1/* $NetBSD: apecs_dma.c,v 1.25 2021/07/04 22:42:36 thorpej Exp $ */
2
3/*-
4 * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
34
35__KERNEL_RCSID(0, "$NetBSD: apecs_dma.c,v 1.25 2021/07/04 22:42:36 thorpej Exp $");
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/kernel.h>
40#include <sys/device.h>
41
42#define _ALPHA_BUS_DMA_PRIVATE
43#include <sys/bus.h>
44
45#include <dev/pci/pcireg.h>
46#include <dev/pci/pcivar.h>
47#include <alpha/pci/apecsreg.h>
48#include <alpha/pci/apecsvar.h>
49
50static bus_dma_tag_t apecs_dma_get_tag(bus_dma_tag_t, alpha_bus_t);
51
52static int	apecs_bus_dmamap_load_sgmap(bus_dma_tag_t, bus_dmamap_t, void *,
53		    bus_size_t, struct proc *, int);
54
55static int	apecs_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t, bus_dmamap_t,
56		    struct mbuf *, int);
57
58static int	apecs_bus_dmamap_load_uio_sgmap(bus_dma_tag_t, bus_dmamap_t,
59		    struct uio *, int);
60
61static int	apecs_bus_dmamap_load_raw_sgmap(bus_dma_tag_t, bus_dmamap_t,
62		    bus_dma_segment_t *, int, bus_size_t, int);
63
64static void	apecs_bus_dmamap_unload_sgmap(bus_dma_tag_t, bus_dmamap_t);
65
66/*
67 * Direct-mapped window: 1G at 1G
68 */
69#define	APECS_DIRECT_MAPPED_BASE (1*1024*1024*1024)
70#define	APECS_DIRECT_MAPPED_SIZE (1*1024*1024*1024)
71
72/*
73 * SGMAP window: 8M at 8M
74 */
75#define	APECS_SGMAP_MAPPED_BASE	(8*1024*1024)
76#define	APECS_SGMAP_MAPPED_SIZE	(8*1024*1024)
77
78/* APECS has a 256-byte out-bound DMA prefetch threshold. */
79#define	APECS_SGMAP_PFTHRESH	256
80
81/*
82 * Macro to flush APECS scatter/gather TLB.
83 */
84#define	APECS_TLB_INVALIDATE() \
85do { \
86	alpha_mb(); \
87	REGVAL(EPIC_TBIA) = 0; \
88	alpha_mb(); \
89} while (0)
90
91void
92apecs_dma_init(struct apecs_config *acp)
93{
94	bus_addr_t tbase;
95	bus_dma_tag_t t;
96
97	/*
98	 * Initialize the DMA tag used for direct-mapped DMA.
99	 */
100	t = &acp->ac_dmat_direct;
101	t->_cookie = acp;
102	t->_wbase = APECS_DIRECT_MAPPED_BASE;
103	t->_wsize = APECS_DIRECT_MAPPED_SIZE;
104	t->_next_window = NULL;
105	t->_boundary = 0;
106	t->_sgmap = NULL;
107	t->_get_tag = apecs_dma_get_tag;
108	t->_dmamap_create = _bus_dmamap_create;
109	t->_dmamap_destroy = _bus_dmamap_destroy;
110	t->_dmamap_load = _bus_dmamap_load_direct;
111	t->_dmamap_load_mbuf = _bus_dmamap_load_mbuf_direct;
112	t->_dmamap_load_uio = _bus_dmamap_load_uio_direct;
113	t->_dmamap_load_raw = _bus_dmamap_load_raw_direct;
114	t->_dmamap_unload = _bus_dmamap_unload;
115	t->_dmamap_sync = _bus_dmamap_sync;
116
117	t->_dmamem_alloc = _bus_dmamem_alloc;
118	t->_dmamem_free = _bus_dmamem_free;
119	t->_dmamem_map = _bus_dmamem_map;
120	t->_dmamem_unmap = _bus_dmamem_unmap;
121	t->_dmamem_mmap = _bus_dmamem_mmap;
122
123	/*
124	 * Initialize the DMA tag used for sgmap-mapped DMA.
125	 */
126	t = &acp->ac_dmat_sgmap;
127	t->_cookie = acp;
128	t->_wbase = APECS_SGMAP_MAPPED_BASE;
129	t->_wsize = APECS_SGMAP_MAPPED_SIZE;
130	t->_next_window = NULL;
131	t->_boundary = 0;
132	t->_sgmap = &acp->ac_sgmap;
133	t->_pfthresh = APECS_SGMAP_PFTHRESH;
134	t->_get_tag = apecs_dma_get_tag;
135	t->_dmamap_create = alpha_sgmap_dmamap_create;
136	t->_dmamap_destroy = alpha_sgmap_dmamap_destroy;
137	t->_dmamap_load = apecs_bus_dmamap_load_sgmap;
138	t->_dmamap_load_mbuf = apecs_bus_dmamap_load_mbuf_sgmap;
139	t->_dmamap_load_uio = apecs_bus_dmamap_load_uio_sgmap;
140	t->_dmamap_load_raw = apecs_bus_dmamap_load_raw_sgmap;
141	t->_dmamap_unload = apecs_bus_dmamap_unload_sgmap;
142	t->_dmamap_sync = _bus_dmamap_sync;
143
144	t->_dmamem_alloc = _bus_dmamem_alloc;
145	t->_dmamem_free = _bus_dmamem_free;
146	t->_dmamem_map = _bus_dmamem_map;
147	t->_dmamem_unmap = _bus_dmamem_unmap;
148	t->_dmamem_mmap = _bus_dmamem_mmap;
149
150	/*
151	 * The firmware has set up window 2 as a 1G direct-mapped DMA
152	 * window beginning at 1G.  We leave it alone.  Disable
153	 * window 1.
154	 */
155	REGVAL(EPIC_PCI_BASE_1) = 0;
156	alpha_mb();
157
158	/*
159	 * Initialize the SGMAP.
160	 */
161	alpha_sgmap_init(t, &acp->ac_sgmap, "apecs_sgmap",
162	    APECS_SGMAP_MAPPED_BASE, 0, APECS_SGMAP_MAPPED_SIZE,
163	    sizeof(uint64_t), NULL, 0);
164
165	/*
166	 * Set up window 1 as an 8MB SGMAP-mapped window
167	 * starting at 8MB.
168	 */
169	REGVAL(EPIC_PCI_BASE_1) = APECS_SGMAP_MAPPED_BASE |
170	    EPIC_PCI_BASE_SGEN | EPIC_PCI_BASE_WENB;
171	alpha_mb();
172
173	REGVAL(EPIC_PCI_MASK_1) = EPIC_PCI_MASK_8M;
174	alpha_mb();
175
176	tbase = acp->ac_sgmap.aps_ptpa >> EPIC_TBASE_SHIFT;
177	if ((tbase & EPIC_TBASE_T_BASE) != tbase)
178		panic("apecs_dma_init: bad page table address");
179	REGVAL(EPIC_TBASE_1) = tbase;
180	alpha_mb();
181
182	APECS_TLB_INVALIDATE();
183}
184
185/*
186 * Return the bus dma tag to be used for the specified bus type.
187 * INTERNAL USE ONLY!
188 */
189static bus_dma_tag_t
190apecs_dma_get_tag(bus_dma_tag_t t, alpha_bus_t bustype)
191{
192	struct apecs_config *acp = t->_cookie;
193
194	switch (bustype) {
195	case ALPHA_BUS_PCI:
196	case ALPHA_BUS_EISA:
197		/*
198		 * Systems with an APECS can only support 1G
199		 * of memory, so we use the direct-mapped window
200		 * on busses that have 32-bit DMA.
201		 */
202		return (&acp->ac_dmat_direct);
203
204	case ALPHA_BUS_ISA:
205		/*
206		 * ISA doesn't have enough address bits to use
207		 * the direct-mapped DMA window, so we must use
208		 * SGMAPs.
209		 */
210		return (&acp->ac_dmat_sgmap);
211
212	default:
213		panic("apecs_dma_get_tag: shouldn't be here, really...");
214	}
215}
216
217/*
218 * Load an APECS SGMAP-mapped DMA map with a linear buffer.
219 */
220static int
221apecs_bus_dmamap_load_sgmap(bus_dma_tag_t t, bus_dmamap_t map, void *buf, bus_size_t buflen, struct proc *p, int flags)
222{
223	int error;
224
225	error = pci_sgmap_pte64_load(t, map, buf, buflen, p, flags,
226	    t->_sgmap);
227	if (error == 0)
228		APECS_TLB_INVALIDATE();
229
230	return (error);
231}
232
233/*
234 * Load an APECS SGMAP-mapped DMA map with an mbuf chain.
235 */
236static int
237apecs_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m, int flags)
238{
239	int error;
240
241	error = pci_sgmap_pte64_load_mbuf(t, map, m, flags, t->_sgmap);
242	if (error == 0)
243		APECS_TLB_INVALIDATE();
244
245	return (error);
246}
247
248/*
249 * Load an APECS SGMAP-mapped DMA map with a uio.
250 */
251static int
252apecs_bus_dmamap_load_uio_sgmap(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio, int flags)
253{
254	int error;
255
256	error = pci_sgmap_pte64_load_uio(t, map, uio, flags, t->_sgmap);
257	if (error == 0)
258		APECS_TLB_INVALIDATE();
259
260	return (error);
261}
262
263/*
264 * Load an APECS SGMAP-mapped DMA map with raw memory.
265 */
266static int
267apecs_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)
268{
269	int error;
270
271	error = pci_sgmap_pte64_load_raw(t, map, segs, nsegs, size, flags,
272	    t->_sgmap);
273	if (error == 0)
274		APECS_TLB_INVALIDATE();
275
276	return (error);
277}
278
279/*
280 * Unload an APECS DMA map.
281 */
282static void
283apecs_bus_dmamap_unload_sgmap(bus_dma_tag_t t, bus_dmamap_t map)
284{
285
286	/*
287	 * Invalidate any SGMAP page table entries used by this
288	 * mapping.
289	 */
290	pci_sgmap_pte64_unload(t, map, t->_sgmap);
291	APECS_TLB_INVALIDATE();
292
293	/*
294	 * Do the generic bits of the unload.
295	 */
296	_bus_dmamap_unload_common(t, map);
297}
298