On Wed, 22 Mar 2017, Daniel Vetter <daniel@xxxxxxxx> wrote:
> On Wed, Mar 22, 2017 at 12:33:35PM +0200, Jani Nikula wrote:
>> On Wed, 22 Mar 2017, Daniel Vetter <daniel.vetter@xxxxxxxx> wrote:
>> > There's really no reason for anything more:
>> > - Calling this while the crtc vblank stuff isn't set up is a driver
>> > bug. Those places arlready DRM_ERROR.
>> > - Calling this when the crtc is off is either a driver bug (callin
>> > drm_crtc_handle_vblank at the wrong time) or a core bug (for
>> > anything else). Again, we DRM_ERROR.
>> > - EINVAL is checked at higher levels already, and if we'd use struct
>> > drm_crtc * instead of (dev, pipe) it would be real obvious that
>> > those are again core bugs.
>> >
>> > The only valid failure mode is crap hardware that couldn't sample a
>> > useful timestamp, to ask the core to just grab a not-so-accurate
>> > timestampe. Bool is perfectly fine for that.
>>
>> FWIW, I'm not all that thrilled about changing int returns to bools,
>> because it changes the check for success from !ret to ret, and the
>> compiler won't help you. Sure, there aren't many call sites for the
>> function, but, case in point, you forgot to change that lone call
>> site. Though it still works by coincidence.
>
> The old call site treated > 0 as success, and 0 or anything negative as
> failure. That the lone caller still works is the reason why I've switched
> to bool, because besides all the funny values that the caller gets and
> ignreos, it already is.
>
> Or did I miss something?
Don't you think you should fix the call site too, if you insist on
changing the return type?
BR,
Jani.
> -Daniel
>
>>
>> BR,
>> Jani.
>>
>> >
>> > Cc: Mario Kleiner <mario.kleiner@xxxxxxxxxxxxxxxx>
>> > Cc: Eric Anholt <eric@xxxxxxxxxx>
>> > Cc: Rob Clark <robdclark@xxxxxxxxx>
>> > Cc: linux-arm-msm@xxxxxxxxxxxxxxx
>> > Cc: freedreno@xxxxxxxxxxxxxxxxxxxxx
>> > Cc: Alex Deucher <alexander.deucher@xxxxxxx>
>> > Cc: Christian König <christian.koenig@xxxxxxx>
>> > Cc: Ben Skeggs <bskeggs@xxxxxxxxxx>
>> > Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx>
>> > ---
>> > drivers/gpu/drm/amd/amdgpu/amdgpu.h | 8 +++----
>> > drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 14 ++++++------
>> > drivers/gpu/drm/drm_irq.c | 37 +++++++++++--------------------
>> > drivers/gpu/drm/i915/i915_irq.c | 8 +++----
>> > drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c | 12 +++++-----
>> > drivers/gpu/drm/nouveau/nouveau_display.c | 4 ++--
>> > drivers/gpu/drm/nouveau/nouveau_display.h | 4 ++--
>> > drivers/gpu/drm/radeon/radeon_drv.c | 8 +++----
>> > drivers/gpu/drm/radeon/radeon_kms.c | 14 ++++++------
>> > drivers/gpu/drm/vc4/vc4_crtc.c | 2 +-
>> > drivers/gpu/drm/vc4/vc4_drv.h | 2 +-
>> > include/drm/drmP.h | 1 -
>> > include/drm/drm_drv.h | 7 +++---
>> > include/drm/drm_irq.h | 10 ++++-----
>> > 14 files changed, 59 insertions(+), 72 deletions(-)
>> >
>> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> > index c8860f05bfb9..acd8631d8024 100644
>> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> > @@ -1768,10 +1768,10 @@ int amdgpu_device_resume(struct drm_device *dev, bool resume, bool fbcon);
>> > u32 amdgpu_get_vblank_counter_kms(struct drm_device *dev, unsigned int pipe);
>> > int amdgpu_enable_vblank_kms(struct drm_device *dev, unsigned int pipe);
>> > void amdgpu_disable_vblank_kms(struct drm_device *dev, unsigned int pipe);
>> > -int amdgpu_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
>> > - int *max_error,
>> > - struct timeval *vblank_time,
>> > - unsigned flags);
>> > +bool amdgpu_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
>> > + int *max_error,
>> > + struct timeval *vblank_time,
>> > + unsigned flags);
>> > long amdgpu_kms_compat_ioctl(struct file *filp, unsigned int cmd,
>> > unsigned long arg);
>> >
>> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>> > index 55f951bcc91f..ac42f707c046 100644
>> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>> > @@ -838,19 +838,19 @@ void amdgpu_disable_vblank_kms(struct drm_device *dev, unsigned int pipe)
>> > *
>> > * Gets the timestamp on the requested crtc based on the
>> > * scanout position. (all asics).
>> > - * Returns postive status flags on success, negative error on failure.
>> > + * Returns true on success, false on failure.
>> > */
>> > -int amdgpu_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
>> > - int *max_error,
>> > - struct timeval *vblank_time,
>> > - unsigned flags)
>> > +bool amdgpu_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
>> > + int *max_error,
>> > + struct timeval *vblank_time,
>> > + unsigned flags)
>> > {
>> > struct drm_crtc *crtc;
>> > struct amdgpu_device *adev = dev->dev_private;
>> >
>> > if (pipe >= dev->num_crtcs) {
>> > DRM_ERROR("Invalid crtc %u\n", pipe);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > /* Get associated drm_crtc: */
>> > @@ -859,7 +859,7 @@ int amdgpu_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
>> > /* This can occur on driver load if some component fails to
>> > * initialize completely and driver is unloaded */
>> > DRM_ERROR("Uninitialized crtc %d\n", pipe);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > /* Helper routine in DRM core does all the work: */
>> > diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
>> > index 4b0c7475ed13..2121ea29e1b2 100644
>> > --- a/drivers/gpu/drm/drm_irq.c
>> > +++ b/drivers/gpu/drm/drm_irq.c
>> > @@ -722,43 +722,32 @@ EXPORT_SYMBOL(drm_calc_timestamping_constants);
>> > * active. Higher level code is expected to handle this.
>> > *
>> > * Returns:
>> > - * Negative value on error, failure or if not supported in current
>> > - * video mode:
>> > - *
>> > - * -EINVAL Invalid CRTC.
>> > - * -EAGAIN Temporary unavailable, e.g., called before initial modeset.
>> > - * -ENOTSUPP Function not supported in current display mode.
>> > - * -EIO Failed, e.g., due to failed scanout position query.
>> > - *
>> > - * Returns or'ed positive status flags on success:
>> > - *
>> > - * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
>> > - * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
>> > *
>> > + * Returns true on success, and false on failure, i.e. when no accurate
>> > + * timestamp could be acquired.
>> > */
>> > -int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
>> > - unsigned int pipe,
>> > - int *max_error,
>> > - struct timeval *vblank_time,
>> > - unsigned flags,
>> > - const struct drm_display_mode *mode)
>> > +bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
>> > + unsigned int pipe,
>> > + int *max_error,
>> > + struct timeval *vblank_time,
>> > + unsigned flags,
>> > + const struct drm_display_mode *mode)
>> > {
>> > struct timeval tv_etime;
>> > ktime_t stime, etime;
>> > unsigned int vbl_status;
>> > - int ret = DRM_VBLANKTIME_SCANOUTPOS_METHOD;
>> > int vpos, hpos, i;
>> > int delta_ns, duration_ns;
>> >
>> > if (pipe >= dev->num_crtcs) {
>> > DRM_ERROR("Invalid crtc %u\n", pipe);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > /* Scanout position query not supported? Should not happen. */
>> > if (!dev->driver->get_scanout_position) {
>> > DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
>> > - return -EIO;
>> > + return false;
>> > }
>> >
>> > /* If mode timing undefined, just return as no-op:
>> > @@ -766,7 +755,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
>> > */
>> > if (mode->crtc_clock == 0) {
>> > DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe);
>> > - return -EAGAIN;
>> > + return false;
>> > }
>> >
>> > /* Get current scanout position with system timestamp.
>> > @@ -790,7 +779,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
>> > if (!(vbl_status & DRM_SCANOUTPOS_VALID)) {
>> > DRM_DEBUG("crtc %u : scanoutpos query failed [0x%x].\n",
>> > pipe, vbl_status);
>> > - return -EIO;
>> > + return false;
>> > }
>> >
>> > /* Compute uncertainty in timestamp of scanout position query. */
>> > @@ -834,7 +823,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
>> > (long)vblank_time->tv_sec, (long)vblank_time->tv_usec,
>> > duration_ns/1000, i);
>> >
>> > - return ret;
>> > + return true;
>> > }
>> > EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
>> >
>> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
>> > index 26aa1c170b43..df149d159ce7 100644
>> > --- a/drivers/gpu/drm/i915/i915_irq.c
>> > +++ b/drivers/gpu/drm/i915/i915_irq.c
>> > @@ -964,7 +964,7 @@ int intel_get_crtc_scanline(struct intel_crtc *crtc)
>> > return position;
>> > }
>> >
>> > -static int i915_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
>> > +static bool i915_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
>> > int *max_error,
>> > struct timeval *vblank_time,
>> > unsigned flags)
>> > @@ -974,19 +974,19 @@ static int i915_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
>> >
>> > if (pipe >= INTEL_INFO(dev_priv)->num_pipes) {
>> > DRM_ERROR("Invalid crtc %u\n", pipe);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > /* Get drm_crtc to timestamp: */
>> > crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
>> > if (crtc == NULL) {
>> > DRM_ERROR("Invalid crtc %u\n", pipe);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > if (!crtc->base.hwmode.crtc_clock) {
>> > DRM_DEBUG_KMS("crtc %u is disabled\n", pipe);
>> > - return -EBUSY;
>> > + return false;
>> > }
>> >
>> > /* Helper routine in DRM core does all the work: */
>> > diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
>> > index 41ccd2a15d3c..655700eb42ba 100644
>> > --- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
>> > +++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
>> > @@ -595,23 +595,23 @@ static int mdp5_get_scanoutpos(struct drm_device *dev, unsigned int pipe,
>> > return ret;
>> > }
>> >
>> > -static int mdp5_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
>> > - int *max_error,
>> > - struct timeval *vblank_time,
>> > - unsigned flags)
>> > +static bool mdp5_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
>> > + int *max_error,
>> > + struct timeval *vblank_time,
>> > + unsigned flags)
>> > {
>> > struct msm_drm_private *priv = dev->dev_private;
>> > struct drm_crtc *crtc;
>> >
>> > if (pipe < 0 || pipe >= priv->num_crtcs) {
>> > DRM_ERROR("Invalid crtc %d\n", pipe);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > crtc = priv->crtcs[pipe];
>> > if (!crtc) {
>> > DRM_ERROR("Invalid crtc %d\n", pipe);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > return drm_calc_vbltimestamp_from_scanoutpos(dev, pipe, max_error,
>> > diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
>> > index 33269c7df30f..42f18b0b9c43 100644
>> > --- a/drivers/gpu/drm/nouveau/nouveau_display.c
>> > +++ b/drivers/gpu/drm/nouveau/nouveau_display.c
>> > @@ -156,7 +156,7 @@ nouveau_display_scanoutpos(struct drm_device *dev, unsigned int pipe,
>> > return 0;
>> > }
>> >
>> > -int
>> > +bool
>> > nouveau_display_vblstamp(struct drm_device *dev, unsigned int pipe,
>> > int *max_error, struct timeval *time, unsigned flags)
>> > {
>> > @@ -174,7 +174,7 @@ nouveau_display_vblstamp(struct drm_device *dev, unsigned int pipe,
>> > }
>> > }
>> >
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > static void
>> > diff --git a/drivers/gpu/drm/nouveau/nouveau_display.h b/drivers/gpu/drm/nouveau/nouveau_display.h
>> > index 4a75df06c139..bc9d1e7b0117 100644
>> > --- a/drivers/gpu/drm/nouveau/nouveau_display.h
>> > +++ b/drivers/gpu/drm/nouveau/nouveau_display.h
>> > @@ -71,8 +71,8 @@ void nouveau_display_vblank_disable(struct drm_device *, unsigned int);
>> > int nouveau_display_scanoutpos(struct drm_device *, unsigned int,
>> > unsigned int, int *, int *, ktime_t *,
>> > ktime_t *, const struct drm_display_mode *);
>> > -int nouveau_display_vblstamp(struct drm_device *, unsigned int, int *,
>> > - struct timeval *, unsigned);
>> > +bool nouveau_display_vblstamp(struct drm_device *, unsigned int, int *,
>> > + struct timeval *, unsigned);
>> >
>> > int nouveau_crtc_page_flip(struct drm_crtc *crtc, struct drm_framebuffer *fb,
>> > struct drm_pending_vblank_event *event,
>> > diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
>> > index 312436a8d9e5..6d79b5c2805b 100644
>> > --- a/drivers/gpu/drm/radeon/radeon_drv.c
>> > +++ b/drivers/gpu/drm/radeon/radeon_drv.c
>> > @@ -114,10 +114,10 @@ int radeon_resume_kms(struct drm_device *dev, bool resume, bool fbcon);
>> > u32 radeon_get_vblank_counter_kms(struct drm_device *dev, unsigned int pipe);
>> > int radeon_enable_vblank_kms(struct drm_device *dev, unsigned int pipe);
>> > void radeon_disable_vblank_kms(struct drm_device *dev, unsigned int pipe);
>> > -int radeon_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
>> > - int *max_error,
>> > - struct timeval *vblank_time,
>> > - unsigned flags);
>> > +bool radeon_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
>> > + int *max_error,
>> > + struct timeval *vblank_time,
>> > + unsigned flags);
>> > void radeon_driver_irq_preinstall_kms(struct drm_device *dev);
>> > int radeon_driver_irq_postinstall_kms(struct drm_device *dev);
>> > void radeon_driver_irq_uninstall_kms(struct drm_device *dev);
>> > diff --git a/drivers/gpu/drm/radeon/radeon_kms.c b/drivers/gpu/drm/radeon/radeon_kms.c
>> > index a32a62e03a44..9afe72010c64 100644
>> > --- a/drivers/gpu/drm/radeon/radeon_kms.c
>> > +++ b/drivers/gpu/drm/radeon/radeon_kms.c
>> > @@ -868,25 +868,25 @@ void radeon_disable_vblank_kms(struct drm_device *dev, int crtc)
>> > *
>> > * Gets the timestamp on the requested crtc based on the
>> > * scanout position. (all asics).
>> > - * Returns postive status flags on success, negative error on failure.
>> > + * Returns true on success, false on failure.
>> > */
>> > -int radeon_get_vblank_timestamp_kms(struct drm_device *dev, int crtc,
>> > - int *max_error,
>> > - struct timeval *vblank_time,
>> > - unsigned flags)
>> > +bool radeon_get_vblank_timestamp_kms(struct drm_device *dev, int crtc,
>> > + int *max_error,
>> > + struct timeval *vblank_time,
>> > + unsigned flags)
>> > {
>> > struct drm_crtc *drmcrtc;
>> > struct radeon_device *rdev = dev->dev_private;
>> >
>> > if (crtc < 0 || crtc >= dev->num_crtcs) {
>> > DRM_ERROR("Invalid crtc %d\n", crtc);
>> > - return -EINVAL;
>> > + return false;
>> > }
>> >
>> > /* Get associated drm_crtc: */
>> > drmcrtc = &rdev->mode_info.crtcs[crtc]->base;
>> > if (!drmcrtc)
>> > - return -EINVAL;
>> > + return false;
>> >
>> > /* Helper routine in DRM core does all the work: */
>> > return drm_calc_vbltimestamp_from_scanoutpos(dev, crtc, max_error,
>> > diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
>> > index 24edd0c22cc9..74260990b6bf 100644
>> > --- a/drivers/gpu/drm/vc4/vc4_crtc.c
>> > +++ b/drivers/gpu/drm/vc4/vc4_crtc.c
>> > @@ -270,7 +270,7 @@ int vc4_crtc_get_scanoutpos(struct drm_device *dev, unsigned int crtc_id,
>> > return ret;
>> > }
>> >
>> > -int vc4_crtc_get_vblank_timestamp(struct drm_device *dev, unsigned int crtc_id,
>> > +bool vc4_crtc_get_vblank_timestamp(struct drm_device *dev, unsigned int crtc_id,
>> > int *max_error, struct timeval *vblank_time,
>> > unsigned flags)
>> > {
>> > diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h
>> > index dffce6293d87..8a5d0e12ee02 100644
>> > --- a/drivers/gpu/drm/vc4/vc4_drv.h
>> > +++ b/drivers/gpu/drm/vc4/vc4_drv.h
>> > @@ -450,7 +450,7 @@ int vc4_crtc_get_scanoutpos(struct drm_device *dev, unsigned int crtc_id,
>> > unsigned int flags, int *vpos, int *hpos,
>> > ktime_t *stime, ktime_t *etime,
>> > const struct drm_display_mode *mode);
>> > -int vc4_crtc_get_vblank_timestamp(struct drm_device *dev, unsigned int crtc_id,
>> > +bool vc4_crtc_get_vblank_timestamp(struct drm_device *dev, unsigned int crtc_id,
>> > int *max_error, struct timeval *vblank_time,
>> > unsigned flags);
>> >
>> > diff --git a/include/drm/drmP.h b/include/drm/drmP.h
>> > index 27ecfcdbf752..6304de7e041e 100644
>> > --- a/include/drm/drmP.h
>> > +++ b/include/drm/drmP.h
>> > @@ -322,7 +322,6 @@ struct pci_controller;
>> >
>> > /* Flags and return codes for get_vblank_timestamp() driver function. */
>> > #define DRM_CALLED_FROM_VBLIRQ 1
>> > -#define DRM_VBLANKTIME_SCANOUTPOS_METHOD (1 << 0)
>> >
>> > /* get_scanout_position() return flags */
>> > #define DRM_SCANOUTPOS_VALID (1 << 0)
>> > diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
>> > index d0b5f363bfa1..da78e248d9d8 100644
>> > --- a/include/drm/drm_drv.h
>> > +++ b/include/drm/drm_drv.h
>> > @@ -316,11 +316,10 @@ struct drm_driver {
>> > *
>> > * Returns:
>> > *
>> > - * Zero if timestamping isn't supported in current display mode or a
>> > - * negative number on failure. A positive status code on success,
>> > - * which describes how the vblank_time timestamp was computed.
>> > + * True on success, false on failure, which means the core should
>> > + * fallback to a simple timestamp taken in drm_crtc_handle_vblank().
>> > */
>> > - int (*get_vblank_timestamp) (struct drm_device *dev, unsigned int pipe,
>> > + bool (*get_vblank_timestamp) (struct drm_device *dev, unsigned int pipe,
>> > int *max_error,
>> > struct timeval *vblank_time,
>> > unsigned flags);
>> > diff --git a/include/drm/drm_irq.h b/include/drm/drm_irq.h
>> > index cf0be6594c8c..f0d5ccf9b282 100644
>> > --- a/include/drm/drm_irq.h
>> > +++ b/include/drm/drm_irq.h
>> > @@ -153,11 +153,11 @@ void drm_crtc_vblank_on(struct drm_crtc *crtc);
>> > void drm_vblank_cleanup(struct drm_device *dev);
>> > u32 drm_accurate_vblank_count(struct drm_crtc *crtc);
>> >
>> > -int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
>> > - unsigned int pipe, int *max_error,
>> > - struct timeval *vblank_time,
>> > - unsigned flags,
>> > - const struct drm_display_mode *mode);
>> > +bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
>> > + unsigned int pipe, int *max_error,
>> > + struct timeval *vblank_time,
>> > + unsigned flags,
>> > + const struct drm_display_mode *mode);
>> > void drm_calc_timestamping_constants(struct drm_crtc *crtc,
>> > const struct drm_display_mode *mode);
>>
>> --
>> Jani Nikula, Intel Open Source Technology Center
--
Jani Nikula, Intel Open Source Technology Center
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