Re: [PATCH 5/7] drm/sun4i: Add planes driver

["Jernej Škrabec" <jernej.skrabec@gmail.com>]

Dne četrtek, 25. december 2025 ob 10:37:06 Srednjeevropski standardni čas je Chen-Yu Tsai napisal(a):
> On Thu, Dec 25, 2025 at 5:29 PM Chen-Yu Tsai <wens@kernel.org> wrote:
> >
> > On Sat, Nov 15, 2025 at 10:14 PM Jernej Skrabec
> > <jernej.skrabec@gmail.com> wrote:
> > >
> > > This driver serves just as planes sharing manager, needed for Display
> > > Engine 3.3 and newer.
> > >
> > > Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
> > > ---
> > >  drivers/gpu/drm/sun4i/Kconfig         |   8 +
> > >  drivers/gpu/drm/sun4i/Makefile        |   1 +
> > >  drivers/gpu/drm/sun4i/sun50i_planes.c | 205 ++++++++++++++++++++++++++
> > >  drivers/gpu/drm/sun4i/sun50i_planes.h |  43 ++++++
> > >  4 files changed, 257 insertions(+)
> > >  create mode 100644 drivers/gpu/drm/sun4i/sun50i_planes.c
> > >  create mode 100644 drivers/gpu/drm/sun4i/sun50i_planes.h
> > >
> > > diff --git a/drivers/gpu/drm/sun4i/Kconfig b/drivers/gpu/drm/sun4i/Kconfig
> > > index b56ba00aabca..946dd7606094 100644
> > > --- a/drivers/gpu/drm/sun4i/Kconfig
> > > +++ b/drivers/gpu/drm/sun4i/Kconfig
> > > @@ -85,4 +85,12 @@ config DRM_SUN8I_TCON_TOP
> > >           TCON TOP is responsible for configuring display pipeline for
> > >           HDMI, TVE and LCD.
> > >
> > > +config DRM_SUN50I_PLANES
> > > +       tristate
> > > +       default DRM_SUN4I if DRM_SUN8I_MIXER!=n
> > > +       help
> > > +         Chose this option if you have an Allwinner Soc with the
> > > +         Display Engine 3.3 or newer. Planes are shared resource
> > > +         between multiple mixers.
> > > +
> > >  endif
> > > diff --git a/drivers/gpu/drm/sun4i/Makefile b/drivers/gpu/drm/sun4i/Makefile
> > > index bad7497a0d11..03f002abef15 100644
> > > --- a/drivers/gpu/drm/sun4i/Makefile
> > > +++ b/drivers/gpu/drm/sun4i/Makefile
> > > @@ -38,3 +38,4 @@ obj-$(CONFIG_DRM_SUN6I_DSI)   += sun6i_mipi_dsi.o
> > >  obj-$(CONFIG_DRM_SUN8I_DW_HDMI)        += sun8i-drm-hdmi.o
> > >  obj-$(CONFIG_DRM_SUN8I_MIXER)  += sun8i-mixer.o
> > >  obj-$(CONFIG_DRM_SUN8I_TCON_TOP) += sun8i_tcon_top.o
> > > +obj-$(CONFIG_DRM_SUN50I_PLANES)        += sun50i_planes.o
> >
> > I don't think you can have this as a separate module:
> >
> > a. You are using sun8i_vi_layer_init_one() and sun8i_ui_layer_init_one()
> >    from the sun8i-mixer module, and neither of them are exported symbols.
> >
> > b. You export sun50i_planes_setup() for sun8i-mixer to call, which ends
> >    up becoming a circular dependency.
> >
> > The easiest solution would be to just fold this into the sun8i-mixer module.

I mimicked tcon-top module, but yeah, it's much less of a hassle to fold it
into sun8i-mixer.

> >
> >
> > > diff --git a/drivers/gpu/drm/sun4i/sun50i_planes.c b/drivers/gpu/drm/sun4i/sun50i_planes.c
> > > new file mode 100644
> > > index 000000000000..a99c01122990
> > > --- /dev/null
> > > +++ b/drivers/gpu/drm/sun4i/sun50i_planes.c
> > > @@ -0,0 +1,205 @@
> > > +// SPDX-License-Identifier: GPL-2.0+
> > > +/* Copyright (c) 2025 Jernej Skrabec <jernej.skrabec@gmail.com> */
> > > +
> > > +#include <linux/device.h>
> > > +#include <linux/io.h>
> > > +#include <linux/mfd/syscon.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of.h>
> > > +#include <linux/of_graph.h>
> > > +#include <linux/platform_device.h>
> > > +
> > > +#include "sun50i_planes.h"
> > > +#include "sun8i_ui_layer.h"
> > > +#include "sun8i_vi_layer.h"
> > > +
> > > +static bool sun50i_planes_node_is_planes(struct device_node *node)
> > > +{
> > > +       return !!of_match_node(sun50i_planes_of_table, node);
> > > +}
> > > +
> > > +struct drm_plane **
> > > +sun50i_planes_setup(struct device *dev, struct drm_device *drm,
> > > +                   unsigned int mixer)
> > > +{
> > > +       struct sun50i_planes *planes = dev_get_drvdata(dev);
> > > +       const struct sun50i_planes_quirks *quirks;
> > > +       struct drm_plane **drm_planes;
> > > +       const struct default_map *map;
> > > +       unsigned int i;
> > > +
> > > +       if (!sun50i_planes_node_is_planes(dev->of_node)) {
> > > +               dev_err(dev, "Device is not planes driver!\n");
> > > +               return NULL;
> > > +       }
> > > +
> > > +       if (!planes) {
> > > +               dev_err(dev, "Planes driver is not loaded yet!\n");
> > > +               return NULL;
> > > +       }
> > > +
> > > +       if (mixer > 1) {
> > > +               dev_err(dev, "Mixer index is too high!\n");
> > > +               return NULL;
> > > +       }
> > > +
> > > +       quirks = planes->quirks;
> > > +       map = &quirks->def_map[mixer];
> > > +
> > > +       drm_planes = devm_kcalloc(drm->dev, map->num_ch + 1,
> >
> > Just a note: it seems we are missing the sentinel in sun8i_layers_init().

Why do you think so? Current mainline code has mixer->cfg->vi_num +
mixer->cfg->ui_num + 1.

> >
> > > +                                 sizeof(*drm_planes), GFP_KERNEL);
> > > +       if (!drm_planes)
> > > +               return ERR_PTR(-ENOMEM);
> > > +
> > > +       for (i = 0; i < map->num_ch; i++) {
> > > +               unsigned int phy_ch = map->map[i];
> > > +               struct sun8i_layer *layer;
> > > +               enum drm_plane_type type;
> > > +
> > > +               if ((i == 0 && map->num_ch == 1) || i == 1)
> > > +                       type = DRM_PLANE_TYPE_PRIMARY;
> > > +               else
> > > +                       type = DRM_PLANE_TYPE_OVERLAY;
> > > +
> > > +               if (phy_ch < UI_PLANE_OFFSET)
> > > +                       layer = sun8i_vi_layer_init_one(drm, type, planes->regs,
> > > +                                                       i, phy_ch, map->num_ch,
> > > +                                                       &quirks->cfg);
> > > +               else
> > > +                       layer = sun8i_ui_layer_init_one(drm, type, planes->regs,
> > > +                                                       i, phy_ch, map->num_ch,
> > > +                                                       &quirks->cfg);
> > > +
> > > +               if (IS_ERR(layer)) {
> > > +                       dev_err(drm->dev,
> > > +                               "Couldn't initialize DRM plane\n");
> > > +                       return ERR_CAST(layer);
> > > +               }
> > > +
> > > +               drm_planes[i] = &layer->plane;
> > > +       }
> > > +
> > > +       return drm_planes;
> > > +}
> > > +EXPORT_SYMBOL(sun50i_planes_setup);
> > > +
> > > +static void sun50i_planes_init_mapping(struct sun50i_planes *planes)
> > > +{
> > > +       const struct sun50i_planes_quirks *quirks = planes->quirks;
> > > +       unsigned int i, j;
> > > +       u32 mapping;
> > > +
> > > +       mapping = 0;
> > > +       for (j = 0; j < MAX_DISP; j++)
> > > +               for (i = 0; i < quirks->def_map[j].num_ch; i++) {
> > > +                       unsigned int ch = quirks->def_map[j].map[i];
> > > +
> > > +                       if (ch < UI_PLANE_OFFSET)
> > > +                               mapping |= j << (ch * 2);
> > > +                       else
> > > +                               mapping |= j << ((ch - UI_PLANE_OFFSET) * 2 + 16);
> > > +               }
> > > +       regmap_write(planes->mapping, SUNXI_DE33_DE_CHN2CORE_MUX_REG, mapping);
> > > +
> > > +       for (j = 0; j < MAX_DISP; j++) {
> > > +               mapping = 0;
> > > +               for (i = 0; i < quirks->def_map[j].num_ch; i++) {
> > > +                       unsigned int ch = quirks->def_map[j].map[i];
> > > +
> > > +                       if (ch >= UI_PLANE_OFFSET)
> > > +                               ch += 2;
> > > +
> > > +                       mapping |= ch << (i * 4);
> > > +               }
> > > +               regmap_write(planes->mapping, SUNXI_DE33_DE_PORT02CHN_MUX_REG + j * 4, mapping);
> > > +       }
> > > +}
> > > +
> > > +static const struct regmap_config sun50i_planes_regmap_config = {
> > > +       .name           = "planes",
> > > +       .reg_bits       = 32,
> > > +       .val_bits       = 32,
> > > +       .reg_stride     = 4,
> > > +       .max_register   = 0x17fffc,
> > > +};
> > > +
> > > +static int sun50i_planes_probe(struct platform_device *pdev)
> > > +{
> > > +       struct device *dev = &pdev->dev;
> > > +       struct sun50i_planes *planes;
> > > +       void __iomem *regs;
> > > +
> > > +       planes = devm_kzalloc(dev, sizeof(*planes), GFP_KERNEL);
> > > +       if (!planes)
> > > +               return -ENOMEM;
> > > +
> > > +       planes->quirks = of_device_get_match_data(&pdev->dev);
> > > +       if (!planes->quirks)
> > > +               return dev_err_probe(dev, -EINVAL, "Unable to get quirks\n");
> > > +
> > > +       planes->mapping = syscon_regmap_lookup_by_phandle(dev->of_node,
> > > +                                                         "allwinner,plane-mapping");
> > > +       if (IS_ERR(planes->mapping))
> > > +               return dev_err_probe(dev, PTR_ERR(planes->mapping),
> > > +                                    "Unable to get mapping\n");
> > > +
> > > +       regs = devm_platform_ioremap_resource(pdev, 0);
> > > +       if (IS_ERR(regs))
> > > +               return PTR_ERR(regs);
> > > +
> > > +       planes->regs = devm_regmap_init_mmio(dev, regs, &sun50i_planes_regmap_config);
> > > +       if (IS_ERR(planes->regs))
> > > +               return PTR_ERR(planes->regs);
> > > +
> > > +       dev_set_drvdata(dev, planes);
> > > +
> > > +       sun50i_planes_init_mapping(planes);
> > > +
> > > +       return 0;
> > > +}
> > > +
> > > +static const struct sun50i_planes_quirks sun50i_h616_planes_quirks = {
> > > +       .def_map = {
> > > +               {
> > > +                       .map = {0, 6, 7},
> > > +                       .num_ch = 3,
> > > +               },
> > > +               {
> > > +                       .map = {1, 2, 8},
> > > +                       .num_ch = 3,
> > > +               },
> > > +       },
> > > +       .cfg = {
> > > +               .de_type        = SUN8I_MIXER_DE33,
> > > +               /*
> > > +                * TODO: All planes support scaling, but driver needs
> > > +                * improvements to properly support it.
> > > +                */
> > > +               .scaler_mask    = 0,
> > > +               .scanline_yuv   = 4096,
> > > +       },
> > > +};
> > > +
> > > +/* sun4i_drv uses this list to check if a device node is a plane */
> 
> I didn't see any usage of this in patch 7. Is this part of another
> series?
> 
> Maybe just export sun50i_planes_node_is_planes() instead?

It's not needed if driver is folder into sun8i-mixer module. Looks like this
is remnant of tcon-top concept...

> 
> > > +const struct of_device_id sun50i_planes_of_table[] = {
> > > +       {
> > > +               .compatible = "allwinner,sun50i-h616-de33-planes",
> > > +               .data = &sun50i_h616_planes_quirks
> > > +       },
> > > +       { }
> > > +};
> > > +MODULE_DEVICE_TABLE(of, sun50i_planes_of_table);
> > > +EXPORT_SYMBOL(sun50i_planes_of_table);
> > > +
> > > +static struct platform_driver sun50i_planes_platform_driver = {
> > > +       .probe          = sun50i_planes_probe,
> > > +       .driver         = {
> > > +               .name           = "sun50i-planes",
> > > +               .of_match_table = sun50i_planes_of_table,
> > > +       },
> > > +};
> > > +module_platform_driver(sun50i_planes_platform_driver);
> > > +
> > > +MODULE_AUTHOR("Jernej Skrabec <jernej.skrabec@gmail.com>");
> > > +MODULE_DESCRIPTION("Allwinner DE33 planes driver");
> > > +MODULE_LICENSE("GPL");
> > > diff --git a/drivers/gpu/drm/sun4i/sun50i_planes.h b/drivers/gpu/drm/sun4i/sun50i_planes.h
> > > new file mode 100644
> > > index 000000000000..446feaeb03fc
> > > --- /dev/null
> > > +++ b/drivers/gpu/drm/sun4i/sun50i_planes.h
> > > @@ -0,0 +1,43 @@
> > > +/* SPDX-License-Identifier: GPL-2.0+ */
> > > +/* Copyright (c) 2025 Jernej Skrabec <jernej.skrabec@gmail.com> */
> > > +
> > > +#ifndef _SUN50I_PLANES_H_
> > > +#define _SUN50I_PLANES_H_
> > > +
> > > +#include <drm/drm_device.h>
> > > +#include <linux/regmap.h>
> >
> > I think you could move these two to the .c file, and just use forward
> > declarations here.

Ok.

Best regards,
Jernej

> >
> > The rest looks OK.
> >
> >
> > > +
> > > +#include "sun8i_mixer.h"
> > > +
> > > +/* mapping registers, located in clock register space */
> > > +#define SUNXI_DE33_DE_CHN2CORE_MUX_REG 0x24
> > > +#define SUNXI_DE33_DE_PORT02CHN_MUX_REG        0x28
> > > +#define SUNXI_DE33_DE_PORT12CHN_MUX_REG        0x2c
> > > +
> > > +#define MAX_DISP       2
> > > +#define MAX_CHANNELS   8
> > > +#define UI_PLANE_OFFSET        6
> > > +
> > > +struct default_map {
> > > +       unsigned int map[MAX_CHANNELS];
> > > +       unsigned int num_ch;
> > > +};
> > > +
> > > +struct sun50i_planes_quirks {
> > > +       struct default_map      def_map[MAX_DISP];
> > > +       struct sun8i_layer_cfg  cfg;
> > > +};
> > > +
> > > +struct sun50i_planes {
> > > +       struct regmap                           *regs;
> > > +       struct regmap                           *mapping;
> > > +       const struct sun50i_planes_quirks       *quirks;
> > > +};
> > > +
> > > +extern const struct of_device_id sun50i_planes_of_table[];
> > > +
> > > +struct drm_plane **
> > > +sun50i_planes_setup(struct device *dev, struct drm_device *drm,
> > > +                   unsigned int mixer);
> > > +
> > > +#endif /* _SUN50I_PLANES_H_ */
> > > --
> > > 2.51.2
> > >
> > >
>