common/os/sunpci.c

	sunpci.c revision 2df1fe9ca32bb227b9158c67f5c00b54c20b10fd
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <sys/sunndi.h>
#include <sys/sysmacros.h>
#include <sys/pci.h>
#include <sys/pcie.h>
#include <sys/pci_impl.h>
#include <sys/epm.h>

int
pci_config_setup(dev_info_t *dip, ddi_acc_handle_t *handle)
{
    caddr_t cfgaddr;
    ddi_device_acc_attr_t attr;

    attr.devacc_attr_version = DDI_DEVICE_ATTR_V0;
    attr.devacc_attr_endian_flags = DDI_STRUCTURE_LE_ACC;
    attr.devacc_attr_dataorder = DDI_STRICTORDER_ACC;

    /* Check for fault management capabilities */
    if (DDI_FM_ACC_ERR_CAP(ddi_fm_capable(dip))) {
        attr.devacc_attr_version = DDI_DEVICE_ATTR_V1;
        attr.devacc_attr_access = DDI_FLAGERR_ACC;
    }

    return (ddi_regs_map_setup(dip, 0, &cfgaddr, 0, 0, &attr, handle));
}

void
pci_config_teardown(ddi_acc_handle_t *handle)
{
    ddi_regs_map_free(handle);
}

uint8_t
pci_config_get8(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get8(handle, (uint8_t *)cfgaddr));
}

uint16_t
pci_config_get16(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get16(handle, (uint16_t *)cfgaddr));
}

uint32_t
pci_config_get32(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get32(handle, (uint32_t *)cfgaddr));
}

uint64_t
pci_config_get64(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get64(handle, (uint64_t *)cfgaddr));
}

void
pci_config_put8(ddi_acc_handle_t handle, off_t offset, uint8_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put8(handle, (uint8_t *)cfgaddr, value);
}

void
pci_config_put16(ddi_acc_handle_t handle, off_t offset, uint16_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put16(handle, (uint16_t *)cfgaddr, value);
}

void
pci_config_put32(ddi_acc_handle_t handle, off_t offset, uint32_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put32(handle, (uint32_t *)cfgaddr, value);
}

void
pci_config_put64(ddi_acc_handle_t handle, off_t offset, uint64_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put64(handle, (uint64_t *)cfgaddr, value);
}

/*
 * We need to separate the old interfaces from the new ones and leave them
 * in here for a while. Previous versions of the OS defined the new interfaces
 * to the old interfaces. This way we can fix things up so that we can
 * eventually remove these interfaces.
 * e.g. A 3rd party module/driver using pci_config_get8 and built against S10
 * or earlier will actually have a reference to pci_config_getb in the binary.
 */
#ifdef _ILP32
uint8_t
pci_config_getb(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get8(handle, (uint8_t *)cfgaddr));
}

uint16_t
pci_config_getw(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get16(handle, (uint16_t *)cfgaddr));
}

uint32_t
pci_config_getl(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get32(handle, (uint32_t *)cfgaddr));
}

uint64_t
pci_config_getll(ddi_acc_handle_t handle, off_t offset)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    return (ddi_get64(handle, (uint64_t *)cfgaddr));
}

void
pci_config_putb(ddi_acc_handle_t handle, off_t offset, uint8_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put8(handle, (uint8_t *)cfgaddr, value);
}

void
pci_config_putw(ddi_acc_handle_t handle, off_t offset, uint16_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put16(handle, (uint16_t *)cfgaddr, value);
}

void
pci_config_putl(ddi_acc_handle_t handle, off_t offset, uint32_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put32(handle, (uint32_t *)cfgaddr, value);
}

void
pci_config_putll(ddi_acc_handle_t handle, off_t offset, uint64_t value)
{
    caddr_t cfgaddr;
    ddi_acc_hdl_t *hp;

    hp = impl_acc_hdl_get(handle);
    cfgaddr = hp->ah_addr + offset;
    ddi_put64(handle, (uint64_t *)cfgaddr, value);
}
#endif /* _ILP32 */

/*ARGSUSED*/
int
pci_report_pmcap(dev_info_t *dip, int cap, void *arg)
{
    return (DDI_SUCCESS);
}

/*
 * Note about saving and restoring config space.
 * PCI devices have only upto 256 bytes of config space while PCI Express
 * devices can have upto 4k config space. In case of PCI Express device,
 * we save all 4k config space and restore it even if it doesn't make use
 * of all 4k. But some devices don't respond to reads to non-existent
 * registers within the config space. To avoid any panics, we use ddi_peek
 * to do the reads. A bit mask is used to indicate which words of the
 * config space are accessible. While restoring the config space, only those
 * readable words are restored. We do all this in 32 bit size words.
 */
#define INDEX_SHIFT     3
#define BITMASK         0x7

static uint32_t pci_save_caps(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    pci_cap_save_desc_t *cap_descp, uint32_t *ncapsp);
static void pci_restore_caps(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    pci_cap_save_desc_t *cap_descp, uint32_t elements);
static uint32_t pci_generic_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr,
    uint32_t *regbuf, uint32_t nwords);
static uint32_t pci_msi_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr,
    uint32_t *regbuf, uint32_t notused);
static uint32_t pci_pcix_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr,
    uint32_t *regbuf, uint32_t notused);
static uint32_t pci_pcie_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr,
    uint32_t *regbuf, uint32_t notused);
static void pci_fill_buf(ddi_acc_handle_t confhdl, uint16_t cap_ptr,
    uint32_t *regbuf, uint32_t nwords);
static uint32_t cap_walk_and_save(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    pci_cap_save_desc_t *cap_descp, uint32_t *ncapsp, int xspace);
static void pci_pmcap_check(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    uint16_t pmcap_offset);

/*
 * Table below specifies the number of registers to be saved for each PCI
 * capability. pci_generic_save saves the number of words specified in the
 * table. Any special considerations will be taken care by the capability
 * specific save function e.g. use pci_msi_save to save registers associated
 * with MSI capability. PCI_UNKNOWN_SIZE indicates that number of registers
 * to be saved is variable and will be determined by the specific save function.
 * Currently we save/restore all the registers associated with the capability
 * including read only registers. Regsiters are saved and restored in 32 bit
 * size words.
 */
static pci_cap_entry_t pci_cap_table[] = {
    {PCI_CAP_ID_PM, PCI_PMCAP_NDWORDS, pci_generic_save},
    {PCI_CAP_ID_AGP, PCI_AGP_NDWORDS, pci_generic_save},
    {PCI_CAP_ID_SLOT_ID, PCI_SLOTID_NDWORDS, pci_generic_save},
    {PCI_CAP_ID_MSI_X, PCI_MSIX_NDWORDS, pci_generic_save},
    {PCI_CAP_ID_MSI, PCI_CAP_SZUNKNOWN, pci_msi_save},
    {PCI_CAP_ID_PCIX, PCI_CAP_SZUNKNOWN, pci_pcix_save},
    {PCI_CAP_ID_PCI_E, PCI_CAP_SZUNKNOWN, pci_pcie_save},
    /*
     * {PCI_CAP_ID_cPCI_CRC, 0, NULL},
     * {PCI_CAP_ID_VPD, 0, NULL},
     * {PCI_CAP_ID_cPCI_HS, 0, NULL},
     * {PCI_CAP_ID_PCI_HOTPLUG, 0, NULL},
     * {PCI_CAP_ID_AGP_8X, 0, NULL},
     * {PCI_CAP_ID_SECURE_DEV, 0, NULL},
     */
    {PCI_CAP_NEXT_PTR_NULL, 0, NULL}
};

/*
 * Save the configuration registers for cdip as a property
 * so that it persists after detach/uninitchild.
 */
int
pci_save_config_regs(dev_info_t *dip)
{
    ddi_acc_handle_t confhdl;
    pci_config_header_state_t *chsp;
    pci_cap_save_desc_t *pci_cap_descp;
    int ret;
    uint32_t i, ncaps, nwords;
    uint32_t *regbuf, *p;
    uint8_t *maskbuf;
    size_t maskbufsz, regbufsz, capbufsz;
    ddi_acc_hdl_t *hp;
    off_t offset = 0;
    uint8_t cap_ptr, cap_id;
    int pcie = 0;
    PMD(PMD_SX, ("pci_save_config_regs %s:%d\n", ddi_driver_name(dip),
        ddi_get_instance(dip)))

    if (pci_config_setup(dip, &confhdl) != DDI_SUCCESS) {
        cmn_err(CE_WARN, "%s%d can't get config handle",
            ddi_driver_name(dip), ddi_get_instance(dip));

        return (DDI_FAILURE);
    }
    /*
     * Determine if it is a pci express device. If it is, save entire
     * 4k config space treating it as a array of 32 bit integers.
     * If it is not, do it in a usual PCI way.
     */
    cap_ptr = pci_config_get8(confhdl, PCI_BCNF_CAP_PTR);
    /*
     * Walk the capabilities searching for pci express capability
     */
    while (cap_ptr != PCI_CAP_NEXT_PTR_NULL) {
        cap_id = pci_config_get8(confhdl,
            cap_ptr + PCI_CAP_ID);
        if (cap_id == PCI_CAP_ID_PCI_E) {
            pcie = 1;
            break;
        }
        cap_ptr = pci_config_get8(confhdl,
            cap_ptr + PCI_CAP_NEXT_PTR);
    }

    if (pcie) {
        /* PCI express device. Can have data in all 4k space */
        regbuf = (uint32_t *)kmem_zalloc((size_t)PCIE_CONF_HDR_SIZE,
            KM_SLEEP);
        p = regbuf;
        /*
         * Allocate space for mask.
         * mask size is 128 bytes (4096 / 4 / 8 )
         */
        maskbufsz = (size_t)((PCIE_CONF_HDR_SIZE/ sizeof (uint32_t)) >>
            INDEX_SHIFT);
        maskbuf = (uint8_t *)kmem_zalloc(maskbufsz, KM_SLEEP);
        hp = impl_acc_hdl_get(confhdl);
        for (i = 0; i < (PCIE_CONF_HDR_SIZE / sizeof (uint32_t)); i++) {
            if (ddi_peek32(dip, (int32_t *)(hp->ah_addr + offset),
                (int32_t *)p) == DDI_SUCCESS) {
                /* it is readable register. set the bit */
                maskbuf[i >> INDEX_SHIFT] |=
                    (uint8_t)(1 << (i & BITMASK));
            }
            p++;
            offset += sizeof (uint32_t);
        }

        if ((ret = ndi_prop_update_byte_array(DDI_DEV_T_NONE, dip,
            SAVED_CONFIG_REGS_MASK, (uchar_t *)maskbuf,
            maskbufsz)) != DDI_PROP_SUCCESS) {
            cmn_err(CE_WARN, "couldn't create %s property while"
                "saving config space for %s@%d\n",
                SAVED_CONFIG_REGS_MASK, ddi_driver_name(dip),
                ddi_get_instance(dip));
        } else if ((ret = ndi_prop_update_byte_array(DDI_DEV_T_NONE,
            dip, SAVED_CONFIG_REGS, (uchar_t *)regbuf,
            (size_t)PCIE_CONF_HDR_SIZE)) != DDI_PROP_SUCCESS) {
            (void) ddi_prop_remove(DDI_DEV_T_NONE, dip,
                SAVED_CONFIG_REGS_MASK);
            cmn_err(CE_WARN, "%s%d can't update prop %s",
                ddi_driver_name(dip), ddi_get_instance(dip),
                SAVED_CONFIG_REGS);
        }

        kmem_free(maskbuf, (size_t)maskbufsz);
        kmem_free(regbuf, (size_t)PCIE_CONF_HDR_SIZE);
    } else {
        regbuf = (uint32_t *)kmem_zalloc((size_t)PCI_CONF_HDR_SIZE,
            KM_SLEEP);
        chsp = (pci_config_header_state_t *)regbuf;

        chsp->chs_command = pci_config_get16(confhdl, PCI_CONF_COMM);
        chsp->chs_header_type = pci_config_get8(confhdl,
            PCI_CONF_HEADER);
        if ((chsp->chs_header_type & PCI_HEADER_TYPE_M) ==
            PCI_HEADER_ONE)
            chsp->chs_bridge_control =
                pci_config_get16(confhdl, PCI_BCNF_BCNTRL);
        chsp->chs_cache_line_size = pci_config_get8(confhdl,
            PCI_CONF_CACHE_LINESZ);
        chsp->chs_latency_timer = pci_config_get8(confhdl,
            PCI_CONF_LATENCY_TIMER);
        if ((chsp->chs_header_type & PCI_HEADER_TYPE_M) ==
            PCI_HEADER_ONE) {
            chsp->chs_sec_latency_timer =
                pci_config_get8(confhdl, PCI_BCNF_LATENCY_TIMER);
        }

        chsp->chs_base0 = pci_config_get32(confhdl, PCI_CONF_BASE0);
        chsp->chs_base1 = pci_config_get32(confhdl, PCI_CONF_BASE1);
        chsp->chs_base2 = pci_config_get32(confhdl, PCI_CONF_BASE2);
        chsp->chs_base3 = pci_config_get32(confhdl, PCI_CONF_BASE3);
        chsp->chs_base4 = pci_config_get32(confhdl, PCI_CONF_BASE4);
        chsp->chs_base5 = pci_config_get32(confhdl, PCI_CONF_BASE5);

        /*
         * Allocate maximum space required for capability descriptions.
         * The maximum number of capabilties saved is the number of
         * capabilities listed in the pci_cap_table.
         */
        ncaps = (sizeof (pci_cap_table) / sizeof (pci_cap_entry_t));
        capbufsz = ncaps * sizeof (pci_cap_save_desc_t);
        pci_cap_descp = (pci_cap_save_desc_t *)kmem_zalloc(
            capbufsz, KM_SLEEP);
        p = (uint32_t *)((caddr_t)regbuf +
            sizeof (pci_config_header_state_t));
        nwords = pci_save_caps(confhdl, p, pci_cap_descp, &ncaps);
        regbufsz = sizeof (pci_config_header_state_t) +
            nwords * sizeof (uint32_t);

        if ((ret = ndi_prop_update_byte_array(DDI_DEV_T_NONE, dip,
            SAVED_CONFIG_REGS, (uchar_t *)regbuf, regbufsz)) !=
            DDI_PROP_SUCCESS) {
            cmn_err(CE_WARN, "%s%d can't update prop %s",
                ddi_driver_name(dip), ddi_get_instance(dip),
                SAVED_CONFIG_REGS);
        } else if (ncaps) {
            ret = ndi_prop_update_byte_array(DDI_DEV_T_NONE, dip,
                SAVED_CONFIG_REGS_CAPINFO, (uchar_t *)pci_cap_descp,
                ncaps * sizeof (pci_cap_save_desc_t));
            if (ret != DDI_PROP_SUCCESS)
                (void) ddi_prop_remove(DDI_DEV_T_NONE, dip,
                    SAVED_CONFIG_REGS);
        }
        kmem_free(regbuf, (size_t)PCI_CONF_HDR_SIZE);
        kmem_free(pci_cap_descp, capbufsz);
    }
    pci_config_teardown(&confhdl);

    if (ret != DDI_PROP_SUCCESS)
        return (DDI_FAILURE);

    return (DDI_SUCCESS);
}

/*
 * Saves registers associated with PCI capabilities.
 * Returns number of 32 bit words saved.
 * Number of capabilities saved is returned in ncapsp.
 */
static uint32_t
pci_save_caps(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    pci_cap_save_desc_t *cap_descp, uint32_t *ncapsp)
{
    return (cap_walk_and_save(confhdl, regbuf, cap_descp, ncapsp, 0));
}

static uint32_t
cap_walk_and_save(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    pci_cap_save_desc_t *cap_descp, uint32_t *ncapsp, int xspace)
{
    pci_cap_entry_t *pci_cap_entp;
    uint16_t cap_id, offset;
    uint32_t words_saved = 0, nwords = 0;
    uint16_t cap_ptr = PCI_CAP_NEXT_PTR_NULL;

    *ncapsp = 0;
    if (!xspace)
        cap_ptr = pci_config_get8(confhdl, PCI_BCNF_CAP_PTR);
    /*
     * Walk the capabilities
     */
    while (cap_ptr != PCI_CAP_NEXT_PTR_NULL) {
        cap_id = CAP_ID(confhdl, cap_ptr, xspace);
        /* Search for this cap id in our table */
        if (!xspace)
            pci_cap_entp = pci_cap_table;
        while (pci_cap_entp->cap_id != PCI_CAP_NEXT_PTR_NULL &&
            pci_cap_entp->cap_id != cap_id)
            pci_cap_entp++;

        offset = cap_ptr;
        cap_ptr = NEXT_CAP(confhdl, cap_ptr, xspace);
        /*
         * If this cap id is not found in the table, there is nothing
         * to save.
         */
        if (pci_cap_entp->cap_id == PCI_CAP_NEXT_PTR_NULL)
            continue;
        if (pci_cap_entp->cap_save_func) {
            if ((nwords = pci_cap_entp->cap_save_func(confhdl,
                offset, regbuf, pci_cap_entp->cap_ndwords))) {
                cap_descp->cap_nregs = nwords;
                cap_descp->cap_offset = offset;
                cap_descp->cap_id = cap_id;
                regbuf += nwords;
                cap_descp++;
                words_saved += nwords;
                (*ncapsp)++;
            }
        }

    }
    return (words_saved);
}

static void
pci_fill_buf(ddi_acc_handle_t confhdl, uint16_t cap_ptr,
    uint32_t *regbuf, uint32_t nwords)
{
    int i;

    for (i = 0; i < nwords; i++) {
        *regbuf = pci_config_get32(confhdl, cap_ptr);
        regbuf++;
        cap_ptr += 4;
    }
}

static uint32_t
pci_generic_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr, uint32_t *regbuf,
    uint32_t nwords)
{
    pci_fill_buf(confhdl, cap_ptr, regbuf, nwords);
    return (nwords);
}

/*ARGSUSED*/
static uint32_t
pci_msi_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr, uint32_t *regbuf,
    uint32_t notused)
{
    uint32_t nwords = PCI_MSI_MIN_WORDS;
    uint16_t msi_ctrl;

    /* Figure out how many registers to be saved */
    msi_ctrl = pci_config_get16(confhdl, cap_ptr + PCI_MSI_CTRL);
    /* If 64 bit address capable add one word */
    if (msi_ctrl & PCI_MSI_64BIT_MASK)
        nwords++;
    /* If per vector masking capable, add two more words */
    if (msi_ctrl & PCI_MSI_PVM_MASK)
        nwords += 2;
    pci_fill_buf(confhdl, cap_ptr, regbuf, nwords);

    return (nwords);
}

/*ARGSUSED*/
static uint32_t
pci_pcix_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr, uint32_t *regbuf,
    uint32_t notused)
{
    uint32_t nwords = PCI_PCIX_MIN_WORDS;
    uint16_t pcix_command;

    /* Figure out how many registers to be saved */
    pcix_command = pci_config_get16(confhdl, cap_ptr + PCI_PCIX_COMMAND);
    /* If it is version 1 or version 2, add 4 words */
    if (((pcix_command & PCI_PCIX_VER_MASK) == PCI_PCIX_VER_1) ||
        ((pcix_command & PCI_PCIX_VER_MASK) == PCI_PCIX_VER_2))
        nwords += 4;
    pci_fill_buf(confhdl, cap_ptr, regbuf, nwords);

    return (nwords);
}

/*ARGSUSED*/
static uint32_t
pci_pcie_save(ddi_acc_handle_t confhdl, uint16_t cap_ptr, uint32_t *regbuf,
    uint32_t notused)
{
    return (0);
}

static void
pci_pmcap_check(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    uint16_t pmcap_offset)
{
    uint16_t pmcsr;
    uint16_t pmcsr_offset = pmcap_offset + PCI_PMCSR;
    uint32_t *saved_pmcsrp = (uint32_t *)((caddr_t)regbuf + PCI_PMCSR);

    /*
     * Copy the power state bits from the PMCSR to our saved copy.
     * This is to make sure that we don't change the D state when
     * we restore config space of the device.
     */
    pmcsr = pci_config_get16(confhdl, pmcsr_offset);
    (*saved_pmcsrp) &= ~PCI_PMCSR_STATE_MASK;
    (*saved_pmcsrp) |= (pmcsr & PCI_PMCSR_STATE_MASK);
}

static void
pci_restore_caps(ddi_acc_handle_t confhdl, uint32_t *regbuf,
    pci_cap_save_desc_t *cap_descp, uint32_t elements)
{
    int i, j;
    uint16_t offset;

    for (i = 0; i < (elements / sizeof (pci_cap_save_desc_t)); i++) {
        offset = cap_descp->cap_offset;
        if (cap_descp->cap_id == PCI_CAP_ID_PM)
            pci_pmcap_check(confhdl, regbuf, offset);
        for (j = 0; j < cap_descp->cap_nregs; j++) {
            pci_config_put32(confhdl, offset, *regbuf);
            regbuf++;
            offset += 4;
        }
        cap_descp++;
    }
}

/*
 * Restore config_regs from a single devinfo node.
 */
int
pci_restore_config_regs(dev_info_t *dip)
{
    ddi_acc_handle_t confhdl;
    pci_config_header_state_t *chs_p;
    pci_cap_save_desc_t *cap_descp;
    uint32_t elements, i;
    uint8_t *maskbuf;
    uint32_t *regbuf, *p;
    off_t offset = 0;

    if (pci_config_setup(dip, &confhdl) != DDI_SUCCESS) {
        cmn_err(CE_WARN, "%s%d can't get config handle",
            ddi_driver_name(dip), ddi_get_instance(dip));
        return (DDI_FAILURE);
    }

    if (ddi_prop_lookup_byte_array(DDI_DEV_T_ANY, dip,
        DDI_PROP_DONTPASS | DDI_PROP_NOTPROM, SAVED_CONFIG_REGS_MASK,
        (uchar_t **)&maskbuf, &elements) == DDI_PROP_SUCCESS) {

        if (ddi_prop_lookup_byte_array(DDI_DEV_T_ANY, dip,
            DDI_PROP_DONTPASS | DDI_PROP_NOTPROM, SAVED_CONFIG_REGS,
            (uchar_t **)&regbuf, &elements) != DDI_PROP_SUCCESS) {
            goto restoreconfig_err;
        }
        ASSERT(elements == PCIE_CONF_HDR_SIZE);
        /* pcie device and has 4k config space saved */
        p = regbuf;
        for (i = 0; i < PCIE_CONF_HDR_SIZE / sizeof (uint32_t); i++) {
            /* If the word is readable then restore it */
            if (maskbuf[i >> INDEX_SHIFT] &
                (uint8_t)(1 << (i & BITMASK)))
                pci_config_put32(confhdl, offset, *p);
            p++;
            offset += sizeof (uint32_t);
        }
        ddi_prop_free(regbuf);
        ddi_prop_free(maskbuf);
        if (ndi_prop_remove(DDI_DEV_T_NONE, dip,
            SAVED_CONFIG_REGS_MASK) != DDI_PROP_SUCCESS) {
            cmn_err(CE_WARN, "%s%d can't remove prop %s",
                ddi_driver_name(dip), ddi_get_instance(dip),
                SAVED_CONFIG_REGS_MASK);
        }
    } else {
        if (ddi_prop_lookup_byte_array(DDI_DEV_T_ANY, dip,
            DDI_PROP_DONTPASS | DDI_PROP_NOTPROM, SAVED_CONFIG_REGS,
            (uchar_t **)&regbuf, &elements) != DDI_PROP_SUCCESS) {

            pci_config_teardown(&confhdl);
            return (DDI_FAILURE);
        }

        chs_p = (pci_config_header_state_t *)regbuf;
        pci_config_put16(confhdl, PCI_CONF_COMM,
            chs_p->chs_command);
        if ((chs_p->chs_header_type & PCI_HEADER_TYPE_M) ==
            PCI_HEADER_ONE) {
            pci_config_put16(confhdl, PCI_BCNF_BCNTRL,
                chs_p->chs_bridge_control);
        }
        pci_config_put8(confhdl, PCI_CONF_CACHE_LINESZ,
            chs_p->chs_cache_line_size);
        pci_config_put8(confhdl, PCI_CONF_LATENCY_TIMER,
            chs_p->chs_latency_timer);
        if ((chs_p->chs_header_type & PCI_HEADER_TYPE_M) ==
            PCI_HEADER_ONE)
            pci_config_put8(confhdl, PCI_BCNF_LATENCY_TIMER,
                chs_p->chs_sec_latency_timer);

        pci_config_put32(confhdl, PCI_CONF_BASE0, chs_p->chs_base0);
        pci_config_put32(confhdl, PCI_CONF_BASE1, chs_p->chs_base1);
        pci_config_put32(confhdl, PCI_CONF_BASE2, chs_p->chs_base2);
        pci_config_put32(confhdl, PCI_CONF_BASE3, chs_p->chs_base3);
        pci_config_put32(confhdl, PCI_CONF_BASE4, chs_p->chs_base4);
        pci_config_put32(confhdl, PCI_CONF_BASE5, chs_p->chs_base5);

        if (ddi_prop_lookup_byte_array(DDI_DEV_T_ANY, dip,
            DDI_PROP_DONTPASS | DDI_PROP_NOTPROM,
            SAVED_CONFIG_REGS_CAPINFO,
            (uchar_t **)&cap_descp, &elements) == DDI_PROP_SUCCESS) {
            /*
             * PCI capability related regsiters are saved.
             * Restore them based on the description.
             */
            p = (uint32_t *)((caddr_t)regbuf +
                sizeof (pci_config_header_state_t));
            pci_restore_caps(confhdl, p, cap_descp, elements);
            ddi_prop_free(cap_descp);
        }

        ddi_prop_free(regbuf);
    }

    /*
     * Make sure registers are flushed
     */
    (void) pci_config_get32(confhdl, PCI_CONF_BASE5);


    if (ndi_prop_remove(DDI_DEV_T_NONE, dip, SAVED_CONFIG_REGS) !=
        DDI_PROP_SUCCESS) {
        cmn_err(CE_WARN, "%s%d can't remove prop %s",
            ddi_driver_name(dip), ddi_get_instance(dip),
            SAVED_CONFIG_REGS);
    }

    pci_config_teardown(&confhdl);

    return (DDI_SUCCESS);

restoreconfig_err:
    ddi_prop_free(maskbuf);
    if (ndi_prop_remove(DDI_DEV_T_NONE, dip, SAVED_CONFIG_REGS_MASK) !=
        DDI_PROP_SUCCESS) {
        cmn_err(CE_WARN, "%s%d can't remove prop %s",
            ddi_driver_name(dip), ddi_get_instance(dip),
            SAVED_CONFIG_REGS_MASK);
    }
    pci_config_teardown(&confhdl);
    return (DDI_FAILURE);
}

/*ARGSUSED*/
static int
pci_lookup_pmcap(dev_info_t *dip, ddi_acc_handle_t conf_hdl,
    uint16_t *pmcap_offsetp)
{
    uint8_t cap_ptr;
    uint8_t cap_id;
    uint8_t header_type;
    uint16_t status;

    header_type = pci_config_get8(conf_hdl, PCI_CONF_HEADER);
    header_type &= PCI_HEADER_TYPE_M;

    /* we don't deal with bridges, etc here */
    if (header_type != PCI_HEADER_ZERO) {
        return (DDI_FAILURE);
    }

    status = pci_config_get16(conf_hdl, PCI_CONF_STAT);
    if ((status & PCI_STAT_CAP) == 0) {
        return (DDI_FAILURE);
    }

    cap_ptr = pci_config_get8(conf_hdl, PCI_CONF_CAP_PTR);

    /*
     * Walk the capabilities searching for a PM entry.
     */
    while (cap_ptr != PCI_CAP_NEXT_PTR_NULL) {
        cap_id = pci_config_get8(conf_hdl, cap_ptr + PCI_CAP_ID);
        if (cap_id == PCI_CAP_ID_PM) {
            break;
        }
        cap_ptr = pci_config_get8(conf_hdl,
            cap_ptr + PCI_CAP_NEXT_PTR);
    }

    if (cap_ptr == PCI_CAP_NEXT_PTR_NULL) {
        return (DDI_FAILURE);
    }
    *pmcap_offsetp = cap_ptr;
    return (DDI_SUCCESS);
}

/*
 * Do common pci-specific suspend actions:
 *  - enable wakeup if appropriate for the device
 *  - put device in lowest D-state that supports wakeup, or D3 if none
 *  - turn off bus mastering in control register
 * For lack of per-dip storage (parent private date is pretty busy)
 * we use properties to store the necessary context
 * To avoid grotting through pci config space on every suspend,
 * we leave the prop in existence after resume, cause we know that
 * the detach framework code will dispose of it for us.
 */

typedef struct pci_pm_context {
    int     ppc_flags;
    uint16_t    ppc_cap_offset; /* offset in config space to pm cap */
    uint16_t    ppc_pmcsr;  /* need this too */
    uint16_t    ppc_suspend_level;
} pci_pm_context_t;

#define SAVED_PM_CONTEXT    "pci-pm-context"

/* values for ppc_flags */
#define PPCF_NOPMCAP    1

/*
 * Handle pci-specific suspend processing
 *   PM CSR and PCI CMD are saved by pci_save_config_regs().
 *   If device can wake up system via PME, enable it to do so
 *   Set device power level to lowest that can generate PME, or D3 if none can
 *   Turn off bus master enable in pci command register
 */
#if defined(__x86)
extern int acpi_ddi_setwake(dev_info_t *dip, int level);
#endif

int
pci_post_suspend(dev_info_t *dip)
{
    pci_pm_context_t *p;
    uint16_t    pmcap, pmcsr, pcicmd;
    uint_t length;
    int ret;
    int fromprop = 1;   /* source of memory *p */
    ddi_acc_handle_t hdl;

    PMD(PMD_SX, ("pci_post_suspend %s:%d\n",
        ddi_driver_name(dip), ddi_get_instance(dip)))

    if (pci_save_config_regs(dip) != DDI_SUCCESS) {
        return (DDI_FAILURE);
    }

    if (pci_config_setup(dip, &hdl) != DDI_SUCCESS) {
        return (DDI_FAILURE);
    }

    if (ddi_prop_lookup_byte_array(DDI_DEV_T_ANY, dip,
        DDI_PROP_DONTPASS | DDI_PROP_NOTPROM,
        SAVED_PM_CONTEXT, (uchar_t **)&p, &length) != DDI_PROP_SUCCESS) {
        p = (pci_pm_context_t *)kmem_zalloc(sizeof (*p), KM_SLEEP);
        fromprop = 0;
        if (pci_lookup_pmcap(dip, hdl,
            &p->ppc_cap_offset) != DDI_SUCCESS) {
            p->ppc_flags |= PPCF_NOPMCAP;
            ret = ndi_prop_update_byte_array(DDI_DEV_T_NONE, dip,
                SAVED_PM_CONTEXT, (uchar_t *)p,
                sizeof (pci_pm_context_t));
            if (ret != DDI_PROP_SUCCESS) {
                (void) ddi_prop_remove(DDI_DEV_T_NONE, dip,
                    SAVED_PM_CONTEXT);
                ret = DDI_FAILURE;
            } else {
                ret = DDI_SUCCESS;
            }
            kmem_free(p, sizeof (*p));
            pci_config_teardown(&hdl);
            return (DDI_SUCCESS);
        }
        /*
         * Upon suspend, set the power level to the lowest that can
         * wake the system.  If none can, then set to lowest.
         * XXX later we will need to check policy to see if this
         * XXX device has had wakeup disabled
         */
        pmcap = pci_config_get16(hdl, p->ppc_cap_offset + PCI_PMCAP);
        if ((pmcap & PCI_PMCAP_D3COLD_PME) != 0)
            p->ppc_suspend_level =
                (PCI_PMCSR_PME_EN | PCI_PMCSR_D3HOT);
        else if ((pmcap & (PCI_PMCAP_D3HOT_PME | PCI_PMCAP_D2_PME)) !=
            0)
            p->ppc_suspend_level = PCI_PMCSR_PME_EN | PCI_PMCSR_D2;
        else if ((pmcap & PCI_PMCAP_D1_PME) != 0)
            p->ppc_suspend_level = PCI_PMCSR_PME_EN | PCI_PMCSR_D1;
        else if ((pmcap & PCI_PMCAP_D0_PME) != 0)
            p->ppc_suspend_level = PCI_PMCSR_PME_EN | PCI_PMCSR_D0;
        else
            p->ppc_suspend_level = PCI_PMCSR_D3HOT;

        /*
         * we defer updating the property to catch the saved
         * register values as well
         */
    }
    /* If we set this in kmem_zalloc'd memory, we already returned above */
    if ((p->ppc_flags & PPCF_NOPMCAP) != 0) {
        ddi_prop_free(p);
        pci_config_teardown(&hdl);
        return (DDI_SUCCESS);
    }


    /*
     * Turn off (Bus) Master Enable, since acpica will be turning off
     * bus master aribitration
     */
    pcicmd = pci_config_get16(hdl, PCI_CONF_COMM);
    pcicmd &= ~PCI_COMM_ME;
    pci_config_put16(hdl, PCI_CONF_COMM, pcicmd);

    /*
     * set pm csr
     */
    pmcsr = pci_config_get16(hdl, p->ppc_cap_offset + PCI_PMCSR);
    p->ppc_pmcsr = pmcsr;
    pmcsr &= (PCI_PMCSR_STATE_MASK);
    pmcsr |= (PCI_PMCSR_PME_STAT | p->ppc_suspend_level);
    pci_config_put16(hdl, p->ppc_cap_offset + PCI_PMCSR, pmcsr);

#if defined(__x86)
    /*
     * Arrange for platform wakeup enabling
     */
    if ((p->ppc_suspend_level & PCI_PMCSR_PME_EN) != 0) {
        int retval;

        retval = acpi_ddi_setwake(dip, 3);  /* XXX 3 for now */
        if (retval) {
            PMD(PMD_SX, ("pci_post_suspend, setwake %s@%s rets "
                "%x\n", PM_NAME(dip), PM_ADDR(dip), retval));
        }
    }
#endif

    /*
     * Push out saved register values
     */
    ret = ndi_prop_update_byte_array(DDI_DEV_T_NONE, dip, SAVED_PM_CONTEXT,
        (uchar_t *)p, sizeof (pci_pm_context_t));
    if (ret == DDI_PROP_SUCCESS) {
        if (fromprop)
            ddi_prop_free(p);
        else
            kmem_free(p, sizeof (*p));
        pci_config_teardown(&hdl);
        return (DDI_SUCCESS);
    }
    /* Failed; put things back the way we found them */
    (void) pci_restore_config_regs(dip);
    if (fromprop)
        ddi_prop_free(p);
    else
        kmem_free(p, sizeof (*p));
    (void) ddi_prop_remove(DDI_DEV_T_NONE, dip, SAVED_PM_CONTEXT);
    pci_config_teardown(&hdl);
    return (DDI_FAILURE);
}

/*
 * The inverse of pci_post_suspend; handle pci-specific resume processing
 *   First, turn device back on, then restore config space.
 */

int
pci_pre_resume(dev_info_t *dip)
{
    ddi_acc_handle_t hdl;
    pci_pm_context_t *p;
    /* E_FUNC_SET_NOT_USED */
    uint16_t    pmcap, pmcsr;
    int flags;
    uint_t length;
    clock_t drv_usectohz(clock_t microsecs);
#if defined(__x86)
    uint16_t    suspend_level;
#endif

    PMD(PMD_SX, ("pci_pre_resume %s:%d\n", ddi_driver_name(dip),
        ddi_get_instance(dip)))
    if (ddi_prop_lookup_byte_array(DDI_DEV_T_ANY, dip,
        DDI_PROP_DONTPASS | DDI_PROP_NOTPROM,
        SAVED_PM_CONTEXT, (uchar_t **)&p, &length) != DDI_PROP_SUCCESS) {
        return (DDI_FAILURE);
    }
    flags = p->ppc_flags;
    pmcap = p->ppc_cap_offset;
    pmcsr = p->ppc_pmcsr;
#if defined(__x86)
    suspend_level = p->ppc_suspend_level;
#endif
    ddi_prop_free(p);
    if ((flags & PPCF_NOPMCAP) != 0) {
        return (DDI_SUCCESS);
    }
#if defined(__x86)
    /*
     * Turn platform wake enable back off
     */
    if ((suspend_level & PCI_PMCSR_PME_EN) != 0) {
        int retval;

        retval = acpi_ddi_setwake(dip, 0);  /* 0 for now */
        if (retval) {
            PMD(PMD_SX, ("pci_pre_resume, setwake %s@%s rets "
                "%x\n", PM_NAME(dip), PM_ADDR(dip), retval));
        }
    }
#endif
    if (pci_config_setup(dip, &hdl) != DDI_SUCCESS) {
        return (DDI_FAILURE);
    }
    pci_config_put16(hdl, pmcap + PCI_PMCSR, pmcsr);
    delay(drv_usectohz(10000)); /* PCI PM spec D3->D0 (10ms) */
    pci_config_teardown(&hdl);
    (void) pci_restore_config_regs(dip);    /* fudges D-state! */
    return (DDI_SUCCESS);
}