1 /* i915_irq.c -- IRQ support for the I915 -*- linux-c -*-
4 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
22 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
23 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
24 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
25 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
33 #include "intel_drv.h"
35 #define MAX_NOPID ((u32)~0)
38 * Interrupts that are always left unmasked.
40 * Since pipe events are edge-triggered from the PIPESTAT register to IIR,
41 * we leave them always unmasked in IMR and then control enabling them through
44 #define I915_INTERRUPT_ENABLE_FIX (I915_ASLE_INTERRUPT | \
45 I915_DISPLAY_PIPE_A_EVENT_INTERRUPT | \
46 I915_DISPLAY_PIPE_B_EVENT_INTERRUPT)
48 /** Interrupts that we mask and unmask at runtime. */
49 #define I915_INTERRUPT_ENABLE_VAR (I915_USER_INTERRUPT)
51 /** These are all of the interrupts used by the driver */
52 #define I915_INTERRUPT_ENABLE_MASK (I915_INTERRUPT_ENABLE_FIX | \
53 I915_INTERRUPT_ENABLE_VAR)
55 #define I915_PIPE_VBLANK_STATUS (PIPE_START_VBLANK_INTERRUPT_STATUS |\
56 PIPE_VBLANK_INTERRUPT_STATUS)
58 #define I915_PIPE_VBLANK_ENABLE (PIPE_START_VBLANK_INTERRUPT_ENABLE |\
59 PIPE_VBLANK_INTERRUPT_ENABLE)
61 #define DRM_I915_VBLANK_PIPE_ALL (DRM_I915_VBLANK_PIPE_A | \
62 DRM_I915_VBLANK_PIPE_B)
65 i915_enable_irq(drm_i915_private_t *dev_priv, u32 mask)
67 if ((dev_priv->irq_mask_reg & mask) != 0) {
68 dev_priv->irq_mask_reg &= ~mask;
69 I915_WRITE(IMR, dev_priv->irq_mask_reg);
70 (void) I915_READ(IMR);
75 i915_disable_irq(drm_i915_private_t *dev_priv, u32 mask)
77 if ((dev_priv->irq_mask_reg & mask) != mask) {
78 dev_priv->irq_mask_reg |= mask;
79 I915_WRITE(IMR, dev_priv->irq_mask_reg);
80 (void) I915_READ(IMR);
85 i915_pipestat(int pipe)
95 i915_enable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask)
97 if ((dev_priv->pipestat[pipe] & mask) != mask) {
98 u32 reg = i915_pipestat(pipe);
100 dev_priv->pipestat[pipe] |= mask;
101 /* Enable the interrupt, clear any pending status */
102 I915_WRITE(reg, dev_priv->pipestat[pipe] | (mask >> 16));
103 (void) I915_READ(reg);
108 i915_disable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask)
110 if ((dev_priv->pipestat[pipe] & mask) != 0) {
111 u32 reg = i915_pipestat(pipe);
113 dev_priv->pipestat[pipe] &= ~mask;
114 I915_WRITE(reg, dev_priv->pipestat[pipe]);
115 (void) I915_READ(reg);
120 * i915_pipe_enabled - check if a pipe is enabled
122 * @pipe: pipe to check
124 * Reading certain registers when the pipe is disabled can hang the chip.
125 * Use this routine to make sure the PLL is running and the pipe is active
126 * before reading such registers if unsure.
129 i915_pipe_enabled(struct drm_device *dev, int pipe)
131 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
132 unsigned long pipeconf = pipe ? PIPEBCONF : PIPEACONF;
134 if (I915_READ(pipeconf) & PIPEACONF_ENABLE)
140 /* Called from drm generic code, passed a 'crtc', which
141 * we use as a pipe index
143 u32 i915_get_vblank_counter(struct drm_device *dev, int pipe)
145 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
146 unsigned long high_frame;
147 unsigned long low_frame;
148 u32 high1, high2, low, count;
150 high_frame = pipe ? PIPEBFRAMEHIGH : PIPEAFRAMEHIGH;
151 low_frame = pipe ? PIPEBFRAMEPIXEL : PIPEAFRAMEPIXEL;
153 if (!i915_pipe_enabled(dev, pipe)) {
154 DRM_ERROR("trying to get vblank count for disabled pipe %d\n", pipe);
159 * High & low register fields aren't synchronized, so make sure
160 * we get a low value that's stable across two reads of the high
164 high1 = ((I915_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
165 PIPE_FRAME_HIGH_SHIFT);
166 low = ((I915_READ(low_frame) & PIPE_FRAME_LOW_MASK) >>
167 PIPE_FRAME_LOW_SHIFT);
168 high2 = ((I915_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
169 PIPE_FRAME_HIGH_SHIFT);
170 } while (high1 != high2);
172 count = (high1 << 8) | low;
177 irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
179 struct drm_device *dev = (struct drm_device *) arg;
180 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
181 struct drm_i915_master_private *master_priv;
183 u32 pipea_stats, pipeb_stats;
187 unsigned long irqflags;
191 atomic_inc(&dev_priv->irq_received);
193 iir = I915_READ(IIR);
196 vblank_status = I915_START_VBLANK_INTERRUPT_STATUS;
197 vblank_enable = PIPE_START_VBLANK_INTERRUPT_ENABLE;
199 vblank_status = I915_VBLANK_INTERRUPT_STATUS;
200 vblank_enable = I915_VBLANK_INTERRUPT_ENABLE;
204 irq_received = iir != 0;
206 /* Can't rely on pipestat interrupt bit in iir as it might
207 * have been cleared after the pipestat interrupt was received.
208 * It doesn't set the bit in iir again, but it still produces
209 * interrupts (for non-MSI).
211 spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
212 pipea_stats = I915_READ(PIPEASTAT);
213 pipeb_stats = I915_READ(PIPEBSTAT);
216 * Clear the PIPE(A|B)STAT regs before the IIR
218 if (pipea_stats & 0x8000ffff) {
219 I915_WRITE(PIPEASTAT, pipea_stats);
223 if (pipeb_stats & 0x8000ffff) {
224 I915_WRITE(PIPEBSTAT, pipeb_stats);
227 spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
234 I915_WRITE(IIR, iir);
235 new_iir = I915_READ(IIR); /* Flush posted writes */
237 if (dev->primary->master) {
238 master_priv = dev->primary->master->driver_priv;
239 if (master_priv->sarea_priv)
240 master_priv->sarea_priv->last_dispatch =
241 READ_BREADCRUMB(dev_priv);
244 if (iir & I915_USER_INTERRUPT) {
245 dev_priv->mm.irq_gem_seqno = i915_get_gem_seqno(dev);
246 DRM_WAKEUP(&dev_priv->irq_queue);
249 if (pipea_stats & vblank_status) {
251 drm_handle_vblank(dev, 0);
254 if (pipeb_stats & vblank_status) {
256 drm_handle_vblank(dev, 1);
259 if ((pipeb_stats & I915_LEGACY_BLC_EVENT_STATUS) ||
260 (iir & I915_ASLE_INTERRUPT))
261 opregion_asle_intr(dev);
263 /* With MSI, interrupts are only generated when iir
264 * transitions from zero to nonzero. If another bit got
265 * set while we were handling the existing iir bits, then
266 * we would never get another interrupt.
268 * This is fine on non-MSI as well, as if we hit this path
269 * we avoid exiting the interrupt handler only to generate
272 * Note that for MSI this could cause a stray interrupt report
273 * if an interrupt landed in the time between writing IIR and
274 * the posting read. This should be rare enough to never
275 * trigger the 99% of 100,000 interrupts test for disabling
284 static int i915_emit_irq(struct drm_device * dev)
286 drm_i915_private_t *dev_priv = dev->dev_private;
287 struct drm_i915_master_private *master_priv = dev->primary->master->driver_priv;
290 i915_kernel_lost_context(dev);
295 if (dev_priv->counter > 0x7FFFFFFFUL)
296 dev_priv->counter = 1;
297 if (master_priv->sarea_priv)
298 master_priv->sarea_priv->last_enqueue = dev_priv->counter;
301 OUT_RING(MI_STORE_DWORD_INDEX);
302 OUT_RING(I915_BREADCRUMB_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
303 OUT_RING(dev_priv->counter);
304 OUT_RING(MI_USER_INTERRUPT);
307 return dev_priv->counter;
310 void i915_user_irq_get(struct drm_device *dev)
312 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
313 unsigned long irqflags;
315 spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
316 if (dev->irq_enabled && (++dev_priv->user_irq_refcount == 1))
317 i915_enable_irq(dev_priv, I915_USER_INTERRUPT);
318 spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
321 void i915_user_irq_put(struct drm_device *dev)
323 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
324 unsigned long irqflags;
326 spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
327 BUG_ON(dev->irq_enabled && dev_priv->user_irq_refcount <= 0);
328 if (dev->irq_enabled && (--dev_priv->user_irq_refcount == 0))
329 i915_disable_irq(dev_priv, I915_USER_INTERRUPT);
330 spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
333 static int i915_wait_irq(struct drm_device * dev, int irq_nr)
335 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
336 struct drm_i915_master_private *master_priv = dev->primary->master->driver_priv;
339 DRM_DEBUG("irq_nr=%d breadcrumb=%d\n", irq_nr,
340 READ_BREADCRUMB(dev_priv));
342 if (READ_BREADCRUMB(dev_priv) >= irq_nr) {
343 if (master_priv->sarea_priv)
344 master_priv->sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
348 if (master_priv->sarea_priv)
349 master_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;
351 i915_user_irq_get(dev);
352 DRM_WAIT_ON(ret, dev_priv->irq_queue, 3 * DRM_HZ,
353 READ_BREADCRUMB(dev_priv) >= irq_nr);
354 i915_user_irq_put(dev);
357 DRM_ERROR("EBUSY -- rec: %d emitted: %d\n",
358 READ_BREADCRUMB(dev_priv), (int)dev_priv->counter);
364 /* Needs the lock as it touches the ring.
366 int i915_irq_emit(struct drm_device *dev, void *data,
367 struct drm_file *file_priv)
369 drm_i915_private_t *dev_priv = dev->dev_private;
370 drm_i915_irq_emit_t *emit = data;
373 RING_LOCK_TEST_WITH_RETURN(dev, file_priv);
376 DRM_ERROR("called with no initialization\n");
379 mutex_lock(&dev->struct_mutex);
380 result = i915_emit_irq(dev);
381 mutex_unlock(&dev->struct_mutex);
383 if (DRM_COPY_TO_USER(emit->irq_seq, &result, sizeof(int))) {
384 DRM_ERROR("copy_to_user\n");
391 /* Doesn't need the hardware lock.
393 int i915_irq_wait(struct drm_device *dev, void *data,
394 struct drm_file *file_priv)
396 drm_i915_private_t *dev_priv = dev->dev_private;
397 drm_i915_irq_wait_t *irqwait = data;
400 DRM_ERROR("called with no initialization\n");
404 return i915_wait_irq(dev, irqwait->irq_seq);
407 /* Called from drm generic code, passed 'crtc' which
408 * we use as a pipe index
410 int i915_enable_vblank(struct drm_device *dev, int pipe)
412 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
413 unsigned long irqflags;
414 int pipeconf_reg = (pipe == 0) ? PIPEACONF : PIPEBCONF;
417 pipeconf = I915_READ(pipeconf_reg);
418 if (!(pipeconf & PIPEACONF_ENABLE))
421 spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
423 i915_enable_pipestat(dev_priv, pipe,
424 PIPE_START_VBLANK_INTERRUPT_ENABLE);
426 i915_enable_pipestat(dev_priv, pipe,
427 PIPE_VBLANK_INTERRUPT_ENABLE);
428 spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
432 /* Called from drm generic code, passed 'crtc' which
433 * we use as a pipe index
435 void i915_disable_vblank(struct drm_device *dev, int pipe)
437 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
438 unsigned long irqflags;
440 spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
441 i915_disable_pipestat(dev_priv, pipe,
442 PIPE_VBLANK_INTERRUPT_ENABLE |
443 PIPE_START_VBLANK_INTERRUPT_ENABLE);
444 spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
447 void i915_enable_interrupt (struct drm_device *dev)
449 struct drm_i915_private *dev_priv = dev->dev_private;
450 opregion_enable_asle(dev);
451 dev_priv->irq_enabled = 1;
455 /* Set the vblank monitor pipe
457 int i915_vblank_pipe_set(struct drm_device *dev, void *data,
458 struct drm_file *file_priv)
460 drm_i915_private_t *dev_priv = dev->dev_private;
463 DRM_ERROR("called with no initialization\n");
470 int i915_vblank_pipe_get(struct drm_device *dev, void *data,
471 struct drm_file *file_priv)
473 drm_i915_private_t *dev_priv = dev->dev_private;
474 drm_i915_vblank_pipe_t *pipe = data;
477 DRM_ERROR("called with no initialization\n");
481 pipe->pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;
487 * Schedule buffer swap at given vertical blank.
489 int i915_vblank_swap(struct drm_device *dev, void *data,
490 struct drm_file *file_priv)
492 /* The delayed swap mechanism was fundamentally racy, and has been
493 * removed. The model was that the client requested a delayed flip/swap
494 * from the kernel, then waited for vblank before continuing to perform
495 * rendering. The problem was that the kernel might wake the client
496 * up before it dispatched the vblank swap (since the lock has to be
497 * held while touching the ringbuffer), in which case the client would
498 * clear and start the next frame before the swap occurred, and
499 * flicker would occur in addition to likely missing the vblank.
501 * In the absence of this ioctl, userland falls back to a correct path
502 * of waiting for a vblank, then dispatching the swap on its own.
503 * Context switching to userland and back is plenty fast enough for
504 * meeting the requirements of vblank swapping.
511 void i915_driver_irq_preinstall(struct drm_device * dev)
513 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
515 atomic_set(&dev_priv->irq_received, 0);
517 I915_WRITE(HWSTAM, 0xeffe);
518 I915_WRITE(PIPEASTAT, 0);
519 I915_WRITE(PIPEBSTAT, 0);
520 I915_WRITE(IMR, 0xffffffff);
521 I915_WRITE(IER, 0x0);
522 (void) I915_READ(IER);
525 int i915_driver_irq_postinstall(struct drm_device *dev)
527 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
529 dev_priv->vblank_pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;
531 dev->max_vblank_count = 0xffffff; /* only 24 bits of frame count */
533 /* Unmask the interrupts that we always want on. */
534 dev_priv->irq_mask_reg = ~I915_INTERRUPT_ENABLE_FIX;
536 dev_priv->pipestat[0] = 0;
537 dev_priv->pipestat[1] = 0;
539 /* Disable pipe interrupt enables, clear pending pipe status */
540 I915_WRITE(PIPEASTAT, I915_READ(PIPEASTAT) & 0x8000ffff);
541 I915_WRITE(PIPEBSTAT, I915_READ(PIPEBSTAT) & 0x8000ffff);
542 /* Clear pending interrupt status */
543 I915_WRITE(IIR, I915_READ(IIR));
545 I915_WRITE(IER, I915_INTERRUPT_ENABLE_MASK);
546 I915_WRITE(IMR, dev_priv->irq_mask_reg);
547 (void) I915_READ(IER);
549 opregion_enable_asle(dev);
550 DRM_INIT_WAITQUEUE(&dev_priv->irq_queue);
555 void i915_driver_irq_uninstall(struct drm_device * dev)
557 drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
562 dev_priv->vblank_pipe = 0;
564 I915_WRITE(HWSTAM, 0xffffffff);
565 I915_WRITE(PIPEASTAT, 0);
566 I915_WRITE(PIPEBSTAT, 0);
567 I915_WRITE(IMR, 0xffffffff);
568 I915_WRITE(IER, 0x0);
570 I915_WRITE(PIPEASTAT, I915_READ(PIPEASTAT) & 0x8000ffff);
571 I915_WRITE(PIPEBSTAT, I915_READ(PIPEBSTAT) & 0x8000ffff);
572 I915_WRITE(IIR, I915_READ(IIR));