sh: Add maple bus support for the SEGA Dreamcast.
[linux-2.6.git] / drivers / sh / maple / maple.c
1 /*
2  * Core maple bus functionality
3  *
4  *  Copyright (C) 2007 Adrian McMenamin
5  *
6  * Based on 2.4 code by:
7  *
8  *  Copyright (C) 2000-2001 YAEGASHI Takeshi
9  *  Copyright (C) 2001 M. R. Brown
10  *  Copyright (C) 2001 Paul Mundt
11  *
12  * and others.
13  *
14  * This file is subject to the terms and conditions of the GNU General Public
15  * License.  See the file "COPYING" in the main directory of this archive
16  * for more details.
17  */
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/device.h>
21 #include <linux/module.h>
22 #include <linux/interrupt.h>
23 #include <linux/list.h>
24 #include <linux/io.h>
25 #include <linux/slab.h>
26 #include <linux/maple.h>
27 #include <linux/dma-mapping.h>
28 #include <asm/cacheflush.h>
29 #include <asm/dma.h>
30 #include <asm/io.h>
31 #include <asm/mach/dma.h>
32 #include <asm/mach/sysasic.h>
33 #include <asm/mach/maple.h>
34
35 MODULE_AUTHOR("Yaegshi Takeshi, Paul Mundt, M.R. Brown, Adrian McMenamin");
36 MODULE_DESCRIPTION("Maple bus driver for Dreamcast");
37 MODULE_LICENSE("GPL v2");
38 MODULE_SUPPORTED_DEVICE("{{SEGA, Dreamcast/Maple}}");
39
40 static void maple_dma_handler(struct work_struct *work);
41 static void maple_vblank_handler(struct work_struct *work);
42
43 static DECLARE_WORK(maple_dma_process, maple_dma_handler);
44 static DECLARE_WORK(maple_vblank_process, maple_vblank_handler);
45
46 static LIST_HEAD(maple_waitq);
47 static LIST_HEAD(maple_sentq);
48
49 static DEFINE_MUTEX(maple_list_lock);
50
51 static struct maple_driver maple_dummy_driver;
52 static struct device maple_bus;
53 static int subdevice_map[MAPLE_PORTS];
54 static unsigned long *maple_sendbuf, *maple_sendptr, *maple_lastptr;
55 static unsigned long maple_pnp_time;
56 static int started, scanning, liststatus;
57 static struct kmem_cache *maple_queue_cache;
58
59 struct maple_device_specify {
60        int port;
61        int unit;
62 };
63
64 /**
65  *  maple_driver_register - register a device driver
66  *  automatically makes the driver bus a maple bus
67  *  @drv: the driver to be registered
68  */
69 int maple_driver_register(struct device_driver *drv)
70 {
71        if (!drv)
72                return -EINVAL;
73        drv->bus = &maple_bus_type;
74        return driver_register(drv);
75 }
76 EXPORT_SYMBOL_GPL(maple_driver_register);
77
78 /* set hardware registers to enable next round of dma */
79 static void maplebus_dma_reset(void)
80 {
81        ctrl_outl(MAPLE_MAGIC, MAPLE_RESET);
82        /* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */
83        ctrl_outl(1, MAPLE_TRIGTYPE);
84        ctrl_outl(MAPLE_2MBPS | MAPLE_TIMEOUT(50000), MAPLE_SPEED);
85        ctrl_outl(PHYSADDR(maple_sendbuf), MAPLE_DMAADDR);
86        ctrl_outl(1, MAPLE_ENABLE);
87 }
88
89 /**
90  * maple_getcond_callback - setup handling MAPLE_COMMAND_GETCOND
91  * @dev: device responding
92  * @callback: handler callback
93  * @interval: interval in jiffies between callbacks
94  * @function: the function code for the device
95  */
96 void maple_getcond_callback(struct maple_device *dev,
97                            void (*callback) (struct mapleq * mq),
98                            unsigned long interval, unsigned long function)
99 {
100        dev->callback = callback;
101        dev->interval = interval;
102        dev->function = cpu_to_be32(function);
103        dev->when = jiffies;
104 }
105 EXPORT_SYMBOL_GPL(maple_getcond_callback);
106
107 static int maple_dma_done(void)
108 {
109        return (ctrl_inl(MAPLE_STATE) & 1) == 0;
110 }
111
112 static void maple_release_device(struct device *dev)
113 {
114        if (dev->type) {
115                kfree(dev->type->name);
116                kfree(dev->type);
117        }
118 }
119
120 /**
121  * maple_add_packet - add a single instruction to the queue
122  * @mq: instruction to add to waiting queue
123  */
124 void maple_add_packet(struct mapleq *mq)
125 {
126        mutex_lock(&maple_list_lock);
127        list_add(&mq->list, &maple_waitq);
128        mutex_unlock(&maple_list_lock);
129 }
130 EXPORT_SYMBOL_GPL(maple_add_packet);
131
132 static struct mapleq *maple_allocq(struct maple_device *dev)
133 {
134        struct mapleq *mq;
135
136        mq = kmalloc(sizeof(*mq), GFP_KERNEL);
137        if (!mq)
138                return NULL;
139
140        mq->dev = dev;
141        mq->recvbufdcsp = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
142        mq->recvbuf = (void *) P2SEGADDR(mq->recvbufdcsp);
143        if (!mq->recvbuf) {
144                kfree(mq);
145                return NULL;
146        }
147
148        return mq;
149 }
150
151 static struct maple_device *maple_alloc_dev(int port, int unit)
152 {
153        struct maple_device *dev;
154
155        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
156        if (!dev)
157                return NULL;
158
159        dev->port = port;
160        dev->unit = unit;
161        dev->mq = maple_allocq(dev);
162
163        if (!dev->mq) {
164                kfree(dev);
165                return NULL;
166        }
167
168        return dev;
169 }
170
171 static void maple_free_dev(struct maple_device *mdev)
172 {
173        if (!mdev)
174                return;
175        if (mdev->mq) {
176                kmem_cache_free(maple_queue_cache, mdev->mq->recvbufdcsp);
177                kfree(mdev->mq);
178        }
179        kfree(mdev);
180 }
181
182 /* process the command queue into a maple command block
183  * terminating command has bit 32 of first long set to 0
184  */
185 static void maple_build_block(struct mapleq *mq)
186 {
187        int port, unit, from, to, len;
188        unsigned long *lsendbuf = mq->sendbuf;
189
190        port = mq->dev->port & 3;
191        unit = mq->dev->unit;
192        len = mq->length;
193        from = port << 6;
194        to = (port << 6) | (unit > 0 ? (1 << (unit - 1)) & 0x1f : 0x20);
195
196        *maple_lastptr &= 0x7fffffff;
197        maple_lastptr = maple_sendptr;
198
199        *maple_sendptr++ = (port << 16) | len | 0x80000000;
200        *maple_sendptr++ = PHYSADDR(mq->recvbuf);
201        *maple_sendptr++ =
202            mq->command | (to << 8) | (from << 16) | (len << 24);
203
204        while (len-- > 0)
205                *maple_sendptr++ = *lsendbuf++;
206 }
207
208 /* build up command queue */
209 static void maple_send(void)
210 {
211        int i;
212        int maple_packets;
213        struct mapleq *mq, *nmq;
214
215        if (!list_empty(&maple_sentq))
216                return;
217        if (list_empty(&maple_waitq) || !maple_dma_done())
218                return;
219        maple_packets = 0;
220        maple_sendptr = maple_lastptr = maple_sendbuf;
221        list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
222                maple_build_block(mq);
223                list_move(&mq->list, &maple_sentq);
224                if (maple_packets++ > MAPLE_MAXPACKETS)
225                        break;
226        }
227        if (maple_packets > 0) {
228                for (i = 0; i < (1 << MAPLE_DMA_PAGES); i++)
229                        dma_cache_sync(0, maple_sendbuf + i * PAGE_SIZE,
230                                       PAGE_SIZE, DMA_BIDIRECTIONAL);
231        }
232 }
233
234 static int attach_matching_maple_driver(struct device_driver *driver,
235                                        void *devptr)
236 {
237        struct maple_driver *maple_drv;
238        struct maple_device *mdev;
239
240        mdev = devptr;
241        maple_drv = to_maple_driver(driver);
242        if (mdev->devinfo.function & be32_to_cpu(maple_drv->function)) {
243                if (maple_drv->connect(mdev) == 0) {
244                        mdev->driver = maple_drv;
245                        return 1;
246                }
247        }
248        return 0;
249 }
250
251 static void maple_detach_driver(struct maple_device *mdev)
252 {
253        if (!mdev)
254                return;
255        if (mdev->driver) {
256                if (mdev->driver->disconnect)
257                        mdev->driver->disconnect(mdev);
258        }
259        mdev->driver = NULL;
260        if (mdev->registered) {
261                maple_release_device(&mdev->dev);
262                device_unregister(&mdev->dev);
263        }
264        mdev->registered = 0;
265        maple_free_dev(mdev);
266 }
267
268 /* process initial MAPLE_COMMAND_DEVINFO for each device or port */
269 static void maple_attach_driver(struct maple_device *dev)
270 {
271        char *p;
272
273        char *recvbuf;
274        unsigned long function;
275        int matched, retval;
276
277        recvbuf = dev->mq->recvbuf;
278        memcpy(&dev->devinfo, recvbuf + 4, sizeof(dev->devinfo));
279        memcpy(dev->product_name, dev->devinfo.product_name, 30);
280        memcpy(dev->product_licence, dev->devinfo.product_licence, 60);
281        dev->product_name[30] = '\0';
282        dev->product_licence[60] = '\0';
283
284        for (p = dev->product_name + 29; dev->product_name <= p; p--)
285                if (*p == ' ')
286                        *p = '\0';
287                else
288                        break;
289
290        for (p = dev->product_licence + 59; dev->product_licence <= p; p--)
291                if (*p == ' ')
292                        *p = '\0';
293                else
294                        break;
295
296        function = be32_to_cpu(dev->devinfo.function);
297
298        if (function > 0x200) {
299                /* Do this silently - as not a real device */
300                function = 0;
301                dev->driver = &maple_dummy_driver;
302                sprintf(dev->dev.bus_id, "%d:0.port", dev->port);
303        } else {
304                printk(KERN_INFO
305                       "Maple bus at (%d, %d): Connected function 0x%lX\n",
306                       dev->port, dev->unit, function);
307
308                matched =
309                    bus_for_each_drv(&maple_bus_type, NULL, dev,
310                                     attach_matching_maple_driver);
311
312                if (matched == 0) {
313                        /* Driver does not exist yet */
314                        printk(KERN_INFO
315                               "No maple driver found for this device\n");
316                        dev->driver = &maple_dummy_driver;
317                }
318
319                sprintf(dev->dev.bus_id, "%d:0%d.%lX", dev->port,
320                        dev->unit, function);
321        }
322        dev->function = function;
323        dev->dev.bus = &maple_bus_type;
324        dev->dev.parent = &maple_bus;
325        dev->dev.release = &maple_release_device;
326        retval = device_register(&dev->dev);
327        if (retval) {
328                printk(KERN_INFO
329                       "Maple bus: Attempt to register device (%x, %x) failed.\n",
330                       dev->port, dev->unit);
331                maple_free_dev(dev);
332        }
333        dev->registered = 1;
334 }
335
336 /*
337  * if device has been registered for the given
338  * port and unit then return 1 - allows identification
339  * of which devices need to be attached or detached
340  */
341 static int detach_maple_device(struct device *device, void *portptr)
342 {
343        struct maple_device_specify *ds;
344        struct maple_device *mdev;
345
346        ds = portptr;
347        mdev = to_maple_dev(device);
348        if (mdev->port == ds->port && mdev->unit == ds->unit)
349                return 1;
350        return 0;
351 }
352
353 static int setup_maple_commands(struct device *device, void *ignored)
354 {
355        struct maple_device *maple_dev = to_maple_dev(device);
356
357        if ((maple_dev->interval > 0)
358            && time_after(jiffies, maple_dev->when)) {
359                maple_dev->when = jiffies + maple_dev->interval;
360                maple_dev->mq->command = MAPLE_COMMAND_GETCOND;
361                maple_dev->mq->sendbuf = &maple_dev->function;
362                maple_dev->mq->length = 1;
363                maple_add_packet(maple_dev->mq);
364                liststatus++;
365        } else {
366                if (time_after(jiffies, maple_pnp_time)) {
367                        maple_dev->mq->command = MAPLE_COMMAND_DEVINFO;
368                        maple_dev->mq->length = 0;
369                        maple_add_packet(maple_dev->mq);
370                        liststatus++;
371                }
372        }
373
374        return 0;
375 }
376
377 /* VBLANK bottom half - implemented via workqueue */
378 static void maple_vblank_handler(struct work_struct *work)
379 {
380        if (!maple_dma_done())
381                return;
382        if (!list_empty(&maple_sentq))
383                return;
384        ctrl_outl(0, MAPLE_ENABLE);
385        liststatus = 0;
386        bus_for_each_dev(&maple_bus_type, NULL, NULL,
387                         setup_maple_commands);
388        if (time_after(jiffies, maple_pnp_time))
389                maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
390        if (liststatus && list_empty(&maple_sentq)) {
391                INIT_LIST_HEAD(&maple_sentq);
392                maple_send();
393        }
394        maplebus_dma_reset();
395 }
396
397 /* handle devices added via hotplugs - placing them on queue for DEVINFO*/
398 static void maple_map_subunits(struct maple_device *mdev, int submask)
399 {
400        int retval, k, devcheck;
401        struct maple_device *mdev_add;
402        struct maple_device_specify ds;
403
404        for (k = 0; k < 5; k++) {
405                ds.port = mdev->port;
406                ds.unit = k + 1;
407                retval =
408                    bus_for_each_dev(&maple_bus_type, NULL, &ds,
409                                     detach_maple_device);
410                if (retval) {
411                        submask = submask >> 1;
412                        continue;
413                }
414                devcheck = submask & 0x01;
415                if (devcheck) {
416                        mdev_add = maple_alloc_dev(mdev->port, k + 1);
417                        if (!mdev_add)
418                                return;
419                        mdev_add->mq->command = MAPLE_COMMAND_DEVINFO;
420                        mdev_add->mq->length = 0;
421                        maple_add_packet(mdev_add->mq);
422                        scanning = 1;
423                }
424                submask = submask >> 1;
425        }
426 }
427
428 /* mark a device as removed */
429 static void maple_clean_submap(struct maple_device *mdev)
430 {
431        int killbit;
432
433        killbit = (mdev->unit > 0 ? (1 << (mdev->unit - 1)) & 0x1f : 0x20);
434        killbit = ~killbit;
435        killbit &= 0xFF;
436        subdevice_map[mdev->port] = subdevice_map[mdev->port] & killbit;
437 }
438
439 /* handle empty port or hotplug removal */
440 static void maple_response_none(struct maple_device *mdev,
441                                struct mapleq *mq)
442 {
443        if (mdev->unit != 0) {
444                list_del(&mq->list);
445                maple_clean_submap(mdev);
446                printk(KERN_INFO
447                       "Maple bus device detaching at (%d, %d)\n",
448                       mdev->port, mdev->unit);
449                maple_detach_driver(mdev);
450                return;
451        }
452        if (!started) {
453                printk(KERN_INFO "No maple devices attached to port %d\n",
454                       mdev->port);
455                return;
456        }
457        maple_clean_submap(mdev);
458 }
459
460 /* preprocess hotplugs or scans */
461 static void maple_response_devinfo(struct maple_device *mdev,
462                                   char *recvbuf)
463 {
464        char submask;
465        if ((!started) || (scanning == 2)) {
466                maple_attach_driver(mdev);
467                return;
468        }
469        if (mdev->unit == 0) {
470                submask = recvbuf[2] & 0x1F;
471                if (submask ^ subdevice_map[mdev->port]) {
472                        maple_map_subunits(mdev, submask);
473                        subdevice_map[mdev->port] = submask;
474                }
475        }
476 }
477
478 /* maple dma end bottom half - implemented via workqueue */
479 static void maple_dma_handler(struct work_struct *work)
480 {
481        struct mapleq *mq, *nmq;
482        struct maple_device *dev;
483        char *recvbuf;
484        enum maple_code code;
485
486        if (!maple_dma_done())
487                return;
488        ctrl_outl(0, MAPLE_ENABLE);
489        if (!list_empty(&maple_sentq)) {
490                list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
491                        recvbuf = mq->recvbuf;
492                        code = recvbuf[0];
493                        dev = mq->dev;
494                        switch (code) {
495                        case MAPLE_RESPONSE_NONE:
496                                maple_response_none(dev, mq);
497                                break;
498
499                        case MAPLE_RESPONSE_DEVINFO:
500                                maple_response_devinfo(dev, recvbuf);
501                                break;
502
503                        case MAPLE_RESPONSE_DATATRF:
504                                if (dev->callback)
505                                        dev->callback(mq);
506                                break;
507
508                        case MAPLE_RESPONSE_FILEERR:
509                        case MAPLE_RESPONSE_AGAIN:
510                        case MAPLE_RESPONSE_BADCMD:
511                        case MAPLE_RESPONSE_BADFUNC:
512                                printk(KERN_DEBUG
513                                       "Maple non-fatal error 0x%X\n",
514                                       code);
515                                break;
516
517                        case MAPLE_RESPONSE_ALLINFO:
518                                printk(KERN_DEBUG
519                                       "Maple - extended device information not supported\n");
520                                break;
521
522                        case MAPLE_RESPONSE_OK:
523                                break;
524
525                        default:
526                                break;
527                        }
528                }
529                INIT_LIST_HEAD(&maple_sentq);
530                if (scanning == 1) {
531                        maple_send();
532                        scanning = 2;
533                } else
534                        scanning = 0;
535
536                if (started == 0)
537                        started = 1;
538        }
539        maplebus_dma_reset();
540 }
541
542 static irqreturn_t maplebus_dma_interrupt(int irq, void *dev_id)
543 {
544        /* Load everything into the bottom half */
545        schedule_work(&maple_dma_process);
546        return IRQ_HANDLED;
547 }
548
549 static irqreturn_t maplebus_vblank_interrupt(int irq, void *dev_id)
550 {
551        schedule_work(&maple_vblank_process);
552        return IRQ_HANDLED;
553 }
554
555 static struct irqaction maple_dma_irq = {
556        .name = "maple bus DMA handler",
557        .handler = maplebus_dma_interrupt,
558        .flags = IRQF_SHARED,
559 };
560
561 static struct irqaction maple_vblank_irq = {
562        .name = "maple bus VBLANK handler",
563        .handler = maplebus_vblank_interrupt,
564        .flags = IRQF_SHARED,
565 };
566
567 static int maple_set_dma_interrupt_handler(void)
568 {
569        return setup_irq(HW_EVENT_MAPLE_DMA, &maple_dma_irq);
570 }
571
572 static int maple_set_vblank_interrupt_handler(void)
573 {
574        return setup_irq(HW_EVENT_VSYNC, &maple_vblank_irq);
575 }
576
577 static int maple_get_dma_buffer(void)
578 {
579        maple_sendbuf =
580            (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
581                                      MAPLE_DMA_PAGES);
582        if (!maple_sendbuf)
583                return -ENOMEM;
584        return 0;
585 }
586
587 static int match_maple_bus_driver(struct device *devptr,
588                                  struct device_driver *drvptr)
589 {
590        struct maple_driver *maple_drv;
591        struct maple_device *maple_dev;
592
593        maple_drv = container_of(drvptr, struct maple_driver, drv);
594        maple_dev = container_of(devptr, struct maple_device, dev);
595        /* Trap empty port case */
596        if (maple_dev->devinfo.function == 0xFFFFFFFF)
597                return 0;
598        else if (maple_dev->devinfo.function &
599                 be32_to_cpu(maple_drv->function))
600                return 1;
601        return 0;
602 }
603
604 static int maple_bus_uevent(struct device *dev, char **envp,
605                            int num_envp, char *buffer, int buffer_size)
606 {
607        return 0;
608 }
609
610 static void maple_bus_release(struct device *dev)
611 {
612 }
613
614 static struct maple_driver maple_dummy_driver = {
615        .drv = {
616                .name = "maple_dummy_driver",
617                .bus =  &maple_bus_type,
618        },
619 };
620
621 struct bus_type maple_bus_type = {
622        .name =         "maple",
623        .match =        match_maple_bus_driver,
624        .uevent =       maple_bus_uevent,
625 };
626 EXPORT_SYMBOL_GPL(maple_bus_type);
627
628 static struct device maple_bus = {
629        .bus_id = "maple",
630        .release = maple_bus_release,
631 };
632
633 static int __init maple_bus_init(void)
634 {
635        int retval, i;
636        struct maple_device *mdev[MAPLE_PORTS];
637        ctrl_outl(0, MAPLE_STATE);
638
639        retval = device_register(&maple_bus);
640        if (retval)
641                goto cleanup;
642
643        retval = bus_register(&maple_bus_type);
644        if (retval)
645                goto cleanup_device;
646
647        retval = driver_register(&maple_dummy_driver.drv);
648
649        if (retval)
650                goto cleanup_bus;
651
652        /* allocate memory for maple bus dma */
653        retval = maple_get_dma_buffer();
654        if (retval) {
655                printk(KERN_INFO
656                       "Maple bus: Failed to allocate Maple DMA buffers\n");
657                goto cleanup_basic;
658        }
659
660        /* set up DMA interrupt handler */
661        retval = maple_set_dma_interrupt_handler();
662        if (retval) {
663                printk(KERN_INFO
664                       "Maple bus: Failed to grab maple DMA IRQ\n");
665                goto cleanup_dma;
666        }
667
668        /* set up VBLANK interrupt handler */
669        retval = maple_set_vblank_interrupt_handler();
670        if (retval) {
671                printk(KERN_INFO "Maple bus: Failed to grab VBLANK IRQ\n");
672                goto cleanup_irq;
673        }
674
675        maple_queue_cache =
676            kmem_cache_create("maple_queue_cache", 0x400, 0,
677                              SLAB_HWCACHE_ALIGN, NULL);
678
679        if (!maple_queue_cache)
680                goto cleanup_bothirqs;
681
682        /* setup maple ports */
683        for (i = 0; i < MAPLE_PORTS; i++) {
684                mdev[i] = maple_alloc_dev(i, 0);
685                if (!mdev[i]) {
686                        while (i-- > 0)
687                                maple_free_dev(mdev[i]);
688                        goto cleanup_cache;
689                }
690                mdev[i]->registered = 0;
691                mdev[i]->mq->command = MAPLE_COMMAND_DEVINFO;
692                mdev[i]->mq->length = 0;
693                maple_attach_driver(mdev[i]);
694                maple_add_packet(mdev[i]->mq);
695                subdevice_map[i] = 0;
696        }
697
698        /* setup maplebus hardware */
699        maplebus_dma_reset();
700
701        /* initial detection */
702        maple_send();
703
704        maple_pnp_time = jiffies;
705
706        printk(KERN_INFO "Maple bus core now registered.\n");
707
708        return 0;
709
710 cleanup_cache:
711        kmem_cache_destroy(maple_queue_cache);
712
713 cleanup_bothirqs:
714        free_irq(HW_EVENT_VSYNC, 0);
715
716 cleanup_irq:
717        free_irq(HW_EVENT_MAPLE_DMA, 0);
718
719 cleanup_dma:
720        free_pages((unsigned long) maple_sendbuf, MAPLE_DMA_PAGES);
721
722 cleanup_basic:
723        driver_unregister(&maple_dummy_driver.drv);
724
725 cleanup_bus:
726        bus_unregister(&maple_bus_type);
727
728 cleanup_device:
729        device_unregister(&maple_bus);
730
731 cleanup:
732        printk(KERN_INFO "Maple bus registration failed\n");
733        return retval;
734 }
735 subsys_initcall(maple_bus_init);