xref: /netbsd-src/sys/arch/alpha/pci/cia_dma.c (revision 9ac63422b666fbe53a067de74d8af2aa4e45a08b)
1 /* $NetBSD: cia_dma.c,v 1.28 2012/02/06 02:14:14 matt 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: cia_dma.c,v 1.28 2012/02/06 02:14:14 matt Exp $");
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/device.h>
41 #include <sys/malloc.h>
42 
43 #define _ALPHA_BUS_DMA_PRIVATE
44 #include <sys/bus.h>
45 
46 #include <dev/pci/pcireg.h>
47 #include <dev/pci/pcivar.h>
48 #include <alpha/pci/ciareg.h>
49 #include <alpha/pci/ciavar.h>
50 
51 bus_dma_tag_t cia_dma_get_tag(bus_dma_tag_t, alpha_bus_t);
52 
53 int	cia_bus_dmamap_create_direct(bus_dma_tag_t, bus_size_t, int,
54 	    bus_size_t, bus_size_t, int, bus_dmamap_t *);
55 
56 int	cia_bus_dmamap_load_sgmap(bus_dma_tag_t, bus_dmamap_t, void *,
57 	    bus_size_t, struct proc *, int);
58 
59 int	cia_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t, bus_dmamap_t,
60 	    struct mbuf *, int);
61 
62 int	cia_bus_dmamap_load_uio_sgmap(bus_dma_tag_t, bus_dmamap_t,
63 	    struct uio *, int);
64 
65 int	cia_bus_dmamap_load_raw_sgmap(bus_dma_tag_t, bus_dmamap_t,
66 	    bus_dma_segment_t *, int, bus_size_t, int);
67 
68 void	cia_bus_dmamap_unload_sgmap(bus_dma_tag_t, bus_dmamap_t);
69 
70 /*
71  * Direct-mapped window: 1G at 1G
72  */
73 #define	CIA_DIRECT_MAPPED_BASE	(1*1024*1024*1024)
74 #define	CIA_DIRECT_MAPPED_SIZE	(1*1024*1024*1024)
75 
76 /*
77  * SGMAP window: 8M at 8M
78  */
79 #define	CIA_SGMAP_MAPPED_BASE	(8*1024*1024)
80 #define	CIA_SGMAP_MAPPED_SIZE	(8*1024*1024)
81 
82 /* ALCOR/ALGOR2/PYXIS have a 256-byte out-bound DMA prefetch threshold. */
83 #define	CIA_SGMAP_PFTHRESH	256
84 
85 void	cia_tlb_invalidate(void);
86 void	cia_broken_pyxis_tlb_invalidate(void);
87 
88 void	(*cia_tlb_invalidate_fn)(void);
89 
90 #define	CIA_TLB_INVALIDATE()	(*cia_tlb_invalidate_fn)()
91 
92 struct alpha_sgmap cia_pyxis_bug_sgmap;
93 #define	CIA_PYXIS_BUG_BASE	(128*1024*1024)
94 #define	CIA_PYXIS_BUG_SIZE	(2*1024*1024)
95 
96 void
97 cia_dma_init(struct cia_config *ccp)
98 {
99 	bus_addr_t tbase;
100 	bus_dma_tag_t t;
101 
102 	/*
103 	 * Initialize the DMA tag used for direct-mapped DMA.
104 	 */
105 	t = &ccp->cc_dmat_direct;
106 	t->_cookie = ccp;
107 	t->_wbase = CIA_DIRECT_MAPPED_BASE;
108 	t->_wsize = CIA_DIRECT_MAPPED_SIZE;
109 	t->_next_window = &ccp->cc_dmat_sgmap;
110 	t->_boundary = 0;
111 	t->_sgmap = NULL;
112 	t->_get_tag = cia_dma_get_tag;
113 	t->_dmamap_create = cia_bus_dmamap_create_direct;
114 	t->_dmamap_destroy = _bus_dmamap_destroy;
115 	t->_dmamap_load = _bus_dmamap_load_direct;
116 	t->_dmamap_load_mbuf = _bus_dmamap_load_mbuf_direct;
117 	t->_dmamap_load_uio = _bus_dmamap_load_uio_direct;
118 	t->_dmamap_load_raw = _bus_dmamap_load_raw_direct;
119 	t->_dmamap_unload = _bus_dmamap_unload;
120 	t->_dmamap_sync = _bus_dmamap_sync;
121 
122 	t->_dmamem_alloc = _bus_dmamem_alloc;
123 	t->_dmamem_free = _bus_dmamem_free;
124 	t->_dmamem_map = _bus_dmamem_map;
125 	t->_dmamem_unmap = _bus_dmamem_unmap;
126 	t->_dmamem_mmap = _bus_dmamem_mmap;
127 
128 	/*
129 	 * Initialize the DMA tag used for sgmap-mapped DMA.
130 	 */
131 	t = &ccp->cc_dmat_sgmap;
132 	t->_cookie = ccp;
133 	t->_wbase = CIA_SGMAP_MAPPED_BASE;
134 	t->_wsize = CIA_SGMAP_MAPPED_SIZE;
135 	t->_next_window = NULL;
136 	t->_boundary = 0;
137 	t->_sgmap = &ccp->cc_sgmap;
138 	t->_pfthresh = CIA_SGMAP_PFTHRESH;
139 	t->_get_tag = cia_dma_get_tag;
140 	t->_dmamap_create = alpha_sgmap_dmamap_create;
141 	t->_dmamap_destroy = alpha_sgmap_dmamap_destroy;
142 	t->_dmamap_load = cia_bus_dmamap_load_sgmap;
143 	t->_dmamap_load_mbuf = cia_bus_dmamap_load_mbuf_sgmap;
144 	t->_dmamap_load_uio = cia_bus_dmamap_load_uio_sgmap;
145 	t->_dmamap_load_raw = cia_bus_dmamap_load_raw_sgmap;
146 	t->_dmamap_unload = cia_bus_dmamap_unload_sgmap;
147 	t->_dmamap_sync = _bus_dmamap_sync;
148 
149 	t->_dmamem_alloc = _bus_dmamem_alloc;
150 	t->_dmamem_free = _bus_dmamem_free;
151 	t->_dmamem_map = _bus_dmamem_map;
152 	t->_dmamem_unmap = _bus_dmamem_unmap;
153 	t->_dmamem_mmap = _bus_dmamem_mmap;
154 
155 	/*
156 	 * The firmware has set up window 1 as a 1G direct-mapped DMA
157 	 * window beginning at 1G.  We leave it alone.  Leave window
158 	 * 0 alone until we reconfigure it for SGMAP-mapped DMA.
159 	 * Windows 2 and 3 are already disabled.
160 	 */
161 
162 	/*
163 	 * Initialize the SGMAP.  Must align page table to 32k
164 	 * (hardware bug?).
165 	 */
166 	alpha_sgmap_init(t, &ccp->cc_sgmap, "cia_sgmap",
167 	    CIA_SGMAP_MAPPED_BASE, 0, CIA_SGMAP_MAPPED_SIZE,
168 	    sizeof(uint64_t), NULL, (32*1024));
169 
170 	/*
171 	 * Set up window 0 as an 8MB SGMAP-mapped window
172 	 * starting at 8MB.
173 	 */
174 	REGVAL(CIA_PCI_W0BASE) = CIA_SGMAP_MAPPED_BASE |
175 	    CIA_PCI_WnBASE_SG_EN | CIA_PCI_WnBASE_W_EN;
176 	alpha_mb();
177 
178 	REGVAL(CIA_PCI_W0MASK) = CIA_PCI_WnMASK_8M;
179 	alpha_mb();
180 
181 	tbase = ccp->cc_sgmap.aps_ptpa >> CIA_PCI_TnBASE_SHIFT;
182 	if ((tbase & CIA_PCI_TnBASE_MASK) != tbase)
183 		panic("cia_dma_init: bad page table address");
184 	REGVAL(CIA_PCI_T0BASE) = tbase;
185 	alpha_mb();
186 
187 	/*
188 	 * Pass 1 and 2 (i.e. revision <= 1) of the Pyxis have a
189 	 * broken scatter/gather TLB; it cannot be invalidated.  To
190 	 * work around this problem, we configure window 2 as an SG
191 	 * 2M window at 128M, which we use in DMA loopback mode to
192 	 * read a spill page.  This works by causing TLB misses,
193 	 * causing the old entries to be purged to make room for
194 	 * the new entries coming in for the spill page.
195 	 */
196 	if ((ccp->cc_flags & CCF_ISPYXIS) != 0 && ccp->cc_rev <= 1) {
197 		uint64_t *page_table;
198 		int i;
199 
200 		cia_tlb_invalidate_fn =
201 		    cia_broken_pyxis_tlb_invalidate;
202 
203 		alpha_sgmap_init(t, &cia_pyxis_bug_sgmap,
204 		    "pyxis_bug_sgmap", CIA_PYXIS_BUG_BASE, 0,
205 		    CIA_PYXIS_BUG_SIZE, sizeof(uint64_t), NULL,
206 		    (32*1024));
207 
208 		REGVAL(CIA_PCI_W2BASE) = CIA_PYXIS_BUG_BASE |
209 		    CIA_PCI_WnBASE_SG_EN | CIA_PCI_WnBASE_W_EN;
210 		alpha_mb();
211 
212 		REGVAL(CIA_PCI_W2MASK) = CIA_PCI_WnMASK_2M;
213 		alpha_mb();
214 
215 		tbase = cia_pyxis_bug_sgmap.aps_ptpa >>
216 		    CIA_PCI_TnBASE_SHIFT;
217 		if ((tbase & CIA_PCI_TnBASE_MASK) != tbase)
218 			panic("cia_dma_init: bad page table address");
219 		REGVAL(CIA_PCI_T2BASE) = tbase;
220 		alpha_mb();
221 
222 		/*
223 		 * Initialize the page table to point at the spill
224 		 * page.  Leave the last entry invalid.
225 		 */
226 		pci_sgmap_pte64_init_spill_page_pte();
227 		for (i = 0, page_table = cia_pyxis_bug_sgmap.aps_pt;
228 		     i < (CIA_PYXIS_BUG_SIZE / PAGE_SIZE) - 1; i++) {
229 			page_table[i] =
230 			    pci_sgmap_pte64_prefetch_spill_page_pte;
231 		}
232 		alpha_mb();
233 	} else
234 		cia_tlb_invalidate_fn = cia_tlb_invalidate;
235 
236 	CIA_TLB_INVALIDATE();
237 
238 	/* XXX XXX BEGIN XXX XXX */
239 	{							/* XXX */
240 		extern paddr_t alpha_XXX_dmamap_or;		/* XXX */
241 		alpha_XXX_dmamap_or = CIA_DIRECT_MAPPED_BASE;	/* XXX */
242 	}							/* XXX */
243 	/* XXX XXX END XXX XXX */
244 }
245 
246 /*
247  * Return the bus dma tag to be used for the specified bus type.
248  * INTERNAL USE ONLY!
249  */
250 bus_dma_tag_t
251 cia_dma_get_tag(bus_dma_tag_t t, alpha_bus_t bustype)
252 {
253 	struct cia_config *ccp = t->_cookie;
254 
255 	switch (bustype) {
256 	case ALPHA_BUS_PCI:
257 	case ALPHA_BUS_EISA:
258 		/*
259 		 * Systems with a CIA can only support 1G
260 		 * of memory, so we use the direct-mapped window
261 		 * on busses that have 32-bit DMA.
262 		 *
263 		 * Ahem:  I have a PWS 500au with 1.5G of memory, and it
264 		 * had problems doing DMA because it was not falling back
265 		 * to using SGMAPs.  I've fixed that and my PWS now works with
266 		 * 1.5G.  There have been other reports about failures with
267 		 * more than 1.0G of memory.  Michael Hitch
268 		 */
269 		return (&ccp->cc_dmat_direct);
270 
271 	case ALPHA_BUS_ISA:
272 		/*
273 		 * ISA doesn't have enough address bits to use
274 		 * the direct-mapped DMA window, so we must use
275 		 * SGMAPs.
276 		 */
277 		return (&ccp->cc_dmat_sgmap);
278 
279 	default:
280 		panic("cia_dma_get_tag: shouldn't be here, really...");
281 	}
282 }
283 
284 /*
285  * Create a CIA direct-mapped DMA map.
286  */
287 int
288 cia_bus_dmamap_create_direct(
289 	bus_dma_tag_t t,
290 	bus_size_t size,
291 	int nsegments,
292 	bus_size_t maxsegsz,
293 	bus_size_t boundary,
294 	int flags,
295 	bus_dmamap_t *dmamp)
296 {
297 	struct cia_config *ccp = t->_cookie;
298 	bus_dmamap_t map;
299 	int error;
300 
301 	error = _bus_dmamap_create(t, size, nsegments, maxsegsz,
302 	    boundary, flags, dmamp);
303 	if (error)
304 		return (error);
305 
306 	map = *dmamp;
307 
308 	if ((ccp->cc_flags & CCF_PYXISBUG) != 0 &&
309 	    map->_dm_segcnt > 1) {
310 		/*
311 		 * We have a Pyxis with the DMA page crossing bug, make
312 		 * sure we don't coalesce adjacent DMA segments.
313 		 *
314 		 * NOTE: We can only do this if the max segment count
315 		 * is greater than 1.  This is because many network
316 		 * drivers allocate large contiguous blocks of memory
317 		 * for control data structures, even though they won't
318 		 * do any single DMA that crosses a page coundary.
319 		 *	-- thorpej@NetBSD.org, 2/5/2000
320 		 */
321 		map->_dm_flags |= DMAMAP_NO_COALESCE;
322 	}
323 
324 	return (0);
325 }
326 
327 /*
328  * Load a CIA SGMAP-mapped DMA map with a linear buffer.
329  */
330 int
331 cia_bus_dmamap_load_sgmap(bus_dma_tag_t t, bus_dmamap_t map, void *buf, bus_size_t buflen, struct proc *p, int flags)
332 {
333 	int error;
334 
335 	error = pci_sgmap_pte64_load(t, map, buf, buflen, p, flags,
336 	    t->_sgmap);
337 	if (error == 0)
338 		CIA_TLB_INVALIDATE();
339 
340 	return (error);
341 }
342 
343 /*
344  * Load a CIA SGMAP-mapped DMA map with an mbuf chain.
345  */
346 int
347 cia_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m, int flags)
348 {
349 	int error;
350 
351 	error = pci_sgmap_pte64_load_mbuf(t, map, m, flags, t->_sgmap);
352 	if (error == 0)
353 		CIA_TLB_INVALIDATE();
354 
355 	return (error);
356 }
357 
358 /*
359  * Load a CIA SGMAP-mapped DMA map with a uio.
360  */
361 int
362 cia_bus_dmamap_load_uio_sgmap(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio, int flags)
363 {
364 	int error;
365 
366 	error = pci_sgmap_pte64_load_uio(t, map, uio, flags, t->_sgmap);
367 	if (error == 0)
368 		CIA_TLB_INVALIDATE();
369 
370 	return (error);
371 }
372 
373 /*
374  * Load a CIA SGMAP-mapped DMA map with raw memory.
375  */
376 int
377 cia_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)
378 {
379 	int error;
380 
381 	error = pci_sgmap_pte64_load_raw(t, map, segs, nsegs, size, flags,
382 	    t->_sgmap);
383 	if (error == 0)
384 		CIA_TLB_INVALIDATE();
385 
386 	return (error);
387 }
388 
389 /*
390  * Unload a CIA DMA map.
391  */
392 void
393 cia_bus_dmamap_unload_sgmap(bus_dma_tag_t t, bus_dmamap_t map)
394 {
395 
396 	/*
397 	 * Invalidate any SGMAP page table entries used by this
398 	 * mapping.
399 	 */
400 	pci_sgmap_pte64_unload(t, map, t->_sgmap);
401 	CIA_TLB_INVALIDATE();
402 
403 	/*
404 	 * Do the generic bits of the unload.
405 	 */
406 	_bus_dmamap_unload(t, map);
407 }
408 
409 /*
410  * Flush the CIA scatter/gather TLB.
411  */
412 void
413 cia_tlb_invalidate(void)
414 {
415 
416 	alpha_mb();
417 	REGVAL(CIA_PCI_TBIA) = CIA_PCI_TBIA_ALL;
418 	alpha_mb();
419 }
420 
421 /*
422  * Flush the scatter/gather TLB on broken Pyxis chips.
423  */
424 void
425 cia_broken_pyxis_tlb_invalidate(void)
426 {
427 	volatile uint64_t dummy;
428 	uint32_t ctrl;
429 	int i, s;
430 
431 	s = splhigh();
432 
433 	/*
434 	 * Put the Pyxis into PCI loopback mode.
435 	 */
436 	alpha_mb();
437 	ctrl = REGVAL(CIA_CSR_CTRL);
438 	REGVAL(CIA_CSR_CTRL) = ctrl | CTRL_PCI_LOOP_EN;
439 	alpha_mb();
440 
441 	/*
442 	 * Now, read from PCI dense memory space at offset 128M (our
443 	 * target window base), skipping 64k on each read.  This forces
444 	 * S/G TLB misses.
445 	 *
446 	 * XXX Looks like the TLB entries are `not quite LRU'.  We need
447 	 * XXX to read more times than there are actual tags!
448 	 */
449 	for (i = 0; i < CIA_TLB_NTAGS + 4; i++) {
450 		dummy = *((volatile uint64_t *)
451 		    ALPHA_PHYS_TO_K0SEG(CIA_PCI_DENSE + CIA_PYXIS_BUG_BASE +
452 		    (i * 65536)));
453 	}
454 
455 	/*
456 	 * Restore normal PCI operation.
457 	 */
458 	alpha_mb();
459 	REGVAL(CIA_CSR_CTRL) = ctrl;
460 	alpha_mb();
461 
462 	splx(s);
463 }
464