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 wait_queue_head_t wait_idle;
105 wait_queue_head_t wait_free;
107 struct timeval base_time;
109 struct pxa3xx_gcu_batch *free;
111 struct pxa3xx_gcu_batch *ready;
112 struct pxa3xx_gcu_batch *ready_last;
113 struct pxa3xx_gcu_batch *running;
116 static inline unsigned long
117 gc_readl(struct pxa3xx_gcu_priv *priv, unsigned int off)
119 return __raw_readl(priv->mmio_base + off);
123 gc_writel(struct pxa3xx_gcu_priv *priv, unsigned int off, unsigned long val)
125 __raw_writel(val, priv->mmio_base + off);
128 #define QPRINT(priv, level, msg) \
131 struct pxa3xx_gcu_shared *shared = priv->shared; \
132 u32 base = gc_readl(priv, REG_GCRBBR); \
134 do_gettimeofday(&tv); \
136 printk(level "%ld.%03ld.%03ld - %-17s: %-21s (%s, " \
138 "0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, " \
140 tv.tv_sec - priv->base_time.tv_sec, \
141 tv.tv_usec / 1000, tv.tv_usec % 1000, \
143 shared->hw_running ? "running" : " idle", \
144 gc_readl(priv, REG_GCISCR), \
145 gc_readl(priv, REG_GCRBBR), \
146 gc_readl(priv, REG_GCRBLR), \
147 (gc_readl(priv, REG_GCRBEXHR) - base) / 4, \
148 (gc_readl(priv, REG_GCRBHR) - base) / 4, \
149 (gc_readl(priv, REG_GCRBTR) - base) / 4); \
153 pxa3xx_gcu_reset(struct pxa3xx_gcu_priv *priv)
157 /* disable interrupts */
158 gc_writel(priv, REG_GCIECR, 0);
161 gc_writel(priv, REG_GCCR, GCCR_ABORT);
162 gc_writel(priv, REG_GCCR, 0);
164 memset(priv->shared, 0, SHARED_SIZE);
165 priv->shared->buffer_phys = priv->shared_phys;
166 priv->shared->magic = PXA3XX_GCU_SHARED_MAGIC;
168 do_gettimeofday(&priv->base_time);
170 /* set up the ring buffer pointers */
171 gc_writel(priv, REG_GCRBLR, 0);
172 gc_writel(priv, REG_GCRBBR, priv->shared_phys);
173 gc_writel(priv, REG_GCRBTR, priv->shared_phys);
175 /* enable all IRQs except EOB */
176 gc_writel(priv, REG_GCIECR, IE_ALL & ~IE_EOB);
180 dump_whole_state(struct pxa3xx_gcu_priv *priv)
182 struct pxa3xx_gcu_shared *sh = priv->shared;
183 u32 base = gc_readl(priv, REG_GCRBBR);
187 printk(KERN_DEBUG "== PXA3XX-GCU DUMP ==\n"
188 "%s, STATUS 0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, T %5ld\n",
189 sh->hw_running ? "running" : "idle ",
190 gc_readl(priv, REG_GCISCR),
191 gc_readl(priv, REG_GCRBBR),
192 gc_readl(priv, REG_GCRBLR),
193 (gc_readl(priv, REG_GCRBEXHR) - base) / 4,
194 (gc_readl(priv, REG_GCRBHR) - base) / 4,
195 (gc_readl(priv, REG_GCRBTR) - base) / 4);
199 flush_running(struct pxa3xx_gcu_priv *priv)
201 struct pxa3xx_gcu_batch *running = priv->running;
202 struct pxa3xx_gcu_batch *next;
205 next = running->next;
206 running->next = priv->free;
207 priv->free = running;
211 priv->running = NULL;
215 run_ready(struct pxa3xx_gcu_priv *priv)
217 unsigned int num = 0;
218 struct pxa3xx_gcu_shared *shared = priv->shared;
219 struct pxa3xx_gcu_batch *ready = priv->ready;
225 shared->buffer[num++] = 0x05000000;
228 shared->buffer[num++] = 0x00000001;
229 shared->buffer[num++] = ready->phys;
233 shared->buffer[num++] = 0x05000000;
234 priv->running = priv->ready;
235 priv->ready = priv->ready_last = NULL;
236 gc_writel(priv, REG_GCRBLR, 0);
237 shared->hw_running = 1;
239 /* ring base address */
240 gc_writel(priv, REG_GCRBBR, shared->buffer_phys);
242 /* ring tail address */
243 gc_writel(priv, REG_GCRBTR, shared->buffer_phys + num * 4);
246 gc_writel(priv, REG_GCRBLR, ((num + 63) & ~63) * 4);
250 pxa3xx_gcu_handle_irq(int irq, void *ctx)
252 struct pxa3xx_gcu_priv *priv = ctx;
253 struct pxa3xx_gcu_shared *shared = priv->shared;
254 u32 status = gc_readl(priv, REG_GCISCR) & IE_ALL;
261 spin_lock(&priv->spinlock);
262 shared->num_interrupts++;
264 if (status & IE_EEOB) {
268 wake_up_all(&priv->wait_free);
273 /* There is no more data prepared by the userspace.
274 * Set hw_running = 0 and wait for the next userspace
277 shared->hw_running = 0;
281 /* set ring buffer length to zero */
282 gc_writel(priv, REG_GCRBLR, 0);
284 wake_up_all(&priv->wait_idle);
290 dump_whole_state(priv);
293 /* Clear the interrupt */
294 gc_writel(priv, REG_GCISCR, status);
295 spin_unlock(&priv->spinlock);
301 pxa3xx_gcu_wait_idle(struct pxa3xx_gcu_priv *priv)
305 QDUMP("Waiting for idle...");
307 /* Does not need to be atomic. There's a lock in user space,
308 * but anyhow, this is just for statistics. */
309 priv->shared->num_wait_idle++;
311 while (priv->shared->hw_running) {
312 int num = priv->shared->num_interrupts;
313 u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
315 ret = wait_event_interruptible_timeout(priv->wait_idle,
316 !priv->shared->hw_running, HZ*4);
321 if (gc_readl(priv, REG_GCRBEXHR) == rbexhr &&
322 priv->shared->num_interrupts == num) {
335 pxa3xx_gcu_wait_free(struct pxa3xx_gcu_priv *priv)
339 QDUMP("Waiting for free...");
341 /* Does not need to be atomic. There's a lock in user space,
342 * but anyhow, this is just for statistics. */
343 priv->shared->num_wait_free++;
345 while (!priv->free) {
346 u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
348 ret = wait_event_interruptible_timeout(priv->wait_free,
357 if (gc_readl(priv, REG_GCRBEXHR) == rbexhr) {
369 /* Misc device layer */
371 static inline struct pxa3xx_gcu_priv *file_dev(struct file *file)
373 struct miscdevice *dev = file->private_data;
374 return container_of(dev, struct pxa3xx_gcu_priv, misc_dev);
378 pxa3xx_gcu_misc_write(struct file *file, const char *buff,
379 size_t count, loff_t *offp)
383 struct pxa3xx_gcu_batch *buffer;
384 struct pxa3xx_gcu_priv *priv = file_dev(file);
386 int words = count / 4;
388 /* Does not need to be atomic. There's a lock in user space,
389 * but anyhow, this is just for statistics. */
390 priv->shared->num_writes++;
392 priv->shared->num_words += words;
394 /* Last word reserved for batch buffer end command */
395 if (words >= PXA3XX_GCU_BATCH_WORDS)
398 /* Wait for a free buffer */
400 ret = pxa3xx_gcu_wait_free(priv);
406 * Get buffer from free list
408 spin_lock_irqsave(&priv->spinlock, flags);
411 priv->free = buffer->next;
413 spin_unlock_irqrestore(&priv->spinlock, flags);
416 /* Copy data from user into buffer */
417 ret = copy_from_user(buffer->ptr, buff, words * 4);
419 spin_lock_irqsave(&priv->spinlock, flags);
420 buffer->next = priv->free;
422 spin_unlock_irqrestore(&priv->spinlock, flags);
426 buffer->length = words;
428 /* Append batch buffer end command */
429 buffer->ptr[words] = 0x01000000;
432 * Add buffer to ready list
434 spin_lock_irqsave(&priv->spinlock, flags);
439 BUG_ON(priv->ready_last == NULL);
441 priv->ready_last->next = buffer;
443 priv->ready = buffer;
445 priv->ready_last = buffer;
447 if (!priv->shared->hw_running)
450 spin_unlock_irqrestore(&priv->spinlock, flags);
457 pxa3xx_gcu_misc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
460 struct pxa3xx_gcu_priv *priv = file_dev(file);
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 *file, struct vm_area_struct *vma)
479 unsigned int size = vma->vm_end - vma->vm_start;
480 struct pxa3xx_gcu_priv *priv = file_dev(file);
482 switch (vma->vm_pgoff) {
484 /* hand out the shared data area */
485 if (size != SHARED_SIZE)
488 return dma_mmap_coherent(NULL, vma,
489 priv->shared, priv->shared_phys, size);
491 case SHARED_SIZE >> PAGE_SHIFT:
492 /* hand out the MMIO base for direct register access
494 if (size != resource_size(priv->resource_mem))
497 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
499 return io_remap_pfn_range(vma, vma->vm_start,
500 priv->resource_mem->start >> PAGE_SHIFT,
501 size, vma->vm_page_prot);
508 #ifdef PXA3XX_GCU_DEBUG_TIMER
509 static struct timer_list pxa3xx_gcu_debug_timer;
511 static void pxa3xx_gcu_debug_timedout(unsigned long ptr)
513 struct pxa3xx_gcu_priv *priv = (struct pxa3xx_gcu_priv *) ptr;
515 QERROR("Timer DUMP");
517 /* init the timer structure */
518 init_timer(&pxa3xx_gcu_debug_timer);
519 pxa3xx_gcu_debug_timer.function = pxa3xx_gcu_debug_timedout;
520 pxa3xx_gcu_debug_timer.data = ptr;
521 pxa3xx_gcu_debug_timer.expires = jiffies + 5*HZ; /* one second */
523 add_timer(&pxa3xx_gcu_debug_timer);
526 static void pxa3xx_gcu_init_debug_timer(void)
528 pxa3xx_gcu_debug_timedout((unsigned long) &pxa3xx_gcu_debug_timer);
531 static inline void pxa3xx_gcu_init_debug_timer(void) {}
535 add_buffer(struct platform_device *dev,
536 struct pxa3xx_gcu_priv *priv)
538 struct pxa3xx_gcu_batch *buffer;
540 buffer = kzalloc(sizeof(struct pxa3xx_gcu_batch), GFP_KERNEL);
544 buffer->ptr = dma_alloc_coherent(&dev->dev, PXA3XX_GCU_BATCH_WORDS * 4,
545 &buffer->phys, GFP_KERNEL);
551 buffer->next = priv->free;
559 free_buffers(struct platform_device *dev,
560 struct pxa3xx_gcu_priv *priv)
562 struct pxa3xx_gcu_batch *next, *buffer = priv->free;
567 dma_free_coherent(&dev->dev, PXA3XX_GCU_BATCH_WORDS * 4,
568 buffer->ptr, buffer->phys);
578 static const struct file_operations misc_fops = {
579 .owner = THIS_MODULE,
580 .write = pxa3xx_gcu_misc_write,
581 .unlocked_ioctl = pxa3xx_gcu_misc_ioctl,
582 .mmap = pxa3xx_gcu_misc_mmap
585 static int pxa3xx_gcu_probe(struct platform_device *dev)
589 struct pxa3xx_gcu_priv *priv;
591 priv = kzalloc(sizeof(struct pxa3xx_gcu_priv), GFP_KERNEL);
595 for (i = 0; i < 8; i++) {
596 ret = add_buffer(dev, priv);
598 dev_err(&dev->dev, "failed to allocate DMA memory\n");
603 init_waitqueue_head(&priv->wait_idle);
604 init_waitqueue_head(&priv->wait_free);
605 spin_lock_init(&priv->spinlock);
607 /* we allocate the misc device structure as part of our own allocation,
608 * so we can get a pointer to our priv structure later on with
609 * container_of(). This isn't really necessary as we have a fixed minor
610 * number anyway, but this is to avoid statics. */
612 priv->misc_dev.minor = MISCDEV_MINOR,
613 priv->misc_dev.name = DRV_NAME,
614 priv->misc_dev.fops = &misc_fops,
616 /* register misc device */
617 ret = misc_register(&priv->misc_dev);
619 dev_err(&dev->dev, "misc_register() for minor %d failed\n",
624 /* handle IO resources */
625 r = platform_get_resource(dev, IORESOURCE_MEM, 0);
627 dev_err(&dev->dev, "no I/O memory resource defined\n");
629 goto err_misc_deregister;
632 if (!request_mem_region(r->start, resource_size(r), dev->name)) {
633 dev_err(&dev->dev, "failed to request I/O memory\n");
635 goto err_misc_deregister;
638 priv->mmio_base = ioremap_nocache(r->start, resource_size(r));
639 if (!priv->mmio_base) {
640 dev_err(&dev->dev, "failed to map I/O memory\n");
642 goto err_free_mem_region;
645 /* allocate dma memory */
646 priv->shared = dma_alloc_coherent(&dev->dev, SHARED_SIZE,
647 &priv->shared_phys, GFP_KERNEL);
650 dev_err(&dev->dev, "failed to allocate DMA memory\n");
655 /* enable the clock */
656 priv->clk = clk_get(&dev->dev, NULL);
657 if (IS_ERR(priv->clk)) {
658 dev_err(&dev->dev, "failed to get clock\n");
663 ret = clk_enable(priv->clk);
665 dev_err(&dev->dev, "failed to enable clock\n");
669 /* request the IRQ */
670 irq = platform_get_irq(dev, 0);
672 dev_err(&dev->dev, "no IRQ defined\n");
677 ret = request_irq(irq, pxa3xx_gcu_handle_irq,
680 dev_err(&dev->dev, "request_irq failed\n");
685 platform_set_drvdata(dev, priv);
686 priv->resource_mem = r;
687 pxa3xx_gcu_reset(priv);
688 pxa3xx_gcu_init_debug_timer();
690 dev_info(&dev->dev, "registered @0x%p, DMA 0x%p (%d bytes), IRQ %d\n",
691 (void *) r->start, (void *) priv->shared_phys,
696 clk_disable(priv->clk);
700 dma_free_coherent(&dev->dev, SHARED_SIZE,
701 priv->shared, priv->shared_phys);
704 iounmap(priv->mmio_base);
707 release_mem_region(r->start, resource_size(r));
710 misc_deregister(&priv->misc_dev);
713 free_buffers(dev, priv);
718 static int pxa3xx_gcu_remove(struct platform_device *dev)
720 struct pxa3xx_gcu_priv *priv = platform_get_drvdata(dev);
721 struct resource *r = priv->resource_mem;
723 pxa3xx_gcu_wait_idle(priv);
725 misc_deregister(&priv->misc_dev);
726 dma_free_coherent(&dev->dev, SHARED_SIZE,
727 priv->shared, priv->shared_phys);
728 iounmap(priv->mmio_base);
729 release_mem_region(r->start, resource_size(r));
730 clk_disable(priv->clk);
731 free_buffers(dev, priv);
737 static struct platform_driver pxa3xx_gcu_driver = {
738 .probe = pxa3xx_gcu_probe,
739 .remove = pxa3xx_gcu_remove,
741 .owner = THIS_MODULE,
746 module_platform_driver(pxa3xx_gcu_driver);
748 MODULE_DESCRIPTION("PXA3xx graphics controller unit driver");
749 MODULE_LICENSE("GPL");
750 MODULE_ALIAS_MISCDEV(MISCDEV_MINOR);
751 MODULE_AUTHOR("Janine Kropp <nin@directfb.org>, "
752 "Denis Oliver Kropp <dok@directfb.org>, "
753 "Daniel Mack <daniel@caiaq.de>");