| Message ID | 1381319650-9799-3-git-send-email-amerilainen@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Oct 09, 2013 at 02:54:09PM +0300, Arto Merilainen wrote: > This patch makes the necessary additions to deliver syncpoint base > to the user space. > > This patch splits the index field in the drm_tegra_get_syncpt structure > into three separate fields (index, support_base, base_id). This allows > to keep compatibility over kernel versions: > - The placing of index field stays constant and therefore the interface > should stay compatible with earlier userspace versions. > - The old index field was input-only and it was not supposed to be read > afterwards. Delivering data back in the same field should not introduce > regressions to any old user space applications. > - Old kernels left support_base and base_id fields intact (zero) and > hence the new user space applications get the correct response from > the kernel (=syncpoint does not have a base). > > Signed-off-by: Arto Merilainen <amerilainen@nvidia.com> > --- > drivers/gpu/host1x/drm/drm.c | 2 ++ > include/uapi/drm/tegra_drm.h | 4 +++- > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/host1x/drm/drm.c b/drivers/gpu/host1x/drm/drm.c > index 8c61cee..4251563 100644 > --- a/drivers/gpu/host1x/drm/drm.c > +++ b/drivers/gpu/host1x/drm/drm.c > @@ -468,6 +468,8 @@ static int tegra_get_syncpt(struct drm_device *drm, void *data, > > syncpt = context->client->syncpts[args->index]; > args->id = host1x_syncpt_id(syncpt); > + args->support_base = syncpt->base ? 1 : 0; > + args->base_id = syncpt->base ? syncpt->base->id : 0; > > return 0; > } > diff --git a/include/uapi/drm/tegra_drm.h b/include/uapi/drm/tegra_drm.h > index 73bde4e..7a79ca5 100644 > --- a/include/uapi/drm/tegra_drm.h > +++ b/include/uapi/drm/tegra_drm.h > @@ -61,7 +61,9 @@ struct drm_tegra_close_channel { > > struct drm_tegra_get_syncpt { > __u64 context; > - __u32 index; > + __u16 index; > + __u8 support_base; > + __u8 base_id; > __u32 id; I don't like this. Can't we just add a separate IOCTL? Something like: struct drm_tegra_get_syncpt_base { __u64 context; __u32 syncpt; __u32 base; }; Which could be used somewhat like this: struct drm_tegra_get_syncpt_base args; memset(&args, 0, sizeof(args)); args.context = context; args.syncpt = syncpt; err = ioctl(fd, DRM_IOCTL_TEGRA_GET_SYNCPT_BASE, &args); if (err < 0) { /* * perhaps errno == ENOTSUP if the syncpoint has no * associated base? */ } base = args.base; Thierry
On 10/11/2013 12:43 PM, Thierry Reding wrote: > * PGP Signed by an unknown key > > On Wed, Oct 09, 2013 at 02:54:09PM +0300, Arto Merilainen wrote: >> This patch makes the necessary additions to deliver syncpoint base >> to the user space. >> >> This patch splits the index field in the drm_tegra_get_syncpt structure >> into three separate fields (index, support_base, base_id). This allows >> to keep compatibility over kernel versions: >> - The placing of index field stays constant and therefore the interface >> should stay compatible with earlier userspace versions. >> - The old index field was input-only and it was not supposed to be read >> afterwards. Delivering data back in the same field should not introduce >> regressions to any old user space applications. >> - Old kernels left support_base and base_id fields intact (zero) and >> hence the new user space applications get the correct response from >> the kernel (=syncpoint does not have a base). >> >> Signed-off-by: Arto Merilainen <amerilainen@nvidia.com> >> --- >> drivers/gpu/host1x/drm/drm.c | 2 ++ >> include/uapi/drm/tegra_drm.h | 4 +++- >> 2 files changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/host1x/drm/drm.c b/drivers/gpu/host1x/drm/drm.c >> index 8c61cee..4251563 100644 >> --- a/drivers/gpu/host1x/drm/drm.c >> +++ b/drivers/gpu/host1x/drm/drm.c >> @@ -468,6 +468,8 @@ static int tegra_get_syncpt(struct drm_device *drm, void *data, >> >> syncpt = context->client->syncpts[args->index]; >> args->id = host1x_syncpt_id(syncpt); >> + args->support_base = syncpt->base ? 1 : 0; >> + args->base_id = syncpt->base ? syncpt->base->id : 0; >> >> return 0; >> } >> diff --git a/include/uapi/drm/tegra_drm.h b/include/uapi/drm/tegra_drm.h >> index 73bde4e..7a79ca5 100644 >> --- a/include/uapi/drm/tegra_drm.h >> +++ b/include/uapi/drm/tegra_drm.h >> @@ -61,7 +61,9 @@ struct drm_tegra_close_channel { >> >> struct drm_tegra_get_syncpt { >> __u64 context; >> - __u32 index; >> + __u16 index; >> + __u8 support_base; >> + __u8 base_id; >> __u32 id; > > I don't like this. Can't we just add a separate IOCTL? Something like: Sure. This felt like a good idea, but I must admit I had a bit mixed feelings after looking my own explanation why this would be ok... - Arto
diff --git a/drivers/gpu/host1x/drm/drm.c b/drivers/gpu/host1x/drm/drm.c index 8c61cee..4251563 100644 --- a/drivers/gpu/host1x/drm/drm.c +++ b/drivers/gpu/host1x/drm/drm.c @@ -468,6 +468,8 @@ static int tegra_get_syncpt(struct drm_device *drm, void *data, syncpt = context->client->syncpts[args->index]; args->id = host1x_syncpt_id(syncpt); + args->support_base = syncpt->base ? 1 : 0; + args->base_id = syncpt->base ? syncpt->base->id : 0; return 0; } diff --git a/include/uapi/drm/tegra_drm.h b/include/uapi/drm/tegra_drm.h index 73bde4e..7a79ca5 100644 --- a/include/uapi/drm/tegra_drm.h +++ b/include/uapi/drm/tegra_drm.h @@ -61,7 +61,9 @@ struct drm_tegra_close_channel { struct drm_tegra_get_syncpt { __u64 context; - __u32 index; + __u16 index; + __u8 support_base; + __u8 base_id; __u32 id; };
This patch makes the necessary additions to deliver syncpoint base to the user space. This patch splits the index field in the drm_tegra_get_syncpt structure into three separate fields (index, support_base, base_id). This allows to keep compatibility over kernel versions: - The placing of index field stays constant and therefore the interface should stay compatible with earlier userspace versions. - The old index field was input-only and it was not supposed to be read afterwards. Delivering data back in the same field should not introduce regressions to any old user space applications. - Old kernels left support_base and base_id fields intact (zero) and hence the new user space applications get the correct response from the kernel (=syncpoint does not have a base). Signed-off-by: Arto Merilainen <amerilainen@nvidia.com> --- drivers/gpu/host1x/drm/drm.c | 2 ++ include/uapi/drm/tegra_drm.h | 4 +++- 2 files changed, 5 insertions(+), 1 deletion(-)