2 * pxa3xx-gcu.c - Linux kernel module for PXA3xx graphics controllers
4 * This driver needs a DirectFB counterpart in user space, communication
5 * is handled via mmap()ed memory areas and an ioctl.
7 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
8 * Copyright (c) 2009 Janine Kropp <nin@directfb.org>
9 * Copyright (c) 2009 Denis Oliver Kropp <dok@directfb.org>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27 * WARNING: This controller is attached to System Bus 2 of the PXA which
28 * needs its arbiter to be enabled explicitly (CKENB & 1<<9).
29 * There is currently no way to do this from Linux, so you need to teach
30 * your bootloader for now.
33 #include <linux/module.h>
34 #include <linux/platform_device.h>
35 #include <linux/dma-mapping.h>
36 #include <linux/miscdevice.h>
37 #include <linux/interrupt.h>
38 #include <linux/spinlock.h>
39 #include <linux/uaccess.h>
40 #include <linux/ioctl.h>
41 #include <linux/delay.h>
42 #include <linux/sched.h>
43 #include <linux/slab.h>
44 #include <linux/clk.h>
48 #include "pxa3xx-gcu.h"
50 #define DRV_NAME "pxa3xx-gcu"
51 #define MISCDEV_MINOR 197
54 #define GCCR_SYNC_CLR (1 << 9)
55 #define GCCR_BP_RST (1 << 8)
56 #define GCCR_ABORT (1 << 6)
57 #define GCCR_STOP (1 << 4)
59 #define REG_GCISCR 0x04
60 #define REG_GCIECR 0x08
61 #define REG_GCRBBR 0x20
62 #define REG_GCRBLR 0x24
63 #define REG_GCRBHR 0x28
64 #define REG_GCRBTR 0x2C
65 #define REG_GCRBEXHR 0x30
67 #define IE_EOB (1 << 0)
68 #define IE_EEOB (1 << 5)
71 #define SHARED_SIZE PAGE_ALIGN(sizeof(struct pxa3xx_gcu_shared))
73 /* #define PXA3XX_GCU_DEBUG */
74 /* #define PXA3XX_GCU_DEBUG_TIMER */
76 #ifdef PXA3XX_GCU_DEBUG
79 QPRINT(priv, KERN_DEBUG, msg); \
82 #define QDUMP(msg) do {} while (0)
87 QPRINT(priv, KERN_ERR, msg); \
90 struct pxa3xx_gcu_batch {
91 struct pxa3xx_gcu_batch *next;
97 struct pxa3xx_gcu_priv {
98 void __iomem *mmio_base;
100 struct pxa3xx_gcu_shared *shared;
101 dma_addr_t shared_phys;
102 struct resource *resource_mem;
103 struct miscdevice misc_dev;
104 struct file_operations misc_fops;
105 wait_queue_head_t wait_idle;
106 wait_queue_head_t wait_free;
108 struct timeval base_time;
110 struct pxa3xx_gcu_batch *free;
112 struct pxa3xx_gcu_batch *ready;
113 struct pxa3xx_gcu_batch *ready_last;
114 struct pxa3xx_gcu_batch *running;
117 static inline unsigned long
118 gc_readl(struct pxa3xx_gcu_priv *priv, unsigned int off)
120 return __raw_readl(priv->mmio_base + off);
124 gc_writel(struct pxa3xx_gcu_priv *priv, unsigned int off, unsigned long val)
126 __raw_writel(val, priv->mmio_base + off);
129 #define QPRINT(priv, level, msg) \
132 struct pxa3xx_gcu_shared *shared = priv->shared; \
133 u32 base = gc_readl(priv, REG_GCRBBR); \
135 do_gettimeofday(&tv); \
137 printk(level "%ld.%03ld.%03ld - %-17s: %-21s (%s, " \
139 "0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, " \
141 tv.tv_sec - priv->base_time.tv_sec, \
142 tv.tv_usec / 1000, tv.tv_usec % 1000, \
144 shared->hw_running ? "running" : " idle", \
145 gc_readl(priv, REG_GCISCR), \
146 gc_readl(priv, REG_GCRBBR), \
147 gc_readl(priv, REG_GCRBLR), \
148 (gc_readl(priv, REG_GCRBEXHR) - base) / 4, \
149 (gc_readl(priv, REG_GCRBHR) - base) / 4, \
150 (gc_readl(priv, REG_GCRBTR) - base) / 4); \
154 pxa3xx_gcu_reset(struct pxa3xx_gcu_priv *priv)
158 /* disable interrupts */
159 gc_writel(priv, REG_GCIECR, 0);
162 gc_writel(priv, REG_GCCR, GCCR_ABORT);
163 gc_writel(priv, REG_GCCR, 0);
165 memset(priv->shared, 0, SHARED_SIZE);
166 priv->shared->buffer_phys = priv->shared_phys;
167 priv->shared->magic = PXA3XX_GCU_SHARED_MAGIC;
169 do_gettimeofday(&priv->base_time);
171 /* set up the ring buffer pointers */
172 gc_writel(priv, REG_GCRBLR, 0);
173 gc_writel(priv, REG_GCRBBR, priv->shared_phys);
174 gc_writel(priv, REG_GCRBTR, priv->shared_phys);
176 /* enable all IRQs except EOB */
177 gc_writel(priv, REG_GCIECR, IE_ALL & ~IE_EOB);
181 dump_whole_state(struct pxa3xx_gcu_priv *priv)
183 struct pxa3xx_gcu_shared *sh = priv->shared;
184 u32 base = gc_readl(priv, REG_GCRBBR);
188 printk(KERN_DEBUG "== PXA3XX-GCU DUMP ==\n"
189 "%s, STATUS 0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, T %5ld\n",
190 sh->hw_running ? "running" : "idle ",
191 gc_readl(priv, REG_GCISCR),
192 gc_readl(priv, REG_GCRBBR),
193 gc_readl(priv, REG_GCRBLR),
194 (gc_readl(priv, REG_GCRBEXHR) - base) / 4,
195 (gc_readl(priv, REG_GCRBHR) - base) / 4,
196 (gc_readl(priv, REG_GCRBTR) - base) / 4);
200 flush_running(struct pxa3xx_gcu_priv *priv)
202 struct pxa3xx_gcu_batch *running = priv->running;
203 struct pxa3xx_gcu_batch *next;
206 next = running->next;
207 running->next = priv->free;
208 priv->free = running;
212 priv->running = NULL;
216 run_ready(struct pxa3xx_gcu_priv *priv)
218 unsigned int num = 0;
219 struct pxa3xx_gcu_shared *shared = priv->shared;
220 struct pxa3xx_gcu_batch *ready = priv->ready;
226 shared->buffer[num++] = 0x05000000;
229 shared->buffer[num++] = 0x00000001;
230 shared->buffer[num++] = ready->phys;
234 shared->buffer[num++] = 0x05000000;
235 priv->running = priv->ready;
236 priv->ready = priv->ready_last = NULL;
237 gc_writel(priv, REG_GCRBLR, 0);
238 shared->hw_running = 1;
240 /* ring base address */
241 gc_writel(priv, REG_GCRBBR, shared->buffer_phys);
243 /* ring tail address */
244 gc_writel(priv, REG_GCRBTR, shared->buffer_phys + num * 4);
247 gc_writel(priv, REG_GCRBLR, ((num + 63) & ~63) * 4);
251 pxa3xx_gcu_handle_irq(int irq, void *ctx)
253 struct pxa3xx_gcu_priv *priv = ctx;
254 struct pxa3xx_gcu_shared *shared = priv->shared;
255 u32 status = gc_readl(priv, REG_GCISCR) & IE_ALL;
262 spin_lock(&priv->spinlock);
263 shared->num_interrupts++;
265 if (status & IE_EEOB) {
269 wake_up_all(&priv->wait_free);
274 /* There is no more data prepared by the userspace.
275 * Set hw_running = 0 and wait for the next userspace
278 shared->hw_running = 0;
282 /* set ring buffer length to zero */
283 gc_writel(priv, REG_GCRBLR, 0);
285 wake_up_all(&priv->wait_idle);
291 dump_whole_state(priv);
294 /* Clear the interrupt */
295 gc_writel(priv, REG_GCISCR, status);
296 spin_unlock(&priv->spinlock);
302 pxa3xx_gcu_wait_idle(struct pxa3xx_gcu_priv *priv)
306 QDUMP("Waiting for idle...");
308 /* Does not need to be atomic. There's a lock in user space,
309 * but anyhow, this is just for statistics. */
310 priv->shared->num_wait_idle++;
312 while (priv->shared->hw_running) {
313 int num = priv->shared->num_interrupts;
314 u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
316 ret = wait_event_interruptible_timeout(priv->wait_idle,
317 !priv->shared->hw_running, HZ*4);
325 if (gc_readl(priv, REG_GCRBEXHR) == rbexhr &&
326 priv->shared->num_interrupts == num) {
339 pxa3xx_gcu_wait_free(struct pxa3xx_gcu_priv *priv)
343 QDUMP("Waiting for free...");
345 /* Does not need to be atomic. There's a lock in user space,
346 * but anyhow, this is just for statistics. */
347 priv->shared->num_wait_free++;
349 while (!priv->free) {
350 u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
352 ret = wait_event_interruptible_timeout(priv->wait_free,
361 if (gc_readl(priv, REG_GCRBEXHR) == rbexhr) {
373 /* Misc device layer */
376 pxa3xx_gcu_misc_write(struct file *filp, const char *buff,
377 size_t count, loff_t *offp)
381 struct pxa3xx_gcu_batch *buffer;
382 struct pxa3xx_gcu_priv *priv =
383 container_of(filp->f_op, struct pxa3xx_gcu_priv, misc_fops);
385 int words = count / 4;
387 /* Does not need to be atomic. There's a lock in user space,
388 * but anyhow, this is just for statistics. */
389 priv->shared->num_writes++;
391 priv->shared->num_words += words;
393 /* Last word reserved for batch buffer end command */
394 if (words >= PXA3XX_GCU_BATCH_WORDS)
397 /* Wait for a free buffer */
399 ret = pxa3xx_gcu_wait_free(priv);
405 * Get buffer from free list
407 spin_lock_irqsave(&priv->spinlock, flags);
410 priv->free = buffer->next;
412 spin_unlock_irqrestore(&priv->spinlock, flags);
415 /* Copy data from user into buffer */
416 ret = copy_from_user(buffer->ptr, buff, words * 4);
418 spin_lock_irqsave(&priv->spinlock, flags);
419 buffer->next = priv->free;
421 spin_unlock_irqrestore(&priv->spinlock, flags);
425 buffer->length = words;
427 /* Append batch buffer end command */
428 buffer->ptr[words] = 0x01000000;
431 * Add buffer to ready list
433 spin_lock_irqsave(&priv->spinlock, flags);
438 BUG_ON(priv->ready_last == NULL);
440 priv->ready_last->next = buffer;
442 priv->ready = buffer;
444 priv->ready_last = buffer;
446 if (!priv->shared->hw_running)
449 spin_unlock_irqrestore(&priv->spinlock, flags);
456 pxa3xx_gcu_misc_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
459 struct pxa3xx_gcu_priv *priv =
460 container_of(filp->f_op, struct pxa3xx_gcu_priv, misc_fops);
463 case PXA3XX_GCU_IOCTL_RESET:
464 spin_lock_irqsave(&priv->spinlock, flags);
465 pxa3xx_gcu_reset(priv);
466 spin_unlock_irqrestore(&priv->spinlock, flags);
469 case PXA3XX_GCU_IOCTL_WAIT_IDLE:
470 return pxa3xx_gcu_wait_idle(priv);
477 pxa3xx_gcu_misc_mmap(struct file *filp, struct vm_area_struct *vma)
479 unsigned int size = vma->vm_end - vma->vm_start;
480 struct pxa3xx_gcu_priv *priv =
481 container_of(filp->f_op, struct pxa3xx_gcu_priv, misc_fops);
483 switch (vma->vm_pgoff) {
485 /* hand out the shared data area */
486 if (size != SHARED_SIZE)
489 return dma_mmap_coherent(NULL, vma,
490 priv->shared, priv->shared_phys, size);
492 case SHARED_SIZE >> PAGE_SHIFT:
493 /* hand out the MMIO base for direct register access
495 if (size != resource_size(priv->resource_mem))
498 vma->vm_flags |= VM_IO;
499 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
501 return io_remap_pfn_range(vma, vma->vm_start,
502 priv->resource_mem->start >> PAGE_SHIFT,
503 size, vma->vm_page_prot);
510 #ifdef PXA3XX_GCU_DEBUG_TIMER
511 static struct timer_list pxa3xx_gcu_debug_timer;
513 static void pxa3xx_gcu_debug_timedout(unsigned long ptr)
515 struct pxa3xx_gcu_priv *priv = (struct pxa3xx_gcu_priv *) ptr;
517 QERROR("Timer DUMP");
519 /* init the timer structure */
520 init_timer(&pxa3xx_gcu_debug_timer);
521 pxa3xx_gcu_debug_timer.function = pxa3xx_gcu_debug_timedout;
522 pxa3xx_gcu_debug_timer.data = ptr;
523 pxa3xx_gcu_debug_timer.expires = jiffies + 5*HZ; /* one second */
525 add_timer(&pxa3xx_gcu_debug_timer);
528 static void pxa3xx_gcu_init_debug_timer(void)
530 pxa3xx_gcu_debug_timedout((unsigned long) &pxa3xx_gcu_debug_timer);
533 static inline void pxa3xx_gcu_init_debug_timer(void) {}
537 add_buffer(struct platform_device *dev,
538 struct pxa3xx_gcu_priv *priv)
540 struct pxa3xx_gcu_batch *buffer;
542 buffer = kzalloc(sizeof(struct pxa3xx_gcu_batch), GFP_KERNEL);
546 buffer->ptr = dma_alloc_coherent(&dev->dev, PXA3XX_GCU_BATCH_WORDS * 4,
547 &buffer->phys, GFP_KERNEL);
553 buffer->next = priv->free;
561 free_buffers(struct platform_device *dev,
562 struct pxa3xx_gcu_priv *priv)
564 struct pxa3xx_gcu_batch *next, *buffer = priv->free;
569 dma_free_coherent(&dev->dev, PXA3XX_GCU_BATCH_WORDS * 4,
570 buffer->ptr, buffer->phys);
581 pxa3xx_gcu_probe(struct platform_device *dev)
585 struct pxa3xx_gcu_priv *priv;
587 priv = kzalloc(sizeof(struct pxa3xx_gcu_priv), GFP_KERNEL);
591 for (i = 0; i < 8; i++) {
592 ret = add_buffer(dev, priv);
594 dev_err(&dev->dev, "failed to allocate DMA memory\n");
599 init_waitqueue_head(&priv->wait_idle);
600 init_waitqueue_head(&priv->wait_free);
601 spin_lock_init(&priv->spinlock);
603 /* we allocate the misc device structure as part of our own allocation,
604 * so we can get a pointer to our priv structure later on with
605 * container_of(). This isn't really necessary as we have a fixed minor
606 * number anyway, but this is to avoid statics. */
608 priv->misc_fops.owner = THIS_MODULE;
609 priv->misc_fops.write = pxa3xx_gcu_misc_write;
610 priv->misc_fops.unlocked_ioctl = pxa3xx_gcu_misc_ioctl;
611 priv->misc_fops.mmap = pxa3xx_gcu_misc_mmap;
613 priv->misc_dev.minor = MISCDEV_MINOR,
614 priv->misc_dev.name = DRV_NAME,
615 priv->misc_dev.fops = &priv->misc_fops,
617 /* register misc device */
618 ret = misc_register(&priv->misc_dev);
620 dev_err(&dev->dev, "misc_register() for minor %d failed\n",
625 /* handle IO resources */
626 r = platform_get_resource(dev, IORESOURCE_MEM, 0);
628 dev_err(&dev->dev, "no I/O memory resource defined\n");
630 goto err_misc_deregister;
633 if (!request_mem_region(r->start, resource_size(r), dev->name)) {
634 dev_err(&dev->dev, "failed to request I/O memory\n");
636 goto err_misc_deregister;
639 priv->mmio_base = ioremap_nocache(r->start, resource_size(r));
640 if (!priv->mmio_base) {
641 dev_err(&dev->dev, "failed to map I/O memory\n");
643 goto err_free_mem_region;
646 /* allocate dma memory */
647 priv->shared = dma_alloc_coherent(&dev->dev, SHARED_SIZE,
648 &priv->shared_phys, GFP_KERNEL);
651 dev_err(&dev->dev, "failed to allocate DMA memory\n");
656 /* enable the clock */
657 priv->clk = clk_get(&dev->dev, NULL);
658 if (IS_ERR(priv->clk)) {
659 dev_err(&dev->dev, "failed to get clock\n");
664 ret = clk_enable(priv->clk);
666 dev_err(&dev->dev, "failed to enable clock\n");
670 /* request the IRQ */
671 irq = platform_get_irq(dev, 0);
673 dev_err(&dev->dev, "no IRQ defined\n");
678 ret = request_irq(irq, pxa3xx_gcu_handle_irq,
681 dev_err(&dev->dev, "request_irq failed\n");
686 platform_set_drvdata(dev, priv);
687 priv->resource_mem = r;
688 pxa3xx_gcu_reset(priv);
689 pxa3xx_gcu_init_debug_timer();
691 dev_info(&dev->dev, "registered @0x%p, DMA 0x%p (%d bytes), IRQ %d\n",
692 (void *) r->start, (void *) priv->shared_phys,
697 clk_disable(priv->clk);
701 dma_free_coherent(&dev->dev, SHARED_SIZE,
702 priv->shared, priv->shared_phys);
705 iounmap(priv->mmio_base);
708 release_mem_region(r->start, resource_size(r));
711 misc_deregister(&priv->misc_dev);
714 platform_set_drvdata(dev, NULL);
715 free_buffers(dev, priv);
721 pxa3xx_gcu_remove(struct platform_device *dev)
723 struct pxa3xx_gcu_priv *priv = platform_get_drvdata(dev);
724 struct resource *r = priv->resource_mem;
726 pxa3xx_gcu_wait_idle(priv);
728 misc_deregister(&priv->misc_dev);
729 dma_free_coherent(&dev->dev, SHARED_SIZE,
730 priv->shared, priv->shared_phys);
731 iounmap(priv->mmio_base);
732 release_mem_region(r->start, resource_size(r));
733 platform_set_drvdata(dev, NULL);
734 clk_disable(priv->clk);
735 free_buffers(dev, priv);
741 static struct platform_driver pxa3xx_gcu_driver = {
742 .probe = pxa3xx_gcu_probe,
743 .remove = __devexit_p(pxa3xx_gcu_remove),
745 .owner = THIS_MODULE,
751 pxa3xx_gcu_init(void)
753 return platform_driver_register(&pxa3xx_gcu_driver);
757 pxa3xx_gcu_exit(void)
759 platform_driver_unregister(&pxa3xx_gcu_driver);
762 module_init(pxa3xx_gcu_init);
763 module_exit(pxa3xx_gcu_exit);
765 MODULE_DESCRIPTION("PXA3xx graphics controller unit driver");
766 MODULE_LICENSE("GPL");
767 MODULE_ALIAS_MISCDEV(MISCDEV_MINOR);
768 MODULE_AUTHOR("Janine Kropp <nin@directfb.org>, "
769 "Denis Oliver Kropp <dok@directfb.org>, "
770 "Daniel Mack <daniel@caiaq.de>");