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dwlpx_dma.c revision 1.19
      1  1.19      dsl /* $NetBSD: dwlpx_dma.c,v 1.19 2009/03/14 15:35:59 dsl Exp $ */
      2   1.2  thorpej 
      3   1.2  thorpej /*-
      4   1.5  thorpej  * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
      5   1.2  thorpej  * All rights reserved.
      6   1.2  thorpej  *
      7   1.2  thorpej  * This code is derived from software contributed to The NetBSD Foundation
      8   1.2  thorpej  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9   1.2  thorpej  * NASA Ames Research Center.
     10   1.2  thorpej  *
     11   1.2  thorpej  * Redistribution and use in source and binary forms, with or without
     12   1.2  thorpej  * modification, are permitted provided that the following conditions
     13   1.2  thorpej  * are met:
     14   1.2  thorpej  * 1. Redistributions of source code must retain the above copyright
     15   1.2  thorpej  *    notice, this list of conditions and the following disclaimer.
     16   1.2  thorpej  * 2. Redistributions in binary form must reproduce the above copyright
     17   1.2  thorpej  *    notice, this list of conditions and the following disclaimer in the
     18   1.2  thorpej  *    documentation and/or other materials provided with the distribution.
     19   1.2  thorpej  *
     20   1.2  thorpej  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21   1.2  thorpej  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22   1.2  thorpej  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23   1.2  thorpej  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24  1.13       pk  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25   1.2  thorpej  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26   1.2  thorpej  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27   1.2  thorpej  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28   1.2  thorpej  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29   1.2  thorpej  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30   1.2  thorpej  * POSSIBILITY OF SUCH DAMAGE.
     31   1.2  thorpej  */
     32   1.2  thorpej 
     33   1.2  thorpej #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
     34   1.2  thorpej 
     35  1.19      dsl __KERNEL_RCSID(0, "$NetBSD: dwlpx_dma.c,v 1.19 2009/03/14 15:35:59 dsl Exp $");
     36   1.2  thorpej 
     37   1.2  thorpej #include <sys/param.h>
     38   1.2  thorpej #include <sys/systm.h>
     39   1.2  thorpej #include <sys/kernel.h>
     40   1.2  thorpej #include <sys/device.h>
     41   1.2  thorpej #include <sys/malloc.h>
     42  1.14      mrg 
     43  1.14      mrg #include <uvm/uvm_extern.h>
     44   1.2  thorpej 
     45   1.2  thorpej #define _ALPHA_BUS_DMA_PRIVATE
     46   1.2  thorpej #include <machine/bus.h>
     47   1.2  thorpej 
     48   1.2  thorpej #include <dev/pci/pcireg.h>
     49   1.2  thorpej #include <dev/pci/pcivar.h>
     50   1.2  thorpej #include <alpha/tlsb/tlsbreg.h>
     51   1.2  thorpej #include <alpha/tlsb/kftxxvar.h>
     52   1.2  thorpej #include <alpha/tlsb/kftxxreg.h>
     53   1.2  thorpej #include <alpha/pci/dwlpxreg.h>
     54   1.2  thorpej #include <alpha/pci/dwlpxvar.h>
     55   1.2  thorpej #include <alpha/pci/pci_kn8ae.h>
     56   1.2  thorpej 
     57  1.18      dsl bus_dma_tag_t dwlpx_dma_get_tag(bus_dma_tag_t, alpha_bus_t);
     58   1.2  thorpej 
     59  1.18      dsl int	dwlpx_bus_dmamap_load_sgmap(bus_dma_tag_t, bus_dmamap_t, void *,
     60  1.18      dsl 	    bus_size_t, struct proc *, int);
     61   1.2  thorpej 
     62  1.18      dsl int	dwlpx_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t, bus_dmamap_t,
     63  1.18      dsl 	    struct mbuf *, int);
     64   1.2  thorpej 
     65  1.18      dsl int	dwlpx_bus_dmamap_load_uio_sgmap(bus_dma_tag_t, bus_dmamap_t,
     66  1.18      dsl 	    struct uio *, int);
     67   1.2  thorpej 
     68  1.18      dsl int	dwlpx_bus_dmamap_load_raw_sgmap(bus_dma_tag_t, bus_dmamap_t,
     69  1.18      dsl 	    bus_dma_segment_t *, int, bus_size_t, int);
     70   1.2  thorpej 
     71  1.18      dsl void	dwlpx_bus_dmamap_unload_sgmap(bus_dma_tag_t, bus_dmamap_t);
     72   1.2  thorpej 
     73   1.9  thorpej /*
     74   1.9  thorpej  * Direct-mapped window: 2G at 2G
     75   1.9  thorpej  */
     76   1.9  thorpej #define	DWLPx_DIRECT_MAPPED_BASE	(2UL*1024UL*1024UL*1024UL)
     77   1.9  thorpej #define	DWLPx_DIRECT_MAPPED_SIZE	(2UL*1024UL*1024UL*1024UL)
     78   1.9  thorpej 
     79   1.9  thorpej /*
     80   1.9  thorpej  * SGMAP window A: 256M or 1G at 1G
     81   1.9  thorpej  */
     82   1.9  thorpej #define	DWLPx_SG_MAPPED_BASE		(1*1024*1024*1024)
     83   1.9  thorpej #define	DWLPx_SG_MAPPED_SIZE(x)		((x) * PAGE_SIZE)
     84   1.9  thorpej 
     85  1.16  thorpej /* DWLPx has a 256-byte out-bound DMA prefetch threshold. */
     86  1.16  thorpej #define	DWLPx_SG_MAPPED_PFTHRESH	256
     87  1.16  thorpej 
     88   1.9  thorpej /*
     89   1.9  thorpej  * Set this to always use SGMAPs.
     90   1.9  thorpej  */
     91   1.9  thorpej #ifdef DWLPX_ALWAYS_USE_SGMAP
     92   1.9  thorpej int	dwlpx_always_use_sgmap = 1;
     93   1.9  thorpej #else
     94   1.9  thorpej int	dwlpx_always_use_sgmap = 0;
     95   1.9  thorpej #endif
     96   1.2  thorpej 
     97   1.2  thorpej void
     98  1.19      dsl dwlpx_dma_init(struct dwlpx_config *ccp)
     99   1.2  thorpej {
    100   1.2  thorpej 	char *exname;
    101   1.2  thorpej 	bus_dma_tag_t t;
    102   1.2  thorpej 	u_int32_t *page_table;
    103   1.7   mjacob 	int i, lim, wmask;
    104   1.2  thorpej 
    105   1.2  thorpej 	/*
    106   1.9  thorpej 	 * Determine size of Window C based on the amount of SGMAP
    107   1.9  thorpej 	 * page table SRAM available.
    108   1.9  thorpej 	 */
    109   1.9  thorpej 	if (ccp->cc_sc->dwlpx_sgmapsz == DWLPX_SG128K) {
    110   1.9  thorpej 		lim = 128 * 1024;
    111   1.9  thorpej 		wmask = PCIA_WMASK_1G;
    112   1.9  thorpej 	} else {
    113   1.9  thorpej 		lim = 32 * 1024;
    114   1.9  thorpej 		wmask = PCIA_WMASK_256M;
    115   1.9  thorpej 	}
    116   1.9  thorpej 
    117   1.9  thorpej 	/*
    118   1.9  thorpej 	 * Initialize the DMA tag used for direct-mapped DMA.  Chain
    119   1.9  thorpej 	 * this window to the SGMAP window, because we might have
    120   1.9  thorpej 	 * a lot of memory in the machine.
    121   1.2  thorpej 	 */
    122   1.2  thorpej 	t = &ccp->cc_dmat_direct;
    123   1.2  thorpej 	t->_cookie = ccp;
    124   1.8  thorpej 	t->_wbase = DWLPx_DIRECT_MAPPED_BASE;
    125   1.9  thorpej 	t->_wsize = DWLPx_DIRECT_MAPPED_SIZE;
    126   1.9  thorpej 	t->_next_window = &ccp->cc_dmat_sgmap;
    127  1.10  thorpej 	t->_boundary = 0;
    128   1.9  thorpej 	t->_sgmap = NULL;
    129   1.2  thorpej 	t->_get_tag = dwlpx_dma_get_tag;
    130   1.2  thorpej 	t->_dmamap_create = _bus_dmamap_create;
    131   1.2  thorpej 	t->_dmamap_destroy = _bus_dmamap_destroy;
    132   1.8  thorpej 	t->_dmamap_load = _bus_dmamap_load_direct;
    133   1.8  thorpej 	t->_dmamap_load_mbuf = _bus_dmamap_load_mbuf_direct;
    134   1.8  thorpej 	t->_dmamap_load_uio = _bus_dmamap_load_uio_direct;
    135   1.8  thorpej 	t->_dmamap_load_raw = _bus_dmamap_load_raw_direct;
    136   1.2  thorpej 	t->_dmamap_unload = _bus_dmamap_unload;
    137   1.6  thorpej 	t->_dmamap_sync = _bus_dmamap_sync;
    138   1.2  thorpej 
    139   1.2  thorpej 	t->_dmamem_alloc = _bus_dmamem_alloc;
    140   1.2  thorpej 	t->_dmamem_free = _bus_dmamem_free;
    141   1.2  thorpej 	t->_dmamem_map = _bus_dmamem_map;
    142   1.2  thorpej 	t->_dmamem_unmap = _bus_dmamem_unmap;
    143   1.2  thorpej 	t->_dmamem_mmap = _bus_dmamem_mmap;
    144   1.2  thorpej 
    145   1.2  thorpej 	/*
    146   1.2  thorpej 	 * Initialize the DMA tag used for sgmap-mapped DMA.
    147   1.2  thorpej 	 */
    148   1.2  thorpej 	t = &ccp->cc_dmat_sgmap;
    149   1.2  thorpej 	t->_cookie = ccp;
    150   1.8  thorpej 	t->_wbase = DWLPx_SG_MAPPED_BASE;
    151   1.9  thorpej 	t->_wsize = DWLPx_SG_MAPPED_SIZE(lim);
    152   1.9  thorpej 	t->_next_window = NULL;
    153  1.10  thorpej 	t->_boundary = 0;
    154   1.9  thorpej 	t->_sgmap = &ccp->cc_sgmap;
    155  1.16  thorpej 	t->_pfthresh = DWLPx_SG_MAPPED_PFTHRESH;
    156   1.2  thorpej 	t->_get_tag = dwlpx_dma_get_tag;
    157  1.15  thorpej 	t->_dmamap_create = alpha_sgmap_dmamap_create;
    158  1.15  thorpej 	t->_dmamap_destroy = alpha_sgmap_dmamap_destroy;
    159   1.2  thorpej 	t->_dmamap_load = dwlpx_bus_dmamap_load_sgmap;
    160   1.2  thorpej 	t->_dmamap_load_mbuf = dwlpx_bus_dmamap_load_mbuf_sgmap;
    161   1.2  thorpej 	t->_dmamap_load_uio = dwlpx_bus_dmamap_load_uio_sgmap;
    162   1.2  thorpej 	t->_dmamap_load_raw = dwlpx_bus_dmamap_load_raw_sgmap;
    163   1.2  thorpej 	t->_dmamap_unload = dwlpx_bus_dmamap_unload_sgmap;
    164   1.6  thorpej 	t->_dmamap_sync = _bus_dmamap_sync;
    165   1.2  thorpej 
    166   1.2  thorpej 	t->_dmamem_alloc = _bus_dmamem_alloc;
    167   1.2  thorpej 	t->_dmamem_free = _bus_dmamem_free;
    168   1.2  thorpej 	t->_dmamem_map = _bus_dmamem_map;
    169   1.2  thorpej 	t->_dmamem_unmap = _bus_dmamem_unmap;
    170   1.2  thorpej 	t->_dmamem_mmap = _bus_dmamem_mmap;
    171   1.2  thorpej 
    172   1.2  thorpej 	/*
    173   1.2  thorpej 	 * A few notes about SGMAP-mapped DMA on the DWLPx:
    174   1.2  thorpej 	 *
    175   1.2  thorpej 	 * The DWLPx has PCIA-resident SRAM that is used for
    176   1.2  thorpej 	 * the SGMAP page table; there is no TLB.  The DWLPA
    177   1.2  thorpej 	 * has room for 32K entries, yielding a total of 256M
    178   1.2  thorpej 	 * of sgva space.  The DWLPB has 32K entries or 128K
    179   1.7   mjacob 	 * entries, depending on TBIT, yielding either 256M or
    180   1.2  thorpej 	 * 1G of sgva space.
    181   1.2  thorpej 	 *
    182   1.2  thorpej 	 * This sgva space must be shared across all windows
    183   1.2  thorpej 	 * that wish to use SGMAP-mapped DMA; make sure to
    184   1.2  thorpej 	 * adjust the "sgvabase" argument to alpha_sgmap_init()
    185   1.2  thorpej 	 * accordingly if you create more than one SGMAP-mapped
    186   1.2  thorpej 	 * window.  Note that sgvabase != window base.  The former
    187   1.2  thorpej 	 * is used to compute indexes into the page table only.
    188   1.2  thorpej 	 *
    189   1.7   mjacob 	 * In the current implementation the first window is a
    190   1.7   mjacob 	 * 2G window direct-mapped mapped at 2G and the second
    191   1.7   mjacob 	 * window is disabled and the third window is a 256M
    192   1.7   mjacob 	 * or 1GB scatter/gather map at 1GB.
    193   1.9  thorpej 	 *
    194   1.9  thorpej 	 * We just punt on trying to support ISA DMA.  If you want
    195   1.9  thorpej 	 * try that on a TurboLaser, well, you just lose.
    196   1.2  thorpej 	 */
    197   1.2  thorpej 
    198   1.2  thorpej 	/*
    199   1.2  thorpej 	 * Initialize the page table.
    200   1.2  thorpej 	 */
    201   1.2  thorpej 	page_table =
    202   1.2  thorpej 	    (u_int32_t *)ALPHA_PHYS_TO_K0SEG(PCIA_SGMAP_PT + ccp->cc_sysbase);
    203   1.7   mjacob 	for (i = 0; i < lim; i++)
    204   1.7   mjacob 		page_table[i * SGMAP_PTE_SPACING] = 0;
    205   1.2  thorpej 	alpha_mb();
    206   1.2  thorpej 
    207   1.2  thorpej 	/*
    208   1.7   mjacob 	 * Initialize the SGMAP for window C:
    209   1.2  thorpej 	 *
    210   1.7   mjacob 	 *	Size: 256M or 1GB
    211   1.7   mjacob 	 *	Window base: 1GB
    212   1.2  thorpej 	 *	SGVA base: 0
    213   1.2  thorpej 	 */
    214   1.2  thorpej 	exname = malloc(16, M_DEVBUF, M_NOWAIT);
    215   1.2  thorpej 	if (exname == NULL)
    216   1.2  thorpej 		panic("dwlpx_dma_init");
    217   1.2  thorpej 	sprintf(exname, "%s_sgmap_a", ccp->cc_sc->dwlpx_dev.dv_xname);
    218   1.7   mjacob 	alpha_sgmap_init(t, &ccp->cc_sgmap, exname, DWLPx_SG_MAPPED_BASE,
    219   1.9  thorpej 	    0, DWLPx_SG_MAPPED_SIZE(lim), sizeof(u_int32_t),
    220   1.9  thorpej 	    (void *)page_table, 0);
    221   1.2  thorpej 
    222   1.2  thorpej 	/*
    223   1.2  thorpej 	 * Set up DMA windows for this DWLPx.
    224   1.2  thorpej 	 *
    225   1.2  thorpej 	 * Do this even for all HPCs- even for the nonexistent
    226   1.2  thorpej 	 * one on hose zero of a KFTIA.
    227   1.2  thorpej 	 */
    228   1.2  thorpej 	for (i = 0; i < NHPC; i++) {
    229   1.7   mjacob 		REGVAL(PCIA_WMASK_A(i) + ccp->cc_sysbase) = PCIA_WMASK_2G;
    230   1.2  thorpej 		REGVAL(PCIA_TBASE_A(i) + ccp->cc_sysbase) = 0;
    231   1.2  thorpej 		REGVAL(PCIA_WBASE_A(i) + ccp->cc_sysbase) =
    232   1.7   mjacob 		    DWLPx_DIRECT_MAPPED_BASE | PCIA_WBASE_W_EN;
    233   1.2  thorpej 
    234   1.7   mjacob 		REGVAL(PCIA_WMASK_B(i) + ccp->cc_sysbase) = 0;
    235   1.2  thorpej 		REGVAL(PCIA_TBASE_B(i) + ccp->cc_sysbase) = 0;
    236   1.7   mjacob 		REGVAL(PCIA_WBASE_B(i) + ccp->cc_sysbase) = 0;
    237   1.2  thorpej 
    238   1.7   mjacob 		REGVAL(PCIA_WMASK_C(i) + ccp->cc_sysbase) = wmask;
    239   1.2  thorpej 		REGVAL(PCIA_TBASE_C(i) + ccp->cc_sysbase) = 0;
    240   1.7   mjacob 		REGVAL(PCIA_WBASE_C(i) + ccp->cc_sysbase) =
    241   1.7   mjacob 		    DWLPx_SG_MAPPED_BASE | PCIA_WBASE_W_EN | PCIA_WBASE_SG_EN;
    242   1.2  thorpej 		alpha_mb();
    243   1.2  thorpej 	}
    244   1.2  thorpej 
    245   1.2  thorpej 	/* XXX XXX BEGIN XXX XXX */
    246   1.2  thorpej 	{							/* XXX */
    247  1.11  thorpej 		extern paddr_t alpha_XXX_dmamap_or;		/* XXX */
    248   1.2  thorpej 		alpha_XXX_dmamap_or = DWLPx_DIRECT_MAPPED_BASE;	/* XXX */
    249   1.2  thorpej 	}							/* XXX */
    250   1.2  thorpej 	/* XXX XXX END XXX XXX */
    251   1.2  thorpej }
    252   1.2  thorpej 
    253   1.2  thorpej /*
    254   1.2  thorpej  * Return the bus dma tag to be used for the specified bus type.
    255   1.2  thorpej  * INTERNAL USE ONLY!
    256   1.2  thorpej  */
    257   1.2  thorpej bus_dma_tag_t
    258  1.19      dsl dwlpx_dma_get_tag(bus_dma_tag_t t, alpha_bus_t bustype)
    259   1.2  thorpej {
    260   1.2  thorpej 	struct dwlpx_config *ccp = t->_cookie;
    261   1.2  thorpej 
    262   1.2  thorpej 	switch (bustype) {
    263   1.2  thorpej 	case ALPHA_BUS_PCI:
    264   1.2  thorpej 	case ALPHA_BUS_EISA:
    265   1.9  thorpej 		if (dwlpx_always_use_sgmap) {
    266   1.9  thorpej 			/*
    267   1.9  thorpej 			 * Always use SGMAPs (for testing purposes?)
    268   1.9  thorpej 			 */
    269   1.9  thorpej 			return (&ccp->cc_dmat_sgmap);
    270   1.9  thorpej 		}
    271   1.2  thorpej 		/*
    272   1.9  thorpej 		 * Give these busses the direct-mapped window; if the
    273   1.9  thorpej 		 * address crosses the threshold, it will fall back
    274   1.9  thorpej 		 * onto the SGMAP window.
    275   1.2  thorpej 		 */
    276   1.9  thorpej 		return (&ccp->cc_dmat_direct);
    277   1.2  thorpej 
    278   1.2  thorpej 	case ALPHA_BUS_ISA:
    279   1.2  thorpej 		/*
    280   1.9  thorpej 		 * Don't even bother; it's not easy, given how the
    281   1.9  thorpej 		 * page table is arranged, and it's not really worth
    282   1.9  thorpej 		 * the trouble.
    283   1.2  thorpej 		 */
    284   1.9  thorpej 		panic("dwlpx_dma_get_tag: ISA DMA?  Forget it...");
    285   1.9  thorpej 		/* NOTREACHED */
    286   1.2  thorpej 
    287   1.2  thorpej 	default:
    288   1.2  thorpej 		panic("dwlpx_dma_get_tag: shouldn't be here, really...");
    289   1.2  thorpej 	}
    290   1.2  thorpej }
    291   1.2  thorpej 
    292   1.2  thorpej /*
    293   1.2  thorpej  * Load a DWLPx SGMAP-mapped DMA map with a linear buffer.
    294   1.2  thorpej  */
    295   1.2  thorpej int
    296  1.19      dsl dwlpx_bus_dmamap_load_sgmap(bus_dma_tag_t t, bus_dmamap_t map, void *buf, bus_size_t buflen, struct proc *p, int flags)
    297   1.2  thorpej {
    298   1.2  thorpej 
    299   1.2  thorpej 	return (pci_sgmap_pte32_load(t, map, buf, buflen, p, flags,
    300   1.9  thorpej 	    t->_sgmap));
    301   1.2  thorpej }
    302   1.2  thorpej 
    303   1.2  thorpej /*
    304   1.2  thorpej  * Load a DWLPx SGMAP-mapped DMA map with an mbuf chain.
    305   1.2  thorpej  */
    306   1.2  thorpej int
    307  1.19      dsl dwlpx_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m, int flags)
    308   1.2  thorpej {
    309   1.2  thorpej 
    310   1.9  thorpej 	return (pci_sgmap_pte32_load_mbuf(t, map, m, flags, t->_sgmap));
    311   1.2  thorpej }
    312   1.2  thorpej 
    313   1.2  thorpej /*
    314   1.2  thorpej  * Load a DWLPx SGMAP-mapped DMA map with a uio.
    315   1.2  thorpej  */
    316   1.2  thorpej int
    317  1.19      dsl dwlpx_bus_dmamap_load_uio_sgmap(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio, int flags)
    318   1.2  thorpej {
    319   1.2  thorpej 
    320   1.9  thorpej 	return (pci_sgmap_pte32_load_uio(t, map, uio, flags, t->_sgmap));
    321   1.2  thorpej }
    322   1.2  thorpej 
    323   1.2  thorpej /*
    324   1.2  thorpej  * Load a DWLPx SGMAP-mapped DMA map with raw memory.
    325   1.2  thorpej  */
    326   1.2  thorpej int
    327  1.19      dsl dwlpx_bus_dmamap_load_raw_sgmap(bus_dma_tag_t t, bus_dmamap_t map, bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags)
    328   1.2  thorpej {
    329   1.2  thorpej 
    330   1.2  thorpej 	return (pci_sgmap_pte32_load_raw(t, map, segs, nsegs, size, flags,
    331   1.9  thorpej 	    t->_sgmap));
    332   1.2  thorpej }
    333   1.2  thorpej 
    334   1.2  thorpej /*
    335   1.2  thorpej  * Unload a DWLPx DMA map.
    336   1.2  thorpej  */
    337   1.2  thorpej void
    338  1.19      dsl dwlpx_bus_dmamap_unload_sgmap(bus_dma_tag_t t, bus_dmamap_t map)
    339   1.2  thorpej {
    340   1.2  thorpej 
    341   1.2  thorpej 	/*
    342   1.2  thorpej 	 * Invalidate any SGMAP page table entries used by this
    343   1.2  thorpej 	 * mapping.
    344   1.2  thorpej 	 */
    345   1.9  thorpej 	pci_sgmap_pte32_unload(t, map, t->_sgmap);
    346   1.2  thorpej 
    347   1.2  thorpej 	/*
    348   1.2  thorpej 	 * Do the generic bits of the unload.
    349   1.2  thorpej 	 */
    350   1.2  thorpej 	_bus_dmamap_unload(t, map);
    351   1.2  thorpej }
    352