freebsd-dev/sys/dev/drm/i915_irq.c
Robert Noland a84a56f28b Some more cleanups for vblank code on Intel.
The Intel 2d driver calls modeset before reinstalling the handler on
a vt switch.  This means that vblank status ends up getting cleared
after it has been setup.  Restore saved values for the pipestat registers
rather than just wiping them out.

MFC after:	3 days
2009-06-25 18:27:08 +00:00

550 lines
15 KiB
C

/* i915_irq.c -- IRQ support for the I915 -*- linux-c -*-
*/
/*-
* Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "dev/drm/drmP.h"
#include "dev/drm/drm.h"
#include "dev/drm/i915_drm.h"
#include "dev/drm/i915_drv.h"
#define MAX_NOPID ((u32)~0)
/**
* Interrupts that are always left unmasked.
*
* Since pipe events are edge-triggered from the PIPESTAT register to IIR,
* we leave them always unmasked in IMR and then control enabling them through
* PIPESTAT alone.
*/
#define I915_INTERRUPT_ENABLE_FIX (I915_DISPLAY_PIPE_A_EVENT_INTERRUPT | \
I915_DISPLAY_PIPE_B_EVENT_INTERRUPT)
/** Interrupts that we mask and unmask at runtime. */
#define I915_INTERRUPT_ENABLE_VAR (I915_USER_INTERRUPT)
/** These are all of the interrupts used by the driver */
#define I915_INTERRUPT_ENABLE_MASK (I915_INTERRUPT_ENABLE_FIX | \
I915_INTERRUPT_ENABLE_VAR)
#define DRM_I915_VBLANK_PIPE_ALL (DRM_I915_VBLANK_PIPE_A | \
DRM_I915_VBLANK_PIPE_B)
static inline void
i915_enable_irq(drm_i915_private_t *dev_priv, u32 mask)
{
mask &= I915_INTERRUPT_ENABLE_VAR;
if ((dev_priv->irq_mask_reg & mask) != 0) {
dev_priv->irq_mask_reg &= ~mask;
I915_WRITE(IMR, dev_priv->irq_mask_reg);
(void) I915_READ(IMR);
}
}
static inline void
i915_disable_irq(drm_i915_private_t *dev_priv, u32 mask)
{
mask &= I915_INTERRUPT_ENABLE_VAR;
if ((dev_priv->irq_mask_reg & mask) != mask) {
dev_priv->irq_mask_reg |= mask;
I915_WRITE(IMR, dev_priv->irq_mask_reg);
(void) I915_READ(IMR);
}
}
static inline u32
i915_pipestat(int pipe)
{
if (pipe == 0)
return PIPEASTAT;
if (pipe == 1)
return PIPEBSTAT;
return -EINVAL;
}
void
i915_enable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask)
{
if ((dev_priv->pipestat[pipe] & mask) != mask) {
u32 reg = i915_pipestat(pipe);
dev_priv->pipestat[pipe] |= mask;
/* Enable the interrupt, clear any pending status */
I915_WRITE(reg, dev_priv->pipestat[pipe] | (mask >> 16));
(void) I915_READ(reg);
}
}
void
i915_disable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask)
{
if ((dev_priv->pipestat[pipe] & mask) != 0) {
u32 reg = i915_pipestat(pipe);
dev_priv->pipestat[pipe] &= ~mask;
I915_WRITE(reg, dev_priv->pipestat[pipe]);
(void) I915_READ(reg);
}
}
/**
* i915_pipe_enabled - check if a pipe is enabled
* @dev: DRM device
* @pipe: pipe to check
*
* Reading certain registers when the pipe is disabled can hang the chip.
* Use this routine to make sure the PLL is running and the pipe is active
* before reading such registers if unsure.
*/
static int
i915_pipe_enabled(struct drm_device *dev, int pipe)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
unsigned long pipeconf = pipe ? PIPEBCONF : PIPEACONF;
if (I915_READ(pipeconf) & PIPEACONF_ENABLE)
return 1;
return 0;
}
/* Called from drm generic code, passed a 'crtc', which
* we use as a pipe index
*/
u32 i915_get_vblank_counter(struct drm_device *dev, int pipe)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
unsigned long high_frame;
unsigned long low_frame;
u32 high1, high2, low, count;
high_frame = pipe ? PIPEBFRAMEHIGH : PIPEAFRAMEHIGH;
low_frame = pipe ? PIPEBFRAMEPIXEL : PIPEAFRAMEPIXEL;
if (!i915_pipe_enabled(dev, pipe)) {
DRM_DEBUG("trying to get vblank count for disabled pipe %d\n", pipe);
return 0;
}
/*
* High & low register fields aren't synchronized, so make sure
* we get a low value that's stable across two reads of the high
* register.
*/
do {
high1 = ((I915_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
PIPE_FRAME_HIGH_SHIFT);
low = ((I915_READ(low_frame) & PIPE_FRAME_LOW_MASK) >>
PIPE_FRAME_LOW_SHIFT);
high2 = ((I915_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
PIPE_FRAME_HIGH_SHIFT);
} while (high1 != high2);
count = (high1 << 8) | low;
return count;
}
u32 g45_get_vblank_counter(struct drm_device *dev, int pipe)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
int reg = pipe ? PIPEB_FRMCOUNT_GM45 : PIPEA_FRMCOUNT_GM45;
if (!i915_pipe_enabled(dev, pipe)) {
DRM_DEBUG("trying to get vblank count for disabled pipe %d\n", pipe);
return 0;
}
return I915_READ(reg);
}
irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
{
struct drm_device *dev = (struct drm_device *) arg;
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
u32 iir, new_iir;
u32 pipea_stats, pipeb_stats;
u32 vblank_status;
u32 vblank_enable;
int irq_received;
iir = I915_READ(IIR);
if (IS_I965G(dev)) {
vblank_status = PIPE_START_VBLANK_INTERRUPT_STATUS;
vblank_enable = PIPE_START_VBLANK_INTERRUPT_ENABLE;
} else {
vblank_status = I915_VBLANK_INTERRUPT_STATUS;
vblank_enable = I915_VBLANK_INTERRUPT_ENABLE;
}
for (;;) {
irq_received = iir != 0;
/* Can't rely on pipestat interrupt bit in iir as it might
* have been cleared after the pipestat interrupt was received.
* It doesn't set the bit in iir again, but it still produces
* interrupts (for non-MSI).
*/
DRM_SPINLOCK(&dev_priv->user_irq_lock);
pipea_stats = I915_READ(PIPEASTAT);
pipeb_stats = I915_READ(PIPEBSTAT);
/*
* Clear the PIPE(A|B)STAT regs before the IIR
*/
if (pipea_stats & 0x8000ffff) {
I915_WRITE(PIPEASTAT, pipea_stats);
irq_received = 1;
}
if (pipeb_stats & 0x8000ffff) {
I915_WRITE(PIPEBSTAT, pipeb_stats);
irq_received = 1;
}
DRM_SPINUNLOCK(&dev_priv->user_irq_lock);
if (!irq_received)
break;
I915_WRITE(IIR, iir);
new_iir = I915_READ(IIR); /* Flush posted writes */
if (dev_priv->sarea_priv)
dev_priv->sarea_priv->last_dispatch =
READ_BREADCRUMB(dev_priv);
if (iir & I915_USER_INTERRUPT) {
DRM_WAKEUP(&dev_priv->irq_queue);
}
if (pipea_stats & vblank_status)
drm_handle_vblank(dev, 0);
if (pipeb_stats & vblank_status)
drm_handle_vblank(dev, 1);
/* With MSI, interrupts are only generated when iir
* transitions from zero to nonzero. If another bit got
* set while we were handling the existing iir bits, then
* we would never get another interrupt.
*
* This is fine on non-MSI as well, as if we hit this path
* we avoid exiting the interrupt handler only to generate
* another one.
*
* Note that for MSI this could cause a stray interrupt report
* if an interrupt landed in the time between writing IIR and
* the posting read. This should be rare enough to never
* trigger the 99% of 100,000 interrupts test for disabling
* stray interrupts.
*/
iir = new_iir;
}
}
static int i915_emit_irq(struct drm_device * dev)
{
drm_i915_private_t *dev_priv = dev->dev_private;
RING_LOCALS;
i915_kernel_lost_context(dev);
if (++dev_priv->counter > 0x7FFFFFFFUL)
dev_priv->counter = 0;
if (dev_priv->sarea_priv)
dev_priv->sarea_priv->last_enqueue = dev_priv->counter;
DRM_DEBUG("emitting: %d\n", dev_priv->counter);
BEGIN_LP_RING(4);
OUT_RING(MI_STORE_DWORD_INDEX);
OUT_RING(I915_BREADCRUMB_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
OUT_RING(dev_priv->counter);
OUT_RING(MI_USER_INTERRUPT);
ADVANCE_LP_RING();
return dev_priv->counter;
}
void i915_user_irq_get(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
if (dev->irq_enabled == 0)
return;
DRM_DEBUG("\n");
DRM_SPINLOCK(&dev_priv->user_irq_lock);
if (++dev_priv->user_irq_refcount == 1)
i915_enable_irq(dev_priv, I915_USER_INTERRUPT);
DRM_SPINUNLOCK(&dev_priv->user_irq_lock);
}
void i915_user_irq_put(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
if (dev->irq_enabled == 0)
return;
DRM_SPINLOCK(&dev_priv->user_irq_lock);
KASSERT(dev_priv->user_irq_refcount > 0, ("invalid refcount"));
if (--dev_priv->user_irq_refcount == 0)
i915_disable_irq(dev_priv, I915_USER_INTERRUPT);
DRM_SPINUNLOCK(&dev_priv->user_irq_lock);
}
static int i915_wait_irq(struct drm_device * dev, int irq_nr)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
int ret = 0;
if (READ_BREADCRUMB(dev_priv) >= irq_nr) {
if (dev_priv->sarea_priv) {
dev_priv->sarea_priv->last_dispatch =
READ_BREADCRUMB(dev_priv);
}
return 0;
}
if (dev_priv->sarea_priv)
dev_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;
DRM_DEBUG("irq_nr=%d breadcrumb=%d\n", irq_nr,
READ_BREADCRUMB(dev_priv));
i915_user_irq_get(dev);
DRM_WAIT_ON(ret, dev_priv->irq_queue, 3 * DRM_HZ,
READ_BREADCRUMB(dev_priv) >= irq_nr);
i915_user_irq_put(dev);
if (ret == -ERESTART)
DRM_DEBUG("restarting syscall\n");
if (ret == -EBUSY) {
DRM_ERROR("EBUSY -- rec: %d emitted: %d\n",
READ_BREADCRUMB(dev_priv), (int)dev_priv->counter);
}
return ret;
}
/* Needs the lock as it touches the ring.
*/
int i915_irq_emit(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
drm_i915_private_t *dev_priv = dev->dev_private;
drm_i915_irq_emit_t *emit = data;
int result;
if (!dev_priv) {
DRM_ERROR("called with no initialization\n");
return -EINVAL;
}
RING_LOCK_TEST_WITH_RETURN(dev, file_priv);
result = i915_emit_irq(dev);
if (DRM_COPY_TO_USER(emit->irq_seq, &result, sizeof(int))) {
DRM_ERROR("copy_to_user\n");
return -EFAULT;
}
return 0;
}
/* Doesn't need the hardware lock.
*/
int i915_irq_wait(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
drm_i915_private_t *dev_priv = dev->dev_private;
drm_i915_irq_wait_t *irqwait = data;
if (!dev_priv) {
DRM_ERROR("called with no initialization\n");
return -EINVAL;
}
return i915_wait_irq(dev, irqwait->irq_seq);
}
/* Called from drm generic code, passed 'crtc' which
* we use as a pipe index
*/
int i915_enable_vblank(struct drm_device *dev, int pipe)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
if (!i915_pipe_enabled(dev, pipe))
return -EINVAL;
DRM_SPINLOCK(&dev_priv->user_irq_lock);
if (IS_I965G(dev))
i915_enable_pipestat(dev_priv, pipe,
PIPE_START_VBLANK_INTERRUPT_ENABLE);
else
i915_enable_pipestat(dev_priv, pipe,
PIPE_VBLANK_INTERRUPT_ENABLE);
DRM_SPINUNLOCK(&dev_priv->user_irq_lock);
return 0;
}
/* Called from drm generic code, passed 'crtc' which
* we use as a pipe index
*/
void i915_disable_vblank(struct drm_device *dev, int pipe)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
DRM_SPINLOCK(&dev_priv->user_irq_lock);
i915_disable_pipestat(dev_priv, pipe,
PIPE_VBLANK_INTERRUPT_ENABLE |
PIPE_START_VBLANK_INTERRUPT_ENABLE);
DRM_SPINUNLOCK(&dev_priv->user_irq_lock);
}
/* Set the vblank monitor pipe
*/
int i915_vblank_pipe_set(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
drm_i915_private_t *dev_priv = dev->dev_private;
if (!dev_priv) {
DRM_ERROR("called with no initialization\n");
return -EINVAL;
}
return 0;
}
int i915_vblank_pipe_get(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
drm_i915_private_t *dev_priv = dev->dev_private;
drm_i915_vblank_pipe_t *pipe = data;
if (!dev_priv) {
DRM_ERROR("called with no initialization\n");
return -EINVAL;
}
pipe->pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;
return 0;
}
/**
* Schedule buffer swap at given vertical blank.
*/
int i915_vblank_swap(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
/* The delayed swap mechanism was fundamentally racy, and has been
* removed. The model was that the client requested a delayed flip/swap
* from the kernel, then waited for vblank before continuing to perform
* rendering. The problem was that the kernel might wake the client
* up before it dispatched the vblank swap (since the lock has to be
* held while touching the ringbuffer), in which case the client would
* clear and start the next frame before the swap occurred, and
* flicker would occur in addition to likely missing the vblank.
*
* In the absence of this ioctl, userland falls back to a correct path
* of waiting for a vblank, then dispatching the swap on its own.
* Context switching to userland and back is plenty fast enough for
* meeting the requirements of vblank swapping.
*/
return -EINVAL;
}
/* drm_dma.h hooks
*/
void i915_driver_irq_preinstall(struct drm_device * dev)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
I915_WRITE(HWSTAM, 0xeffe);
I915_WRITE(PIPEASTAT, 0);
I915_WRITE(PIPEBSTAT, 0);
I915_WRITE(IMR, 0xffffffff);
I915_WRITE(IER, 0x0);
(void) I915_READ(IER);
}
int i915_driver_irq_postinstall(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
dev_priv->vblank_pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;
/* Unmask the interrupts that we always want on. */
dev_priv->irq_mask_reg = ~I915_INTERRUPT_ENABLE_FIX;
/* Disable pipe interrupt enables, clear pending pipe status */
I915_WRITE(PIPEASTAT, I915_READ(PIPEASTAT) & 0x8000ffff);
I915_WRITE(PIPEBSTAT, I915_READ(PIPEBSTAT) & 0x8000ffff);
/* Clear pending interrupt status */
I915_WRITE(IIR, I915_READ(IIR));
I915_WRITE(IER, I915_INTERRUPT_ENABLE_MASK);
I915_WRITE(IMR, dev_priv->irq_mask_reg);
I915_WRITE(PIPEASTAT, dev_priv->pipestat[0] |
(dev_priv->pipestat[0] >> 16));
I915_WRITE(PIPEBSTAT, dev_priv->pipestat[1] |
(dev_priv->pipestat[1] >> 16));
(void) I915_READ(IER);
return 0;
}
void i915_driver_irq_uninstall(struct drm_device * dev)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
if (!dev_priv)
return;
dev_priv->vblank_pipe = 0;
I915_WRITE(HWSTAM, 0xffffffff);
I915_WRITE(PIPEASTAT, 0);
I915_WRITE(PIPEBSTAT, 0);
I915_WRITE(IMR, 0xffffffff);
I915_WRITE(IER, 0x0);
I915_WRITE(PIPEASTAT, I915_READ(PIPEASTAT) & 0x8000ffff);
I915_WRITE(PIPEBSTAT, I915_READ(PIPEBSTAT) & 0x8000ffff);
I915_WRITE(IIR, I915_READ(IIR));
}