/**
* i915_reset - reset chip after a hang
* @dev: drm device to reset
*
* Reset the chip. Useful if a hang is detected. Returns zero on successful
* reset or otherwise an error code.
*
* Procedure is fairly simple:
* - reset the chip using the reset reg
* - re-init context state
* - re-init hardware status page
* - re-init ring buffer
* - re-init interrupt state
* - re-init display
*/
int i915_reset(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = dev->dev_private;
int ret;
if (!i915_try_reset)
return 0;
mutex_lock(&dev->struct_mutex);
i915_gem_reset(dev);
ret = -ENODEV;
if (get_seconds() - dev_priv->last_gpu_reset < 5)
DRM_ERROR("GPU hanging too fast, declaring wedged!\n");
else
ret = intel_gpu_reset(dev);
dev_priv->last_gpu_reset = get_seconds();
if (ret) {
DRM_ERROR("Failed to reset chip.\n");
mutex_unlock(&dev->struct_mutex);
return ret;
}
/* Ok, now get things going again... */
/*
* Everything depends on having the GTT running, so we need to start
* there. Fortunately we don't need to do this unless we reset the
* chip at a PCI level.
*
* Next we need to restore the context, but we don't use those
* yet either...
*
* Ring buffer needs to be re-initialized in the KMS case, or if X
* was running at the time of the reset (i.e. we weren't VT
* switched away).
*/
if (drm_core_check_feature(dev, DRIVER_MODESET) ||
!dev_priv->mm.suspended) {
struct intel_ring_buffer *ring;
int i;
dev_priv->mm.suspended = 0;
i915_gem_init_swizzling(dev);
for_each_ring(ring, dev_priv, i)
ring->init(ring);
i915_gem_context_init(dev);
i915_gem_init_ppgtt(dev);
/*
* It would make sense to re-init all the other hw state, at
* least the rps/rc6/emon init done within modeset_init_hw. For
* some unknown reason, this blows up my ilk, so don't.
*/
mutex_unlock(&dev->struct_mutex);
drm_irq_uninstall(dev);
drm_irq_install(dev);
} else {
mutex_unlock(&dev->struct_mutex);
}
return 0;
}
int
i915_reset(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = dev->dev_private;
/*
* We really should only reset the display subsystem if we actually
* need to
*/
bool need_display = true;
int ret;
if (!i915_try_reset)
return (0);
if (!sx_try_xlock(&dev->dev_struct_lock))
return (-EBUSY);
i915_gem_reset(dev);
ret = -ENODEV;
if (time_second - dev_priv->last_gpu_reset < 5) {
DRM_ERROR("GPU hanging too fast, declaring wedged!\n");
} else
ret = intel_gpu_reset(dev);
dev_priv->last_gpu_reset = time_second;
if (ret) {
DRM_ERROR("Failed to reset chip.\n");
DRM_UNLOCK(dev);
return (ret);
}
if (drm_core_check_feature(dev, DRIVER_MODESET) ||
!dev_priv->mm.suspended) {
dev_priv->mm.suspended = 0;
i915_gem_init_swizzling(dev);
dev_priv->rings[RCS].init(&dev_priv->rings[RCS]);
if (HAS_BSD(dev))
dev_priv->rings[VCS].init(&dev_priv->rings[VCS]);
if (HAS_BLT(dev))
dev_priv->rings[BCS].init(&dev_priv->rings[BCS]);
i915_gem_context_init(dev);
i915_gem_init_ppgtt(dev);
drm_irq_uninstall(dev);
drm_mode_config_reset(dev);
DRM_UNLOCK(dev);
drm_irq_install(dev);
DRM_LOCK(dev);
}
DRM_UNLOCK(dev);
if (need_display) {
sx_xlock(&dev->mode_config.mutex);
drm_helper_resume_force_mode(dev);
sx_xunlock(&dev->mode_config.mutex);
}
return (0);
}
