Re: [PATCH 1/5] [media] rockchip/rga: v4l2 m2m support

[Randy Li]

On 06/27/2017 11:49 PM, Nicolas Dufresne wrote:
> Le mardi 27 juin 2017 Ã 23:11 +0800, Jacob Chen a Ãcrit :
> > Hi Nicolas.
> >
> > 2017-06-26 23:49 GMT+08:00 Nicolas Dufresne <nicolas@xxxxxxxxxxxx>:
> > > Le lundi 26 juin 2017 Ã 22:51 +0800, Jacob Chen a Ãcrit :
> > > > Rockchip RGA is a separate 2D raster graphic acceleration unit.
> > > > It
> > > > accelerates 2D graphics operations, such as point/line drawing,
> > > > image
> > > > scaling, rotation, BitBLT, alpha blending and image
> > > > blur/sharpness.
> > > >
> > > > The drvier is mostly based on s5p-g2d v4l2 m2m driver.
> > > > And supports various operations from the rendering pipeline.
> > > >   - copy
> > > >   - fast solid color fill
> > > >   - rotation
> > > >   - flip
> > > >   - alpha blending
> > > >
> > > > The code in rga-hw.c is used to configure regs accroding to
> > > > operations.
> > > >
> > > > The code in rga-buf.c is used to create private mmu table for
> > > > RGA.
> > > > The tables is stored in a list, and be removed when buffer is
> > > > cleanup.
> > > >
> > > > Signed-off-by: Jacob Chen <jacob-chen@xxxxxxxxxx>
> > > > ---
> > > >   drivers/media/platform/Kconfig                |  11 +
> > > >   drivers/media/platform/Makefile               |   2 +
> > > >   drivers/media/platform/rockchip-rga/Makefile  |   3 +
> > > >   drivers/media/platform/rockchip-rga/rga-buf.c | 176 +++++
> > > >   drivers/media/platform/rockchip-rga/rga-hw.c  | 456 ++++++++++++
> > > >   drivers/media/platform/rockchip-rga/rga-hw.h  | 434 ++++++++++++
> > > >   drivers/media/platform/rockchip-rga/rga.c     | 979
> > > > ++++++++++++++++++++++++++
> > > >   drivers/media/platform/rockchip-rga/rga.h     | 133 ++++
> > > >   8 files changed, 2194 insertions(+)
> > > >   create mode 100644 drivers/media/platform/rockchip-rga/Makefile
> > > >   create mode 100644 drivers/media/platform/rockchip-rga/rga-buf.c
> > > >   create mode 100644 drivers/media/platform/rockchip-rga/rga-hw.c
> > > >   create mode 100644 drivers/media/platform/rockchip-rga/rga-hw.h
> > > >   create mode 100644 drivers/media/platform/rockchip-rga/rga.c
> > > >   create mode 100644 drivers/media/platform/rockchip-rga/rga.h
> > >
> > > Could be nice to generalize. We could setup a control and fill the
> > > values base on porter duff operations, then drivers can implement a
> > > subset. Right now, there is no generic way for userspace to know if
> > > a
> > > driver is just doing copies with some transformations, or if it can
> > > actually do alpha blending hence used for composting streams. Note
> > > that
> > > I haven't looked at all possibilities, Freescale IMX.6 seems to
> > > have a
> > > similar driver, which has been wrapped in GStreamer with this
> > > proposed
> > > elements:
> > >
> > > https://bugzilla.gnome.org/show_bug.cgi?id=772766
> >
> > Yeah, i also want it use a generic api.
> > "porter duff operations" looks good, i will look at it.
> >
> > > > +#define V4L2_CID_RGA_ALHPA_REG0 (V4L2_CID_USER_BASE | 0x1002)
> > > > +#define V4L2_CID_RGA_ALHPA_REG1 (V4L2_CID_USER_BASE | 0x1003)
> > >
> > > It's not obvious why there is two CID, and how this differ from
> > > existing V4L2_CID_ALPHA (the global alpha control).
> >
> > They are used to calculate factors for below formulas.
> >
> >      dst alpha = Factor1 * src alpha + Factor2 * dst alpha
> >      dst color = Factor3 * src color + Factor4 * dst color
> >
> > I have no idea how to generalize it, and there is no upstream
> > application need it,
> > so i just simply exposed the reg.
In my memory, it is is used for convert AYUV to ARGB.
> Then maybe it's better to just not expose it in the public API in the
> initial patch (nothing forces you to enable everything). The idea is
> that it can be added later as needed, taking the time to figure-out a
> new API or to figure-out how this matches anything that exist.
>
> > > > +
> > > > +/* Operation values */
> > > > +#define OP_COPY 0
> > > > +#define OP_SOLID_FILL 1
> > > > +#define OP_ALPHA_BLEND 2
> > > > +
> > > > +struct rga_frame *rga_get_frame(struct rga_ctx *ctx, enum
> > > > v4l2_buf_type type);
> > > > +
> > > > +/* RGA Buffers Manage Part */
> > > > +extern const struct vb2_ops rga_qops;
> > > > +void *rga_buf_find_page(struct vb2_buffer *vb);
> > > > +void rga_buf_clean(struct rga_ctx *ctx);
> > > > +
> > > > +/* RGA Hardware Part */
> > > > +void rga_write(struct rockchip_rga *rga, u32 reg, u32 value);
> > > > +u32 rga_read(struct rockchip_rga *rga, u32 reg);
> > > > +void rga_mod(struct rockchip_rga *rga, u32 reg, u32 val, u32
> > > > mask);
> > > > +void rga_start(struct rockchip_rga *rga);
> > > > +void rga_cmd_set(struct rga_ctx *ctx, void *src_mmu_pages, void
> > > > *dst_mmu_pages);
> > > > +
> > > > +#endif

--
Randy Li