[PATCH] Driver Core: remove driver model detach_state
[linux-2.6/verdex.git] / arch / mips / au1000 / common / dbdma.c
blobadfc3172aace51c06a9ce36272d2c953a0607b66
1 /*
3 * BRIEF MODULE DESCRIPTION
4 * The Descriptor Based DMA channel manager that first appeared
5 * on the Au1550. I started with dma.c, but I think all that is
6 * left is this initial comment :-)
8 * Copyright 2004 Embedded Edge, LLC
9 * dan@embeddededge.com
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version.
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
19 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
22 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
23 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 * You should have received a copy of the GNU General Public License along
28 * with this program; if not, write to the Free Software Foundation, Inc.,
29 * 675 Mass Ave, Cambridge, MA 02139, USA.
32 #include <linux/config.h>
33 #include <linux/kernel.h>
34 #include <linux/errno.h>
35 #include <linux/sched.h>
36 #include <linux/slab.h>
37 #include <linux/spinlock.h>
38 #include <linux/string.h>
39 #include <linux/delay.h>
40 #include <linux/interrupt.h>
41 #include <asm/mach-au1x00/au1000.h>
42 #include <asm/mach-au1x00/au1xxx_dbdma.h>
43 #include <asm/system.h>
45 #if defined(CONFIG_SOC_AU1550) || defined(CONFIG_SOC_AU1200)
48 * The Descriptor Based DMA supports up to 16 channels.
50 * There are 32 devices defined. We keep an internal structure
51 * of devices using these channels, along with additional
52 * information.
54 * We allocate the descriptors and allow access to them through various
55 * functions. The drivers allocate the data buffers and assign them
56 * to the descriptors.
58 static DEFINE_SPINLOCK(au1xxx_dbdma_spin_lock);
60 /* I couldn't find a macro that did this......
62 #define ALIGN_ADDR(x, a) ((((u32)(x)) + (a-1)) & ~(a-1))
64 static volatile dbdma_global_t *dbdma_gptr = (dbdma_global_t *)DDMA_GLOBAL_BASE;
65 static int dbdma_initialized;
66 static void au1xxx_dbdma_init(void);
68 typedef struct dbdma_device_table {
69 u32 dev_id;
70 u32 dev_flags;
71 u32 dev_tsize;
72 u32 dev_devwidth;
73 u32 dev_physaddr; /* If FIFO */
74 u32 dev_intlevel;
75 u32 dev_intpolarity;
76 } dbdev_tab_t;
78 typedef struct dbdma_chan_config {
79 u32 chan_flags;
80 u32 chan_index;
81 dbdev_tab_t *chan_src;
82 dbdev_tab_t *chan_dest;
83 au1x_dma_chan_t *chan_ptr;
84 au1x_ddma_desc_t *chan_desc_base;
85 au1x_ddma_desc_t *get_ptr, *put_ptr, *cur_ptr;
86 void *chan_callparam;
87 void (*chan_callback)(int, void *, struct pt_regs *);
88 } chan_tab_t;
90 #define DEV_FLAGS_INUSE (1 << 0)
91 #define DEV_FLAGS_ANYUSE (1 << 1)
92 #define DEV_FLAGS_OUT (1 << 2)
93 #define DEV_FLAGS_IN (1 << 3)
95 static dbdev_tab_t dbdev_tab[] = {
96 #ifdef CONFIG_SOC_AU1550
97 /* UARTS */
98 { DSCR_CMD0_UART0_TX, DEV_FLAGS_OUT, 0, 8, 0x11100004, 0, 0 },
99 { DSCR_CMD0_UART0_RX, DEV_FLAGS_IN, 0, 8, 0x11100000, 0, 0 },
100 { DSCR_CMD0_UART3_TX, DEV_FLAGS_OUT, 0, 8, 0x11400004, 0, 0 },
101 { DSCR_CMD0_UART3_RX, DEV_FLAGS_IN, 0, 8, 0x11400000, 0, 0 },
103 /* EXT DMA */
104 { DSCR_CMD0_DMA_REQ0, 0, 0, 0, 0x00000000, 0, 0 },
105 { DSCR_CMD0_DMA_REQ1, 0, 0, 0, 0x00000000, 0, 0 },
106 { DSCR_CMD0_DMA_REQ2, 0, 0, 0, 0x00000000, 0, 0 },
107 { DSCR_CMD0_DMA_REQ3, 0, 0, 0, 0x00000000, 0, 0 },
109 /* USB DEV */
110 { DSCR_CMD0_USBDEV_RX0, DEV_FLAGS_IN, 4, 8, 0x10200000, 0, 0 },
111 { DSCR_CMD0_USBDEV_TX0, DEV_FLAGS_OUT, 4, 8, 0x10200004, 0, 0 },
112 { DSCR_CMD0_USBDEV_TX1, DEV_FLAGS_OUT, 4, 8, 0x10200008, 0, 0 },
113 { DSCR_CMD0_USBDEV_TX2, DEV_FLAGS_OUT, 4, 8, 0x1020000c, 0, 0 },
114 { DSCR_CMD0_USBDEV_RX3, DEV_FLAGS_IN, 4, 8, 0x10200010, 0, 0 },
115 { DSCR_CMD0_USBDEV_RX4, DEV_FLAGS_IN, 4, 8, 0x10200014, 0, 0 },
117 /* PSC 0 */
118 { DSCR_CMD0_PSC0_TX, DEV_FLAGS_OUT, 0, 0, 0x11a0001c, 0, 0 },
119 { DSCR_CMD0_PSC0_RX, DEV_FLAGS_IN, 0, 0, 0x11a0001c, 0, 0 },
121 /* PSC 1 */
122 { DSCR_CMD0_PSC1_TX, DEV_FLAGS_OUT, 0, 0, 0x11b0001c, 0, 0 },
123 { DSCR_CMD0_PSC1_RX, DEV_FLAGS_IN, 0, 0, 0x11b0001c, 0, 0 },
125 /* PSC 2 */
126 { DSCR_CMD0_PSC2_TX, DEV_FLAGS_OUT, 0, 0, 0x10a0001c, 0, 0 },
127 { DSCR_CMD0_PSC2_RX, DEV_FLAGS_IN, 0, 0, 0x10a0001c, 0, 0 },
129 /* PSC 3 */
130 { DSCR_CMD0_PSC3_TX, DEV_FLAGS_OUT, 0, 0, 0x10b0001c, 0, 0 },
131 { DSCR_CMD0_PSC3_RX, DEV_FLAGS_IN, 0, 0, 0x10b0001c, 0, 0 },
133 { DSCR_CMD0_PCI_WRITE, 0, 0, 0, 0x00000000, 0, 0 }, /* PCI */
134 { DSCR_CMD0_NAND_FLASH, 0, 0, 0, 0x00000000, 0, 0 }, /* NAND */
136 /* MAC 0 */
137 { DSCR_CMD0_MAC0_RX, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
138 { DSCR_CMD0_MAC0_TX, DEV_FLAGS_OUT, 0, 0, 0x00000000, 0, 0 },
140 /* MAC 1 */
141 { DSCR_CMD0_MAC1_RX, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
142 { DSCR_CMD0_MAC1_TX, DEV_FLAGS_OUT, 0, 0, 0x00000000, 0, 0 },
144 #endif /* CONFIG_SOC_AU1550 */
146 #ifdef CONFIG_SOC_AU1200
147 { DSCR_CMD0_UART0_TX, DEV_FLAGS_OUT, 0, 8, 0x11100004, 0, 0 },
148 { DSCR_CMD0_UART0_RX, DEV_FLAGS_IN, 0, 8, 0x11100000, 0, 0 },
149 { DSCR_CMD0_UART1_TX, DEV_FLAGS_OUT, 0, 8, 0x11200004, 0, 0 },
150 { DSCR_CMD0_UART1_RX, DEV_FLAGS_IN, 0, 8, 0x11200000, 0, 0 },
152 { DSCR_CMD0_DMA_REQ0, 0, 0, 0, 0x00000000, 0, 0 },
153 { DSCR_CMD0_DMA_REQ1, 0, 0, 0, 0x00000000, 0, 0 },
155 { DSCR_CMD0_MAE_BE, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
156 { DSCR_CMD0_MAE_FE, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
157 { DSCR_CMD0_MAE_BOTH, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
158 { DSCR_CMD0_LCD, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
160 { DSCR_CMD0_SDMS_TX0, DEV_FLAGS_OUT, 0, 0, 0x00000000, 0, 0 },
161 { DSCR_CMD0_SDMS_RX0, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
162 { DSCR_CMD0_SDMS_TX1, DEV_FLAGS_OUT, 0, 0, 0x00000000, 0, 0 },
163 { DSCR_CMD0_SDMS_RX1, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
165 { DSCR_CMD0_AES_TX, DEV_FLAGS_OUT, 0, 0, 0x00000000, 0, 0 },
166 { DSCR_CMD0_AES_RX, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
168 { DSCR_CMD0_PSC0_TX, DEV_FLAGS_OUT, 0, 0, 0x11a0001c, 0, 0 },
169 { DSCR_CMD0_PSC0_RX, DEV_FLAGS_IN, 0, 0, 0x11a0001c, 0, 0 },
170 { DSCR_CMD0_PSC0_SYNC, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
172 { DSCR_CMD0_PSC1_TX, DEV_FLAGS_OUT, 0, 0, 0x11b0001c, 0, 0 },
173 { DSCR_CMD0_PSC1_RX, DEV_FLAGS_IN, 0, 0, 0x11b0001c, 0, 0 },
174 { DSCR_CMD0_PSC1_SYNC, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
176 { DSCR_CMD0_CIM_RXA, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
177 { DSCR_CMD0_CIM_RXB, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
178 { DSCR_CMD0_CIM_RXC, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
179 { DSCR_CMD0_CIM_SYNC, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
181 { DSCR_CMD0_NAND_FLASH, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
183 #endif // CONFIG_SOC_AU1200
185 { DSCR_CMD0_THROTTLE, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
186 { DSCR_CMD0_ALWAYS, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
189 #define DBDEV_TAB_SIZE (sizeof(dbdev_tab) / sizeof(dbdev_tab_t))
191 static chan_tab_t *chan_tab_ptr[NUM_DBDMA_CHANS];
193 static dbdev_tab_t *
194 find_dbdev_id (u32 id)
196 int i;
197 dbdev_tab_t *p;
198 for (i = 0; i < DBDEV_TAB_SIZE; ++i) {
199 p = &dbdev_tab[i];
200 if (p->dev_id == id)
201 return p;
203 return NULL;
206 /* Allocate a channel and return a non-zero descriptor if successful.
209 au1xxx_dbdma_chan_alloc(u32 srcid, u32 destid,
210 void (*callback)(int, void *, struct pt_regs *), void *callparam)
212 unsigned long flags;
213 u32 used, chan, rv;
214 u32 dcp;
215 int i;
216 dbdev_tab_t *stp, *dtp;
217 chan_tab_t *ctp;
218 volatile au1x_dma_chan_t *cp;
220 /* We do the intialization on the first channel allocation.
221 * We have to wait because of the interrupt handler initialization
222 * which can't be done successfully during board set up.
224 if (!dbdma_initialized)
225 au1xxx_dbdma_init();
226 dbdma_initialized = 1;
228 if ((srcid > DSCR_NDEV_IDS) || (destid > DSCR_NDEV_IDS))
229 return 0;
231 if ((stp = find_dbdev_id(srcid)) == NULL) return 0;
232 if ((dtp = find_dbdev_id(destid)) == NULL) return 0;
234 used = 0;
235 rv = 0;
237 /* Check to see if we can get both channels.
239 spin_lock_irqsave(&au1xxx_dbdma_spin_lock, flags);
240 if (!(stp->dev_flags & DEV_FLAGS_INUSE) ||
241 (stp->dev_flags & DEV_FLAGS_ANYUSE)) {
242 /* Got source */
243 stp->dev_flags |= DEV_FLAGS_INUSE;
244 if (!(dtp->dev_flags & DEV_FLAGS_INUSE) ||
245 (dtp->dev_flags & DEV_FLAGS_ANYUSE)) {
246 /* Got destination */
247 dtp->dev_flags |= DEV_FLAGS_INUSE;
249 else {
250 /* Can't get dest. Release src.
252 stp->dev_flags &= ~DEV_FLAGS_INUSE;
253 used++;
256 else {
257 used++;
259 spin_unlock_irqrestore(&au1xxx_dbdma_spin_lock, flags);
261 if (!used) {
262 /* Let's see if we can allocate a channel for it.
264 ctp = NULL;
265 chan = 0;
266 spin_lock_irqsave(&au1xxx_dbdma_spin_lock, flags);
267 for (i=0; i<NUM_DBDMA_CHANS; i++) {
268 if (chan_tab_ptr[i] == NULL) {
269 /* If kmalloc fails, it is caught below same
270 * as a channel not available.
272 ctp = kmalloc(sizeof(chan_tab_t), GFP_KERNEL);
273 chan_tab_ptr[i] = ctp;
274 ctp->chan_index = chan = i;
275 break;
278 spin_unlock_irqrestore(&au1xxx_dbdma_spin_lock, flags);
280 if (ctp != NULL) {
281 memset(ctp, 0, sizeof(chan_tab_t));
282 dcp = DDMA_CHANNEL_BASE;
283 dcp += (0x0100 * chan);
284 ctp->chan_ptr = (au1x_dma_chan_t *)dcp;
285 cp = (volatile au1x_dma_chan_t *)dcp;
286 ctp->chan_src = stp;
287 ctp->chan_dest = dtp;
288 ctp->chan_callback = callback;
289 ctp->chan_callparam = callparam;
291 /* Initialize channel configuration.
293 i = 0;
294 if (stp->dev_intlevel)
295 i |= DDMA_CFG_SED;
296 if (stp->dev_intpolarity)
297 i |= DDMA_CFG_SP;
298 if (dtp->dev_intlevel)
299 i |= DDMA_CFG_DED;
300 if (dtp->dev_intpolarity)
301 i |= DDMA_CFG_DP;
302 cp->ddma_cfg = i;
303 au_sync();
305 /* Return a non-zero value that can be used to
306 * find the channel information in subsequent
307 * operations.
309 rv = (u32)(&chan_tab_ptr[chan]);
311 else {
312 /* Release devices.
314 stp->dev_flags &= ~DEV_FLAGS_INUSE;
315 dtp->dev_flags &= ~DEV_FLAGS_INUSE;
318 return rv;
321 /* Set the device width if source or destination is a FIFO.
322 * Should be 8, 16, or 32 bits.
325 au1xxx_dbdma_set_devwidth(u32 chanid, int bits)
327 u32 rv;
328 chan_tab_t *ctp;
329 dbdev_tab_t *stp, *dtp;
331 ctp = *((chan_tab_t **)chanid);
332 stp = ctp->chan_src;
333 dtp = ctp->chan_dest;
334 rv = 0;
336 if (stp->dev_flags & DEV_FLAGS_IN) { /* Source in fifo */
337 rv = stp->dev_devwidth;
338 stp->dev_devwidth = bits;
340 if (dtp->dev_flags & DEV_FLAGS_OUT) { /* Destination out fifo */
341 rv = dtp->dev_devwidth;
342 dtp->dev_devwidth = bits;
345 return rv;
348 /* Allocate a descriptor ring, initializing as much as possible.
351 au1xxx_dbdma_ring_alloc(u32 chanid, int entries)
353 int i;
354 u32 desc_base, srcid, destid;
355 u32 cmd0, cmd1, src1, dest1;
356 u32 src0, dest0;
357 chan_tab_t *ctp;
358 dbdev_tab_t *stp, *dtp;
359 au1x_ddma_desc_t *dp;
361 /* I guess we could check this to be within the
362 * range of the table......
364 ctp = *((chan_tab_t **)chanid);
365 stp = ctp->chan_src;
366 dtp = ctp->chan_dest;
368 /* The descriptors must be 32-byte aligned. There is a
369 * possibility the allocation will give us such an address,
370 * and if we try that first we are likely to not waste larger
371 * slabs of memory.
373 desc_base = (u32)kmalloc(entries * sizeof(au1x_ddma_desc_t), GFP_KERNEL);
374 if (desc_base == 0)
375 return 0;
377 if (desc_base & 0x1f) {
378 /* Lost....do it again, allocate extra, and round
379 * the address base.
381 kfree((const void *)desc_base);
382 i = entries * sizeof(au1x_ddma_desc_t);
383 i += (sizeof(au1x_ddma_desc_t) - 1);
384 if ((desc_base = (u32)kmalloc(i, GFP_KERNEL)) == 0)
385 return 0;
387 desc_base = ALIGN_ADDR(desc_base, sizeof(au1x_ddma_desc_t));
389 dp = (au1x_ddma_desc_t *)desc_base;
391 /* Keep track of the base descriptor.
393 ctp->chan_desc_base = dp;
395 /* Initialize the rings with as much information as we know.
397 srcid = stp->dev_id;
398 destid = dtp->dev_id;
400 cmd0 = cmd1 = src1 = dest1 = 0;
401 src0 = dest0 = 0;
403 cmd0 |= DSCR_CMD0_SID(srcid);
404 cmd0 |= DSCR_CMD0_DID(destid);
405 cmd0 |= DSCR_CMD0_IE | DSCR_CMD0_CV;
406 cmd0 |= DSCR_CMD0_ST(DSCR_CMD0_ST_CURRENT);
408 switch (stp->dev_devwidth) {
409 case 8:
410 cmd0 |= DSCR_CMD0_SW(DSCR_CMD0_BYTE);
411 break;
412 case 16:
413 cmd0 |= DSCR_CMD0_SW(DSCR_CMD0_HALFWORD);
414 break;
415 case 32:
416 default:
417 cmd0 |= DSCR_CMD0_SW(DSCR_CMD0_WORD);
418 break;
421 switch (dtp->dev_devwidth) {
422 case 8:
423 cmd0 |= DSCR_CMD0_DW(DSCR_CMD0_BYTE);
424 break;
425 case 16:
426 cmd0 |= DSCR_CMD0_DW(DSCR_CMD0_HALFWORD);
427 break;
428 case 32:
429 default:
430 cmd0 |= DSCR_CMD0_DW(DSCR_CMD0_WORD);
431 break;
434 /* If the device is marked as an in/out FIFO, ensure it is
435 * set non-coherent.
437 if (stp->dev_flags & DEV_FLAGS_IN)
438 cmd0 |= DSCR_CMD0_SN; /* Source in fifo */
439 if (dtp->dev_flags & DEV_FLAGS_OUT)
440 cmd0 |= DSCR_CMD0_DN; /* Destination out fifo */
442 /* Set up source1. For now, assume no stride and increment.
443 * A channel attribute update can change this later.
445 switch (stp->dev_tsize) {
446 case 1:
447 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE1);
448 break;
449 case 2:
450 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE2);
451 break;
452 case 4:
453 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE4);
454 break;
455 case 8:
456 default:
457 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE8);
458 break;
461 /* If source input is fifo, set static address.
463 if (stp->dev_flags & DEV_FLAGS_IN) {
464 src0 = stp->dev_physaddr;
465 src1 |= DSCR_SRC1_SAM(DSCR_xAM_STATIC);
468 /* Set up dest1. For now, assume no stride and increment.
469 * A channel attribute update can change this later.
471 switch (dtp->dev_tsize) {
472 case 1:
473 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE1);
474 break;
475 case 2:
476 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE2);
477 break;
478 case 4:
479 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE4);
480 break;
481 case 8:
482 default:
483 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE8);
484 break;
487 /* If destination output is fifo, set static address.
489 if (dtp->dev_flags & DEV_FLAGS_OUT) {
490 dest0 = dtp->dev_physaddr;
491 dest1 |= DSCR_DEST1_DAM(DSCR_xAM_STATIC);
494 for (i=0; i<entries; i++) {
495 dp->dscr_cmd0 = cmd0;
496 dp->dscr_cmd1 = cmd1;
497 dp->dscr_source0 = src0;
498 dp->dscr_source1 = src1;
499 dp->dscr_dest0 = dest0;
500 dp->dscr_dest1 = dest1;
501 dp->dscr_stat = 0;
502 dp->dscr_nxtptr = DSCR_NXTPTR(virt_to_phys(dp + 1));
503 dp++;
506 /* Make last descrptor point to the first.
508 dp--;
509 dp->dscr_nxtptr = DSCR_NXTPTR(virt_to_phys(ctp->chan_desc_base));
510 ctp->get_ptr = ctp->put_ptr = ctp->cur_ptr = ctp->chan_desc_base;
512 return (u32)(ctp->chan_desc_base);
515 /* Put a source buffer into the DMA ring.
516 * This updates the source pointer and byte count. Normally used
517 * for memory to fifo transfers.
520 au1xxx_dbdma_put_source(u32 chanid, void *buf, int nbytes)
522 chan_tab_t *ctp;
523 au1x_ddma_desc_t *dp;
525 /* I guess we could check this to be within the
526 * range of the table......
528 ctp = *((chan_tab_t **)chanid);
530 /* We should have multiple callers for a particular channel,
531 * an interrupt doesn't affect this pointer nor the descriptor,
532 * so no locking should be needed.
534 dp = ctp->put_ptr;
536 /* If the descriptor is valid, we are way ahead of the DMA
537 * engine, so just return an error condition.
539 if (dp->dscr_cmd0 & DSCR_CMD0_V) {
540 return 0;
543 /* Load up buffer address and byte count.
545 dp->dscr_source0 = virt_to_phys(buf);
546 dp->dscr_cmd1 = nbytes;
547 dp->dscr_cmd0 |= DSCR_CMD0_V; /* Let it rip */
548 ctp->chan_ptr->ddma_dbell = 0xffffffff; /* Make it go */
550 /* Get next descriptor pointer.
552 ctp->put_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
554 /* return something not zero.
556 return nbytes;
559 /* Put a destination buffer into the DMA ring.
560 * This updates the destination pointer and byte count. Normally used
561 * to place an empty buffer into the ring for fifo to memory transfers.
564 au1xxx_dbdma_put_dest(u32 chanid, void *buf, int nbytes)
566 chan_tab_t *ctp;
567 au1x_ddma_desc_t *dp;
569 /* I guess we could check this to be within the
570 * range of the table......
572 ctp = *((chan_tab_t **)chanid);
574 /* We should have multiple callers for a particular channel,
575 * an interrupt doesn't affect this pointer nor the descriptor,
576 * so no locking should be needed.
578 dp = ctp->put_ptr;
580 /* If the descriptor is valid, we are way ahead of the DMA
581 * engine, so just return an error condition.
583 if (dp->dscr_cmd0 & DSCR_CMD0_V)
584 return 0;
586 /* Load up buffer address and byte count.
588 dp->dscr_dest0 = virt_to_phys(buf);
589 dp->dscr_cmd1 = nbytes;
590 dp->dscr_cmd0 |= DSCR_CMD0_V; /* Let it rip */
592 /* Get next descriptor pointer.
594 ctp->put_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
596 /* return something not zero.
598 return nbytes;
601 /* Get a destination buffer into the DMA ring.
602 * Normally used to get a full buffer from the ring during fifo
603 * to memory transfers. This does not set the valid bit, you will
604 * have to put another destination buffer to keep the DMA going.
607 au1xxx_dbdma_get_dest(u32 chanid, void **buf, int *nbytes)
609 chan_tab_t *ctp;
610 au1x_ddma_desc_t *dp;
611 u32 rv;
613 /* I guess we could check this to be within the
614 * range of the table......
616 ctp = *((chan_tab_t **)chanid);
618 /* We should have multiple callers for a particular channel,
619 * an interrupt doesn't affect this pointer nor the descriptor,
620 * so no locking should be needed.
622 dp = ctp->get_ptr;
624 /* If the descriptor is valid, we are way ahead of the DMA
625 * engine, so just return an error condition.
627 if (dp->dscr_cmd0 & DSCR_CMD0_V)
628 return 0;
630 /* Return buffer address and byte count.
632 *buf = (void *)(phys_to_virt(dp->dscr_dest0));
633 *nbytes = dp->dscr_cmd1;
634 rv = dp->dscr_stat;
636 /* Get next descriptor pointer.
638 ctp->get_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
640 /* return something not zero.
642 return rv;
645 void
646 au1xxx_dbdma_stop(u32 chanid)
648 chan_tab_t *ctp;
649 volatile au1x_dma_chan_t *cp;
650 int halt_timeout = 0;
652 ctp = *((chan_tab_t **)chanid);
654 cp = ctp->chan_ptr;
655 cp->ddma_cfg &= ~DDMA_CFG_EN; /* Disable channel */
656 au_sync();
657 while (!(cp->ddma_stat & DDMA_STAT_H)) {
658 udelay(1);
659 halt_timeout++;
660 if (halt_timeout > 100) {
661 printk("warning: DMA channel won't halt\n");
662 break;
665 /* clear current desc valid and doorbell */
666 cp->ddma_stat |= (DDMA_STAT_DB | DDMA_STAT_V);
667 au_sync();
670 /* Start using the current descriptor pointer. If the dbdma encounters
671 * a not valid descriptor, it will stop. In this case, we can just
672 * continue by adding a buffer to the list and starting again.
674 void
675 au1xxx_dbdma_start(u32 chanid)
677 chan_tab_t *ctp;
678 volatile au1x_dma_chan_t *cp;
680 ctp = *((chan_tab_t **)chanid);
682 cp = ctp->chan_ptr;
683 cp->ddma_desptr = virt_to_phys(ctp->cur_ptr);
684 cp->ddma_cfg |= DDMA_CFG_EN; /* Enable channel */
685 au_sync();
686 cp->ddma_dbell = 0xffffffff; /* Make it go */
687 au_sync();
690 void
691 au1xxx_dbdma_reset(u32 chanid)
693 chan_tab_t *ctp;
694 au1x_ddma_desc_t *dp;
696 au1xxx_dbdma_stop(chanid);
698 ctp = *((chan_tab_t **)chanid);
699 ctp->get_ptr = ctp->put_ptr = ctp->cur_ptr = ctp->chan_desc_base;
701 /* Run through the descriptors and reset the valid indicator.
703 dp = ctp->chan_desc_base;
705 do {
706 dp->dscr_cmd0 &= ~DSCR_CMD0_V;
707 dp = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
708 } while (dp != ctp->chan_desc_base);
712 au1xxx_get_dma_residue(u32 chanid)
714 chan_tab_t *ctp;
715 volatile au1x_dma_chan_t *cp;
716 u32 rv;
718 ctp = *((chan_tab_t **)chanid);
719 cp = ctp->chan_ptr;
721 /* This is only valid if the channel is stopped.
723 rv = cp->ddma_bytecnt;
724 au_sync();
726 return rv;
729 void
730 au1xxx_dbdma_chan_free(u32 chanid)
732 chan_tab_t *ctp;
733 dbdev_tab_t *stp, *dtp;
735 ctp = *((chan_tab_t **)chanid);
736 stp = ctp->chan_src;
737 dtp = ctp->chan_dest;
739 au1xxx_dbdma_stop(chanid);
741 if (ctp->chan_desc_base != NULL)
742 kfree(ctp->chan_desc_base);
744 stp->dev_flags &= ~DEV_FLAGS_INUSE;
745 dtp->dev_flags &= ~DEV_FLAGS_INUSE;
746 chan_tab_ptr[ctp->chan_index] = NULL;
748 kfree(ctp);
751 static irqreturn_t
752 dbdma_interrupt(int irq, void *dev_id, struct pt_regs *regs)
754 u32 intstat;
755 u32 chan_index;
756 chan_tab_t *ctp;
757 au1x_ddma_desc_t *dp;
758 volatile au1x_dma_chan_t *cp;
760 intstat = dbdma_gptr->ddma_intstat;
761 au_sync();
762 chan_index = au_ffs(intstat) - 1;
764 ctp = chan_tab_ptr[chan_index];
765 cp = ctp->chan_ptr;
766 dp = ctp->cur_ptr;
768 /* Reset interrupt.
770 cp->ddma_irq = 0;
771 au_sync();
773 if (ctp->chan_callback)
774 (ctp->chan_callback)(irq, ctp->chan_callparam, regs);
776 ctp->cur_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
778 return IRQ_HANDLED;
781 static void
782 au1xxx_dbdma_init(void)
784 dbdma_gptr->ddma_config = 0;
785 dbdma_gptr->ddma_throttle = 0;
786 dbdma_gptr->ddma_inten = 0xffff;
787 au_sync();
789 if (request_irq(AU1550_DDMA_INT, dbdma_interrupt, SA_INTERRUPT,
790 "Au1xxx dbdma", (void *)dbdma_gptr))
791 printk("Can't get 1550 dbdma irq");
794 void
795 au1xxx_dbdma_dump(u32 chanid)
797 chan_tab_t *ctp;
798 au1x_ddma_desc_t *dp;
799 dbdev_tab_t *stp, *dtp;
800 volatile au1x_dma_chan_t *cp;
802 ctp = *((chan_tab_t **)chanid);
803 stp = ctp->chan_src;
804 dtp = ctp->chan_dest;
805 cp = ctp->chan_ptr;
807 printk("Chan %x, stp %x (dev %d) dtp %x (dev %d) \n",
808 (u32)ctp, (u32)stp, stp - dbdev_tab, (u32)dtp, dtp - dbdev_tab);
809 printk("desc base %x, get %x, put %x, cur %x\n",
810 (u32)(ctp->chan_desc_base), (u32)(ctp->get_ptr),
811 (u32)(ctp->put_ptr), (u32)(ctp->cur_ptr));
813 printk("dbdma chan %x\n", (u32)cp);
814 printk("cfg %08x, desptr %08x, statptr %08x\n",
815 cp->ddma_cfg, cp->ddma_desptr, cp->ddma_statptr);
816 printk("dbell %08x, irq %08x, stat %08x, bytecnt %08x\n",
817 cp->ddma_dbell, cp->ddma_irq, cp->ddma_stat, cp->ddma_bytecnt);
820 /* Run through the descriptors
822 dp = ctp->chan_desc_base;
824 do {
825 printk("dp %08x, cmd0 %08x, cmd1 %08x\n",
826 (u32)dp, dp->dscr_cmd0, dp->dscr_cmd1);
827 printk("src0 %08x, src1 %08x, dest0 %08x\n",
828 dp->dscr_source0, dp->dscr_source1, dp->dscr_dest0);
829 printk("dest1 %08x, stat %08x, nxtptr %08x\n",
830 dp->dscr_dest1, dp->dscr_stat, dp->dscr_nxtptr);
831 dp = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
832 } while (dp != ctp->chan_desc_base);
835 #endif /* defined(CONFIG_SOC_AU1550) || defined(CONFIG_SOC_AU1200) */