Re: [v3 3/6] drm/vs: Register DRM device

From: Dmitry Baryshkov
Date: Tue Dec 05 2023 - 06:34:37 EST

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In reply to: Philipp Zabel: "Re: [v3 3/6] drm/vs: Register DRM device"
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On Mon, 4 Dec 2023 at 14:33, Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx> wrote:
>
> Implement drm device registration interface
>
> Signed-off-by: Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx>
> ---
> MAINTAINERS | 1 +
> drivers/gpu/drm/Kconfig | 2 +
> drivers/gpu/drm/Makefile | 1 +
> drivers/gpu/drm/verisilicon/Kconfig | 13 +
> drivers/gpu/drm/verisilicon/Makefile | 6 +
> drivers/gpu/drm/verisilicon/vs_drv.c | 316 +++++++++++++++++++++++
> drivers/gpu/drm/verisilicon/vs_drv.h | 42 +++
> drivers/gpu/drm/verisilicon/vs_modeset.c | 39 +++
> drivers/gpu/drm/verisilicon/vs_modeset.h | 10 +
> 9 files changed, 430 insertions(+)
> create mode 100644 drivers/gpu/drm/verisilicon/Kconfig
> create mode 100644 drivers/gpu/drm/verisilicon/Makefile
> create mode 100644 drivers/gpu/drm/verisilicon/vs_drv.c
> create mode 100644 drivers/gpu/drm/verisilicon/vs_drv.h
> create mode 100644 drivers/gpu/drm/verisilicon/vs_modeset.c
> create mode 100644 drivers/gpu/drm/verisilicon/vs_modeset.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7caaadb83f3f..8dc9ebfe4605 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6887,6 +6887,7 @@ L: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> S: Maintained
> T: git git://anongit.freedesktop.org/drm/drm-misc
> F: Documentation/devicetree/bindings/display/starfive/
> +F: drivers/gpu/drm/verisilicon/
>
> DRM DRIVER FOR TI DLPC3433 MIPI DSI TO DMD BRIDGE
> M: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
> index 3eee8636f847..e8d53c2e7c86 100644
> --- a/drivers/gpu/drm/Kconfig
> +++ b/drivers/gpu/drm/Kconfig
> @@ -394,6 +394,8 @@ source "drivers/gpu/drm/solomon/Kconfig"
>
> source "drivers/gpu/drm/sprd/Kconfig"
>
> +source "drivers/gpu/drm/verisilicon/Kconfig"
> +
> config DRM_HYPERV
> tristate "DRM Support for Hyper-V synthetic video device"
> depends on DRM && PCI && MMU && HYPERV
> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
> index 8e1bde059170..29e04acded06 100644
> --- a/drivers/gpu/drm/Makefile
> +++ b/drivers/gpu/drm/Makefile
> @@ -198,3 +198,4 @@ obj-$(CONFIG_DRM_HYPERV) += hyperv/
> obj-y += solomon/
> obj-$(CONFIG_DRM_SPRD) += sprd/
> obj-$(CONFIG_DRM_LOONGSON) += loongson/
> +obj-$(CONFIG_DRM_VERISILICON) += verisilicon/
> diff --git a/drivers/gpu/drm/verisilicon/Kconfig b/drivers/gpu/drm/verisilicon/Kconfig
> new file mode 100644
> index 000000000000..e10fa97635aa
> --- /dev/null
> +++ b/drivers/gpu/drm/verisilicon/Kconfig
> @@ -0,0 +1,13 @@
> +# SPDX-License-Identifier: GPL-2.0
> +config DRM_VERISILICON
> + tristate "DRM Support for VeriSilicon"
> + depends on DRM
> + select DRM_KMS_HELPER
> + select DRM_GEM_DMA_HELPER
> + select CMA
> + select DMA_CMA
> + help
> + Choose this option if you have a VeriSilicon soc chipset.
> + This driver provides VeriSilicon kernel mode
> + setting and buffer management. It does not
> + provide 2D or 3D acceleration.
> diff --git a/drivers/gpu/drm/verisilicon/Makefile b/drivers/gpu/drm/verisilicon/Makefile
> new file mode 100644
> index 000000000000..d785a1dfaa7f
> --- /dev/null
> +++ b/drivers/gpu/drm/verisilicon/Makefile
> @@ -0,0 +1,6 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +vs_drm-objs := vs_drv.o \
> + vs_modeset.o
> +
> +obj-$(CONFIG_DRM_VERISILICON) += vs_drm.o
> diff --git a/drivers/gpu/drm/verisilicon/vs_drv.c b/drivers/gpu/drm/verisilicon/vs_drv.c
> new file mode 100644
> index 000000000000..4fb1f29ef84b
> --- /dev/null
> +++ b/drivers/gpu/drm/verisilicon/vs_drv.c
> @@ -0,0 +1,316 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2023 VeriSilicon Holdings Co., Ltd.
> + */
> +#include <linux/clk.h>
> +#include <linux/component.h>
> +#include <linux/of_clk.h>
> +#include <linux/pm_runtime.h>
> +
> +#include <drm/drm_aperture.h>
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/drm_fb_helper.h>
> +#include <drm/drm_fbdev_generic.h>
> +#include <drm/drm_file.h>
> +#include <drm/drm_gem_dma_helper.h>
> +#include <drm/drm_module.h>
> +#include <drm/drm_of.h>
> +#include <drm/drm_probe_helper.h>
> +#include <drm/drm_vblank.h>
> +
> +#include "vs_drv.h"
> +#include "vs_modeset.h"
> +
> +#define DRV_NAME "verisilicon"
> +#define DRV_DESC "Verisilicon DRM driver"
> +#define DRV_DATE "20230516"
> +#define DRV_MAJOR 1
> +#define DRV_MINOR 0
> +
> +static int vs_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
> + struct drm_mode_create_dumb *args)
> +{
> + struct vs_drm_device *priv = to_vs_drm_private(dev);
> + unsigned int pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
> +
> + args->pitch = ALIGN(pitch, priv->pitch_alignment);
> + return drm_gem_dma_dumb_create_internal(file, dev, args);
> +}
> +
> +DEFINE_DRM_GEM_FOPS(vs_drm_fops);
> +
> +static struct drm_driver vs_drm_driver = {
> + .driver_features = DRIVER_MODESET | DRIVER_ATOMIC | DRIVER_GEM,
> +
> + DRM_GEM_DMA_DRIVER_OPS_WITH_DUMB_CREATE(vs_gem_dumb_create),
> +
> + .fops = &vs_drm_fops,
> + .name = DRV_NAME,
> + .desc = DRV_DESC,
> + .date = DRV_DATE,
> + .major = DRV_MAJOR,
> + .minor = DRV_MINOR,
> +};
> +
> +static void vs_drm_device_release_clocks(void *res)
> +{
> + struct vs_drm_device *priv = res;
> + unsigned int i;
> +
> + reset_control_bulk_assert(priv->nrsts, priv->rst_vout);
> +
> + for (i = 0; i < priv->clk_count; ++i) {
> + if (priv->clks[i]) {
> + clk_disable_unprepare(priv->clks[i]);
> + clk_put(priv->clks[i]);
> + }
> + }
> +}
> +
> +static const char * const vout_resets[] = {
> + "axi",
> + "ahb",
> + "core",
> +};
> +
> +static int vs_drm_device_init_clocks(struct vs_drm_device *priv)
> +{
> + struct drm_device *dev = &priv->base;
> + struct platform_device *pdev = to_platform_device(dev->dev);
> + struct device_node *of_node = pdev->dev.of_node;
> + struct clk *clock;
> + unsigned int i;
> + int ret;
> +
> + if (dev_get_platdata(&pdev->dev) || !of_node)
> + return 0;

Drop dev_get_platdata(), you don't seem to use it.

> +
> + priv->nrsts = ARRAY_SIZE(priv->rst_vout);
> + for (int i = 0; i < priv->nrsts; ++i)
> + priv->rst_vout[i].id = vout_resets[i];
> + ret = devm_reset_control_bulk_get_shared(dev->dev, priv->nrsts,
> + priv->rst_vout);
> + if (ret) {
> + drm_err(dev, "Failed to get reset controls\n");
> + return ret;
> + }
> +
> + priv->clk_count = of_clk_get_parent_count(of_node);
> + if (!priv->clk_count)
> + return 0;
> +
> + priv->clks = drmm_kzalloc(dev, priv->clk_count * sizeof(priv->clks[0]),
> + GFP_KERNEL);
> + if (!priv->clks)
> + return -ENOMEM;
> +
> + for (i = 0; i < priv->clk_count; ++i) {
> + clock = of_clk_get(of_node, i);
> + if (IS_ERR(clock)) {
> + ret = PTR_ERR(clock);
> + if (ret == -EPROBE_DEFER)
> + goto err;
> + drm_err(dev, "clock %u not found: %d\n", i, ret);
> + continue;
> + }
> + ret = clk_prepare_enable(clock);
> + if (ret) {
> + drm_err(dev, "failed to enable clock %u: %d\n",
> + i, ret);
> + clk_put(clock);
> + continue;
> + }
> + priv->clks[i] = clock;
> + }

This can be rewritten as devm_clk_bulk_get_all()

> +
> + ret = reset_control_bulk_deassert(priv->nrsts, priv->rst_vout);
> + if (ret)
> + return ret;

It is a bad idea to mix get_resources kind of function with the actual
resource control. Please move reset deassertion upwards.

> +
> + return devm_add_action_or_reset(&pdev->dev,
> + vs_drm_device_release_clocks,
> + priv);
> +
> +err:
> + while (i) {
> + --i;
> + if (priv->clks[i]) {
> + clk_disable_unprepare(priv->clks[i]);
> + clk_put(priv->clks[i]);
> + }
> + }
> + return ret;
> +}
> +
> +static int vs_drm_bind(struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct vs_drm_device *priv;
> + int ret;
> + struct drm_device *drm_dev;
> +
> + /* Remove existing drivers that may own the framebuffer memory. */
> + ret = drm_aperture_remove_framebuffers(&vs_drm_driver);
> + if (ret)
> + return ret;

If anything happens during the probe, your platform is left with no
display output. I think it might be better to call this when the
driver has acquired all the resources and is ready to start hw init.

> +
> + priv = devm_drm_dev_alloc(dev, &vs_drm_driver, struct vs_drm_device, base);
> + if (IS_ERR(priv))
> + return PTR_ERR(priv);
> +
> + priv->pitch_alignment = 64;
> +
> + ret = dma_set_coherent_mask(priv->base.dev, DMA_BIT_MASK(40));
> + if (ret)
> + return ret;
> +
> + drm_dev = &priv->base;
> + platform_set_drvdata(pdev, drm_dev);
> +
> + ret = vs_drm_device_init_clocks(priv);
> + if (ret)
> + return ret;
> +
> + vs_mode_config_init(drm_dev);
> +
> + /* Now try and bind all our sub-components */
> + ret = component_bind_all(dev, drm_dev);
> + if (ret)
> + return ret;
> +
> + ret = drm_vblank_init(drm_dev, drm_dev->mode_config.num_crtc);
> + if (ret)
> + return ret;
> +
> + drm_mode_config_reset(drm_dev);
> +
> + drm_kms_helper_poll_init(drm_dev);
> +
> + ret = drm_dev_register(drm_dev, 0);
> + if (ret)
> + return ret;

Teardown path is missing.

> +
> + drm_fbdev_generic_setup(drm_dev, 32);
> +
> + return 0;
> +}
> +
> +static void vs_drm_unbind(struct device *dev)
> +{
> + struct drm_device *drm_dev = dev_get_drvdata(dev);
> +
> + drm_dev_unregister(drm_dev);
> + drm_kms_helper_poll_fini(drm_dev);
> + component_unbind_all(drm_dev->dev, drm_dev);
> +}
> +
> +static const struct component_master_ops vs_drm_ops = {
> + .bind = vs_drm_bind,
> + .unbind = vs_drm_unbind,
> +};
> +
> +static struct platform_driver *drm_sub_drivers[] = {
> +};
> +
> +static struct component_match *vs_drm_match_add(struct device *dev)
> +{
> + struct component_match *match = NULL;
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(drm_sub_drivers); ++i) {
> + struct platform_driver *drv = drm_sub_drivers[i];
> + struct device *p = NULL, *d;
> +
> + while ((d = platform_find_device_by_driver(p, &drv->driver))) {
> + put_device(p);
> +
> + drm_of_component_match_add(dev, &match, component_compare_of,
> + d->of_node);
> + p = d;
> + }
> + put_device(p);
> + }
> +
> + return match ? match : ERR_PTR(-ENODEV);
> +}
> +
> +static int vs_drm_platform_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct component_match *match;
> +
> + match = vs_drm_match_add(dev);
> + if (IS_ERR(match))
> + return PTR_ERR(match);
> +
> + return component_master_add_with_match(dev, &vs_drm_ops, match);

I wonder if you can use drm_of_component_probe() instead?

> +}
> +
> +static int vs_drm_platform_remove(struct platform_device *pdev)

I think this should be void vs_drm_platform_remove() and .remove_new

> +{
> + component_master_del(&pdev->dev, &vs_drm_ops);
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int vs_drm_suspend(struct device *dev)
> +{
> + return drm_mode_config_helper_suspend(dev_get_drvdata(dev));
> +}
> +
> +static int vs_drm_resume(struct device *dev)
> +{
> + drm_mode_config_helper_resume(dev_get_drvdata(dev));

return drm_mode_config_helper_resume()

> +
> + return 0;
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(vs_drm_pm_ops, vs_drm_suspend, vs_drm_resume);
> +
> +static const struct of_device_id vs_drm_dt_ids[] = {
> + { .compatible = "starfive,display-subsystem", },
> + { },
> +};
> +
> +MODULE_DEVICE_TABLE(of, vs_drm_dt_ids);
> +
> +static struct platform_driver vs_drm_platform_driver = {
> + .probe = vs_drm_platform_probe,
> + .remove = vs_drm_platform_remove,
> +
> + .driver = {
> + .name = DRV_NAME,
> + .of_match_table = vs_drm_dt_ids,
> + .pm = &vs_drm_pm_ops,
> + },
> +};
> +
> +static int __init vs_drm_init(void)
> +{
> + int ret;
> +
> + ret = platform_register_drivers(drm_sub_drivers, ARRAY_SIZE(drm_sub_drivers));
> + if (ret)
> + return ret;
> +
> + ret = drm_platform_driver_register(&vs_drm_platform_driver);
> + if (ret)
> + platform_unregister_drivers(drm_sub_drivers, ARRAY_SIZE(drm_sub_drivers));
> +
> + return ret;
> +}
> +
> +static void __exit vs_drm_fini(void)
> +{
> + platform_driver_unregister(&vs_drm_platform_driver);
> + platform_unregister_drivers(drm_sub_drivers, ARRAY_SIZE(drm_sub_drivers));
> +}
> +
> +late_initcall_sync(vs_drm_init);
> +module_exit(vs_drm_fini);
> +
> +MODULE_DESCRIPTION("VeriSilicon DRM Driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/gpu/drm/verisilicon/vs_drv.h b/drivers/gpu/drm/verisilicon/vs_drv.h
> new file mode 100644
> index 000000000000..ea2189772980
> --- /dev/null
> +++ b/drivers/gpu/drm/verisilicon/vs_drv.h
> @@ -0,0 +1,42 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2023 VeriSilicon Holdings Co., Ltd.
> + */
> +
> +#ifndef __VS_DRV_H__
> +#define __VS_DRV_H__
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <drm/drm_drv.h>
> +#include <drm/drm_gem.h>
> +#include <drm/drm_managed.h>
> +#include <linux/clk.h>
> +#include <linux/reset.h>
> +
> +enum rst_vout {
> + RST_VOUT_AXI = 0,
> + RST_VOUT_AHB,
> + RST_VOUT_CORE,
> + RST_VOUT_NUM
> +};

Do you need these values? They can easily get out of sync with vout_rsts.

> +
> +/*@pitch_alignment: buffer pitch alignment required by sub-devices.*/
> +struct vs_drm_device {
> + struct drm_device base;
> + unsigned int pitch_alignment;
> + /* clocks */
> + unsigned int clk_count;
> + struct clk **clks;
> +
> + struct reset_control_bulk_data rst_vout[RST_VOUT_NUM];
> + int nrsts;
> +};
> +
> +static inline struct vs_drm_device *
> +to_vs_drm_private(const struct drm_device *dev)
> +{
> + return container_of(dev, struct vs_drm_device, base);
> +}
> +
> +#endif /* __VS_DRV_H__ */
> diff --git a/drivers/gpu/drm/verisilicon/vs_modeset.c b/drivers/gpu/drm/verisilicon/vs_modeset.c
> new file mode 100644
> index 000000000000..eaf406c1b7c7
> --- /dev/null
> +++ b/drivers/gpu/drm/verisilicon/vs_modeset.c
> @@ -0,0 +1,39 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2023 VeriSilicon Holdings Co., Ltd.
> + */
> +
> +#include <linux/module.h>
> +
> +#include <drm/drm_damage_helper.h>
> +#include <drm/drm_fb_helper.h>
> +#include <drm/drm_gem_framebuffer_helper.h>
> +
> +#include "vs_modeset.h"
> +
> +static const struct drm_mode_config_funcs vs_mode_config_funcs = {
> + .fb_create = drm_gem_fb_create,
> + .atomic_check = drm_atomic_helper_check,
> + .atomic_commit = drm_atomic_helper_commit,
> +};
> +
> +static struct drm_mode_config_helper_funcs vs_mode_config_helpers = {
> + .atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
> +};
> +
> +void vs_mode_config_init(struct drm_device *dev)
> +{
> + int ret;
> +
> + ret = drmm_mode_config_init(dev);
> + if (ret)
> + return;
> +
> + dev->mode_config.min_width = 0;
> + dev->mode_config.min_height = 0;
> + dev->mode_config.max_width = 4096;
> + dev->mode_config.max_height = 4096;
> +
> + dev->mode_config.funcs = &vs_mode_config_funcs;
> + dev->mode_config.helper_private = &vs_mode_config_helpers;
> +}
> diff --git a/drivers/gpu/drm/verisilicon/vs_modeset.h b/drivers/gpu/drm/verisilicon/vs_modeset.h
> new file mode 100644
> index 000000000000..bd04f81d2ad2
> --- /dev/null
> +++ b/drivers/gpu/drm/verisilicon/vs_modeset.h
> @@ -0,0 +1,10 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2020 VeriSilicon Holdings Co., Ltd.
> + */
> +
> +#ifndef __VS_MODESET_H__
> +#define __VS_MODESET_H__
> +
> +void vs_mode_config_init(struct drm_device *dev);
> +#endif /* __VS_FB_H__ */
> --
> 2.34.1
>

--
With best wishes
Dmitry

Next message: Yunsheng Lin: "[PATCH net-next 1/6] mm/page_alloc: modify page_frag_alloc_align() to accept align as an argument"
Previous message: Geert Uytterhoeven: "Re: [PATCH] [mfd] da9052: Add error handling for spi_setup in da9052_spi_probe"
In reply to: Philipp Zabel: "Re: [v3 3/6] drm/vs: Register DRM device"
Next in thread: Keith Zhao: "[v3 5/6] drm/vs: Add hdmi driver"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]