From db689c7b95613237cec904c3f6ee27e8c2bf7ce0 Mon Sep 17 00:00:00 2001 From: Jesse Barnes Date: Tue, 12 Jun 2007 10:44:21 -0700 Subject: Initial checkin of vblank rework. Code attempts to reduce the number of vblank interrupt in order to save power. --- linux-core/drmP.h | 12 +++++---- linux-core/drm_irq.c | 69 +++++++++++++++++++++++++++++++++++++++------------ linux-core/i915_drv.c | 5 ++-- 3 files changed, 63 insertions(+), 23 deletions(-) (limited to 'linux-core') diff --git a/linux-core/drmP.h b/linux-core/drmP.h index dd3a69df..c3f20311 100644 --- a/linux-core/drmP.h +++ b/linux-core/drmP.h @@ -627,8 +627,9 @@ struct drm_driver { int (*kernel_context_switch) (struct drm_device * dev, int old, int new); void (*kernel_context_switch_unlock) (struct drm_device * dev); - int (*vblank_wait) (struct drm_device * dev, unsigned int *sequence); - int (*vblank_wait2) (struct drm_device * dev, unsigned int *sequence); + u32 (*get_vblank_counter) (struct drm_device *dev, int crtc); + void (*enable_vblank) (struct drm_device *dev, int crtc); + void (*disable_vblank) (struct drm_device *dev, int crtc); int (*dri_library_name) (struct drm_device * dev, char * buf); /** @@ -783,12 +784,13 @@ typedef struct drm_device { /*@{ */ wait_queue_head_t vbl_queue; /**< VBLANK wait queue */ - atomic_t vbl_received; - atomic_t vbl_received2; /**< number of secondary VBLANK interrupts */ + atomic_t *vblank_count; /**< number of VBLANK interrupts (driver must alloc the right number of counters) */ spinlock_t vbl_lock; struct list_head vbl_sigs; /**< signal list to send on VBLANK */ struct list_head vbl_sigs2; /**< signals to send on secondary VBLANK */ - unsigned int vbl_pending; + atomic_t *vbl_pending; + u32 *last_vblank; /* protected by dev->vbl_lock */ + unsigned long max_vblank_count; /**< size of vblank counter register */ spinlock_t tasklet_lock; /**< For drm_locked_tasklet */ void (*locked_tasklet_func)(struct drm_device *dev); diff --git a/linux-core/drm_irq.c b/linux-core/drm_irq.c index 88716712..f229f778 100644 --- a/linux-core/drm_irq.c +++ b/linux-core/drm_irq.c @@ -221,6 +221,44 @@ int drm_control(struct inode *inode, struct file *filp, } } +static void drm_vblank_get(drm_device_t *dev, int crtc) +{ + unsigned long irqflags; + u32 cur_vblank, diff; + + if (atomic_add_return(1, &dev->vbl_pending[crtc]) != 1) + return; + + /* + * Interrupts were disabled prior to this call, so deal with counter + * wrap if needed. + * NOTE! It's possible we lost a full dev->max_vblank_count events + * here if the register is small or we had vblank interrupts off for + * a long time. + */ + cur_vblank = dev->driver->get_vblank_counter(dev, crtc); + spin_lock_irqsave(&dev->vbl_lock, irqflags); + if (cur_vblank < dev->last_vblank[crtc]) { + diff = dev->max_vblank_count - + dev->last_vblank[crtc]; + diff += cur_vblank; + } else { + diff = cur_vblank - last_vblank; + } + dev->last_vblank[crtc] = cur_vblank; + spin_lock_irqrestore(&dev->vbl_lock, irqflags); + + atomic_add(diff, &dev->vblank_count[crtc]); + dev->driver->enable_vblank(dev, crtc); +} + +static void drm_vblank_put(drm_device_t *dev, int crtc) +{ + if (atomic_dec_and_test(&dev->vbl_pending[crtc])) + dev->driver->disable_vblank(dev, crtc); +} + + /** * Wait for VBLANK. * @@ -248,7 +286,7 @@ int drm_wait_vblank(DRM_IOCTL_ARGS) drm_wait_vblank_t vblwait; struct timeval now; int ret = 0; - unsigned int flags, seq; + unsigned int flags, seq, crtc; if ((!dev->irq) || (!dev->irq_enabled)) return -EINVAL; @@ -265,13 +303,14 @@ int drm_wait_vblank(DRM_IOCTL_ARGS) } flags = vblwait.request.type & _DRM_VBLANK_FLAGS_MASK; + crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0; if (!drm_core_check_feature(dev, (flags & _DRM_VBLANK_SECONDARY) ? DRIVER_IRQ_VBL2 : DRIVER_IRQ_VBL)) return -EINVAL; - seq = atomic_read((flags & _DRM_VBLANK_SECONDARY) ? &dev->vbl_received2 - : &dev->vbl_received); + drm_vblank_get(dev, crtc); + seq = atomic_read(&dev->vblank_count[crtc]); switch (vblwait.request.type & _DRM_VBLANK_TYPES_MASK) { case _DRM_VBLANK_RELATIVE: @@ -307,22 +346,23 @@ int drm_wait_vblank(DRM_IOCTL_ARGS) spin_unlock_irqrestore(&dev->vbl_lock, irqflags); vblwait.reply.sequence = seq; + drm_vblank_put(dev, crtc); goto done; } } - if (dev->vbl_pending >= 100) { + if (atomic_read(&dev->vbl_pending[crtc]) >= 100) { spin_unlock_irqrestore(&dev->vbl_lock, irqflags); + drm_vblank_put(dev, crtc); return -EBUSY; } - dev->vbl_pending++; - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); if (! (vbl_sig = drm_alloc(sizeof(drm_vbl_sig_t), DRM_MEM_DRIVER))) { + drm_vblank_put(dev, crtc); return -ENOMEM; } @@ -340,14 +380,12 @@ int drm_wait_vblank(DRM_IOCTL_ARGS) vblwait.reply.sequence = seq; } else { - if (flags & _DRM_VBLANK_SECONDARY) { - if (dev->driver->vblank_wait2) - ret = dev->driver->vblank_wait2(dev, &vblwait.request.sequence); - } else if (dev->driver->vblank_wait) - ret = - dev->driver->vblank_wait(dev, - &vblwait.request.sequence); + unsigned long cur_vblank; + DRM_WAIT_ON(ret, dev->vbl_queue, 3 * DRM_HZ, + (((cur_vblank = atomic_read(&dev->vblank_count[crtc])) + - seq) <= (1 << 23))); + drm_vblank_put(dev, crtc); do_gettimeofday(&now); vblwait.reply.tval_sec = now.tv_sec; vblwait.reply.tval_usec = now.tv_usec; @@ -379,8 +417,7 @@ void drm_vbl_send_signals(drm_device_t * dev) for (i = 0; i < 2; i++) { drm_vbl_sig_t *vbl_sig, *tmp; struct list_head *vbl_sigs = i ? &dev->vbl_sigs2 : &dev->vbl_sigs; - unsigned int vbl_seq = atomic_read(i ? &dev->vbl_received2 : - &dev->vbl_received); + unsigned int vbl_seq = atomic_read(&dev->vblank_count[i]); list_for_each_entry_safe(vbl_sig, tmp, vbl_sigs, head) { if ((vbl_seq - vbl_sig->sequence) <= (1 << 23)) { @@ -393,7 +430,7 @@ void drm_vbl_send_signals(drm_device_t * dev) drm_free(vbl_sig, sizeof(*vbl_sig), DRM_MEM_DRIVER); - dev->vbl_pending--; + drm_vblank_put(dev, i); } } } diff --git a/linux-core/i915_drv.c b/linux-core/i915_drv.c index 7fdb0839..e7a9bfdc 100644 --- a/linux-core/i915_drv.c +++ b/linux-core/i915_drv.c @@ -83,8 +83,9 @@ static struct drm_driver driver = { .lastclose = i915_driver_lastclose, .preclose = i915_driver_preclose, .device_is_agp = i915_driver_device_is_agp, - .vblank_wait = i915_driver_vblank_wait, - .vblank_wait2 = i915_driver_vblank_wait2, + .get_vblank_counter = i915_get_vblank_counter, + .enable_vblank = i915_enable_vblank, + .disable_vblank = i915_disable_vblank, .irq_preinstall = i915_driver_irq_preinstall, .irq_postinstall = i915_driver_irq_postinstall, .irq_uninstall = i915_driver_irq_uninstall, -- cgit v1.2.3