2 * Copyright (c) 2013 Daisuke Aoyama <aoyama@peach.ne.jp>
3 * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@bluezbox.com>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
32 #include <sys/systm.h>
34 #include <sys/kernel.h>
36 #include <sys/malloc.h>
37 #include <sys/module.h>
38 #include <sys/mutex.h>
39 #include <sys/queue.h>
40 #include <sys/resource.h>
43 #include <dev/fdt/fdt_common.h>
44 #include <dev/ofw/openfirm.h>
45 #include <dev/ofw/ofw_bus.h>
46 #include <dev/ofw/ofw_bus_subr.h>
50 #include <machine/bus.h>
51 #include <machine/cpu.h>
52 #include <machine/cpufunc.h>
54 #include "bcm2835_dma.h"
55 #include "bcm2835_vcbus.h"
60 #define BCM_DMA_CH_USED 0x00000001
61 #define BCM_DMA_CH_FREE 0x40000000
62 #define BCM_DMA_CH_UNMAP 0x80000000
64 /* Register Map (4.2.1.2) */
65 #define BCM_DMA_CS(n) (0x100*(n) + 0x00)
66 #define CS_ACTIVE (1 << 0)
67 #define CS_END (1 << 1)
68 #define CS_INT (1 << 2)
69 #define CS_DREQ (1 << 3)
70 #define CS_ISPAUSED (1 << 4)
71 #define CS_ISHELD (1 << 5)
72 #define CS_ISWAIT (1 << 6)
73 #define CS_ERR (1 << 8)
74 #define CS_WAITWRT (1 << 28)
75 #define CS_DISDBG (1 << 29)
76 #define CS_ABORT (1 << 30)
77 #define CS_RESET (1U << 31)
78 #define BCM_DMA_CBADDR(n) (0x100*(n) + 0x04)
79 #define BCM_DMA_INFO(n) (0x100*(n) + 0x08)
80 #define INFO_INT_EN (1 << 0)
81 #define INFO_TDMODE (1 << 1)
82 #define INFO_WAIT_RESP (1 << 3)
83 #define INFO_D_INC (1 << 4)
84 #define INFO_D_WIDTH (1 << 5)
85 #define INFO_D_DREQ (1 << 6)
86 #define INFO_S_INC (1 << 8)
87 #define INFO_S_WIDTH (1 << 9)
88 #define INFO_S_DREQ (1 << 10)
89 #define INFO_WAITS_SHIFT (21)
90 #define INFO_PERMAP_SHIFT (16)
91 #define INFO_PERMAP_MASK (0x1f << INFO_PERMAP_SHIFT)
93 #define BCM_DMA_SRC(n) (0x100*(n) + 0x0C)
94 #define BCM_DMA_DST(n) (0x100*(n) + 0x10)
95 #define BCM_DMA_LEN(n) (0x100*(n) + 0x14)
96 #define BCM_DMA_STRIDE(n) (0x100*(n) + 0x18)
97 #define BCM_DMA_CBNEXT(n) (0x100*(n) + 0x1C)
98 #define BCM_DMA_DEBUG(n) (0x100*(n) + 0x20)
99 #define DEBUG_ERROR_MASK (7)
101 #define BCM_DMA_INT_STATUS 0xfe0
102 #define BCM_DMA_ENABLE 0xff0
104 /* relative offset from BCM_VC_DMA0_BASE (p.39) */
105 #define BCM_DMA_CH(n) (0x100*(n))
107 /* DMA Control Block - 256bit aligned (p.40) */
109 uint32_t info; /* Transfer Information */
110 uint32_t src; /* Source Address */
111 uint32_t dst; /* Destination Address */
112 uint32_t len; /* Transfer Length */
113 uint32_t stride; /* 2D Mode Stride */
114 uint32_t next; /* Next Control Block Address */
115 uint32_t rsvd1; /* Reserved */
116 uint32_t rsvd2; /* Reserved */
120 static void bcm_dma_cb_dump(struct bcm_dma_cb *cb);
121 static void bcm_dma_reg_dump(int ch);
124 /* DMA channel private info */
128 struct bcm_dma_cb * cb;
130 bus_dmamap_t dma_map;
131 void (*intr_func)(int, void *);
135 struct bcm_dma_softc {
138 struct resource * sc_mem;
139 struct resource * sc_irq[BCM_DMA_CH_MAX];
140 void * sc_intrhand[BCM_DMA_CH_MAX];
141 struct bcm_dma_ch sc_dma_ch[BCM_DMA_CH_MAX];
142 bus_dma_tag_t sc_dma_tag;
145 static struct bcm_dma_softc *bcm_dma_sc = NULL;
148 bcm_dmamap_cb(void *arg, bus_dma_segment_t *segs,
156 addr = (bus_addr_t*)arg;
157 *addr = PHYS_TO_VCBUS(segs[0].ds_addr);
161 bcm_dma_reset(device_t dev, int ch)
163 struct bcm_dma_softc *sc = device_get_softc(dev);
164 struct bcm_dma_cb *cb;
168 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
171 cs = bus_read_4(sc->sc_mem, BCM_DMA_CS(ch));
173 if (cs & CS_ACTIVE) {
174 /* pause current task */
175 bus_write_4(sc->sc_mem, BCM_DMA_CS(ch), 0);
179 cs = bus_read_4(sc->sc_mem, BCM_DMA_CS(ch));
180 } while (!(cs & CS_ISPAUSED) && (count-- > 0));
182 if (!(cs & CS_ISPAUSED)) {
184 "Can't abort DMA transfer at channel %d\n", ch);
187 bus_write_4(sc->sc_mem, BCM_DMA_CBNEXT(ch), 0);
189 /* Complete everything, clear interrupt */
190 bus_write_4(sc->sc_mem, BCM_DMA_CS(ch),
191 CS_ABORT | CS_INT | CS_END| CS_ACTIVE);
194 /* clear control blocks */
195 bus_write_4(sc->sc_mem, BCM_DMA_CBADDR(ch), 0);
196 bus_write_4(sc->sc_mem, BCM_DMA_CBNEXT(ch), 0);
198 /* Reset control block */
199 cb = sc->sc_dma_ch[ch].cb;
200 bzero(cb, sizeof(*cb));
201 cb->info = INFO_WAIT_RESP;
205 bcm_dma_init(device_t dev)
207 struct bcm_dma_softc *sc = device_get_softc(dev);
209 struct bcm_dma_ch *ch;
215 /* disable and clear interrupt status */
216 bus_write_4(sc->sc_mem, BCM_DMA_ENABLE, 0);
217 bus_write_4(sc->sc_mem, BCM_DMA_INT_STATUS, 0);
219 /* Allocate DMA chunks control blocks */
220 /* p.40 of spec - control block should be 32-bit aligned */
221 err = bus_dma_tag_create(bus_get_dma_tag(dev),
222 1, 0, BUS_SPACE_MAXADDR_32BIT,
223 BUS_SPACE_MAXADDR, NULL, NULL,
224 sizeof(struct bcm_dma_cb), 1,
225 sizeof(struct bcm_dma_cb),
226 BUS_DMA_ALLOCNOW, NULL, NULL,
230 device_printf(dev, "failed allocate DMA tag");
234 /* setup initial settings */
235 for (i = 0; i < BCM_DMA_CH_MAX; i++) {
236 ch = &sc->sc_dma_ch[i];
238 err = bus_dmamem_alloc(sc->sc_dma_tag, &cb_virt,
239 BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
242 device_printf(dev, "cannot allocate DMA memory\n");
247 * Least alignment for busdma-allocated stuff is cache
248 * line size, so just make sure nothing stupid happend
249 * and we got properly aligned address
251 if ((uintptr_t)cb_virt & 0x1f) {
253 "DMA address is not 32-bytes aligned: %p\n",
258 err = bus_dmamap_load(sc->sc_dma_tag, ch->dma_map, cb_virt,
259 sizeof(struct bcm_dma_cb), bcm_dmamap_cb, &cb_phys,
262 device_printf(dev, "cannot load DMA memory\n");
266 bzero(ch, sizeof(struct bcm_dma_ch));
270 ch->intr_func = NULL;
272 ch->flags = BCM_DMA_CH_UNMAP;
274 ch->cb->info = INFO_WAIT_RESP;
276 /* reset DMA engine */
277 bcm_dma_reset(dev, i);
280 /* now use DMA2/DMA3 only */
281 sc->sc_dma_ch[2].flags = BCM_DMA_CH_FREE;
282 sc->sc_dma_ch[3].flags = BCM_DMA_CH_FREE;
287 for (i = 0; i < BCM_DMA_CH_MAX; i++)
288 if (sc->sc_dma_ch[i].flags & BCM_DMA_CH_FREE)
291 bus_write_4(sc->sc_mem, BCM_DMA_ENABLE, mask);
297 * Allocate DMA channel for further use, returns channel # or
301 bcm_dma_allocate(int req_ch)
303 struct bcm_dma_softc *sc = bcm_dma_sc;
304 int ch = BCM_DMA_CH_INVALID;
307 if (req_ch >= BCM_DMA_CH_MAX)
308 return (BCM_DMA_CH_INVALID);
310 /* Auto(req_ch < 0) or CH specified */
311 mtx_lock(&sc->sc_mtx);
314 for (i = 0; i < BCM_DMA_CH_MAX; i++) {
315 if (sc->sc_dma_ch[i].flags & BCM_DMA_CH_FREE) {
317 sc->sc_dma_ch[ch].flags &= ~BCM_DMA_CH_FREE;
318 sc->sc_dma_ch[ch].flags |= BCM_DMA_CH_USED;
324 if (sc->sc_dma_ch[req_ch].flags & BCM_DMA_CH_FREE) {
326 sc->sc_dma_ch[ch].flags &= ~BCM_DMA_CH_FREE;
327 sc->sc_dma_ch[ch].flags |= BCM_DMA_CH_USED;
331 mtx_unlock(&sc->sc_mtx);
336 * Frees allocated channel. Returns 0 on success, -1 otherwise
341 struct bcm_dma_softc *sc = bcm_dma_sc;
343 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
346 mtx_lock(&sc->sc_mtx);
347 if (sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED) {
348 sc->sc_dma_ch[ch].flags |= BCM_DMA_CH_FREE;
349 sc->sc_dma_ch[ch].flags &= ~BCM_DMA_CH_USED;
350 sc->sc_dma_ch[ch].intr_func = NULL;
351 sc->sc_dma_ch[ch].intr_arg = NULL;
353 /* reset DMA engine */
354 bcm_dma_reset(sc->sc_dev, ch);
357 mtx_unlock(&sc->sc_mtx);
362 * Assign handler function for channel interrupt
363 * Returns 0 on success, -1 otherwise
366 bcm_dma_setup_intr(int ch, void (*func)(int, void *), void *arg)
368 struct bcm_dma_softc *sc = bcm_dma_sc;
369 struct bcm_dma_cb *cb;
371 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
374 if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
377 sc->sc_dma_ch[ch].intr_func = func;
378 sc->sc_dma_ch[ch].intr_arg = arg;
379 cb = sc->sc_dma_ch[ch].cb;
380 cb->info |= INFO_INT_EN;
386 * Setup DMA source parameters
387 * ch - channel number
388 * dreq - hardware DREQ # or BCM_DMA_DREQ_NONE if
389 * source is physical memory
390 * inc_addr - BCM_DMA_INC_ADDR if source address
391 * should be increased after each access or
392 * BCM_DMA_SAME_ADDR if address should remain
394 * width - size of read operation, BCM_DMA_32BIT
395 * for 32bit bursts, BCM_DMA_128BIT for 128 bits
397 * Returns 0 on success, -1 otherwise
400 bcm_dma_setup_src(int ch, int dreq, int inc_addr, int width)
402 struct bcm_dma_softc *sc = bcm_dma_sc;
405 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
408 if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
411 info = sc->sc_dma_ch[ch].cb->info;
412 info &= ~INFO_PERMAP_MASK;
413 info |= (dreq << INFO_PERMAP_SHIFT) & INFO_PERMAP_MASK;
418 info &= ~INFO_S_DREQ;
420 if (width == BCM_DMA_128BIT)
421 info |= INFO_S_WIDTH;
423 info &= ~INFO_S_WIDTH;
425 if (inc_addr == BCM_DMA_INC_ADDR)
430 sc->sc_dma_ch[ch].cb->info = info;
436 * Setup DMA destination parameters
437 * ch - channel number
438 * dreq - hardware DREQ # or BCM_DMA_DREQ_NONE if
439 * destination is physical memory
440 * inc_addr - BCM_DMA_INC_ADDR if source address
441 * should be increased after each access or
442 * BCM_DMA_SAME_ADDR if address should remain
444 * width - size of write operation, BCM_DMA_32BIT
445 * for 32bit bursts, BCM_DMA_128BIT for 128 bits
447 * Returns 0 on success, -1 otherwise
450 bcm_dma_setup_dst(int ch, int dreq, int inc_addr, int width)
452 struct bcm_dma_softc *sc = bcm_dma_sc;
455 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
458 if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
461 info = sc->sc_dma_ch[ch].cb->info;
462 info &= ~INFO_PERMAP_MASK;
463 info |= (dreq << INFO_PERMAP_SHIFT) & INFO_PERMAP_MASK;
468 info &= ~INFO_D_DREQ;
470 if (width == BCM_DMA_128BIT)
471 info |= INFO_D_WIDTH;
473 info &= ~INFO_D_WIDTH;
475 if (inc_addr == BCM_DMA_INC_ADDR)
480 sc->sc_dma_ch[ch].cb->info = info;
487 bcm_dma_cb_dump(struct bcm_dma_cb *cb)
491 printf("INFO: %8.8x ", cb->info);
492 printf("SRC: %8.8x ", cb->src);
493 printf("DST: %8.8x ", cb->dst);
494 printf("LEN: %8.8x ", cb->len);
496 printf("STRIDE: %8.8x ", cb->stride);
497 printf("NEXT: %8.8x ", cb->next);
498 printf("RSVD1: %8.8x ", cb->rsvd1);
499 printf("RSVD2: %8.8x ", cb->rsvd2);
504 bcm_dma_reg_dump(int ch)
506 struct bcm_dma_softc *sc = bcm_dma_sc;
510 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
513 printf("DMA%d: ", ch);
514 for (i = 0; i < MAX_REG; i++) {
515 reg = bus_read_4(sc->sc_mem, BCM_DMA_CH(ch) + i*4);
516 printf("%8.8x ", reg);
523 * Start DMA transaction
524 * ch - channel number
525 * src, dst - source and destination address in
526 * ARM physical memory address space.
527 * len - amount of bytes to be transfered
529 * Returns 0 on success, -1 otherwise
532 bcm_dma_start(int ch, vm_paddr_t src, vm_paddr_t dst, int len)
534 struct bcm_dma_softc *sc = bcm_dma_sc;
535 struct bcm_dma_cb *cb;
537 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
540 if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
543 cb = sc->sc_dma_ch[ch].cb;
544 if (BCM2835_ARM_IS_IO(src))
545 cb->src = IO_TO_VCBUS(src);
547 cb->src = PHYS_TO_VCBUS(src);
548 if (BCM2835_ARM_IS_IO(dst))
549 cb->dst = IO_TO_VCBUS(dst);
551 cb->dst = PHYS_TO_VCBUS(dst);
554 bus_dmamap_sync(sc->sc_dma_tag,
555 sc->sc_dma_ch[ch].dma_map, BUS_DMASYNC_PREWRITE);
557 bus_write_4(sc->sc_mem, BCM_DMA_CBADDR(ch),
558 sc->sc_dma_ch[ch].vc_cb);
559 bus_write_4(sc->sc_mem, BCM_DMA_CS(ch), CS_ACTIVE);
562 bcm_dma_cb_dump(sc->sc_dma_ch[ch].cb);
563 bcm_dma_reg_dump(ch);
570 * Get length requested for DMA transaction
571 * ch - channel number
573 * Returns size of transaction, 0 if channel is invalid
576 bcm_dma_length(int ch)
578 struct bcm_dma_softc *sc = bcm_dma_sc;
579 struct bcm_dma_cb *cb;
581 if (ch < 0 || ch >= BCM_DMA_CH_MAX)
584 if (!(sc->sc_dma_ch[ch].flags & BCM_DMA_CH_USED))
587 cb = sc->sc_dma_ch[ch].cb;
593 bcm_dma_intr(void *arg)
595 struct bcm_dma_softc *sc = bcm_dma_sc;
596 struct bcm_dma_ch *ch = (struct bcm_dma_ch *)arg;
600 cs = bus_read_4(sc->sc_mem, BCM_DMA_CS(ch->ch));
602 if (!(cs & (CS_INT | CS_ERR)))
606 if (!(ch->flags & BCM_DMA_CH_USED)) {
607 device_printf(sc->sc_dev,
608 "unused DMA intr CH=%d, CS=%x\n", ch->ch, cs);
613 debug = bus_read_4(sc->sc_mem, BCM_DMA_DEBUG(ch->ch));
614 device_printf(sc->sc_dev, "DMA error %d on CH%d\n",
615 debug & DEBUG_ERROR_MASK, ch->ch);
616 bus_write_4(sc->sc_mem, BCM_DMA_DEBUG(ch->ch),
617 debug & DEBUG_ERROR_MASK);
618 bcm_dma_reset(sc->sc_dev, ch->ch);
622 /* acknowledge interrupt */
623 bus_write_4(sc->sc_mem, BCM_DMA_CS(ch->ch),
626 /* Prepare for possible access to len field */
627 bus_dmamap_sync(sc->sc_dma_tag, ch->dma_map,
628 BUS_DMASYNC_POSTWRITE);
630 /* save callback function and argument */
632 ch->intr_func(ch->ch, ch->intr_arg);
637 bcm_dma_probe(device_t dev)
640 if (!ofw_bus_status_okay(dev))
643 if (!ofw_bus_is_compatible(dev, "broadcom,bcm2835-dma"))
646 device_set_desc(dev, "BCM2835 DMA Controller");
647 return (BUS_PROBE_DEFAULT);
651 bcm_dma_attach(device_t dev)
653 struct bcm_dma_softc *sc = device_get_softc(dev);
662 for (i = 0; i < BCM_DMA_CH_MAX; i++) {
663 sc->sc_irq[i] = NULL;
664 sc->sc_intrhand[i] = NULL;
669 sc->sc_mem = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
670 if (sc->sc_mem == NULL) {
671 device_printf(dev, "could not allocate memory resource\n");
675 /* IRQ DMA0 - DMA11 XXX NOT USE DMA12(spurious?) */
676 for (rid = 0; rid < BCM_DMA_CH_MAX; rid++) {
677 sc->sc_irq[rid] = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
679 if (sc->sc_irq[rid] == NULL) {
680 device_printf(dev, "cannot allocate interrupt\n");
684 if (bus_setup_intr(dev, sc->sc_irq[rid], INTR_TYPE_MISC | INTR_MPSAFE,
685 NULL, bcm_dma_intr, &sc->sc_dma_ch[rid],
686 &sc->sc_intrhand[rid])) {
687 device_printf(dev, "cannot setup interrupt handler\n");
693 mtx_init(&sc->sc_mtx, "bcmdma", "bcmdma", MTX_DEF);
696 err = bcm_dma_init(dev);
704 bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem);
706 for (i = 0; i < BCM_DMA_CH_MAX; i++) {
707 if (sc->sc_intrhand[i])
708 bus_teardown_intr(dev, sc->sc_irq[i], sc->sc_intrhand[i]);
710 bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq[i]);
716 static device_method_t bcm_dma_methods[] = {
717 DEVMETHOD(device_probe, bcm_dma_probe),
718 DEVMETHOD(device_attach, bcm_dma_attach),
722 static driver_t bcm_dma_driver = {
725 sizeof(struct bcm_dma_softc),
728 static devclass_t bcm_dma_devclass;
730 DRIVER_MODULE(bcm_dma, simplebus, bcm_dma_driver, bcm_dma_devclass, 0, 0);
731 MODULE_VERSION(bcm_dma, 1);