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
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.
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 <linux/module.h>
42 #include <asm/mach-au1x00/au1000.h>
43 #include <asm/mach-au1x00/au1xxx_dbdma.h>
44 #include <asm/system.h>
47 #if defined(CONFIG_SOC_AU1550) || defined(CONFIG_SOC_AU1200)
50 * The Descriptor Based DMA supports up to 16 channels.
52 * There are 32 devices defined. We keep an internal structure
53 * of devices using these channels, along with additional
56 * We allocate the descriptors and allow access to them through various
57 * functions. The drivers allocate the data buffers and assign them
60 static DEFINE_SPINLOCK(au1xxx_dbdma_spin_lock);
62 /* I couldn't find a macro that did this......
64 #define ALIGN_ADDR(x, a) ((((u32)(x)) + (a-1)) & ~(a-1))
66 static dbdma_global_t *dbdma_gptr = (dbdma_global_t *)DDMA_GLOBAL_BASE;
67 static int dbdma_initialized=0;
68 static void au1xxx_dbdma_init(void);
70 static dbdev_tab_t dbdev_tab[] = {
71 #ifdef CONFIG_SOC_AU1550
73 { DSCR_CMD0_UART0_TX, DEV_FLAGS_OUT, 0, 8, 0x11100004, 0, 0 },
74 { DSCR_CMD0_UART0_RX, DEV_FLAGS_IN, 0, 8, 0x11100000, 0, 0 },
75 { DSCR_CMD0_UART3_TX, DEV_FLAGS_OUT, 0, 8, 0x11400004, 0, 0 },
76 { DSCR_CMD0_UART3_RX, DEV_FLAGS_IN, 0, 8, 0x11400000, 0, 0 },
79 { DSCR_CMD0_DMA_REQ0, 0, 0, 0, 0x00000000, 0, 0 },
80 { DSCR_CMD0_DMA_REQ1, 0, 0, 0, 0x00000000, 0, 0 },
81 { DSCR_CMD0_DMA_REQ2, 0, 0, 0, 0x00000000, 0, 0 },
82 { DSCR_CMD0_DMA_REQ3, 0, 0, 0, 0x00000000, 0, 0 },
85 { DSCR_CMD0_USBDEV_RX0, DEV_FLAGS_IN, 4, 8, 0x10200000, 0, 0 },
86 { DSCR_CMD0_USBDEV_TX0, DEV_FLAGS_OUT, 4, 8, 0x10200004, 0, 0 },
87 { DSCR_CMD0_USBDEV_TX1, DEV_FLAGS_OUT, 4, 8, 0x10200008, 0, 0 },
88 { DSCR_CMD0_USBDEV_TX2, DEV_FLAGS_OUT, 4, 8, 0x1020000c, 0, 0 },
89 { DSCR_CMD0_USBDEV_RX3, DEV_FLAGS_IN, 4, 8, 0x10200010, 0, 0 },
90 { DSCR_CMD0_USBDEV_RX4, DEV_FLAGS_IN, 4, 8, 0x10200014, 0, 0 },
93 { DSCR_CMD0_PSC0_TX, DEV_FLAGS_OUT, 0, 0, 0x11a0001c, 0, 0 },
94 { DSCR_CMD0_PSC0_RX, DEV_FLAGS_IN, 0, 0, 0x11a0001c, 0, 0 },
97 { DSCR_CMD0_PSC1_TX, DEV_FLAGS_OUT, 0, 0, 0x11b0001c, 0, 0 },
98 { DSCR_CMD0_PSC1_RX, DEV_FLAGS_IN, 0, 0, 0x11b0001c, 0, 0 },
101 { DSCR_CMD0_PSC2_TX, DEV_FLAGS_OUT, 0, 0, 0x10a0001c, 0, 0 },
102 { DSCR_CMD0_PSC2_RX, DEV_FLAGS_IN, 0, 0, 0x10a0001c, 0, 0 },
105 { DSCR_CMD0_PSC3_TX, DEV_FLAGS_OUT, 0, 0, 0x10b0001c, 0, 0 },
106 { DSCR_CMD0_PSC3_RX, DEV_FLAGS_IN, 0, 0, 0x10b0001c, 0, 0 },
108 { DSCR_CMD0_PCI_WRITE, 0, 0, 0, 0x00000000, 0, 0 }, /* PCI */
109 { DSCR_CMD0_NAND_FLASH, 0, 0, 0, 0x00000000, 0, 0 }, /* NAND */
112 { DSCR_CMD0_MAC0_RX, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
113 { DSCR_CMD0_MAC0_TX, DEV_FLAGS_OUT, 0, 0, 0x00000000, 0, 0 },
116 { DSCR_CMD0_MAC1_RX, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
117 { DSCR_CMD0_MAC1_TX, DEV_FLAGS_OUT, 0, 0, 0x00000000, 0, 0 },
119 #endif /* CONFIG_SOC_AU1550 */
121 #ifdef CONFIG_SOC_AU1200
122 { DSCR_CMD0_UART0_TX, DEV_FLAGS_OUT, 0, 8, 0x11100004, 0, 0 },
123 { DSCR_CMD0_UART0_RX, DEV_FLAGS_IN, 0, 8, 0x11100000, 0, 0 },
124 { DSCR_CMD0_UART1_TX, DEV_FLAGS_OUT, 0, 8, 0x11200004, 0, 0 },
125 { DSCR_CMD0_UART1_RX, DEV_FLAGS_IN, 0, 8, 0x11200000, 0, 0 },
127 { DSCR_CMD0_DMA_REQ0, 0, 0, 0, 0x00000000, 0, 0 },
128 { DSCR_CMD0_DMA_REQ1, 0, 0, 0, 0x00000000, 0, 0 },
130 { DSCR_CMD0_MAE_BE, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
131 { DSCR_CMD0_MAE_FE, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
132 { DSCR_CMD0_MAE_BOTH, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
133 { DSCR_CMD0_LCD, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
135 { DSCR_CMD0_SDMS_TX0, DEV_FLAGS_OUT, 4, 8, 0x10600000, 0, 0 },
136 { DSCR_CMD0_SDMS_RX0, DEV_FLAGS_IN, 4, 8, 0x10600004, 0, 0 },
137 { DSCR_CMD0_SDMS_TX1, DEV_FLAGS_OUT, 4, 8, 0x10680000, 0, 0 },
138 { DSCR_CMD0_SDMS_RX1, DEV_FLAGS_IN, 4, 8, 0x10680004, 0, 0 },
140 { DSCR_CMD0_AES_RX, DEV_FLAGS_IN , 4, 32, 0x10300008, 0, 0 },
141 { DSCR_CMD0_AES_TX, DEV_FLAGS_OUT, 4, 32, 0x10300004, 0, 0 },
143 { DSCR_CMD0_PSC0_TX, DEV_FLAGS_OUT, 0, 16, 0x11a0001c, 0, 0 },
144 { DSCR_CMD0_PSC0_RX, DEV_FLAGS_IN, 0, 16, 0x11a0001c, 0, 0 },
145 { DSCR_CMD0_PSC0_SYNC, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
147 { DSCR_CMD0_PSC1_TX, DEV_FLAGS_OUT, 0, 16, 0x11b0001c, 0, 0 },
148 { DSCR_CMD0_PSC1_RX, DEV_FLAGS_IN, 0, 16, 0x11b0001c, 0, 0 },
149 { DSCR_CMD0_PSC1_SYNC, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
151 { DSCR_CMD0_CIM_RXA, DEV_FLAGS_IN, 0, 32, 0x14004020, 0, 0 },
152 { DSCR_CMD0_CIM_RXB, DEV_FLAGS_IN, 0, 32, 0x14004040, 0, 0 },
153 { DSCR_CMD0_CIM_RXC, DEV_FLAGS_IN, 0, 32, 0x14004060, 0, 0 },
154 { DSCR_CMD0_CIM_SYNC, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
156 { DSCR_CMD0_NAND_FLASH, DEV_FLAGS_IN, 0, 0, 0x00000000, 0, 0 },
158 #endif // CONFIG_SOC_AU1200
160 { DSCR_CMD0_THROTTLE, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
161 { DSCR_CMD0_ALWAYS, DEV_FLAGS_ANYUSE, 0, 0, 0x00000000, 0, 0 },
163 /* Provide 16 user definable device types */
164 { ~0, 0, 0, 0, 0, 0, 0 },
165 { ~0, 0, 0, 0, 0, 0, 0 },
166 { ~0, 0, 0, 0, 0, 0, 0 },
167 { ~0, 0, 0, 0, 0, 0, 0 },
168 { ~0, 0, 0, 0, 0, 0, 0 },
169 { ~0, 0, 0, 0, 0, 0, 0 },
170 { ~0, 0, 0, 0, 0, 0, 0 },
171 { ~0, 0, 0, 0, 0, 0, 0 },
172 { ~0, 0, 0, 0, 0, 0, 0 },
173 { ~0, 0, 0, 0, 0, 0, 0 },
174 { ~0, 0, 0, 0, 0, 0, 0 },
175 { ~0, 0, 0, 0, 0, 0, 0 },
176 { ~0, 0, 0, 0, 0, 0, 0 },
177 { ~0, 0, 0, 0, 0, 0, 0 },
178 { ~0, 0, 0, 0, 0, 0, 0 },
179 { ~0, 0, 0, 0, 0, 0, 0 },
182 #define DBDEV_TAB_SIZE ARRAY_SIZE(dbdev_tab)
184 static chan_tab_t *chan_tab_ptr[NUM_DBDMA_CHANS];
187 find_dbdev_id(u32 id)
191 for (i = 0; i < DBDEV_TAB_SIZE; ++i) {
199 void * au1xxx_ddma_get_nextptr_virt(au1x_ddma_desc_t *dp)
201 return phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
203 EXPORT_SYMBOL(au1xxx_ddma_get_nextptr_virt);
206 au1xxx_ddma_add_device(dbdev_tab_t *dev)
210 static u16 new_id=0x1000;
212 p = find_dbdev_id(~0);
215 memcpy(p, dev, sizeof(dbdev_tab_t));
216 p->dev_id = DSCR_DEV2CUSTOM_ID(new_id, dev->dev_id);
220 printk("add_device: id:%x flags:%x padd:%x\n",
221 p->dev_id, p->dev_flags, p->dev_physaddr );
227 EXPORT_SYMBOL(au1xxx_ddma_add_device);
229 /* Allocate a channel and return a non-zero descriptor if successful.
232 au1xxx_dbdma_chan_alloc(u32 srcid, u32 destid,
233 void (*callback)(int, void *), void *callparam)
239 dbdev_tab_t *stp, *dtp;
243 /* We do the intialization on the first channel allocation.
244 * We have to wait because of the interrupt handler initialization
245 * which can't be done successfully during board set up.
247 if (!dbdma_initialized)
249 dbdma_initialized = 1;
251 if ((stp = find_dbdev_id(srcid)) == NULL)
253 if ((dtp = find_dbdev_id(destid)) == NULL)
259 /* Check to see if we can get both channels.
261 spin_lock_irqsave(&au1xxx_dbdma_spin_lock, flags);
262 if (!(stp->dev_flags & DEV_FLAGS_INUSE) ||
263 (stp->dev_flags & DEV_FLAGS_ANYUSE)) {
265 stp->dev_flags |= DEV_FLAGS_INUSE;
266 if (!(dtp->dev_flags & DEV_FLAGS_INUSE) ||
267 (dtp->dev_flags & DEV_FLAGS_ANYUSE)) {
268 /* Got destination */
269 dtp->dev_flags |= DEV_FLAGS_INUSE;
272 /* Can't get dest. Release src.
274 stp->dev_flags &= ~DEV_FLAGS_INUSE;
281 spin_unlock_irqrestore(&au1xxx_dbdma_spin_lock, flags);
284 /* Let's see if we can allocate a channel for it.
288 spin_lock_irqsave(&au1xxx_dbdma_spin_lock, flags);
289 for (i=0; i<NUM_DBDMA_CHANS; i++) {
290 if (chan_tab_ptr[i] == NULL) {
291 /* If kmalloc fails, it is caught below same
292 * as a channel not available.
294 ctp = kmalloc(sizeof(chan_tab_t), GFP_ATOMIC);
295 chan_tab_ptr[i] = ctp;
299 spin_unlock_irqrestore(&au1xxx_dbdma_spin_lock, flags);
302 memset(ctp, 0, sizeof(chan_tab_t));
303 ctp->chan_index = chan = i;
304 dcp = DDMA_CHANNEL_BASE;
305 dcp += (0x0100 * chan);
306 ctp->chan_ptr = (au1x_dma_chan_t *)dcp;
307 cp = (au1x_dma_chan_t *)dcp;
309 ctp->chan_dest = dtp;
310 ctp->chan_callback = callback;
311 ctp->chan_callparam = callparam;
313 /* Initialize channel configuration.
316 if (stp->dev_intlevel)
318 if (stp->dev_intpolarity)
320 if (dtp->dev_intlevel)
322 if (dtp->dev_intpolarity)
324 if ((stp->dev_flags & DEV_FLAGS_SYNC) ||
325 (dtp->dev_flags & DEV_FLAGS_SYNC))
330 /* Return a non-zero value that can be used to
331 * find the channel information in subsequent
334 rv = (u32)(&chan_tab_ptr[chan]);
337 /* Release devices */
338 stp->dev_flags &= ~DEV_FLAGS_INUSE;
339 dtp->dev_flags &= ~DEV_FLAGS_INUSE;
344 EXPORT_SYMBOL(au1xxx_dbdma_chan_alloc);
346 /* Set the device width if source or destination is a FIFO.
347 * Should be 8, 16, or 32 bits.
350 au1xxx_dbdma_set_devwidth(u32 chanid, int bits)
354 dbdev_tab_t *stp, *dtp;
356 ctp = *((chan_tab_t **)chanid);
358 dtp = ctp->chan_dest;
361 if (stp->dev_flags & DEV_FLAGS_IN) { /* Source in fifo */
362 rv = stp->dev_devwidth;
363 stp->dev_devwidth = bits;
365 if (dtp->dev_flags & DEV_FLAGS_OUT) { /* Destination out fifo */
366 rv = dtp->dev_devwidth;
367 dtp->dev_devwidth = bits;
372 EXPORT_SYMBOL(au1xxx_dbdma_set_devwidth);
374 /* Allocate a descriptor ring, initializing as much as possible.
377 au1xxx_dbdma_ring_alloc(u32 chanid, int entries)
380 u32 desc_base, srcid, destid;
381 u32 cmd0, cmd1, src1, dest1;
384 dbdev_tab_t *stp, *dtp;
385 au1x_ddma_desc_t *dp;
387 /* I guess we could check this to be within the
388 * range of the table......
390 ctp = *((chan_tab_t **)chanid);
392 dtp = ctp->chan_dest;
394 /* The descriptors must be 32-byte aligned. There is a
395 * possibility the allocation will give us such an address,
396 * and if we try that first we are likely to not waste larger
399 desc_base = (u32)kmalloc(entries * sizeof(au1x_ddma_desc_t),
404 if (desc_base & 0x1f) {
405 /* Lost....do it again, allocate extra, and round
408 kfree((const void *)desc_base);
409 i = entries * sizeof(au1x_ddma_desc_t);
410 i += (sizeof(au1x_ddma_desc_t) - 1);
411 if ((desc_base = (u32)kmalloc(i, GFP_KERNEL|GFP_DMA)) == 0)
414 desc_base = ALIGN_ADDR(desc_base, sizeof(au1x_ddma_desc_t));
416 dp = (au1x_ddma_desc_t *)desc_base;
418 /* Keep track of the base descriptor.
420 ctp->chan_desc_base = dp;
422 /* Initialize the rings with as much information as we know.
425 destid = dtp->dev_id;
427 cmd0 = cmd1 = src1 = dest1 = 0;
430 cmd0 |= DSCR_CMD0_SID(srcid);
431 cmd0 |= DSCR_CMD0_DID(destid);
432 cmd0 |= DSCR_CMD0_IE | DSCR_CMD0_CV;
433 cmd0 |= DSCR_CMD0_ST(DSCR_CMD0_ST_NOCHANGE);
435 /* is it mem to mem transfer? */
436 if(((DSCR_CUSTOM2DEV_ID(srcid) == DSCR_CMD0_THROTTLE) || (DSCR_CUSTOM2DEV_ID(srcid) == DSCR_CMD0_ALWAYS)) &&
437 ((DSCR_CUSTOM2DEV_ID(destid) == DSCR_CMD0_THROTTLE) || (DSCR_CUSTOM2DEV_ID(destid) == DSCR_CMD0_ALWAYS))) {
438 cmd0 |= DSCR_CMD0_MEM;
441 switch (stp->dev_devwidth) {
443 cmd0 |= DSCR_CMD0_SW(DSCR_CMD0_BYTE);
446 cmd0 |= DSCR_CMD0_SW(DSCR_CMD0_HALFWORD);
450 cmd0 |= DSCR_CMD0_SW(DSCR_CMD0_WORD);
454 switch (dtp->dev_devwidth) {
456 cmd0 |= DSCR_CMD0_DW(DSCR_CMD0_BYTE);
459 cmd0 |= DSCR_CMD0_DW(DSCR_CMD0_HALFWORD);
463 cmd0 |= DSCR_CMD0_DW(DSCR_CMD0_WORD);
467 /* If the device is marked as an in/out FIFO, ensure it is
470 if (stp->dev_flags & DEV_FLAGS_IN)
471 cmd0 |= DSCR_CMD0_SN; /* Source in fifo */
472 if (dtp->dev_flags & DEV_FLAGS_OUT)
473 cmd0 |= DSCR_CMD0_DN; /* Destination out fifo */
475 /* Set up source1. For now, assume no stride and increment.
476 * A channel attribute update can change this later.
478 switch (stp->dev_tsize) {
480 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE1);
483 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE2);
486 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE4);
490 src1 |= DSCR_SRC1_STS(DSCR_xTS_SIZE8);
494 /* If source input is fifo, set static address.
496 if (stp->dev_flags & DEV_FLAGS_IN) {
497 if ( stp->dev_flags & DEV_FLAGS_BURSTABLE )
498 src1 |= DSCR_SRC1_SAM(DSCR_xAM_BURST);
500 src1 |= DSCR_SRC1_SAM(DSCR_xAM_STATIC);
503 if (stp->dev_physaddr)
504 src0 = stp->dev_physaddr;
506 /* Set up dest1. For now, assume no stride and increment.
507 * A channel attribute update can change this later.
509 switch (dtp->dev_tsize) {
511 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE1);
514 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE2);
517 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE4);
521 dest1 |= DSCR_DEST1_DTS(DSCR_xTS_SIZE8);
525 /* If destination output is fifo, set static address.
527 if (dtp->dev_flags & DEV_FLAGS_OUT) {
528 if ( dtp->dev_flags & DEV_FLAGS_BURSTABLE )
529 dest1 |= DSCR_DEST1_DAM(DSCR_xAM_BURST);
531 dest1 |= DSCR_DEST1_DAM(DSCR_xAM_STATIC);
533 if (dtp->dev_physaddr)
534 dest0 = dtp->dev_physaddr;
537 printk("did:%x sid:%x cmd0:%x cmd1:%x source0:%x source1:%x dest0:%x dest1:%x\n",
538 dtp->dev_id, stp->dev_id, cmd0, cmd1, src0, src1, dest0, dest1 );
540 for (i=0; i<entries; i++) {
541 dp->dscr_cmd0 = cmd0;
542 dp->dscr_cmd1 = cmd1;
543 dp->dscr_source0 = src0;
544 dp->dscr_source1 = src1;
545 dp->dscr_dest0 = dest0;
546 dp->dscr_dest1 = dest1;
550 dp->dscr_nxtptr = DSCR_NXTPTR(virt_to_phys(dp + 1));
554 /* Make last descrptor point to the first.
557 dp->dscr_nxtptr = DSCR_NXTPTR(virt_to_phys(ctp->chan_desc_base));
558 ctp->get_ptr = ctp->put_ptr = ctp->cur_ptr = ctp->chan_desc_base;
560 return (u32)(ctp->chan_desc_base);
562 EXPORT_SYMBOL(au1xxx_dbdma_ring_alloc);
564 /* Put a source buffer into the DMA ring.
565 * This updates the source pointer and byte count. Normally used
566 * for memory to fifo transfers.
569 _au1xxx_dbdma_put_source(u32 chanid, void *buf, int nbytes, u32 flags)
572 au1x_ddma_desc_t *dp;
574 /* I guess we could check this to be within the
575 * range of the table......
577 ctp = *((chan_tab_t **)chanid);
579 /* We should have multiple callers for a particular channel,
580 * an interrupt doesn't affect this pointer nor the descriptor,
581 * so no locking should be needed.
585 /* If the descriptor is valid, we are way ahead of the DMA
586 * engine, so just return an error condition.
588 if (dp->dscr_cmd0 & DSCR_CMD0_V) {
592 /* Load up buffer address and byte count.
594 dp->dscr_source0 = virt_to_phys(buf);
595 dp->dscr_cmd1 = nbytes;
597 if (flags & DDMA_FLAGS_IE)
598 dp->dscr_cmd0 |= DSCR_CMD0_IE;
599 if (flags & DDMA_FLAGS_NOIE)
600 dp->dscr_cmd0 &= ~DSCR_CMD0_IE;
603 * There is an errata on the Au1200/Au1550 parts that could result
604 * in "stale" data being DMA'd. It has to do with the snoop logic on
605 * the dache eviction buffer. NONCOHERENT_IO is on by default for
606 * these parts. If it is fixedin the future, these dma_cache_inv will
607 * just be nothing more than empty macros. See io.h.
609 dma_cache_wback_inv((unsigned long)buf, nbytes);
610 dp->dscr_cmd0 |= DSCR_CMD0_V; /* Let it rip */
612 dma_cache_wback_inv((unsigned long)dp, sizeof(dp));
613 ctp->chan_ptr->ddma_dbell = 0;
615 /* Get next descriptor pointer.
617 ctp->put_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
619 /* return something not zero.
623 EXPORT_SYMBOL(_au1xxx_dbdma_put_source);
625 /* Put a destination buffer into the DMA ring.
626 * This updates the destination pointer and byte count. Normally used
627 * to place an empty buffer into the ring for fifo to memory transfers.
630 _au1xxx_dbdma_put_dest(u32 chanid, void *buf, int nbytes, u32 flags)
633 au1x_ddma_desc_t *dp;
635 /* I guess we could check this to be within the
636 * range of the table......
638 ctp = *((chan_tab_t **)chanid);
640 /* We should have multiple callers for a particular channel,
641 * an interrupt doesn't affect this pointer nor the descriptor,
642 * so no locking should be needed.
646 /* If the descriptor is valid, we are way ahead of the DMA
647 * engine, so just return an error condition.
649 if (dp->dscr_cmd0 & DSCR_CMD0_V)
652 /* Load up buffer address and byte count */
655 if (flags & DDMA_FLAGS_IE)
656 dp->dscr_cmd0 |= DSCR_CMD0_IE;
657 if (flags & DDMA_FLAGS_NOIE)
658 dp->dscr_cmd0 &= ~DSCR_CMD0_IE;
660 dp->dscr_dest0 = virt_to_phys(buf);
661 dp->dscr_cmd1 = nbytes;
663 printk("cmd0:%x cmd1:%x source0:%x source1:%x dest0:%x dest1:%x\n",
664 dp->dscr_cmd0, dp->dscr_cmd1, dp->dscr_source0,
665 dp->dscr_source1, dp->dscr_dest0, dp->dscr_dest1 );
668 * There is an errata on the Au1200/Au1550 parts that could result in
669 * "stale" data being DMA'd. It has to do with the snoop logic on the
670 * dache eviction buffer. NONCOHERENT_IO is on by default for these
671 * parts. If it is fixedin the future, these dma_cache_inv will just
672 * be nothing more than empty macros. See io.h.
674 dma_cache_inv((unsigned long)buf, nbytes);
675 dp->dscr_cmd0 |= DSCR_CMD0_V; /* Let it rip */
677 dma_cache_wback_inv((unsigned long)dp, sizeof(dp));
678 ctp->chan_ptr->ddma_dbell = 0;
680 /* Get next descriptor pointer.
682 ctp->put_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
684 /* return something not zero.
688 EXPORT_SYMBOL(_au1xxx_dbdma_put_dest);
690 /* Get a destination buffer into the DMA ring.
691 * Normally used to get a full buffer from the ring during fifo
692 * to memory transfers. This does not set the valid bit, you will
693 * have to put another destination buffer to keep the DMA going.
696 au1xxx_dbdma_get_dest(u32 chanid, void **buf, int *nbytes)
699 au1x_ddma_desc_t *dp;
702 /* I guess we could check this to be within the
703 * range of the table......
705 ctp = *((chan_tab_t **)chanid);
707 /* We should have multiple callers for a particular channel,
708 * an interrupt doesn't affect this pointer nor the descriptor,
709 * so no locking should be needed.
713 /* If the descriptor is valid, we are way ahead of the DMA
714 * engine, so just return an error condition.
716 if (dp->dscr_cmd0 & DSCR_CMD0_V)
719 /* Return buffer address and byte count.
721 *buf = (void *)(phys_to_virt(dp->dscr_dest0));
722 *nbytes = dp->dscr_cmd1;
725 /* Get next descriptor pointer.
727 ctp->get_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
729 /* return something not zero.
734 EXPORT_SYMBOL_GPL(au1xxx_dbdma_get_dest);
737 au1xxx_dbdma_stop(u32 chanid)
741 int halt_timeout = 0;
743 ctp = *((chan_tab_t **)chanid);
746 cp->ddma_cfg &= ~DDMA_CFG_EN; /* Disable channel */
748 while (!(cp->ddma_stat & DDMA_STAT_H)) {
751 if (halt_timeout > 100) {
752 printk("warning: DMA channel won't halt\n");
756 /* clear current desc valid and doorbell */
757 cp->ddma_stat |= (DDMA_STAT_DB | DDMA_STAT_V);
760 EXPORT_SYMBOL(au1xxx_dbdma_stop);
762 /* Start using the current descriptor pointer. If the dbdma encounters
763 * a not valid descriptor, it will stop. In this case, we can just
764 * continue by adding a buffer to the list and starting again.
767 au1xxx_dbdma_start(u32 chanid)
772 ctp = *((chan_tab_t **)chanid);
774 cp->ddma_desptr = virt_to_phys(ctp->cur_ptr);
775 cp->ddma_cfg |= DDMA_CFG_EN; /* Enable channel */
780 EXPORT_SYMBOL(au1xxx_dbdma_start);
783 au1xxx_dbdma_reset(u32 chanid)
786 au1x_ddma_desc_t *dp;
788 au1xxx_dbdma_stop(chanid);
790 ctp = *((chan_tab_t **)chanid);
791 ctp->get_ptr = ctp->put_ptr = ctp->cur_ptr = ctp->chan_desc_base;
793 /* Run through the descriptors and reset the valid indicator.
795 dp = ctp->chan_desc_base;
798 dp->dscr_cmd0 &= ~DSCR_CMD0_V;
799 /* reset our SW status -- this is used to determine
800 * if a descriptor is in use by upper level SW. Since
801 * posting can reset 'V' bit.
804 dp = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
805 } while (dp != ctp->chan_desc_base);
807 EXPORT_SYMBOL(au1xxx_dbdma_reset);
810 au1xxx_get_dma_residue(u32 chanid)
816 ctp = *((chan_tab_t **)chanid);
819 /* This is only valid if the channel is stopped.
821 rv = cp->ddma_bytecnt;
827 EXPORT_SYMBOL_GPL(au1xxx_get_dma_residue);
830 au1xxx_dbdma_chan_free(u32 chanid)
833 dbdev_tab_t *stp, *dtp;
835 ctp = *((chan_tab_t **)chanid);
837 dtp = ctp->chan_dest;
839 au1xxx_dbdma_stop(chanid);
841 kfree((void *)ctp->chan_desc_base);
843 stp->dev_flags &= ~DEV_FLAGS_INUSE;
844 dtp->dev_flags &= ~DEV_FLAGS_INUSE;
845 chan_tab_ptr[ctp->chan_index] = NULL;
849 EXPORT_SYMBOL(au1xxx_dbdma_chan_free);
852 dbdma_interrupt(int irq, void *dev_id)
857 au1x_ddma_desc_t *dp;
860 intstat = dbdma_gptr->ddma_intstat;
862 chan_index = __ffs(intstat);
864 ctp = chan_tab_ptr[chan_index];
873 if (ctp->chan_callback)
874 (ctp->chan_callback)(irq, ctp->chan_callparam);
876 ctp->cur_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
877 return IRQ_RETVAL(1);
880 static void au1xxx_dbdma_init(void)
884 dbdma_gptr->ddma_config = 0;
885 dbdma_gptr->ddma_throttle = 0;
886 dbdma_gptr->ddma_inten = 0xffff;
889 #if defined(CONFIG_SOC_AU1550)
890 irq_nr = AU1550_DDMA_INT;
891 #elif defined(CONFIG_SOC_AU1200)
892 irq_nr = AU1200_DDMA_INT;
894 #error Unknown Au1x00 SOC
897 if (request_irq(irq_nr, dbdma_interrupt, IRQF_DISABLED,
898 "Au1xxx dbdma", (void *)dbdma_gptr))
899 printk("Can't get 1550 dbdma irq");
903 au1xxx_dbdma_dump(u32 chanid)
906 au1x_ddma_desc_t *dp;
907 dbdev_tab_t *stp, *dtp;
911 ctp = *((chan_tab_t **)chanid);
913 dtp = ctp->chan_dest;
916 printk("Chan %x, stp %x (dev %d) dtp %x (dev %d) \n",
917 (u32)ctp, (u32)stp, stp - dbdev_tab, (u32)dtp, dtp - dbdev_tab);
918 printk("desc base %x, get %x, put %x, cur %x\n",
919 (u32)(ctp->chan_desc_base), (u32)(ctp->get_ptr),
920 (u32)(ctp->put_ptr), (u32)(ctp->cur_ptr));
922 printk("dbdma chan %x\n", (u32)cp);
923 printk("cfg %08x, desptr %08x, statptr %08x\n",
924 cp->ddma_cfg, cp->ddma_desptr, cp->ddma_statptr);
925 printk("dbell %08x, irq %08x, stat %08x, bytecnt %08x\n",
926 cp->ddma_dbell, cp->ddma_irq, cp->ddma_stat, cp->ddma_bytecnt);
929 /* Run through the descriptors
931 dp = ctp->chan_desc_base;
934 printk("Dp[%d]= %08x, cmd0 %08x, cmd1 %08x\n",
935 i++, (u32)dp, dp->dscr_cmd0, dp->dscr_cmd1);
936 printk("src0 %08x, src1 %08x, dest0 %08x, dest1 %08x\n",
937 dp->dscr_source0, dp->dscr_source1, dp->dscr_dest0, dp->dscr_dest1);
938 printk("stat %08x, nxtptr %08x\n",
939 dp->dscr_stat, dp->dscr_nxtptr);
940 dp = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
941 } while (dp != ctp->chan_desc_base);
944 /* Put a descriptor into the DMA ring.
945 * This updates the source/destination pointers and byte count.
948 au1xxx_dbdma_put_dscr(u32 chanid, au1x_ddma_desc_t *dscr )
951 au1x_ddma_desc_t *dp;
954 /* I guess we could check this to be within the
955 * range of the table......
957 ctp = *((chan_tab_t **)chanid);
959 /* We should have multiple callers for a particular channel,
960 * an interrupt doesn't affect this pointer nor the descriptor,
961 * so no locking should be needed.
965 /* If the descriptor is valid, we are way ahead of the DMA
966 * engine, so just return an error condition.
968 if (dp->dscr_cmd0 & DSCR_CMD0_V)
971 /* Load up buffer addresses and byte count.
973 dp->dscr_dest0 = dscr->dscr_dest0;
974 dp->dscr_source0 = dscr->dscr_source0;
975 dp->dscr_dest1 = dscr->dscr_dest1;
976 dp->dscr_source1 = dscr->dscr_source1;
977 dp->dscr_cmd1 = dscr->dscr_cmd1;
978 nbytes = dscr->dscr_cmd1;
979 /* Allow the caller to specifiy if an interrupt is generated */
980 dp->dscr_cmd0 &= ~DSCR_CMD0_IE;
981 dp->dscr_cmd0 |= dscr->dscr_cmd0 | DSCR_CMD0_V;
982 ctp->chan_ptr->ddma_dbell = 0;
984 /* Get next descriptor pointer.
986 ctp->put_ptr = phys_to_virt(DSCR_GET_NXTPTR(dp->dscr_nxtptr));
988 /* return something not zero.
993 #endif /* defined(CONFIG_SOC_AU1550) || defined(CONFIG_SOC_AU1200) */