998 obsolete DMA driver interfaces should be removed

[unleashed.git] / usr / src / uts / sun4 / io / px / px_dma.c

/*
 * 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 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/*
 * Copyright 2012 Garrett D'Amore <garrett@damore.org>.  All rights reserved.
 */

/*
 * PCI Express nexus DVMA and DMA core routines:
 *      dma_map/dma_bind_handle implementation
 *      bypass and peer-to-peer support
 *      fast track DVMA space allocation
 *      runtime DVMA debug
 */
#include <sys/types.h>
#include <sys/kmem.h>
#include <sys/async.h>
#include <sys/sysmacros.h>
#include <sys/sunddi.h>
#include <sys/ddi_impldefs.h>
#include "px_obj.h"

/*LINTLIBRARY*/

/*
 * px_dma_allocmp - Allocate a pci dma implementation structure
 *
 * An extra ddi_dma_attr structure is bundled with the usual ddi_dma_impl
 * to hold unmodified device limits. The ddi_dma_attr inside the
 * ddi_dma_impl structure is augumented with system limits to enhance
 * DVMA performance at runtime. The unaugumented device limits saved
 * right after (accessed through (ddi_dma_attr_t *)(mp + 1)) is used
 * strictly for peer-to-peer transfers which do not obey system limits.
 *
 * return: DDI_SUCCESS DDI_DMA_NORESOURCES
 */
ddi_dma_impl_t *
px_dma_allocmp(dev_info_t *dip, dev_info_t *rdip, int (*waitfp)(caddr_t),
        caddr_t arg)
{
        register ddi_dma_impl_t *mp;
        int sleep = (waitfp == DDI_DMA_SLEEP) ? KM_SLEEP : KM_NOSLEEP;

        /* Caution: we don't use zalloc to enhance performance! */
        if ((mp = kmem_alloc(sizeof (px_dma_hdl_t), sleep)) == 0) {
                DBG(DBG_DMA_MAP, dip, "can't alloc dma_handle\n");
                if (waitfp != DDI_DMA_DONTWAIT) {
                        DBG(DBG_DMA_MAP, dip, "alloc_mp kmem cb\n");
                        ddi_set_callback(waitfp, arg, &px_kmem_clid);
                }
                return (mp);
        }

        mp->dmai_rdip = rdip;
        mp->dmai_flags = 0;
        mp->dmai_pfnlst = NULL;
        mp->dmai_winlst = NULL;

        /*
         * kmem_alloc debug: the following fields are not zero-ed
         * mp->dmai_mapping = 0;
         * mp->dmai_size = 0;
         * mp->dmai_offset = 0;
         * mp->dmai_minxfer = 0;
         * mp->dmai_burstsizes = 0;
         * mp->dmai_ndvmapages = 0;
         * mp->dmai_pool/roffset = 0;
         * mp->dmai_rflags = 0;
         * mp->dmai_inuse/flags
         * mp->dmai_nwin = 0;
         * mp->dmai_winsize = 0;
         * mp->dmai_nexus_private/tte = 0;
         * mp->dmai_iopte/pfnlst
         * mp->dmai_sbi/pfn0 = 0;
         * mp->dmai_minfo/winlst/fdvma
         * mp->dmai_rdip
         * bzero(&mp->dmai_object, sizeof (ddi_dma_obj_t));
         * bzero(&mp->dmai_attr, sizeof (ddi_dma_attr_t));
         * mp->dmai_cookie = 0;
         */

        mp->dmai_attr.dma_attr_version = (uint_t)DMA_ATTR_VERSION;
        mp->dmai_attr.dma_attr_flags = (uint_t)0;
        mp->dmai_fault = 0;
        mp->dmai_fault_check = NULL;
        mp->dmai_fault_notify = NULL;

        mp->dmai_error.err_ena = 0;
        mp->dmai_error.err_status = DDI_FM_OK;
        mp->dmai_error.err_expected = DDI_FM_ERR_UNEXPECTED;
        mp->dmai_error.err_ontrap = NULL;
        mp->dmai_error.err_fep = NULL;
        mp->dmai_error.err_cf = NULL;

        /*
         * The bdf protection value is set to immediate child
         * at first. It gets modified by switch/bridge drivers
         * as the code traverses down the fabric topology.
         *
         * XXX No IOMMU protection for broken devices.
         */
        ASSERT((intptr_t)ddi_get_parent_data(rdip) >> 1 == 0);
        mp->dmai_bdf = ((intptr_t)ddi_get_parent_data(rdip) == 1) ?
            PCIE_INVALID_BDF : pcie_get_bdf_for_dma_xfer(dip, rdip);

        ndi_fmc_insert(rdip, DMA_HANDLE, mp, NULL);
        return (mp);
}

void
px_dma_freemp(ddi_dma_impl_t *mp)
{
        ndi_fmc_remove(mp->dmai_rdip, DMA_HANDLE, mp);
        if (mp->dmai_ndvmapages > 1)
                px_dma_freepfn(mp);
        if (mp->dmai_winlst)
                px_dma_freewin(mp);
        kmem_free(mp, sizeof (px_dma_hdl_t));
}

void
px_dma_freepfn(ddi_dma_impl_t *mp)
{
        void *addr = mp->dmai_pfnlst;
        if (addr) {
                size_t npages = mp->dmai_ndvmapages;
                if (npages > 1)
                        kmem_free(addr, npages * sizeof (px_iopfn_t));
                mp->dmai_pfnlst = NULL;
        }
        mp->dmai_ndvmapages = 0;
}

/*
 * px_dma_lmts2hdl - alloate a ddi_dma_impl_t, validate practical limits
 *                      and convert dmareq->dmar_limits to mp->dmai_attr
 *
 * ddi_dma_impl_t member modified     input
 * ------------------------------------------------------------------------
 * mp->dmai_minxfer                 - dev
 * mp->dmai_burstsizes              - dev
 * mp->dmai_flags                   - no limit? peer-to-peer only?
 *
 * ddi_dma_attr member modified       input
 * ------------------------------------------------------------------------
 * mp->dmai_attr.dma_attr_addr_lo   - dev lo, sys lo
 * mp->dmai_attr.dma_attr_addr_hi   - dev hi, sys hi
 * mp->dmai_attr.dma_attr_count_max - dev count max, dev/sys lo/hi delta
 * mp->dmai_attr.dma_attr_seg       - 0         (no nocross   restriction)
 * mp->dmai_attr.dma_attr_align     - 1         (no alignment restriction)
 *
 * The dlim_dmaspeed member of dmareq->dmar_limits is ignored.
 */
ddi_dma_impl_t *
px_dma_lmts2hdl(dev_info_t *dip, dev_info_t *rdip, px_mmu_t *mmu_p,
        ddi_dma_req_t *dmareq)
{
        ddi_dma_impl_t *mp;
        ddi_dma_attr_t *attr_p;
        uint64_t syslo          = mmu_p->mmu_dvma_base;
        uint64_t syshi          = mmu_p->mmu_dvma_end;
        uint64_t fasthi         = mmu_p->mmu_dvma_fast_end;
        ddi_dma_lim_t *lim_p    = dmareq->dmar_limits;
        uint32_t count_max      = lim_p->dlim_cntr_max;
        uint64_t lo             = lim_p->dlim_addr_lo;
        uint64_t hi             = lim_p->dlim_addr_hi;
        if (hi <= lo) {
                DBG(DBG_DMA_MAP, dip, "Bad limits\n");
                return ((ddi_dma_impl_t *)DDI_DMA_NOMAPPING);
        }
        if (!count_max)
                count_max--;

        if (!(mp = px_dma_allocmp(dip, rdip, dmareq->dmar_fp,
            dmareq->dmar_arg)))
                return (NULL);

        /* store original dev input at the 2nd ddi_dma_attr */
        attr_p = PX_DEV_ATTR(mp);
        SET_DMAATTR(attr_p, lo, hi, -1, count_max);
        SET_DMAALIGN(attr_p, 1);

        lo = MAX(lo, syslo);
        hi = MIN(hi, syshi);
        if (hi <= lo)
                mp->dmai_flags |= PX_DMAI_FLAGS_PEER_ONLY;
        count_max = MIN(count_max, hi - lo);

        if (PX_DEV_NOSYSLIMIT(lo, hi, syslo, fasthi, 1))
                mp->dmai_flags |= PX_DMAI_FLAGS_NOFASTLIMIT |
                    PX_DMAI_FLAGS_NOSYSLIMIT;
        else {
                if (PX_DEV_NOFASTLIMIT(lo, hi, syslo, syshi, 1))
                        mp->dmai_flags |= PX_DMAI_FLAGS_NOFASTLIMIT;
        }
        if (PX_DMA_NOCTX(rdip))
                mp->dmai_flags |= PX_DMAI_FLAGS_NOCTX;

        /* store augumented dev input to mp->dmai_attr */
        mp->dmai_burstsizes     = lim_p->dlim_burstsizes;
        attr_p = &mp->dmai_attr;
        SET_DMAATTR(attr_p, lo, hi, -1, count_max);
        SET_DMAALIGN(attr_p, 1);
        return (mp);
}

/*
 * Called from px_attach to check for bypass dma support and set
 * flags accordingly.
 */
int
px_dma_attach(px_t *px_p)
{
        uint64_t baddr;

        if (px_lib_iommu_getbypass(px_p->px_dip, 0ull,
            PCI_MAP_ATTR_WRITE|PCI_MAP_ATTR_READ,
            &baddr) != DDI_ENOTSUP)
                /* ignore all other errors */
                px_p->px_dev_caps |= PX_BYPASS_DMA_ALLOWED;

        px_p->px_dma_sync_opt = ddi_prop_get_int(DDI_DEV_T_ANY,
            px_p->px_dip, DDI_PROP_DONTPASS, "dma-sync-options", 0);

        if (px_p->px_dma_sync_opt != 0)
                px_p->px_dev_caps |= PX_DMA_SYNC_REQUIRED;

        return (DDI_SUCCESS);
}

/*
 * px_dma_attr2hdl
 *
 * This routine is called from the alloc handle entry point to sanity check the
 * dma attribute structure.
 *
 * use by: px_dma_allochdl()
 *
 * return value:
 *
 *      DDI_SUCCESS             - on success
 *      DDI_DMA_BADATTR         - attribute has invalid version number
 *                                or address limits exclude dvma space
 */
int
px_dma_attr2hdl(px_t *px_p, ddi_dma_impl_t *mp)
{
        px_mmu_t *mmu_p = px_p->px_mmu_p;
        uint64_t syslo, syshi;
        int     ret;
        ddi_dma_attr_t *attrp           = PX_DEV_ATTR(mp);
        uint64_t hi                     = attrp->dma_attr_addr_hi;
        uint64_t lo                     = attrp->dma_attr_addr_lo;
        uint64_t align                  = attrp->dma_attr_align;
        uint64_t nocross                = attrp->dma_attr_seg;
        uint64_t count_max              = attrp->dma_attr_count_max;

        DBG(DBG_DMA_ALLOCH, px_p->px_dip, "attrp=%p cntr_max=%x.%08x\n",
            attrp, HI32(count_max), LO32(count_max));
        DBG(DBG_DMA_ALLOCH, px_p->px_dip, "hi=%x.%08x lo=%x.%08x\n",
            HI32(hi), LO32(hi), HI32(lo), LO32(lo));
        DBG(DBG_DMA_ALLOCH, px_p->px_dip, "seg=%x.%08x align=%x.%08x\n",
            HI32(nocross), LO32(nocross), HI32(align), LO32(align));

        if (!nocross)
                nocross--;
        if (attrp->dma_attr_flags & DDI_DMA_FORCE_PHYSICAL) { /* BYPASS */

                DBG(DBG_DMA_ALLOCH, px_p->px_dip, "bypass mode\n");
                /*
                 * If Bypass DMA is not supported, return error so that
                 * target driver can fall back to dvma mode of operation
                 */
                if (!(px_p->px_dev_caps & PX_BYPASS_DMA_ALLOWED))
                        return (DDI_DMA_BADATTR);
                mp->dmai_flags |= PX_DMAI_FLAGS_BYPASSREQ;
                if (nocross != UINT64_MAX)
                        return (DDI_DMA_BADATTR);
                if (align && (align > MMU_PAGE_SIZE))
                        return (DDI_DMA_BADATTR);
                align = 1; /* align on 1 page boundary */

                /* do a range check and get the limits */
                ret = px_lib_dma_bypass_rngchk(px_p->px_dip, attrp,
                    &syslo, &syshi);
                if (ret != DDI_SUCCESS)
                        return (ret);
        } else { /* MMU_XLATE or PEER_TO_PEER */
                align = MAX(align, MMU_PAGE_SIZE) - 1;
                if ((align & nocross) != align) {
                        dev_info_t *rdip = mp->dmai_rdip;
                        cmn_err(CE_WARN, "%s%d dma_attr_seg not aligned",
                            NAMEINST(rdip));
                        return (DDI_DMA_BADATTR);
                }
                align = MMU_BTOP(align + 1);
                syslo = mmu_p->mmu_dvma_base;
                syshi = mmu_p->mmu_dvma_end;
        }
        if (hi <= lo) {
                dev_info_t *rdip = mp->dmai_rdip;
                cmn_err(CE_WARN, "%s%d limits out of range", NAMEINST(rdip));
                return (DDI_DMA_BADATTR);
        }
        lo = MAX(lo, syslo);
        hi = MIN(hi, syshi);
        if (!count_max)
                count_max--;

        DBG(DBG_DMA_ALLOCH, px_p->px_dip, "hi=%x.%08x, lo=%x.%08x\n",
            HI32(hi), LO32(hi), HI32(lo), LO32(lo));
        if (hi <= lo) {
                /*
                 * If this is an IOMMU bypass access, the caller can't use
                 * the required addresses, so fail it.  Otherwise, it's
                 * peer-to-peer; ensure that the caller has no alignment or
                 * segment size restrictions.
                 */
                if ((mp->dmai_flags & PX_DMAI_FLAGS_BYPASSREQ) ||
                    (nocross < UINT32_MAX) || (align > 1))
                        return (DDI_DMA_BADATTR);

                mp->dmai_flags |= PX_DMAI_FLAGS_PEER_ONLY;
        } else /* set practical counter_max value */
                count_max = MIN(count_max, hi - lo);

        if (PX_DEV_NOSYSLIMIT(lo, hi, syslo, syshi, align))
                mp->dmai_flags |= PX_DMAI_FLAGS_NOSYSLIMIT |
                    PX_DMAI_FLAGS_NOFASTLIMIT;
        else {
                syshi = mmu_p->mmu_dvma_fast_end;
                if (PX_DEV_NOFASTLIMIT(lo, hi, syslo, syshi, align))
                        mp->dmai_flags |= PX_DMAI_FLAGS_NOFASTLIMIT;
        }
        if (PX_DMA_NOCTX(mp->dmai_rdip))
                mp->dmai_flags |= PX_DMAI_FLAGS_NOCTX;

        mp->dmai_burstsizes     = attrp->dma_attr_burstsizes;
        attrp = &mp->dmai_attr;
        SET_DMAATTR(attrp, lo, hi, nocross, count_max);
        return (DDI_SUCCESS);
}

#define TGT_PFN_INBETWEEN(pfn, bgn, end) ((pfn >= bgn) && (pfn <= end))

/*
 * px_dma_type - determine which of the three types DMA (peer-to-peer,
 *              mmu bypass, or mmu translate) we are asked to do.
 *              Also checks pfn0 and rejects any non-peer-to-peer
 *              requests for peer-only devices.
 *
 *      return values:
 *              DDI_DMA_NOMAPPING - can't get valid pfn0, or bad dma type
 *              DDI_SUCCESS
 *
 *      dma handle members affected (set on exit):
 *      mp->dmai_object         - dmareq->dmar_object
 *      mp->dmai_rflags         - consistent?, nosync?, dmareq->dmar_flags
 *      mp->dmai_flags          - DMA type
 *      mp->dmai_pfn0           - 1st page pfn (if va/size pair and not shadow)
 *      mp->dmai_roffset        - initialized to starting MMU page offset
 *      mp->dmai_ndvmapages     - # of total MMU pages of entire object
 */
int
px_dma_type(px_t *px_p, ddi_dma_req_t *dmareq, ddi_dma_impl_t *mp)
{
        dev_info_t *dip = px_p->px_dip;
        ddi_dma_obj_t *dobj_p = &dmareq->dmar_object;
        px_pec_t *pec_p = px_p->px_pec_p;
        uint32_t offset;
        pfn_t pfn0;
        uint_t redzone;

        mp->dmai_rflags = dmareq->dmar_flags & DMP_DDIFLAGS;

        if (!(px_p->px_dev_caps & PX_DMA_SYNC_REQUIRED))
                mp->dmai_rflags |= DMP_NOSYNC;

        switch (dobj_p->dmao_type) {
        case DMA_OTYP_BUFVADDR:
        case DMA_OTYP_VADDR: {
                page_t **pplist = dobj_p->dmao_obj.virt_obj.v_priv;
                caddr_t vaddr = dobj_p->dmao_obj.virt_obj.v_addr;

                DBG(DBG_DMA_MAP, dip, "vaddr=%p pplist=%p\n", vaddr, pplist);
                offset = (ulong_t)vaddr & MMU_PAGE_OFFSET;
                if (pplist) {                           /* shadow list */
                        mp->dmai_flags |= PX_DMAI_FLAGS_PGPFN;
                        pfn0 = page_pptonum(*pplist);
                } else {
                        struct as *as_p = dobj_p->dmao_obj.virt_obj.v_as;
                        struct hat *hat_p = as_p ? as_p->a_hat : kas.a_hat;
                        pfn0 = hat_getpfnum(hat_p, vaddr);
                }
                }
                break;

        case DMA_OTYP_PAGES:
                offset = dobj_p->dmao_obj.pp_obj.pp_offset;
                mp->dmai_flags |= PX_DMAI_FLAGS_PGPFN;
                pfn0 = page_pptonum(dobj_p->dmao_obj.pp_obj.pp_pp);
                break;

        case DMA_OTYP_PADDR:
        default:
                cmn_err(CE_WARN, "%s%d requested unsupported dma type %x",
                    NAMEINST(mp->dmai_rdip), dobj_p->dmao_type);
                return (DDI_DMA_NOMAPPING);
        }
        if (pfn0 == PFN_INVALID) {
                cmn_err(CE_WARN, "%s%d: invalid pfn0 for DMA object %p",
                    NAMEINST(dip), dobj_p);
                return (DDI_DMA_NOMAPPING);
        }
        if (TGT_PFN_INBETWEEN(pfn0, pec_p->pec_base32_pfn,
            pec_p->pec_last32_pfn)) {
                mp->dmai_flags |= PX_DMAI_FLAGS_PTP|PX_DMAI_FLAGS_PTP32;
                goto done;      /* leave bypass and dvma flag as 0 */
        } else if (TGT_PFN_INBETWEEN(pfn0, pec_p->pec_base64_pfn,
            pec_p->pec_last64_pfn)) {
                mp->dmai_flags |= PX_DMAI_FLAGS_PTP|PX_DMAI_FLAGS_PTP64;
                goto done;      /* leave bypass and dvma flag as 0 */
        }
        if (PX_DMA_ISPEERONLY(mp)) {
                dev_info_t *rdip = mp->dmai_rdip;
                cmn_err(CE_WARN, "Bad peer-to-peer req %s%d", NAMEINST(rdip));
                return (DDI_DMA_NOMAPPING);
        }

        redzone = (mp->dmai_rflags & DDI_DMA_REDZONE) ||
            (mp->dmai_flags & PX_DMAI_FLAGS_MAP_BUFZONE) ?
            PX_DMAI_FLAGS_REDZONE : 0;

        mp->dmai_flags |= (mp->dmai_flags & PX_DMAI_FLAGS_BYPASSREQ) ?
            PX_DMAI_FLAGS_BYPASS : (PX_DMAI_FLAGS_DVMA | redzone);
done:
        mp->dmai_object  = *dobj_p;                     /* whole object    */
        mp->dmai_pfn0    = (void *)pfn0;                /* cache pfn0      */
        mp->dmai_roffset = offset;                      /* win0 pg0 offset */
        mp->dmai_ndvmapages = MMU_BTOPR(offset + mp->dmai_object.dmao_size);
        return (DDI_SUCCESS);
}

/*
 * px_dma_pgpfn - set up pfnlst array according to pages
 *      VA/size pair: <shadow IO, bypass, peer-to-peer>, or OTYP_PAGES
 */
/*ARGSUSED*/
static int
px_dma_pgpfn(px_t *px_p, ddi_dma_impl_t *mp, uint_t npages)
{
        int i;
        dev_info_t *dip = px_p->px_dip;

        switch (mp->dmai_object.dmao_type) {
        case DMA_OTYP_BUFVADDR:
        case DMA_OTYP_VADDR: {
                page_t **pplist = mp->dmai_object.dmao_obj.virt_obj.v_priv;
                DBG(DBG_DMA_MAP, dip, "shadow pplist=%p, %x pages, pfns=",
                    pplist, npages);
                for (i = 1; i < npages; i++) {
                        px_iopfn_t pfn = page_pptonum(pplist[i]);
                        PX_SET_MP_PFN1(mp, i, pfn);
                        DBG(DBG_DMA_MAP|DBG_CONT, dip, "%x ", pfn);
                }
                DBG(DBG_DMA_MAP|DBG_CONT, dip, "\n");
                }
                break;

        case DMA_OTYP_PAGES: {
                page_t *pp = mp->dmai_object.dmao_obj.pp_obj.pp_pp->p_next;
                DBG(DBG_DMA_MAP, dip, "pp=%p pfns=", pp);
                for (i = 1; i < npages; i++, pp = pp->p_next) {
                        px_iopfn_t pfn = page_pptonum(pp);
                        PX_SET_MP_PFN1(mp, i, pfn);
                        DBG(DBG_DMA_MAP|DBG_CONT, dip, "%x ", pfn);
                }
                DBG(DBG_DMA_MAP|DBG_CONT, dip, "\n");
                }
                break;

        default:        /* check is already done by px_dma_type */
                ASSERT(0);
                break;
        }
        return (DDI_SUCCESS);
}

/*
 * px_dma_vapfn - set up pfnlst array according to VA
 *      VA/size pair: <normal, bypass, peer-to-peer>
 *      pfn0 is skipped as it is already done.
 *      In this case, the cached pfn0 is used to fill pfnlst[0]
 */
static int
px_dma_vapfn(px_t *px_p, ddi_dma_impl_t *mp, uint_t npages)
{
        dev_info_t *dip = px_p->px_dip;
        int i;
        caddr_t vaddr = (caddr_t)mp->dmai_object.dmao_obj.virt_obj.v_as;
        struct hat *hat_p = vaddr ? ((struct as *)vaddr)->a_hat : kas.a_hat;

        vaddr = mp->dmai_object.dmao_obj.virt_obj.v_addr + MMU_PAGE_SIZE;
        for (i = 1; i < npages; i++, vaddr += MMU_PAGE_SIZE) {
                px_iopfn_t pfn = hat_getpfnum(hat_p, vaddr);
                if (pfn == PFN_INVALID)
                        goto err_badpfn;
                PX_SET_MP_PFN1(mp, i, pfn);
                DBG(DBG_DMA_BINDH, dip, "px_dma_vapfn: mp=%p pfnlst[%x]=%x\n",
                    mp, i, pfn);
        }
        return (DDI_SUCCESS);
err_badpfn:
        cmn_err(CE_WARN, "%s%d: bad page frame vaddr=%p", NAMEINST(dip), vaddr);
        return (DDI_DMA_NOMAPPING);
}

/*
 * px_dma_pfn - Fills pfn list for all pages being DMA-ed.
 *
 * dependencies:
 *      mp->dmai_ndvmapages     - set to total # of dma pages
 *
 * return value:
 *      DDI_SUCCESS
 *      DDI_DMA_NOMAPPING
 */
int
px_dma_pfn(px_t *px_p, ddi_dma_req_t *dmareq, ddi_dma_impl_t *mp)
{
        uint32_t npages = mp->dmai_ndvmapages;
        int (*waitfp)(caddr_t) = dmareq->dmar_fp;
        int i, ret, peer = PX_DMA_ISPTP(mp);
        int peer32 = PX_DMA_ISPTP32(mp);
        dev_info_t *dip = px_p->px_dip;

        px_pec_t *pec_p = px_p->px_pec_p;
        px_iopfn_t pfn_base = peer32 ? pec_p->pec_base32_pfn :
            pec_p->pec_base64_pfn;
        px_iopfn_t pfn_last = peer32 ? pec_p->pec_last32_pfn :
            pec_p->pec_last64_pfn;
        px_iopfn_t pfn_adj = peer ? pfn_base : 0;

        DBG(DBG_DMA_BINDH, dip, "px_dma_pfn: mp=%p pfn0=%x\n",
            mp, PX_MP_PFN0(mp) - pfn_adj);
        /* 1 page: no array alloc/fill, no mixed mode check */
        if (npages == 1) {
                PX_SET_MP_PFN(mp, 0, PX_MP_PFN0(mp) - pfn_adj);
                return (DDI_SUCCESS);
        }
        /* allocate pfn array */
        if (!(mp->dmai_pfnlst = kmem_alloc(npages * sizeof (px_iopfn_t),
            waitfp == DDI_DMA_SLEEP ? KM_SLEEP : KM_NOSLEEP))) {
                if (waitfp != DDI_DMA_DONTWAIT)
                        ddi_set_callback(waitfp, dmareq->dmar_arg,
                            &px_kmem_clid);
                return (DDI_DMA_NORESOURCES);
        }
        /* fill pfn array */
        PX_SET_MP_PFN(mp, 0, PX_MP_PFN0(mp) - pfn_adj); /* pfnlst[0] */
        if ((ret = PX_DMA_ISPGPFN(mp) ? px_dma_pgpfn(px_p, mp, npages) :
            px_dma_vapfn(px_p, mp, npages)) != DDI_SUCCESS)
                goto err;

        /* skip pfn0, check mixed mode and adjust peer to peer pfn */
        for (i = 1; i < npages; i++) {
                px_iopfn_t pfn = PX_GET_MP_PFN1(mp, i);
                if (peer ^ TGT_PFN_INBETWEEN(pfn, pfn_base, pfn_last)) {
                        cmn_err(CE_WARN, "%s%d mixed mode DMA %lx %lx",
                            NAMEINST(mp->dmai_rdip), PX_MP_PFN0(mp), pfn);
                        ret = DDI_DMA_NOMAPPING;        /* mixed mode */
                        goto err;
                }
                DBG(DBG_DMA_MAP, dip,
                    "px_dma_pfn: pfnlst[%x]=%x-%x\n", i, pfn, pfn_adj);
                if (pfn_adj)
                        PX_SET_MP_PFN1(mp, i, pfn - pfn_adj);
        }
        return (DDI_SUCCESS);
err:
        px_dma_freepfn(mp);
        return (ret);
}

/*
 * px_dvma_win() - trim requested DVMA size down to window size
 *      The 1st window starts from offset and ends at page-aligned boundary.
 *      From the 2nd window on, each window starts and ends at page-aligned
 *      boundary except the last window ends at wherever requested.
 *
 *      accesses the following mp-> members:
 *      mp->dmai_attr.dma_attr_count_max
 *      mp->dmai_attr.dma_attr_seg
 *      mp->dmai_roffset   - start offset of 1st window
 *      mp->dmai_rflags (redzone)
 *      mp->dmai_ndvmapages (for 1 page fast path)
 *
 *      sets the following mp-> members:
 *      mp->dmai_size      - xfer size, != winsize if 1st/last win  (not fixed)
 *      mp->dmai_winsize   - window size (no redzone), n * page size    (fixed)
 *      mp->dmai_nwin      - # of DMA windows of entire object          (fixed)
 *      mp->dmai_rflags    - remove partial flag if nwin == 1           (fixed)
 *      mp->dmai_winlst    - NULL, window objects not used for DVMA     (fixed)
 *
 *      fixed - not changed across different DMA windows
 */
/*ARGSUSED*/
int
px_dvma_win(px_t *px_p, ddi_dma_req_t *dmareq, ddi_dma_impl_t *mp)
{
        uint32_t redzone_sz     = PX_HAS_REDZONE(mp) ? MMU_PAGE_SIZE : 0;
        size_t obj_sz           = mp->dmai_object.dmao_size;
        size_t xfer_sz;
        ulong_t pg_off;

        if ((mp->dmai_ndvmapages == 1) && !redzone_sz) {
                mp->dmai_rflags &= ~DDI_DMA_PARTIAL;
                mp->dmai_size = obj_sz;
                mp->dmai_winsize = MMU_PAGE_SIZE;
                mp->dmai_nwin = 1;
                goto done;
        }

        pg_off  = mp->dmai_roffset;
        xfer_sz = obj_sz + redzone_sz;

        /* include redzone in nocross check */  {
                uint64_t nocross = mp->dmai_attr.dma_attr_seg;
                if (xfer_sz + pg_off - 1 > nocross)
                        xfer_sz = nocross - pg_off + 1;
                if (redzone_sz && (xfer_sz <= redzone_sz)) {
                        DBG(DBG_DMA_MAP, px_p->px_dip,
                            "nocross too small: "
                            "%lx(%lx)+%lx+%lx < %llx\n",
                            xfer_sz, obj_sz, pg_off, redzone_sz, nocross);
                        return (DDI_DMA_TOOBIG);
                }
        }
        xfer_sz -= redzone_sz;          /* restore transfer size  */
        /* check counter max */ {
                uint32_t count_max = mp->dmai_attr.dma_attr_count_max;
                if (xfer_sz - 1 > count_max)
                        xfer_sz = count_max + 1;
        }
        if (xfer_sz >= obj_sz) {
                mp->dmai_rflags &= ~DDI_DMA_PARTIAL;
                mp->dmai_size = xfer_sz;
                mp->dmai_winsize = P2ROUNDUP(xfer_sz + pg_off, MMU_PAGE_SIZE);
                mp->dmai_nwin = 1;
                goto done;
        }
        if (!(dmareq->dmar_flags & DDI_DMA_PARTIAL)) {
                DBG(DBG_DMA_MAP, px_p->px_dip, "too big: %lx+%lx+%lx > %lx\n",
                    obj_sz, pg_off, redzone_sz, xfer_sz);
                return (DDI_DMA_TOOBIG);
        }

        xfer_sz = MMU_PTOB(MMU_BTOP(xfer_sz + pg_off)); /* page align */
        mp->dmai_size = xfer_sz - pg_off;       /* 1st window xferrable size */
        mp->dmai_winsize = xfer_sz;             /* redzone not in winsize */
        mp->dmai_nwin = (obj_sz + pg_off + xfer_sz - 1) / xfer_sz;
done:
        mp->dmai_winlst = NULL;
        px_dump_dma_handle(DBG_DMA_MAP, px_p->px_dip, mp);
        return (DDI_SUCCESS);
}

/*
 * fast track cache entry to mmu context, inserts 3 0 bits between
 * upper 6-bits and lower 3-bits of the 9-bit cache entry
 */
#define MMU_FCE_TO_CTX(i)       (((i) << 3) | ((i) & 0x7) | 0x38)

/*
 * px_dvma_map_fast - attempts to map fast trackable DVMA
 */
/*ARGSUSED*/
int
px_dvma_map_fast(px_mmu_t *mmu_p, ddi_dma_impl_t *mp)
{
        uint_t clustsz = px_dvma_page_cache_clustsz;
        uint_t entries = px_dvma_page_cache_entries;
        io_attributes_t attr = PX_GET_TTE_ATTR(mp->dmai_rflags,
            mp->dmai_attr.dma_attr_flags);
        int i = mmu_p->mmu_dvma_addr_scan_start;
        uint8_t *lock_addr = mmu_p->mmu_dvma_cache_locks + i;
        px_dvma_addr_t dvma_pg;
        size_t npages = MMU_BTOP(mp->dmai_winsize);
        dev_info_t *dip = mmu_p->mmu_px_p->px_dip;

        extern uint8_t ldstub(uint8_t *);
        ASSERT(MMU_PTOB(npages) == mp->dmai_winsize);
        ASSERT(npages + PX_HAS_REDZONE(mp) <= clustsz);

        for (; i < entries && ldstub(lock_addr); i++, lock_addr++)
                ;
        if (i >= entries) {
                lock_addr = mmu_p->mmu_dvma_cache_locks;
                i = 0;
                for (; i < entries && ldstub(lock_addr); i++, lock_addr++)
                        ;
                if (i >= entries) {
#ifdef  PX_DMA_PROF
                        px_dvmaft_exhaust++;
#endif  /* PX_DMA_PROF */
                        return (DDI_DMA_NORESOURCES);
                }
        }
        mmu_p->mmu_dvma_addr_scan_start = (i + 1) & (entries - 1);

        i *= clustsz;
        dvma_pg = mmu_p->dvma_base_pg + i;

        if (px_lib_iommu_map(dip, PCI_TSBID(0, i), npages,
            PX_ADD_ATTR_EXTNS(attr, mp->dmai_bdf), (void *)mp, 0,
            MMU_MAP_PFN) != DDI_SUCCESS) {
                DBG(DBG_MAP_WIN, dip, "px_dvma_map_fast: "
                    "px_lib_iommu_map failed\n");
                return (DDI_FAILURE);
        }

        if (!PX_MAP_BUFZONE(mp))
                goto done;

        DBG(DBG_MAP_WIN, dip, "px_dvma_map_fast: redzone pg=%x\n", i + npages);

        ASSERT(PX_HAS_REDZONE(mp));

        if (px_lib_iommu_map(dip, PCI_TSBID(0, i + npages), 1,
            PX_ADD_ATTR_EXTNS(attr, mp->dmai_bdf), (void *)mp, npages - 1,
            MMU_MAP_PFN) != DDI_SUCCESS) {
                DBG(DBG_MAP_WIN, dip, "px_dvma_map_fast: "
                    "mapping REDZONE page failed\n");

                (void) px_lib_iommu_demap(dip, PCI_TSBID(0, i), npages);
                return (DDI_FAILURE);
        }

done:
#ifdef PX_DMA_PROF
        px_dvmaft_success++;
#endif
        mp->dmai_mapping = mp->dmai_roffset | MMU_PTOB(dvma_pg);
        mp->dmai_offset = 0;
        mp->dmai_flags |= PX_DMAI_FLAGS_FASTTRACK;
        PX_SAVE_MP_TTE(mp, attr);       /* save TTE template for unmapping */
        if (PX_DVMA_DBG_ON(mmu_p))
                px_dvma_alloc_debug(mmu_p, (char *)mp->dmai_mapping,
                    mp->dmai_size, mp);
        return (DDI_SUCCESS);
}

/*
 * px_dvma_map: map non-fasttrack DMA
 *              Use quantum cache if single page DMA.
 */
int
px_dvma_map(ddi_dma_impl_t *mp, ddi_dma_req_t *dmareq, px_mmu_t *mmu_p)
{
        uint_t npages = PX_DMA_WINNPGS(mp);
        px_dvma_addr_t dvma_pg, dvma_pg_index;
        void *dvma_addr;
        io_attributes_t attr = PX_GET_TTE_ATTR(mp->dmai_rflags,
            mp->dmai_attr.dma_attr_flags);
        int sleep = dmareq->dmar_fp == DDI_DMA_SLEEP ? VM_SLEEP : VM_NOSLEEP;
        dev_info_t *dip = mp->dmai_rdip;
        int     ret = DDI_SUCCESS;

        /*
         * allocate dvma space resource and map in the first window.
         * (vmem_t *vmp, size_t size,
         *      size_t align, size_t phase, size_t nocross,
         *      void *minaddr, void *maxaddr, int vmflag)
         */
        if ((npages == 1) && !PX_HAS_REDZONE(mp) && PX_HAS_NOSYSLIMIT(mp)) {
                dvma_addr = vmem_alloc(mmu_p->mmu_dvma_map,
                    MMU_PAGE_SIZE, sleep);
                mp->dmai_flags |= PX_DMAI_FLAGS_VMEMCACHE;
#ifdef  PX_DMA_PROF
                px_dvma_vmem_alloc++;
#endif  /* PX_DMA_PROF */
        } else {
                dvma_addr = vmem_xalloc(mmu_p->mmu_dvma_map,
                    MMU_PTOB(npages + PX_HAS_REDZONE(mp)),
                    MAX(mp->dmai_attr.dma_attr_align, MMU_PAGE_SIZE),
                    0,
                    mp->dmai_attr.dma_attr_seg + 1,
                    (void *)mp->dmai_attr.dma_attr_addr_lo,
                    (void *)(mp->dmai_attr.dma_attr_addr_hi + 1),
                    sleep);
#ifdef  PX_DMA_PROF
                px_dvma_vmem_xalloc++;
#endif  /* PX_DMA_PROF */
        }
        dvma_pg = MMU_BTOP((ulong_t)dvma_addr);
        dvma_pg_index = dvma_pg - mmu_p->dvma_base_pg;
        DBG(DBG_DMA_MAP, dip, "fallback dvma_pages: dvma_pg=%x index=%x\n",
            dvma_pg, dvma_pg_index);
        if (dvma_pg == 0)
                goto noresource;

        mp->dmai_mapping = mp->dmai_roffset | MMU_PTOB(dvma_pg);
        mp->dmai_offset = 0;
        PX_SAVE_MP_TTE(mp, attr);       /* mp->dmai_tte = tte */

        if ((ret = px_mmu_map_pages(mmu_p,
            mp, dvma_pg, npages, 0)) != DDI_SUCCESS) {
                if (mp->dmai_flags & PX_DMAI_FLAGS_VMEMCACHE) {
                        vmem_free(mmu_p->mmu_dvma_map, (void *)dvma_addr,
                            MMU_PAGE_SIZE);
#ifdef PX_DMA_PROF
                        px_dvma_vmem_free++;
#endif /* PX_DMA_PROF */
                } else {
                        vmem_xfree(mmu_p->mmu_dvma_map, (void *)dvma_addr,
                            MMU_PTOB(npages + PX_HAS_REDZONE(mp)));
#ifdef PX_DMA_PROF
                        px_dvma_vmem_xfree++;
#endif /* PX_DMA_PROF */
                }
        }

        return (ret);
noresource:
        if (dmareq->dmar_fp != DDI_DMA_DONTWAIT) {
                DBG(DBG_DMA_MAP, dip, "dvma_pg 0 - set callback\n");
                ddi_set_callback(dmareq->dmar_fp, dmareq->dmar_arg,
                    &mmu_p->mmu_dvma_clid);
        }
        DBG(DBG_DMA_MAP, dip, "vmem_xalloc - DDI_DMA_NORESOURCES\n");
        return (DDI_DMA_NORESOURCES);
}

void
px_dvma_unmap(px_mmu_t *mmu_p, ddi_dma_impl_t *mp)
{
        px_dvma_addr_t dvma_addr = (px_dvma_addr_t)mp->dmai_mapping;
        px_dvma_addr_t dvma_pg = MMU_BTOP(dvma_addr);
        dvma_addr = MMU_PTOB(dvma_pg);

        if (mp->dmai_flags & PX_DMAI_FLAGS_FASTTRACK) {
                px_iopfn_t index = dvma_pg - mmu_p->dvma_base_pg;
                ASSERT(index % px_dvma_page_cache_clustsz == 0);
                index /= px_dvma_page_cache_clustsz;
                ASSERT(index < px_dvma_page_cache_entries);
                mmu_p->mmu_dvma_cache_locks[index] = 0;
#ifdef  PX_DMA_PROF
                px_dvmaft_free++;
#endif  /* PX_DMA_PROF */
                return;
        }

        if (mp->dmai_flags & PX_DMAI_FLAGS_VMEMCACHE) {
                vmem_free(mmu_p->mmu_dvma_map, (void *)dvma_addr,
                    MMU_PAGE_SIZE);
#ifdef PX_DMA_PROF
                px_dvma_vmem_free++;
#endif /* PX_DMA_PROF */
        } else {
                size_t npages = MMU_BTOP(mp->dmai_winsize) + PX_HAS_REDZONE(mp);
                vmem_xfree(mmu_p->mmu_dvma_map, (void *)dvma_addr,
                    MMU_PTOB(npages));
#ifdef PX_DMA_PROF
                px_dvma_vmem_xfree++;
#endif /* PX_DMA_PROF */
        }
}

/*
 * DVMA mappings may have multiple windows, but each window always have
 * one segment.
 */
int
px_dvma_ctl(dev_info_t *dip, dev_info_t *rdip, ddi_dma_impl_t *mp,
        enum ddi_dma_ctlops cmd, off_t *offp, size_t *lenp, caddr_t *objp,
        uint_t cache_flags)
{
        switch (cmd) {
        default:
                DBG(DBG_DMA_CTL, dip, "unknown command (%x): rdip=%s%d\n",
                    cmd, ddi_driver_name(rdip), ddi_get_instance(rdip));
                break;
        }
        return (DDI_FAILURE);
}

void
px_dma_freewin(ddi_dma_impl_t *mp)
{
        px_dma_win_t *win_p = mp->dmai_winlst, *win2_p;
        for (win2_p = win_p; win_p; win2_p = win_p) {
                win_p = win2_p->win_next;
                kmem_free(win2_p, sizeof (px_dma_win_t) +
                    sizeof (ddi_dma_cookie_t) * win2_p->win_ncookies);
        }
        mp->dmai_nwin = 0;
        mp->dmai_winlst = NULL;
}

/*
 * px_dma_newwin - create a dma window object and cookies
 *
 *      After the initial scan in px_dma_physwin(), which identifies
 *      a portion of the pfn array that belongs to a dma window,
 *      we are called to allocate and initialize representing memory
 *      resources. We know from the 1st scan the number of cookies
 *      or dma segment in this window so we can allocate a contiguous
 *      memory array for the dma cookies (The implementation of
 *      ddi_dma_nextcookie(9f) dictates dma cookies be contiguous).
 *
 *      A second round scan is done on the pfn array to identify
 *      each dma segment and initialize its corresponding dma cookie.
 *      We don't need to do all the safety checking and we know they
 *      all belong to the same dma window.
 *
 *      Input:  cookie_no - # of cookies identified by the 1st scan
 *              start_idx - subscript of the pfn array for the starting pfn
 *              end_idx   - subscript of the last pfn in dma window
 *              win_pp    - pointer to win_next member of previous window
 *      Return: DDI_SUCCESS - with **win_pp as newly created window object
 *              DDI_DMA_NORESROUCE - caller frees all previous window objs
 *      Note:   Each cookie and window size are all initialized on page
 *              boundary. This is not true for the 1st cookie of the 1st
 *              window and the last cookie of the last window.
 *              We fix that later in upper layer which has access to size
 *              and offset info.
 *
 */
/*ARGSUSED*/
static int
px_dma_newwin(dev_info_t *dip, ddi_dma_req_t *dmareq, ddi_dma_impl_t *mp,
        uint32_t cookie_no, uint32_t start_idx, uint32_t end_idx,
        px_dma_win_t **win_pp, uint64_t count_max, uint64_t bypass)
{
        int (*waitfp)(caddr_t) = dmareq->dmar_fp;
        ddi_dma_cookie_t *cookie_p;
        uint32_t pfn_no = 1;
        px_iopfn_t pfn = PX_GET_MP_PFN(mp, start_idx);
        px_iopfn_t prev_pfn = pfn;
        uint64_t baddr, seg_pfn0 = pfn;
        size_t sz = cookie_no * sizeof (ddi_dma_cookie_t);
        px_dma_win_t *win_p = kmem_zalloc(sizeof (px_dma_win_t) + sz,
            waitfp == DDI_DMA_SLEEP ? KM_SLEEP : KM_NOSLEEP);
        io_attributes_t attr = PX_GET_TTE_ATTR(mp->dmai_rflags,
            mp->dmai_attr.dma_attr_flags);

        if (!win_p)
                goto noresource;

        win_p->win_next = NULL;
        win_p->win_ncookies = cookie_no;
        win_p->win_curseg = 0;  /* start from segment 0 */
        win_p->win_size = MMU_PTOB(end_idx - start_idx + 1);
        /* win_p->win_offset is left uninitialized */

        cookie_p = (ddi_dma_cookie_t *)(win_p + 1);
        start_idx++;
        for (; start_idx <= end_idx; start_idx++, prev_pfn = pfn, pfn_no++) {
                pfn = PX_GET_MP_PFN1(mp, start_idx);
                if ((pfn == prev_pfn + 1) &&
                    (MMU_PTOB(pfn_no + 1) - 1 <= count_max))
                        continue;

                /* close up the cookie up to (including) prev_pfn */
                baddr = MMU_PTOB(seg_pfn0);
                if (bypass) {
                        if (px_lib_iommu_getbypass(dip, baddr, attr, &baddr)
                            == DDI_SUCCESS)
                                baddr = px_lib_ro_bypass(dip, attr, baddr);
                        else
                                return (DDI_FAILURE);
                }

                MAKE_DMA_COOKIE(cookie_p, baddr, MMU_PTOB(pfn_no));
                DBG(DBG_BYPASS, mp->dmai_rdip, "cookie %p (%x pages)\n",
                    MMU_PTOB(seg_pfn0), pfn_no);

                cookie_p++;     /* advance to next available cookie cell */
                pfn_no = 0;
                seg_pfn0 = pfn; /* start a new segment from current pfn */
        }

        baddr = MMU_PTOB(seg_pfn0);
        if (bypass) {
                if (px_lib_iommu_getbypass(dip, baddr, attr, &baddr)
                    == DDI_SUCCESS)
                        baddr = px_lib_ro_bypass(dip, attr, baddr);
                else
                        return (DDI_FAILURE);
        }

        MAKE_DMA_COOKIE(cookie_p, baddr, MMU_PTOB(pfn_no));
        DBG(DBG_BYPASS, mp->dmai_rdip, "cookie %p (%x pages) of total %x\n",
            MMU_PTOB(seg_pfn0), pfn_no, cookie_no);
#ifdef  DEBUG
        cookie_p++;
        ASSERT((cookie_p - (ddi_dma_cookie_t *)(win_p + 1)) == cookie_no);
#endif  /* DEBUG */
        *win_pp = win_p;
        return (DDI_SUCCESS);
noresource:
        if (waitfp != DDI_DMA_DONTWAIT)
                ddi_set_callback(waitfp, dmareq->dmar_arg, &px_kmem_clid);
        return (DDI_DMA_NORESOURCES);
}

/*
 * px_dma_adjust - adjust 1st and last cookie and window sizes
 *      remove initial dma page offset from 1st cookie and window size
 *      remove last dma page remainder from last cookie and window size
 *      fill win_offset of each dma window according to just fixed up
 *              each window sizes
 *      px_dma_win_t members modified:
 *      win_p->win_offset - this window's offset within entire DMA object
 *      win_p->win_size   - xferrable size (in bytes) for this window
 *
 *      ddi_dma_impl_t members modified:
 *      mp->dmai_size     - 1st window xferrable size
 *      mp->dmai_offset   - 0, which is the dma offset of the 1st window
 *
 *      ddi_dma_cookie_t members modified:
 *      cookie_p->dmac_size - 1st and last cookie remove offset or remainder
 *      cookie_p->dmac_laddress - 1st cookie add page offset
 */
static void
px_dma_adjust(ddi_dma_req_t *dmareq, ddi_dma_impl_t *mp, px_dma_win_t *win_p)
{
        ddi_dma_cookie_t *cookie_p = (ddi_dma_cookie_t *)(win_p + 1);
        size_t pg_offset = mp->dmai_roffset;
        size_t win_offset = 0;

        cookie_p->dmac_size -= pg_offset;
        cookie_p->dmac_laddress |= pg_offset;
        win_p->win_size -= pg_offset;
        DBG(DBG_BYPASS, mp->dmai_rdip, "pg0 adjust %lx\n", pg_offset);

        mp->dmai_size = win_p->win_size;
        mp->dmai_offset = 0;

        pg_offset += mp->dmai_object.dmao_size;
        pg_offset &= MMU_PAGE_OFFSET;
        if (pg_offset)
                pg_offset = MMU_PAGE_SIZE - pg_offset;
        DBG(DBG_BYPASS, mp->dmai_rdip, "last pg adjust %lx\n", pg_offset);

        for (; win_p->win_next; win_p = win_p->win_next) {
                DBG(DBG_BYPASS, mp->dmai_rdip, "win off %p\n", win_offset);
                win_p->win_offset = win_offset;
                win_offset += win_p->win_size;
        }
        /* last window */
        win_p->win_offset = win_offset;
        cookie_p = (ddi_dma_cookie_t *)(win_p + 1);
        cookie_p[win_p->win_ncookies - 1].dmac_size -= pg_offset;
        win_p->win_size -= pg_offset;
        ASSERT((win_offset + win_p->win_size) == mp->dmai_object.dmao_size);
}

/*
 * px_dma_physwin() - carve up dma windows using physical addresses.
 *      Called to handle mmu bypass and pci peer-to-peer transfers.
 *      Calls px_dma_newwin() to allocate window objects.
 *
 * Dependency: mp->dmai_pfnlst points to an array of pfns
 *
 * 1. Each dma window is represented by a px_dma_win_t object.
 *      The object will be casted to ddi_dma_win_t and returned
 *      to leaf driver through the DDI interface.
 * 2. Each dma window can have several dma segments with each
 *      segment representing a physically contiguous either memory
 *      space (if we are doing an mmu bypass transfer) or pci address
 *      space (if we are doing a peer-to-peer transfer).
 * 3. Each segment has a DMA cookie to program the DMA engine.
 *      The cookies within each DMA window must be located in a
 *      contiguous array per ddi_dma_nextcookie(9f).
 * 4. The number of DMA segments within each DMA window cannot exceed
 *      mp->dmai_attr.dma_attr_sgllen. If the transfer size is
 *      too large to fit in the sgllen, the rest needs to be
 *      relocated to the next dma window.
 * 5. Peer-to-peer DMA segment follows device hi, lo, count_max,
 *      and nocross restrictions while bypass DMA follows the set of
 *      restrictions with system limits factored in.
 *
 * Return:
 *      mp->dmai_winlst  - points to a link list of px_dma_win_t objects.
 *              Each px_dma_win_t object on the link list contains
 *              infomation such as its window size (# of pages),
 *              starting offset (also see Restriction), an array of
 *              DMA cookies, and # of cookies in the array.
 *      mp->dmai_pfnlst  - NULL, the pfn list is freed to conserve memory.
 *      mp->dmai_nwin    - # of total DMA windows on mp->dmai_winlst.
 *      mp->dmai_mapping - starting cookie address
 *      mp->dmai_rflags  - consistent, nosync, no redzone
 *      mp->dmai_cookie  - start of cookie table of the 1st DMA window
 *
 * Restriction:
 *      Each px_dma_win_t object can theoratically start from any offset
 *      since the mmu is not involved. However, this implementation
 *      always make windows start from page aligned offset (except
 *      the 1st window, which follows the requested offset) due to the
 *      fact that we are handed a pfn list. This does require device's
 *      count_max and attr_seg to be at least MMU_PAGE_SIZE aligned.
 */
int
px_dma_physwin(px_t *px_p, ddi_dma_req_t *dmareq, ddi_dma_impl_t *mp)
{
        uint_t npages = mp->dmai_ndvmapages;
        int ret, sgllen = mp->dmai_attr.dma_attr_sgllen;
        px_iopfn_t pfn_lo, pfn_hi, prev_pfn;
        px_iopfn_t pfn = PX_GET_MP_PFN(mp, 0);
        uint32_t i, win_no = 0, pfn_no = 1, win_pfn0_index = 0, cookie_no = 0;
        uint64_t count_max, bypass_addr = 0;
        px_dma_win_t **win_pp = (px_dma_win_t **)&mp->dmai_winlst;
        ddi_dma_cookie_t *cookie0_p;
        io_attributes_t attr = PX_GET_TTE_ATTR(mp->dmai_rflags,
            mp->dmai_attr.dma_attr_flags);
        dev_info_t *dip = px_p->px_dip;

        ASSERT(PX_DMA_ISPTP(mp) || PX_DMA_ISBYPASS(mp));
        if (PX_DMA_ISPTP(mp)) { /* ignore sys limits for peer-to-peer */
                ddi_dma_attr_t *dev_attr_p = PX_DEV_ATTR(mp);
                uint64_t nocross = dev_attr_p->dma_attr_seg;
                px_pec_t *pec_p = px_p->px_pec_p;
                px_iopfn_t pfn_last = PX_DMA_ISPTP32(mp) ?
                    pec_p->pec_last32_pfn - pec_p->pec_base32_pfn :
                    pec_p->pec_last64_pfn - pec_p->pec_base64_pfn;

                if (nocross && (nocross < UINT32_MAX))
                        return (DDI_DMA_NOMAPPING);
                if (dev_attr_p->dma_attr_align > MMU_PAGE_SIZE)
                        return (DDI_DMA_NOMAPPING);
                pfn_lo = MMU_BTOP(dev_attr_p->dma_attr_addr_lo);
                pfn_hi = MMU_BTOP(dev_attr_p->dma_attr_addr_hi);
                pfn_hi = MIN(pfn_hi, pfn_last);
                if ((pfn_lo > pfn_hi) || (pfn < pfn_lo))
                        return (DDI_DMA_NOMAPPING);

                count_max = dev_attr_p->dma_attr_count_max;
                count_max = MIN(count_max, nocross);
                /*
                 * the following count_max trim is not done because we are
                 * making sure pfn_lo <= pfn <= pfn_hi inside the loop
                 * count_max=MIN(count_max, MMU_PTOB(pfn_hi - pfn_lo + 1)-1);
                 */
        } else { /* bypass hi/lo/count_max have been processed by attr2hdl() */
                count_max = mp->dmai_attr.dma_attr_count_max;
                pfn_lo = MMU_BTOP(mp->dmai_attr.dma_attr_addr_lo);
                pfn_hi = MMU_BTOP(mp->dmai_attr.dma_attr_addr_hi);

                if (px_lib_iommu_getbypass(dip, MMU_PTOB(pfn),
                    attr, &bypass_addr) != DDI_SUCCESS) {
                        DBG(DBG_BYPASS, mp->dmai_rdip,
                            "bypass cookie failure %lx\n", pfn);
                        return (DDI_DMA_NOMAPPING);
                }
                pfn = MMU_BTOP(bypass_addr);
        }

        /* pfn: absolute (bypass mode) or relative (p2p mode) */
        for (prev_pfn = pfn, i = 1; i < npages;
            i++, prev_pfn = pfn, pfn_no++) {
                pfn = PX_GET_MP_PFN1(mp, i);
                if (bypass_addr) {
                        if (px_lib_iommu_getbypass(dip, MMU_PTOB(pfn), attr,
                            &bypass_addr) != DDI_SUCCESS) {
                                ret = DDI_DMA_NOMAPPING;
                                goto err;
                        }
                        pfn = MMU_BTOP(bypass_addr);
                }
                if ((pfn == prev_pfn + 1) &&
                    (MMU_PTOB(pfn_no + 1) - 1 <= count_max))
                        continue;
                if ((pfn < pfn_lo) || (prev_pfn > pfn_hi)) {
                        ret = DDI_DMA_NOMAPPING;
                        goto err;
                }
                cookie_no++;
                pfn_no = 0;
                if (cookie_no < sgllen)
                        continue;

                DBG(DBG_BYPASS, mp->dmai_rdip, "newwin pfn[%x-%x] %x cks\n",
                    win_pfn0_index, i - 1, cookie_no);
                if (ret = px_dma_newwin(dip, dmareq, mp, cookie_no,
                    win_pfn0_index, i - 1, win_pp, count_max, bypass_addr))
                        goto err;

                win_pp = &(*win_pp)->win_next;  /* win_pp = *(win_pp) */
                win_no++;
                win_pfn0_index = i;
                cookie_no = 0;
        }
        if (pfn > pfn_hi) {
                ret = DDI_DMA_NOMAPPING;
                goto err;
        }
        cookie_no++;
        DBG(DBG_BYPASS, mp->dmai_rdip, "newwin pfn[%x-%x] %x cks\n",
            win_pfn0_index, i - 1, cookie_no);
        if (ret = px_dma_newwin(dip, dmareq, mp, cookie_no, win_pfn0_index,
            i - 1, win_pp, count_max, bypass_addr))
                goto err;
        win_no++;
        px_dma_adjust(dmareq, mp, mp->dmai_winlst);
        mp->dmai_nwin = win_no;
        mp->dmai_rflags |= DDI_DMA_CONSISTENT | DMP_NOSYNC;
        mp->dmai_rflags &= ~DDI_DMA_REDZONE;
        mp->dmai_flags |= PX_DMAI_FLAGS_NOSYNC;
        cookie0_p = (ddi_dma_cookie_t *)(PX_WINLST(mp) + 1);
        mp->dmai_cookie = PX_WINLST(mp)->win_ncookies > 1 ? cookie0_p + 1 : 0;
        mp->dmai_mapping = cookie0_p->dmac_laddress;

        px_dma_freepfn(mp);
        return (DDI_DMA_MAPPED);
err:
        px_dma_freewin(mp);
        return (ret);
}

int
px_dma_ctl(dev_info_t *dip, dev_info_t *rdip, ddi_dma_impl_t *mp,
        enum ddi_dma_ctlops cmd, off_t *offp, size_t *lenp, caddr_t *objp,
        uint_t cache_flags)
{
        switch (cmd) {
        default:
                DBG(DBG_DMA_CTL, dip, "unknown command (%x): rdip=%s%d\n",
                    cmd, ddi_driver_name(rdip), ddi_get_instance(rdip));
                break;
        }
        return (DDI_FAILURE);
}

static void
px_dvma_debug_init(px_mmu_t *mmu_p)
{
        size_t sz = sizeof (struct px_dvma_rec) * px_dvma_debug_rec;
        ASSERT(MUTEX_HELD(&mmu_p->dvma_debug_lock));
        cmn_err(CE_NOTE, "PCI Express DVMA %p stat ON", mmu_p);

        mmu_p->dvma_alloc_rec = kmem_alloc(sz, KM_SLEEP);
        mmu_p->dvma_free_rec = kmem_alloc(sz, KM_SLEEP);

        mmu_p->dvma_active_list = NULL;
        mmu_p->dvma_alloc_rec_index = 0;
        mmu_p->dvma_free_rec_index = 0;
        mmu_p->dvma_active_count = 0;
}

void
px_dvma_debug_fini(px_mmu_t *mmu_p)
{
        struct px_dvma_rec *prev, *ptr;
        size_t sz = sizeof (struct px_dvma_rec) * px_dvma_debug_rec;
        uint64_t mask = ~(1ull << mmu_p->mmu_inst);
        cmn_err(CE_NOTE, "PCI Express DVMA %p stat OFF", mmu_p);

        if (mmu_p->dvma_alloc_rec) {
                kmem_free(mmu_p->dvma_alloc_rec, sz);
                mmu_p->dvma_alloc_rec = NULL;
        }
        if (mmu_p->dvma_free_rec) {
                kmem_free(mmu_p->dvma_free_rec, sz);
                mmu_p->dvma_free_rec = NULL;
        }

        prev = mmu_p->dvma_active_list;
        if (!prev)
                return;
        for (ptr = prev->next; ptr; prev = ptr, ptr = ptr->next)
                kmem_free(prev, sizeof (struct px_dvma_rec));
        kmem_free(prev, sizeof (struct px_dvma_rec));

        mmu_p->dvma_active_list = NULL;
        mmu_p->dvma_alloc_rec_index = 0;
        mmu_p->dvma_free_rec_index = 0;
        mmu_p->dvma_active_count = 0;

        px_dvma_debug_off &= mask;
        px_dvma_debug_on &= mask;
}

void
px_dvma_alloc_debug(px_mmu_t *mmu_p, char *address, uint_t len,
        ddi_dma_impl_t *mp)
{
        struct px_dvma_rec *ptr;
        mutex_enter(&mmu_p->dvma_debug_lock);

        if (!mmu_p->dvma_alloc_rec)
                px_dvma_debug_init(mmu_p);
        if (PX_DVMA_DBG_OFF(mmu_p)) {
                px_dvma_debug_fini(mmu_p);
                goto done;
        }

        ptr = &mmu_p->dvma_alloc_rec[mmu_p->dvma_alloc_rec_index];
        ptr->dvma_addr = address;
        ptr->len = len;
        ptr->mp = mp;
        if (++mmu_p->dvma_alloc_rec_index == px_dvma_debug_rec)
                mmu_p->dvma_alloc_rec_index = 0;

        ptr = kmem_alloc(sizeof (struct px_dvma_rec), KM_SLEEP);
        ptr->dvma_addr = address;
        ptr->len = len;
        ptr->mp = mp;

        ptr->next = mmu_p->dvma_active_list;
        mmu_p->dvma_active_list = ptr;
        mmu_p->dvma_active_count++;
done:
        mutex_exit(&mmu_p->dvma_debug_lock);
}

void
px_dvma_free_debug(px_mmu_t *mmu_p, char *address, uint_t len,
    ddi_dma_impl_t *mp)
{
        struct px_dvma_rec *ptr, *ptr_save;
        mutex_enter(&mmu_p->dvma_debug_lock);

        if (!mmu_p->dvma_alloc_rec)
                px_dvma_debug_init(mmu_p);
        if (PX_DVMA_DBG_OFF(mmu_p)) {
                px_dvma_debug_fini(mmu_p);
                goto done;
        }

        ptr = &mmu_p->dvma_free_rec[mmu_p->dvma_free_rec_index];
        ptr->dvma_addr = address;
        ptr->len = len;
        ptr->mp = mp;
        if (++mmu_p->dvma_free_rec_index == px_dvma_debug_rec)
                mmu_p->dvma_free_rec_index = 0;

        ptr_save = mmu_p->dvma_active_list;
        for (ptr = ptr_save; ptr; ptr = ptr->next) {
                if ((ptr->dvma_addr == address) && (ptr->len = len))
                        break;
                ptr_save = ptr;
        }
        if (!ptr) {
                cmn_err(CE_WARN, "bad dvma free addr=%lx len=%x",
                    (long)address, len);
                goto done;
        }
        if (ptr == mmu_p->dvma_active_list)
                mmu_p->dvma_active_list = ptr->next;
        else
                ptr_save->next = ptr->next;
        kmem_free(ptr, sizeof (struct px_dvma_rec));
        mmu_p->dvma_active_count--;
done:
        mutex_exit(&mmu_p->dvma_debug_lock);
}

#ifdef  DEBUG
void
px_dump_dma_handle(uint64_t flag, dev_info_t *dip, ddi_dma_impl_t *hp)
{
        DBG(flag, dip, "mp(%p): flags=%x mapping=%lx xfer_size=%x\n",
            hp, hp->dmai_inuse, hp->dmai_mapping, hp->dmai_size);
        DBG(flag|DBG_CONT, dip, "\tnpages=%x roffset=%x rflags=%x nwin=%x\n",
            hp->dmai_ndvmapages, hp->dmai_roffset, hp->dmai_rflags,
            hp->dmai_nwin);
        DBG(flag|DBG_CONT, dip, "\twinsize=%x tte=%p pfnlst=%p pfn0=%p\n",
            hp->dmai_winsize, hp->dmai_tte, hp->dmai_pfnlst, hp->dmai_pfn0);
        DBG(flag|DBG_CONT, dip, "\twinlst=%x obj=%p attr=%p ckp=%p\n",
            hp->dmai_winlst, &hp->dmai_object, &hp->dmai_attr,
            hp->dmai_cookie);
}
#endif  /* DEBUG */