1/* $OpenBSD: sgmap_common.c,v 1.15 2019/05/13 21:27:59 mpi Exp $ */
2/* $NetBSD: sgmap_common.c,v 1.13 2000/06/29 09:02:57 mrg Exp $ */
3
4/*-
5 * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to The NetBSD Foundation
9 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
10 * NASA Ames Research Center.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#define _ALPHA_BUS_DMA_PRIVATE
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/kernel.h>
39#include <sys/malloc.h>
40#include <sys/proc.h>
41
42#include <uvm/uvm_extern.h>
43
44#include <machine/bus.h>
45
46#include <alpha/dev/sgmapvar.h>
47
48/*
49 * Some systems will prefetch the next page during a memory -> device DMA.
50 * This can cause machine checks if there is not a spill page after the
51 * last page of the DMA (thus avoiding hitting an invalid SGMAP PTE).
52 */
53vaddr_t		alpha_sgmap_prefetch_spill_page_va;
54bus_addr_t	alpha_sgmap_prefetch_spill_page_pa;
55
56void
57alpha_sgmap_init(t, sgmap, name, wbase, sgvabase, sgvasize, ptesize, ptva,
58    minptalign)
59	bus_dma_tag_t t;
60	struct alpha_sgmap *sgmap;
61	const char *name;
62	bus_addr_t wbase;
63	bus_addr_t sgvabase;
64	bus_size_t sgvasize;
65	size_t ptesize;
66	void *ptva;
67	bus_size_t minptalign;
68{
69	bus_dma_segment_t seg;
70	size_t ptsize;
71	int rseg;
72
73	if (sgvasize & PGOFSET) {
74		printf("size botch for sgmap `%s'\n", name);
75		goto die;
76	}
77
78	sgmap->aps_wbase = wbase;
79	sgmap->aps_sgvabase = sgvabase;
80	sgmap->aps_sgvasize = sgvasize;
81
82	if (ptva != NULL) {
83		/*
84		 * We already have a page table; this may be a system
85		 * where the page table resides in bridge-resident SRAM.
86		 */
87		sgmap->aps_pt = ptva;
88		sgmap->aps_ptpa = 0;
89	} else {
90		/*
91		 * Compute the page table size and allocate it.  At minimum,
92		 * this must be aligned to the page table size.  However,
93		 * some platforms have more strict alignment requirements.
94		 */
95		ptsize = (sgvasize / PAGE_SIZE) * ptesize;
96		if (minptalign != 0) {
97			if (minptalign < ptsize)
98				minptalign = ptsize;
99		} else
100			minptalign = ptsize;
101		if (bus_dmamem_alloc(t, ptsize, minptalign, 0, &seg, 1, &rseg,
102		    BUS_DMA_NOWAIT)) {
103			panic("unable to allocate page table for sgmap `%s'",
104			    name);
105			goto die;
106		}
107		sgmap->aps_ptpa = seg.ds_addr;
108		sgmap->aps_pt = (caddr_t)ALPHA_PHYS_TO_K0SEG(sgmap->aps_ptpa);
109	}
110
111	/*
112	 * Create the extent map used to manage the virtual address
113	 * space.
114	 */
115	sgmap->aps_ex = extent_create((char *)name, sgvabase, sgvasize - 1,
116	    M_DEVBUF, NULL, 0, EX_NOWAIT|EX_NOCOALESCE);
117	if (sgmap->aps_ex == NULL) {
118		printf("unable to create extent map for sgmap `%s'\n",
119		    name);
120		goto die;
121	}
122	mtx_init(&sgmap->aps_mtx, IPL_HIGH);
123
124	/*
125	 * Allocate a spill page if that hasn't already been done.
126	 */
127	if (alpha_sgmap_prefetch_spill_page_va == 0) {
128		if (bus_dmamem_alloc(t, PAGE_SIZE, 0, 0, &seg, 1, &rseg,
129		    BUS_DMA_NOWAIT)) {
130			printf("unable to allocate spill page for sgmap `%s'\n",
131			    name);
132			goto die;
133		}
134		alpha_sgmap_prefetch_spill_page_pa = seg.ds_addr;
135		alpha_sgmap_prefetch_spill_page_va =
136		    ALPHA_PHYS_TO_K0SEG(alpha_sgmap_prefetch_spill_page_pa);
137		bzero((caddr_t)alpha_sgmap_prefetch_spill_page_va, PAGE_SIZE);
138	}
139
140	return;
141 die:
142	panic("alpha_sgmap_init");
143}
144
145int
146alpha_sgmap_dmamap_setup(map, nsegments, flags)
147	bus_dmamap_t map;
148	int nsegments;
149	int flags;
150{
151	map->_dm_cookie = mallocarray(nsegments, sizeof(struct extent_region),
152	    M_DEVBUF, (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
153	if (map->_dm_cookie != NULL)
154		map->_dm_cookiesize = nsegments * sizeof(struct extent_region);
155	return (map->_dm_cookie == NULL);
156}
157
158int
159alpha_sgmap_dmamap_create(t, size, nsegments, maxsegsz, boundary,
160    flags, dmamp)
161	bus_dma_tag_t t;
162	bus_size_t size;
163	int nsegments;
164	bus_size_t maxsegsz;
165	bus_size_t boundary;
166	int flags;
167	bus_dmamap_t *dmamp;
168{
169	bus_dmamap_t map;
170	int error;
171
172	error = _bus_dmamap_create(t, size, nsegments, maxsegsz,
173	    boundary, flags, dmamp);
174	if (error)
175		return (error);
176
177	map = *dmamp;
178	if (alpha_sgmap_dmamap_setup(map, nsegments, flags)) {
179		_bus_dmamap_destroy(t, map);
180		return (ENOMEM);
181	}
182
183	/* XXX BUS_DMA_ALLOCNOW */
184
185	return (0);
186}
187
188void
189alpha_sgmap_dmamap_teardown(map)
190	bus_dmamap_t map;
191{
192	free(map->_dm_cookie, M_DEVBUF, map->_dm_cookiesize);
193}
194
195void
196alpha_sgmap_dmamap_destroy(t, map)
197	bus_dma_tag_t t;
198	bus_dmamap_t map;
199{
200	KASSERT(map->dm_mapsize == 0);
201
202	alpha_sgmap_dmamap_teardown(map);
203	_bus_dmamap_destroy(t, map);
204}
205