6.12-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Zimmermann tzimmermann@suse.de
[ Upstream commit 5d08c44e47b9d41366714552bdd374ac4b595591 ]
Add an fbdev client that can work with any memory manager. The client implementation is the same as existing code in fbdev-dma or fbdev-shmem.
Provide struct drm_driver.fbdev_probe for the new client to allocate the surface GEM buffer. The new callback replaces fb_probe of struct drm_fb_helper_funcs, which does the same.
To use the new client, DRM drivers set fbdev_probe in their struct drm_driver instance and call drm_fbdev_client_setup(). Probing and creating the fbdev surface buffer is now independent from the other operations in struct drm_fb_helper. For the pixel format, the fbdev client either uses a specified format, the value in preferred_depth or 32-bit RGB.
v2: - test for struct drm_fb_helper.funcs for NULL (Sui) - respect struct drm_mode_config.preferred_depth for default format
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Reviewed-by: Javier Martinez Canillas javierm@redhat.com Link: https://patchwork.freedesktop.org/patch/msgid/20240924071734.98201-4-tzimmer... Stable-dep-of: 6b481ab0e685 ("drm/nouveau: select FW caching") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/Makefile | 4 +- drivers/gpu/drm/drm_fb_helper.c | 15 +-- drivers/gpu/drm/drm_fbdev_client.c | 141 +++++++++++++++++++++++++++++ include/drm/drm_drv.h | 18 ++++ include/drm/drm_fbdev_client.h | 19 ++++ 5 files changed, 190 insertions(+), 7 deletions(-) create mode 100644 drivers/gpu/drm/drm_fbdev_client.c create mode 100644 include/drm/drm_fbdev_client.h
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 84746054c721a..a1dd0909fa38b 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -145,7 +145,9 @@ drm_kms_helper-y := \ drm_self_refresh_helper.o \ drm_simple_kms_helper.o drm_kms_helper-$(CONFIG_DRM_PANEL_BRIDGE) += bridge/panel.o -drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fb_helper.o +drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += \ + drm_fbdev_client.o \ + drm_fb_helper.o obj-$(CONFIG_DRM_KMS_HELPER) += drm_kms_helper.o
# diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 29b0cf3a3fb19..b15ddbd65e7b5 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -492,8 +492,8 @@ EXPORT_SYMBOL(drm_fb_helper_init); * @fb_helper: driver-allocated fbdev helper * * A helper to alloc fb_info and the member cmap. Called by the driver - * within the fb_probe fb_helper callback function. Drivers do not - * need to release the allocated fb_info structure themselves, this is + * within the struct &drm_driver.fbdev_probe callback function. Drivers do + * not need to release the allocated fb_info structure themselves, this is * automatically done when calling drm_fb_helper_fini(). * * RETURNS: @@ -1610,7 +1610,7 @@ static int drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper,
/* * Allocates the backing storage and sets up the fbdev info structure through - * the ->fb_probe callback. + * the ->fbdev_probe callback. */ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper) { @@ -1628,7 +1628,10 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper) }
/* push down into drivers */ - ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes); + if (dev->driver->fbdev_probe) + ret = dev->driver->fbdev_probe(fb_helper, &sizes); + else if (fb_helper->funcs) + ret = fb_helper->funcs->fb_probe(fb_helper, &sizes); if (ret < 0) return ret;
@@ -1700,7 +1703,7 @@ static void drm_fb_helper_fill_var(struct fb_info *info, * instance and the drm framebuffer allocated in &drm_fb_helper.fb. * * Drivers should call this (or their equivalent setup code) from their - * &drm_fb_helper_funcs.fb_probe callback after having allocated the fbdev + * &drm_driver.fbdev_probe callback after having allocated the fbdev * backing storage framebuffer. */ void drm_fb_helper_fill_info(struct fb_info *info, @@ -1856,7 +1859,7 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper) * Note that this also registers the fbdev and so allows userspace to call into * the driver through the fbdev interfaces. * - * This function will call down into the &drm_fb_helper_funcs.fb_probe callback + * This function will call down into the &drm_driver.fbdev_probe callback * to let the driver allocate and initialize the fbdev info structure and the * drm framebuffer used to back the fbdev. drm_fb_helper_fill_info() is provided * as a helper to setup simple default values for the fbdev info structure. diff --git a/drivers/gpu/drm/drm_fbdev_client.c b/drivers/gpu/drm/drm_fbdev_client.c new file mode 100644 index 0000000000000..a09382afe2fb6 --- /dev/null +++ b/drivers/gpu/drm/drm_fbdev_client.c @@ -0,0 +1,141 @@ +// SPDX-License-Identifier: MIT + +#include <drm/drm_client.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_fbdev_client.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_fourcc.h> +#include <drm/drm_print.h> + +/* + * struct drm_client_funcs + */ + +static void drm_fbdev_client_unregister(struct drm_client_dev *client) +{ + struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client); + + if (fb_helper->info) { + drm_fb_helper_unregister_info(fb_helper); + } else { + drm_client_release(&fb_helper->client); + drm_fb_helper_unprepare(fb_helper); + kfree(fb_helper); + } +} + +static int drm_fbdev_client_restore(struct drm_client_dev *client) +{ + drm_fb_helper_lastclose(client->dev); + + return 0; +} + +static int drm_fbdev_client_hotplug(struct drm_client_dev *client) +{ + struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client); + struct drm_device *dev = client->dev; + int ret; + + if (dev->fb_helper) + return drm_fb_helper_hotplug_event(dev->fb_helper); + + ret = drm_fb_helper_init(dev, fb_helper); + if (ret) + goto err_drm_err; + + if (!drm_drv_uses_atomic_modeset(dev)) + drm_helper_disable_unused_functions(dev); + + ret = drm_fb_helper_initial_config(fb_helper); + if (ret) + goto err_drm_fb_helper_fini; + + return 0; + +err_drm_fb_helper_fini: + drm_fb_helper_fini(fb_helper); +err_drm_err: + drm_err(dev, "fbdev: Failed to setup emulation (ret=%d)\n", ret); + return ret; +} + +static const struct drm_client_funcs drm_fbdev_client_funcs = { + .owner = THIS_MODULE, + .unregister = drm_fbdev_client_unregister, + .restore = drm_fbdev_client_restore, + .hotplug = drm_fbdev_client_hotplug, +}; + +/** + * drm_fbdev_client_setup() - Setup fbdev emulation + * @dev: DRM device + * @format: Preferred color format for the device. DRM_FORMAT_XRGB8888 + * is used if this is zero. + * + * This function sets up fbdev emulation. Restore, hotplug events and + * teardown are all taken care of. Drivers that do suspend/resume need + * to call drm_fb_helper_set_suspend_unlocked() themselves. Simple + * drivers might use drm_mode_config_helper_suspend(). + * + * This function is safe to call even when there are no connectors present. + * Setup will be retried on the next hotplug event. + * + * The fbdev client is destroyed by drm_dev_unregister(). + * + * Returns: + * 0 on success, or a negative errno code otherwise. + */ +int drm_fbdev_client_setup(struct drm_device *dev, const struct drm_format_info *format) +{ + struct drm_fb_helper *fb_helper; + unsigned int color_mode; + int ret; + + /* TODO: Use format info throughout DRM */ + if (format) { + unsigned int bpp = drm_format_info_bpp(format, 0); + + switch (bpp) { + case 16: + color_mode = format->depth; // could also be 15 + break; + default: + color_mode = bpp; + } + } else { + switch (dev->mode_config.preferred_depth) { + case 0: + case 24: + color_mode = 32; + break; + default: + color_mode = dev->mode_config.preferred_depth; + } + } + + drm_WARN(dev, !dev->registered, "Device has not been registered.\n"); + drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n"); + + fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL); + if (!fb_helper) + return -ENOMEM; + drm_fb_helper_prepare(dev, fb_helper, color_mode, NULL); + + ret = drm_client_init(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs); + if (ret) { + drm_err(dev, "Failed to register client: %d\n", ret); + goto err_drm_client_init; + } + + drm_client_register(&fb_helper->client); + + return 0; + +err_drm_client_init: + drm_fb_helper_unprepare(fb_helper); + kfree(fb_helper); + return ret; +} +EXPORT_SYMBOL(drm_fbdev_client_setup); diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h index 02ea4e3248fdf..36a606af4ba1d 100644 --- a/include/drm/drm_drv.h +++ b/include/drm/drm_drv.h @@ -34,6 +34,8 @@
#include <drm/drm_device.h>
+struct drm_fb_helper; +struct drm_fb_helper_surface_size; struct drm_file; struct drm_gem_object; struct drm_master; @@ -366,6 +368,22 @@ struct drm_driver { struct drm_device *dev, uint32_t handle, uint64_t *offset);
+ /** + * @fbdev_probe + * + * Allocates and initialize the fb_info structure for fbdev emulation. + * Furthermore it also needs to allocate the DRM framebuffer used to + * back the fbdev. + * + * This callback is mandatory for fbdev support. + * + * Returns: + * + * 0 on success ot a negative error code otherwise. + */ + int (*fbdev_probe)(struct drm_fb_helper *fbdev_helper, + struct drm_fb_helper_surface_size *sizes); + /** * @show_fdinfo: * diff --git a/include/drm/drm_fbdev_client.h b/include/drm/drm_fbdev_client.h new file mode 100644 index 0000000000000..e11a5614f127c --- /dev/null +++ b/include/drm/drm_fbdev_client.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: MIT */ + +#ifndef DRM_FBDEV_CLIENT_H +#define DRM_FBDEV_CLIENT_H + +struct drm_device; +struct drm_format_info; + +#ifdef CONFIG_DRM_FBDEV_EMULATION +int drm_fbdev_client_setup(struct drm_device *dev, const struct drm_format_info *format); +#else +static inline int drm_fbdev_client_setup(struct drm_device *dev, + const struct drm_format_info *format) +{ + return 0; +} +#endif + +#endif