPCI_IFSTATUS_BC1F);

#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
        evpe(vpe_status);
        local_irq_restore(flags);
#else
        spin_unlock_irqrestore(&bpci_lock, flags);
#endif

        return -1;
    }

#if defined(CONFIG_PMC_MSP7120_GW) || defined(CONFIG_PMC_MSP7120_EVAL)
    evpe(vpe_status);
    local_irq_restore(flags);
#else
    spin_unlock_irqrestore(&bpci_lock, flags);
#endif

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_read_config_byte
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Read a byte from PCI configuration address spac
 *               Since the hardware can't address 8 bit chunks
 *               directly, read a 32-bit chunk, then mask off extraneous
 *               bits.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the read is destined for.
 *               devfn  - device/function combination that the read is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *
 *  OUTPUTS      val    - read data
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
 *               -1                  - read access failure
 *
 ****************************************************************************/
static int
msp_pcibios_read_config_byte(struct pci_bus *bus,
                unsigned int devfn,
                int where,
                u32 *val)
{
    u32 data = 0;

    /*
     * If the config access did not complete normally (e.g., underwent
     * master abort) do the PCI compliant thing, which is to supply an
     * all ones value.
     */
    if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
                    where, &data)) {
        *val = 0xFFFFFFFF;
        return -1;
    }

    *val = (data >> ((where & 3) << 3)) & 0x0ff;

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_read_config_word
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Read a word (16 bits) from PCI configuration address space.
 *               Since the hardware can't address 16 bit chunks
 *               directly, read a 32-bit chunk, then mask off extraneous
 *               bits.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the read is destined for.
 *               devfn  - device/function combination that the read is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *
 *  OUTPUTS      val    - read data
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
 *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
 *               -1                           - read access failure
 *
 ****************************************************************************/
static int
msp_pcibios_read_config_word(struct pci_bus *bus,
                unsigned int devfn,
                int where,
                u32 *val)
{
    u32 data = 0;

    /* if (where & 1) */    /* Commented out non-compliant code.
                 * Should allow word access to configuration
                 * registers, with only exception being when
                 * the word access would wrap around into
                 * the next dword.
                 */
    if ((where & 3) == 3) {
        *val = 0xFFFFFFFF;
        return PCIBIOS_BAD_REGISTER_NUMBER;
    }

    /*
     * If the config access did not complete normally (e.g., underwent
     * master abort) do the PCI compliant thing, which is to supply an
     * all ones value.
     */
    if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
                    where, &data)) {
        *val = 0xFFFFFFFF;
        return -1;
    }

    *val = (data >> ((where & 3) << 3)) & 0x0ffff;

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_read_config_dword
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Read a double word (32 bits) from PCI configuration
 *               address space.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the read is destined for.
 *               devfn  - device/function combination that the read is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *
 *  OUTPUTS      val    - read data
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
 *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
 *               -1                           - read access failure
 *
 ****************************************************************************/
static int
msp_pcibios_read_config_dword(struct pci_bus *bus,
                unsigned int devfn,
                int where,
                u32 *val)
{
    u32 data = 0;

    /* Address must be dword aligned. */
    if (where & 3) {
        *val = 0xFFFFFFFF;
        return PCIBIOS_BAD_REGISTER_NUMBER;
    }

    /*
     * If the config access did not complete normally (e.g., underwent
     * master abort) do the PCI compliant thing, which is to supply an
     * all ones value.
     */
    if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
                    where, &data)) {
        *val = 0xFFFFFFFF;
        return -1;
    }

    *val = data;

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_write_config_byte
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Write a byte to PCI configuration address space.
 *               Since the hardware can't address 8 bit chunks
 *               directly, a read-modify-write is performed.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the write is destined for.
 *               devfn  - device/function combination that the write is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *               val    - value to write
 *
 *  OUTPUTS      none
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL  - success
 *               -1                  - write access failure
 *
 ****************************************************************************/
static int
msp_pcibios_write_config_byte(struct pci_bus *bus,
                unsigned int devfn,
                int where,
                u8 val)
{
    u32 data = 0;

    /* read config space */
    if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
                    where, &data))
        return -1;

    /* modify the byte within the dword */
    data = (data & ~(0xff << ((where & 3) << 3))) |
            (val << ((where & 3) << 3));

    /* write back the full dword */
    if (msp_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn,
                    where, &data))
        return -1;

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_write_config_word
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Write a word (16-bits) to PCI configuration address space.
 *               Since the hardware can't address 16 bit chunks
 *               directly, a read-modify-write is performed.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the write is destined for.
 *               devfn  - device/function combination that the write is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *               val    - value to write
 *
 *  OUTPUTS      none
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
 *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
 *               -1                           - write access failure
 *
 ****************************************************************************/
static int
msp_pcibios_write_config_word(struct pci_bus *bus,
                unsigned int devfn,
                int where,
                u16 val)
{
    u32 data = 0;

    /* Fixed non-compliance: if (where & 1) */
    if ((where & 3) == 3)
        return PCIBIOS_BAD_REGISTER_NUMBER;

    /* read config space */
    if (msp_pcibios_config_access(PCI_ACCESS_READ, bus, devfn,
                    where, &data))
        return -1;

    /* modify the word within the dword */
    data = (data & ~(0xffff << ((where & 3) << 3))) |
            (val << ((where & 3) << 3));

    /* write back the full dword */
    if (msp_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn,
                    where, &data))
        return -1;

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_write_config_dword
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Write a double word (32-bits) to PCI configuration address
 *               space.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the write is destined for.
 *               devfn  - device/function combination that the write is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *               val    - value to write
 *
 *  OUTPUTS      none
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL           - success
 *               PCIBIOS_BAD_REGISTER_NUMBER  - bad register address
 *               -1                           - write access failure
 *
 ****************************************************************************/
static int
msp_pcibios_write_config_dword(struct pci_bus *bus,
                unsigned int devfn,
                int where,
                u32 val)
{
    /* check that address is dword aligned */
    if (where & 3)
        return PCIBIOS_BAD_REGISTER_NUMBER;

    /* perform write */
    if (msp_pcibios_config_access(PCI_ACCESS_WRITE, bus, devfn,
                    where, &val))
        return -1;

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_read_config
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Interface the PCI configuration read request with
 *               the appropriate function, based on how many bytes
 *               the read request is.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the write is destined for.
 *               devfn  - device/function combination that the write is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *               size   - in units of bytes, should be 1, 2, or 4.
 *
 *  OUTPUTS      val    - value read, with any extraneous bytes masked
 *                        to zero.
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL   - success
 *               -1                   - failure
 *
 ****************************************************************************/
int
msp_pcibios_read_config(struct pci_bus *bus,
            unsigned int    devfn,
            int where,
            int size,
            u32 *val)
{
    if (size == 1) {
        if (msp_pcibios_read_config_byte(bus, devfn, where, val)) {
            return -1;
        }
    } else if (size == 2) {
        if (msp_pcibios_read_config_word(bus, devfn, where, val)) {
            return -1;
        }
    } else if (size == 4) {
        if (msp_pcibios_read_config_dword(bus, devfn, where, val)) {
            return -1;
        }
    } else {
        *val = 0xFFFFFFFF;
        return -1;
    }

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  FUNCTION: msp_pcibios_write_config
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Interface the PCI configuration write request with
 *               the appropriate function, based on how many bytes
 *               the read request is.
 *
 *  INPUTS       bus    - structure containing attributes for the PCI bus
 *                        that the write is destined for.
 *               devfn  - device/function combination that the write is
 *                        destined for.
 *               where  - register within the Configuration Header space
 *                        to access.
 *               size   - in units of bytes, should be 1, 2, or 4.
 *               val    - value to write
 *
 *  OUTPUTS:     none
 *
 *  RETURNS:     PCIBIOS_SUCCESSFUL   - success
 *               -1                   - failure
 *
 ****************************************************************************/
int
msp_pcibios_write_config(struct pci_bus *bus,
            unsigned int devfn,
            int where,
            int size,
            u32 val)
{
    if (size == 1) {
        if (msp_pcibios_write_config_byte(bus, devfn,
                        where, (u8)(0xFF & val))) {
            return -1;
        }
    } else if (size == 2) {
        if (msp_pcibios_write_config_word(bus, devfn,
                        where, (u16)(0xFFFF & val))) {
            return -1;
        }
    } else if (size == 4) {
        if (msp_pcibios_write_config_dword(bus, devfn, where, val)) {
            return -1;
        }
    } else {
        return -1;
    }

    return PCIBIOS_SUCCESSFUL;
}

/*****************************************************************************
 *
 *  STRUCTURE: msp_pci_ops
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: structure to abstract the hardware specific PCI
 *               configuration accesses.
 *
 *  ELEMENTS:
 *    read      - function for Linux to generate PCI Configuration reads.
 *    write     - function for Linux to generate PCI Configuration writes.
 *
 ****************************************************************************/
struct pci_ops msp_pci_ops = {
    .read = msp_pcibios_read_config,
    .write = msp_pcibios_write_config
};

/*****************************************************************************
 *
 *  STRUCTURE: msp_pci_controller
 *  _________________________________________________________________________
 *
 *  Describes the attributes of the MSP7120 PCI Host Controller
 *
 *  ELEMENTS:
 *    pci_ops      - abstracts the hardware specific PCI configuration
 *                   accesses.
 *
 *    mem_resource - address range pciauto() uses to assign to PCI device
 *                   memory BARs.
 *
 *    mem_offset   - offset between how MSP7120 outbound PCI memory
 *                   transaction addresses appear on the PCI bus and how Linux
 *                   wants to configure memory BARs of the PCI devices.
 *                   MSP7120 does nothing funky, so just set to zero.
 *
 *    io_resource  - address range pciauto() uses to assign to PCI device
 *                   I/O BARs.
 *
 *    io_offset    - offset between how MSP7120 outbound PCI I/O
 *                   transaction addresses appear on the PCI bus and how
 *                   Linux defaults to configure I/O BARs of the PCI devices.
 *                   MSP7120 maps outbound I/O accesses into the bottom
 *                   bottom 4K of PCI address space (and ignores OATRAN).
 *                   Since the Linux default is to configure I/O BARs to the
 *                   bottom 4K, no special offset is needed. Just set to zero.
 *
 ****************************************************************************/
static struct pci_controller msp_pci_controller = {
    .pci_ops    = &msp_pci_ops,
    .mem_resource   = &pci_mem_resource,
    .mem_offset = 0,
    .io_map_base    = MSP_PCI_IOSPACE_BASE,
    .io_resource    = &pci_io_resource,
    .io_offset  = 0
};

/*****************************************************************************
 *
 *  FUNCTION: msp_pci_init
 *  _________________________________________________________________________
 *
 *  DESCRIPTION: Initialize the PCI Host Controller and register it with
 *               Linux so Linux can seize control of the PCI bus.
 *
 ****************************************************************************/
void __init msp_pci_init(void)
{
    struct msp_pci_regs *preg = (void *)PCI_BASE_REG;
    u32 id;

    /* Extract Device ID */
    id = read_reg32(PCI_JTAG_DEVID_REG, 0xFFFF) >> 12;

    /* Check if JTAG ID identifies MSP7120 */
    if (!MSP_HAS_PCI(id)) {
        printk(KERN_WARNING "PCI: No PCI; id reads as %x\n", id);
        goto no_pci;
    }

    /*
     * Enable flushing of the PCI-SDRAM queue upon a read
     * of the SDRAM's Memory Configuration Register.
     */
    *(unsigned long *)QFLUSH_REG_1 = 3;

    /* Configure PCI Host Controller. */
    preg->if_status = ~0;       /* Clear cause register bits */
    preg->config_addr = 0;      /* Clear config access */
    preg->oatran    = MSP_PCI_OATRAN; /* PCI outbound addr translation */
    preg->if_mask   = 0xF8BF87C0;   /* Enable all PCI status interrupts */

    /* configure so inb(), outb(), and family are functional */
    set_io_port_base(MSP_PCI_IOSPACE_BASE);

    /* Tell Linux the details of the MSP7120 PCI Host Controller */
    register_pci_controller(&msp_pci_controller);

    return;

no_pci:
    /* Disable PCI channel */
    printk(KERN_WARNING "PCI: no host PCI bus detected\n");
}