Re: [PATCH v2 07/12] drm/sun4i: Add a driver for the display frontend

From: Chen-Yu Tsai
Date: Thu Jan 04 2018 - 10:35:52 EST

On Mon, Dec 18, 2017 at 10:57 PM, Maxime Ripard
<maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote:
> The display frontend is an hardware block that can be used to implement
> some more advanced features like hardware scaling or colorspace
> conversions. It can also be used to implement the output format of the VPU.
>
> Let's create a minimal driver for it that will only enable the hardware
> scaling features.
>
> Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/sun4i/Makefile | 3 +-
> drivers/gpu/drm/sun4i/sun4i_drv.c | 16 +-
> drivers/gpu/drm/sun4i/sun4i_drv.h | 1 +-
> drivers/gpu/drm/sun4i/sun4i_frontend.c | 392 ++++++++++++++++++++++++++-
> drivers/gpu/drm/sun4i/sun4i_frontend.h | 96 ++++++-
> 5 files changed, 503 insertions(+), 5 deletions(-)
> create mode 100644 drivers/gpu/drm/sun4i/sun4i_frontend.c
> create mode 100644 drivers/gpu/drm/sun4i/sun4i_frontend.h
>
> diff --git a/drivers/gpu/drm/sun4i/Makefile b/drivers/gpu/drm/sun4i/Makefile
> index 0c2f8c7facae..b660d82011f4 100644
> --- a/drivers/gpu/drm/sun4i/Makefile
> +++ b/drivers/gpu/drm/sun4i/Makefile
> @@ -1,5 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
> sun4i-backend-y += sun4i_backend.o sun4i_layer.o
> +sun4i-frontend-y += sun4i_frontend.o
>
> sun4i-drm-y += sun4i_drv.o
> sun4i-drm-y += sun4i_framebuffer.o
> @@ -21,6 +22,6 @@ obj-$(CONFIG_DRM_SUN4I) += sun4i-tcon.o
> obj-$(CONFIG_DRM_SUN4I) += sun4i_tv.o
> obj-$(CONFIG_DRM_SUN4I) += sun6i_drc.o
>
> -obj-$(CONFIG_DRM_SUN4I_BACKEND) += sun4i-backend.o
> +obj-$(CONFIG_DRM_SUN4I_BACKEND) += sun4i-backend.o sun4i-frontend.o
> obj-$(CONFIG_DRM_SUN4I_HDMI) += sun4i-drm-hdmi.o
> obj-$(CONFIG_DRM_SUN8I_MIXER) += sun8i-mixer.o
> diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.c b/drivers/gpu/drm/sun4i/sun4i_drv.c
> index 75c76cdd82bc..17bf9bfd98ba 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_drv.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_drv.c
> @@ -98,6 +98,7 @@ static int sun4i_drv_bind(struct device *dev)
> goto free_drm;
> }
> drm->dev_private = drv;
> + INIT_LIST_HEAD(&drv->frontend_list);
> INIT_LIST_HEAD(&drv->engine_list);
> INIT_LIST_HEAD(&drv->tcon_list);
>
> @@ -239,9 +240,11 @@ static int sun4i_drv_add_endpoints(struct device *dev,
> int count = 0;
>
> /*
> - * We don't support the frontend for now, so we will never
> - * have a device bound. Just skip over it, but we still want
> - * the rest our pipeline to be added.
> + * The frontend has been disabled in all of our old device

Not quite... I left them enabled in all the ones I did (A10/A20/A31)...

> + * trees. If we find a node that is the frontend and is
> + * disabled, we should just follow through and parse its
> + * child, but without adding it to the component list.
> + * Otherwise, we obviously want to add it to the list.
> */
> if (!sun4i_drv_node_is_frontend(node) &&
> !of_device_is_available(node))
> @@ -254,7 +257,12 @@ static int sun4i_drv_add_endpoints(struct device *dev,
> if (sun4i_drv_node_is_connector(node))
> return 0;
>
> - if (!sun4i_drv_node_is_frontend(node)) {
> + /*
> + * If the device is either just a regular device, or an
> + * enabled frontend, we add it to our component list.
> + */
> + if (!sun4i_drv_node_is_frontend(node) ||
> + (sun4i_drv_node_is_frontend(node) && of_device_is_available(node))) {
> /* Add current component */
> DRM_DEBUG_DRIVER("Adding component %pOF\n", node);
> drm_of_component_match_add(dev, match, compare_of, node);
> diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.h b/drivers/gpu/drm/sun4i/sun4i_drv.h
> index a960c89270cc..9c26a345f85c 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_drv.h
> +++ b/drivers/gpu/drm/sun4i/sun4i_drv.h
> @@ -19,6 +19,7 @@
>
> struct sun4i_drv {
> struct list_head engine_list;
> + struct list_head frontend_list;
> struct list_head tcon_list;
>
> struct drm_fbdev_cma *fbdev;
> diff --git a/drivers/gpu/drm/sun4i/sun4i_frontend.c b/drivers/gpu/drm/sun4i/sun4i_frontend.c
> new file mode 100644
> index 000000000000..fb3e96ab57f7
> --- /dev/null
> +++ b/drivers/gpu/drm/sun4i/sun4i_frontend.c
> @@ -0,0 +1,392 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2017 Free Electrons
> + * Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> + */
> +#include <drm/drmP.h>
> +#include <drm/drm_gem_cma_helper.h>
> +#include <drm/drm_fb_cma_helper.h>
> +
> +#include <linux/clk.h>
> +#include <linux/component.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +
> +#include "sun4i_drv.h"
> +#include "sun4i_frontend.h"
> +
> +static const u32 sun4i_frontend_vert_coef[32] = {
> + 0x00004000, 0x000140ff, 0x00033ffe, 0x00043ffd,
> + 0x00063efc, 0xff083dfc, 0x000a3bfb, 0xff0d39fb,
> + 0xff0f37fb, 0xff1136fa, 0xfe1433fb, 0xfe1631fb,
> + 0xfd192ffb, 0xfd1c2cfb, 0xfd1f29fb, 0xfc2127fc,
> + 0xfc2424fc, 0xfc2721fc, 0xfb291ffd, 0xfb2c1cfd,
> + 0xfb2f19fd, 0xfb3116fe, 0xfb3314fe, 0xfa3611ff,
> + 0xfb370fff, 0xfb390dff, 0xfb3b0a00, 0xfc3d08ff,
> + 0xfc3e0600, 0xfd3f0400, 0xfe3f0300, 0xff400100,
> +};
> +
> +static const u32 sun4i_frontend_horz_coef[64] = {
> + 0x40000000, 0x00000000, 0x40fe0000, 0x0000ff03,
> + 0x3ffd0000, 0x0000ff05, 0x3ffc0000, 0x0000ff06,
> + 0x3efb0000, 0x0000ff08, 0x3dfb0000, 0x0000ff09,
> + 0x3bfa0000, 0x0000fe0d, 0x39fa0000, 0x0000fe0f,
> + 0x38fa0000, 0x0000fe10, 0x36fa0000, 0x0000fe12,
> + 0x33fa0000, 0x0000fd16, 0x31fa0000, 0x0000fd18,
> + 0x2ffa0000, 0x0000fd1a, 0x2cfa0000, 0x0000fc1e,
> + 0x29fa0000, 0x0000fc21, 0x27fb0000, 0x0000fb23,
> + 0x24fb0000, 0x0000fb26, 0x21fb0000, 0x0000fb29,
> + 0x1ffc0000, 0x0000fa2b, 0x1cfc0000, 0x0000fa2e,
> + 0x19fd0000, 0x0000fa30, 0x16fd0000, 0x0000fa33,
> + 0x14fd0000, 0x0000fa35, 0x11fe0000, 0x0000fa37,
> + 0x0ffe0000, 0x0000fa39, 0x0dfe0000, 0x0000fa3b,
> + 0x0afe0000, 0x0000fa3e, 0x08ff0000, 0x0000fb3e,
> + 0x06ff0000, 0x0000fb40, 0x05ff0000, 0x0000fc40,
> + 0x03ff0000, 0x0000fd41, 0x01ff0000, 0x0000fe42,
> +};
> +
> +static void sun4i_frontend_scaler_init(struct sun4i_frontend *frontend)
> +{
> + int i;
> +
> + for (i = 0; i < 32; i++) {
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_HORZCOEF0_REG(i),
> + sun4i_frontend_horz_coef[2 * i]);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_HORZCOEF0_REG(i),
> + sun4i_frontend_horz_coef[2 * i]);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_HORZCOEF1_REG(i),
> + sun4i_frontend_horz_coef[2 * i + 1]);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_HORZCOEF1_REG(i),
> + sun4i_frontend_horz_coef[2 * i + 1]);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_VERTCOEF_REG(i),
> + sun4i_frontend_vert_coef[i]);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_VERTCOEF_REG(i),
> + sun4i_frontend_vert_coef[i]);
> + }
> +
> + regmap_update_bits(frontend->regs, SUN4I_FRONTEND_FRM_CTRL_REG, BIT(23), BIT(23));
> +}
> +
> +int sun4i_frontend_init(struct sun4i_frontend *frontend)
> +{
> + return pm_runtime_get_sync(frontend->dev);
> +}
> +EXPORT_SYMBOL(sun4i_frontend_init);
> +
> +void sun4i_frontend_exit(struct sun4i_frontend *frontend)
> +{
> + pm_runtime_put(frontend->dev);
> +}
> +EXPORT_SYMBOL(sun4i_frontend_exit);
> +
> +void sun4i_frontend_update_buffer(struct sun4i_frontend *frontend,
> + struct drm_plane *plane)
> +{
> + struct drm_plane_state *state = plane->state;
> + struct drm_framebuffer *fb = state->fb;
> + struct drm_gem_cma_object *gem;
> + dma_addr_t paddr;
> + int bpp;
> +
> + /* Get the physical address of the buffer in memory */
> + gem = drm_fb_cma_get_gem_obj(fb, 0);
> +
> + DRM_DEBUG_DRIVER("Using GEM @ %pad\n", &gem->paddr);
> +
> + /* Set the line width */
> + DRM_DEBUG_DRIVER("Frontend stride: %d bytes\n", fb->pitches[0]);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_LINESTRD0_REG,
> + fb->pitches[0]);
> +
> + /* Compute the start of the displayed memory */
> + bpp = fb->format->cpp[0];
> + paddr = gem->paddr + fb->offsets[0];
> + paddr += (state->src_x >> 16) * bpp;
> + paddr += (state->src_y >> 16) * fb->pitches[0];

You can use drm_fb_cma_get_gem_addr(fb, state, 0), instead of open
coding it.

Do we need to convert the address, like with the backend?

> +
> + DRM_DEBUG_DRIVER("Setting buffer address to %pad\n", &paddr);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_BUF_ADDR0_REG, paddr);
> +}
> +EXPORT_SYMBOL(sun4i_frontend_update_buffer);
> +
> +static int sun4i_frontend_drm_format_to_input_fmt(uint32_t fmt, u32 *val)
> +{
> + switch (fmt) {
> + case DRM_FORMAT_ARGB8888:
> + case DRM_FORMAT_XRGB8888:
> + *val = 3;
> + return 0;
> +
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int sun4i_frontend_drm_format_to_output_fmt(uint32_t fmt, u32 *val)
> +{
> + switch (fmt) {
> + case DRM_FORMAT_ARGB8888:
> + *val = 2;
> + return 0;
> +
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +int sun4i_frontend_update_formats(struct sun4i_frontend *frontend,
> + struct drm_plane *plane, uint32_t out_fmt)
> +{
> + struct drm_plane_state *state = plane->state;
> + struct drm_framebuffer *fb = state->fb;
> + u32 out_fmt_val;
> + u32 in_fmt_val;
> + int ret;
> +
> + ret = sun4i_frontend_drm_format_to_input_fmt(fb->format->format,
> + &in_fmt_val);
> + if (ret) {
> + DRM_DEBUG_DRIVER("Invalid input format\n");
> + return ret;
> + }
> +
> + ret = sun4i_frontend_drm_format_to_output_fmt(out_fmt, &out_fmt_val);
> + if (ret) {
> + DRM_DEBUG_DRIVER("Invalid output format\n");
> + return ret;
> + }
> +
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_HORZPHASE_REG, 0x400);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_HORZPHASE_REG, 0x400);
> +
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_VERTPHASE0_REG, 0x400);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_VERTPHASE0_REG, 0x400);
> +
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_VERTPHASE1_REG, 0x400);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_VERTPHASE1_REG, 0x400);

I really don't understand any of this. :(

> +
> + regmap_write(frontend->regs, SUN4I_FRONTEND_INPUT_FMT_REG,
> + SUN4I_FRONTEND_INPUT_FMT_DATA_MOD(1) |
> + SUN4I_FRONTEND_INPUT_FMT_DATA_FMT(5) |
> + SUN4I_FRONTEND_INPUT_FMT_PS(1));
> + regmap_write(frontend->regs, SUN4I_FRONTEND_OUTPUT_FMT_REG,
> + SUN4I_FRONTEND_OUTPUT_FMT_DATA_FMT(1));

You don't seem to be using the values you got from the helper functions.
Moreover, they don't match the values you claim to support.

> +
> + return 0;
> +}
> +EXPORT_SYMBOL(sun4i_frontend_update_formats);
> +
> +void sun4i_frontend_update_coord(struct sun4i_frontend *frontend,
> + struct drm_plane *plane)
> +{
> + struct drm_plane_state *state = plane->state;
> +
> + /* Set height and width */
> + DRM_DEBUG_DRIVER("Frontend size W: %u H: %u\n",
> + state->crtc_w, state->crtc_h);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_INSIZE_REG,
> + SUN4I_FRONTEND_INSIZE(state->src_h >> 16,
> + state->src_w >> 16));
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_INSIZE_REG,
> + SUN4I_FRONTEND_INSIZE(state->src_h >> 16,
> + state->src_w >> 16));

Slighty off-topic, but does the kernel provide helpers for 16.16
fixed point arithmetic?

> +
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_OUTSIZE_REG,
> + SUN4I_FRONTEND_OUTSIZE(state->crtc_h, state->crtc_w));
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_OUTSIZE_REG,
> + SUN4I_FRONTEND_OUTSIZE(state->crtc_h, state->crtc_w));

Do you need to set the line stride registers?

> +
> + DRM_DEBUG_DRIVER("Frontend horizontal scaling factor %d.%d\n", 1, 0);

Value doesn't match what is programmed.

> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_HORZFACT_REG,
> + state->src_w / state->crtc_w);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_HORZFACT_REG,
> + state->src_w / state->crtc_w);
> +
> + DRM_DEBUG_DRIVER("Frontend vertical scaling factor %d.%d\n", 1, 0);

Neither does this.

> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH0_VERTFACT_REG,
> + state->src_h / state->crtc_h);
> + regmap_write(frontend->regs, SUN4I_FRONTEND_CH1_VERTFACT_REG,
> + state->src_h / state->crtc_h);

I don't think you need to program any of the channel 1 registers for
interleaved data.

> +
> + regmap_write_bits(frontend->regs, SUN4I_FRONTEND_FRM_CTRL_REG,
> + SUN4I_FRONTEND_FRM_CTRL_REG_RDY,
> + SUN4I_FRONTEND_FRM_CTRL_REG_RDY);
> +}
> +EXPORT_SYMBOL(sun4i_frontend_update_coord);
> +
> +int sun4i_frontend_enable(struct sun4i_frontend *frontend)
> +{
> + regmap_write_bits(frontend->regs, SUN4I_FRONTEND_FRM_CTRL_REG,
> + SUN4I_FRONTEND_FRM_CTRL_FRM_START,
> + SUN4I_FRONTEND_FRM_CTRL_FRM_START);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(sun4i_frontend_enable);
> +
> +static struct regmap_config sun4i_frontend_regmap_config = {
> + .reg_bits = 32,
> + .val_bits = 32,
> + .reg_stride = 4,
> + .max_register = 0x0a14,
> +};
> +
> +static int sun4i_frontend_bind(struct device *dev, struct device *master,
> + void *data)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct sun4i_frontend *frontend;
> + struct drm_device *drm = data;
> + struct sun4i_drv *drv = drm->dev_private;
> + struct resource *res;
> + void __iomem *regs;
> +
> + frontend = devm_kzalloc(dev, sizeof(*frontend), GFP_KERNEL);
> + if (!frontend)
> + return -ENOMEM;
> +
> + dev_set_drvdata(dev, frontend);
> + frontend->dev = dev;
> + frontend->node = dev->of_node;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + regs = devm_ioremap_resource(dev, res);
> + if (IS_ERR(regs))
> + return PTR_ERR(regs);
> +
> + frontend->regs = devm_regmap_init_mmio(dev, regs,
> + &sun4i_frontend_regmap_config);
> + if (IS_ERR(frontend->regs)) {
> + dev_err(dev, "Couldn't create the frontend regmap\n");
> + return PTR_ERR(frontend->regs);
> + }
> +
> + frontend->reset = devm_reset_control_get(dev, NULL);
> + if (IS_ERR(frontend->reset)) {
> + dev_err(dev, "Couldn't get our reset line\n");
> + return PTR_ERR(frontend->reset);
> + }
> +
> + frontend->bus_clk = devm_clk_get(dev, "ahb");
> + if (IS_ERR(frontend->bus_clk)) {
> + dev_err(dev, "Couldn't get our bus clock\n");
> + return PTR_ERR(frontend->bus_clk);
> + }
> +
> + frontend->mod_clk = devm_clk_get(dev, "mod");
> + if (IS_ERR(frontend->mod_clk)) {
> + dev_err(dev, "Couldn't get our mod clock\n");
> + return PTR_ERR(frontend->mod_clk);
> + }
> +
> + frontend->ram_clk = devm_clk_get(dev, "ram");
> + if (IS_ERR(frontend->ram_clk)) {
> + dev_err(dev, "Couldn't get our ram clock\n");
> + return PTR_ERR(frontend->ram_clk);
> + }
> +
> + list_add_tail(&frontend->list, &drv->frontend_list);

Maybe force a reset here?

> + pm_runtime_enable(dev);
> +
> + return 0;
> +}
> +
> +static void sun4i_frontend_unbind(struct device *dev, struct device *master,
> + void *data)
> +{
> + struct sun4i_frontend *frontend = dev_get_drvdata(dev);
> +
> + list_del(&frontend->list);
> + pm_runtime_force_suspend(dev);
> +}
> +
> +static const struct component_ops sun4i_frontend_ops = {
> + .bind = sun4i_frontend_bind,
> + .unbind = sun4i_frontend_unbind,
> +};
> +
> +static int sun4i_frontend_probe(struct platform_device *pdev)
> +{
> + return component_add(&pdev->dev, &sun4i_frontend_ops);
> +}
> +
> +static int sun4i_frontend_remove(struct platform_device *pdev)
> +{
> + component_del(&pdev->dev, &sun4i_frontend_ops);
> +
> + return 0;
> +}
> +
> +static int sun4i_frontend_runtime_resume(struct device *dev)
> +{
> + struct sun4i_frontend *frontend = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = reset_control_deassert(frontend->reset);
> + if (ret) {
> + dev_err(dev, "Couldn't deassert our reset line\n");
> + return ret;
> + }
> +
> + clk_set_rate(frontend->mod_clk, 300000000);
> +
> + clk_prepare_enable(frontend->bus_clk);
> + clk_prepare_enable(frontend->mod_clk);
> + clk_prepare_enable(frontend->ram_clk);

I wonder if the clocks should be enabled first, so the registers
and internal state gets properly reset?

> +
> + regmap_update_bits(frontend->regs, SUN4I_FRONTEND_EN_REG,
> + SUN4I_FRONTEND_EN_EN,
> + SUN4I_FRONTEND_EN_EN);
> +

You also need to set OUT_PORT_SEL in FRM_CTRL_REG so that frontend1
correctly outputs to backend1, assuming a static mapping.

> + regmap_update_bits(frontend->regs, SUN4I_FRONTEND_BYPASS_REG,
> + SUN4I_FRONTEND_BYPASS_CSC_EN,
> + SUN4I_FRONTEND_BYPASS_CSC_EN);
> +
> + sun4i_frontend_scaler_init(frontend);
> +
> + return 0;
> +}
> +
> +static int sun4i_frontend_runtime_suspend(struct device *dev)
> +{
> + struct sun4i_frontend *frontend = dev_get_drvdata(dev);
> +
> + clk_disable_unprepare(frontend->ram_clk);
> + clk_disable_unprepare(frontend->mod_clk);
> + clk_disable_unprepare(frontend->bus_clk);
> +
> + reset_control_assert(frontend->reset);
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops sun4i_frontend_pm_ops = {
> + .runtime_resume = sun4i_frontend_runtime_resume,
> + .runtime_suspend = sun4i_frontend_runtime_suspend,
> +};
> +
> +static const struct of_device_id sun4i_frontend_of_table[] = {
> + { .compatible = "allwinner,sun5i-a13-display-frontend" },
> + { .compatible = "allwinner,sun6i-a31-display-frontend" },

What about A10 and A20?

Regards
ChenYu

> + { .compatible = "allwinner,sun8i-a33-display-frontend" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, sun4i_frontend_of_table);
> +
> +static struct platform_driver sun4i_frontend_driver = {
> + .probe = sun4i_frontend_probe,
> + .remove = sun4i_frontend_remove,
> + .driver = {
> + .name = "sun4i-frontend",
> + .of_match_table = sun4i_frontend_of_table,
> + .pm = &sun4i_frontend_pm_ops,
> + },
> +};
> +module_platform_driver(sun4i_frontend_driver);
> +
> +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Allwinner A10 Display Engine Frontend Driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/gpu/drm/sun4i/sun4i_frontend.h b/drivers/gpu/drm/sun4i/sun4i_frontend.h
> new file mode 100644
> index 000000000000..5adc2c7266bc
> --- /dev/null
> +++ b/drivers/gpu/drm/sun4i/sun4i_frontend.h
> @@ -0,0 +1,96 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2017 Free Electrons
> + * Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> + */
> +
> +#ifndef _SUN4I_FRONTEND_H_
> +#define _SUN4I_FRONTEND_H_
> +
> +#include <linux/list.h>
> +
> +#define SUN4I_FRONTEND_EN_REG 0x000
> +#define SUN4I_FRONTEND_EN_EN BIT(0)
> +
> +#define SUN4I_FRONTEND_FRM_CTRL_REG 0x004
> +#define SUN4I_FRONTEND_FRM_CTRL_FRM_START BIT(16)
> +#define SUN4I_FRONTEND_FRM_CTRL_COEF_RDY BIT(1)
> +#define SUN4I_FRONTEND_FRM_CTRL_REG_RDY BIT(0)
> +
> +#define SUN4I_FRONTEND_BYPASS_REG 0x008
> +#define SUN4I_FRONTEND_BYPASS_CSC_EN BIT(1)
> +
> +#define SUN4I_FRONTEND_BUF_ADDR0_REG 0x020
> +
> +#define SUN4I_FRONTEND_LINESTRD0_REG 0x040
> +
> +#define SUN4I_FRONTEND_INPUT_FMT_REG 0x04c
> +#define SUN4I_FRONTEND_INPUT_FMT_DATA_MOD(mod) ((mod) << 8)
> +#define SUN4I_FRONTEND_INPUT_FMT_DATA_FMT(fmt) ((fmt) << 4)
> +#define SUN4I_FRONTEND_INPUT_FMT_PS(ps) (ps)
> +
> +#define SUN4I_FRONTEND_OUTPUT_FMT_REG 0x05c
> +#define SUN4I_FRONTEND_OUTPUT_FMT_DATA_FMT(fmt) (fmt)
> +
> +#define SUN4I_FRONTEND_CH0_INSIZE_REG 0x100
> +#define SUN4I_FRONTEND_INSIZE(h, w) ((((h) - 1) << 16) | (((w) - 1)))
> +
> +#define SUN4I_FRONTEND_CH0_OUTSIZE_REG 0x104
> +#define SUN4I_FRONTEND_OUTSIZE(h, w) ((((h) - 1) << 16) | (((w) - 1)))
> +
> +#define SUN4I_FRONTEND_CH0_HORZFACT_REG 0x108
> +#define SUN4I_FRONTEND_HORZFACT(i, f) (((i) << 16) | (f))
> +
> +#define SUN4I_FRONTEND_CH0_VERTFACT_REG 0x10c
> +#define SUN4I_FRONTEND_VERTFACT(i, f) (((i) << 16) | (f))
> +
> +#define SUN4I_FRONTEND_CH0_HORZPHASE_REG 0x110
> +#define SUN4I_FRONTEND_CH0_VERTPHASE0_REG 0x114
> +#define SUN4I_FRONTEND_CH0_VERTPHASE1_REG 0x118
> +
> +#define SUN4I_FRONTEND_CH1_INSIZE_REG 0x200
> +#define SUN4I_FRONTEND_CH1_OUTSIZE_REG 0x204
> +#define SUN4I_FRONTEND_CH1_HORZFACT_REG 0x208
> +#define SUN4I_FRONTEND_CH1_VERTFACT_REG 0x20c
> +
> +#define SUN4I_FRONTEND_CH1_HORZPHASE_REG 0x210
> +#define SUN4I_FRONTEND_CH1_VERTPHASE0_REG 0x214
> +#define SUN4I_FRONTEND_CH1_VERTPHASE1_REG 0x218
> +
> +#define SUN4I_FRONTEND_CH0_HORZCOEF0_REG(i) (0x400 + i * 4)
> +#define SUN4I_FRONTEND_CH0_HORZCOEF1_REG(i) (0x480 + i * 4)
> +#define SUN4I_FRONTEND_CH0_VERTCOEF_REG(i) (0x500 + i * 4)
> +#define SUN4I_FRONTEND_CH1_HORZCOEF0_REG(i) (0x600 + i * 4)
> +#define SUN4I_FRONTEND_CH1_HORZCOEF1_REG(i) (0x680 + i * 4)
> +#define SUN4I_FRONTEND_CH1_VERTCOEF_REG(i) (0x700 + i * 4)
> +
> +struct clk;
> +struct device_node;
> +struct drm_plane;
> +struct regmap;
> +struct reset_control;
> +
> +struct sun4i_frontend {
> + struct list_head list;
> + struct device *dev;
> + struct device_node *node;
> +
> + struct clk *bus_clk;
> + struct clk *mod_clk;
> + struct clk *ram_clk;
> + struct regmap *regs;
> + struct reset_control *reset;
> +};
> +
> +int sun4i_frontend_init(struct sun4i_frontend *frontend);
> +void sun4i_frontend_exit(struct sun4i_frontend *frontend);
> +int sun4i_frontend_enable(struct sun4i_frontend *frontend);
> +
> +void sun4i_frontend_update_buffer(struct sun4i_frontend *frontend,
> + struct drm_plane *plane);
> +void sun4i_frontend_update_coord(struct sun4i_frontend *frontend,
> + struct drm_plane *plane);
> +int sun4i_frontend_update_formats(struct sun4i_frontend *frontend,
> + struct drm_plane *plane, uint32_t out_fmt);
> +
> +#endif /* _SUN4I_FRONTEND_H_ */
> --
> git-series 0.9.1