| Message ID | 20180103222110.45855-8-noralf@tronnes.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jan 03, 2018 at 11:21:09PM +0100, Noralf Trønnes wrote: > Add generic fbdev emulation which uses a drm_file to get a dumb_buffer > and drm_framebuffer. The buffer is exported and vmap/mmap called on > the dma-buf. > > Signed-off-by: Noralf Trønnes <noralf@tronnes.org> > --- > drivers/gpu/drm/drm_fb_helper.c | 301 +++++++++++++++++++++++++++++++++++++++- > include/drm/drm_fb_helper.h | 33 +++++ > 2 files changed, 333 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index f9dcc7a5761f..270ff6dc8045 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -30,12 +30,15 @@ > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > #include <linux/console.h> > +#include <linux/dma-buf.h> > #include <linux/kernel.h> > #include <linux/sysrq.h> > #include <linux/slab.h> > #include <linux/module.h> > #include <drm/drmP.h> > +#include <drm/drm_auth.h> > #include <drm/drm_crtc.h> > +#include <drm/drm_dumb_buffers.h> > #include <drm/drm_fb_helper.h> > #include <drm/drm_crtc_helper.h> > #include <drm/drm_atomic.h> > @@ -1951,7 +1954,9 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, > if (fb_helper->fbdev->fbops->fb_open == drm_fb_helper_fb_open) > atomic_set(&fb_helper->open_count, 0); > > - strcpy(fb_helper->fb->comm, "[fbcon]"); > + if (fb_helper->fb) > + strcpy(fb_helper->fb->comm, "[fbcon]"); > + > return 0; > } > > @@ -2975,6 +2980,300 @@ void drm_fb_helper_output_poll_changed(struct drm_device *dev) > } > EXPORT_SYMBOL(drm_fb_helper_output_poll_changed); > > +static struct fb_deferred_io drm_fb_helper_generic_defio = { > + .delay = HZ / 20, > + .deferred_io = drm_fb_helper_deferred_io, > +}; > + > +static int drm_fb_helper_generic_alloc_buf(struct drm_fb_helper *fb_helper) > +{ > + struct drm_fb_helper_surface_size *sizes = &fb_helper->sizes; > + struct drm_mode_create_dumb dumb_args = { 0 }; > + struct drm_prime_handle prime_args = { 0 }; > + struct drm_mode_fb_cmd2 fb_args = { 0 }; > + struct drm_device *dev = fb_helper->dev; > + struct fb_info *fbi = fb_helper->fbdev; > + struct drm_framebuffer *fb; > + struct dma_buf *dma_buf; > + struct drm_file *file; > + void *vaddr; > + int ret; > + > + file = drm_file_alloc(dev->primary); > + if (IS_ERR(file)) > + return PTR_ERR(file); > + > + drm_dropmaster_ioctl(dev, NULL, file); Hm .... why do we need this? Feels a bit like drm_file_alloc shouldn't do the entire master dance for us ... Otherwise this looks awesome, I really like it. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> -Daniel > + > + dumb_args.width = sizes->surface_width; > + dumb_args.height = sizes->surface_height; > + dumb_args.bpp = sizes->surface_bpp; > + ret = drm_mode_create_dumb_ioctl(dev, &dumb_args, file); > + if (ret) > + goto err_free_file; > + > + fb_args.width = dumb_args.width; > + fb_args.height = dumb_args.height; > + fb_args.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp, > + sizes->surface_depth); > + fb_args.handles[0] = dumb_args.handle; > + fb_args.pitches[0] = dumb_args.pitch; > + ret = drm_mode_addfb2(dev, &fb_args, file); > + if (ret) > + goto err_free_file; > + > + fb = drm_framebuffer_lookup(dev, file, fb_args.fb_id); > + if (!fb) { > + ret = -ENOENT; > + goto err_free_file; > + } > + > + /* drop the reference we picked up in framebuffer lookup */ > + drm_framebuffer_put(fb); > + > + strcpy(fb->comm, "[fbcon]"); > + > + prime_args.handle = dumb_args.handle; > + ret = drm_prime_handle_to_fd_ioctl(dev, &prime_args, file); > + if (ret) > + goto err_free_file; > + > + dma_buf = dma_buf_get(prime_args.fd); > + if (WARN_ON(IS_ERR(dma_buf))) { > + ret = PTR_ERR(dma_buf); > + goto err_free_file; > + } > + > + vaddr = dma_buf_vmap(dma_buf); > + if (!vaddr) { > + ret = -ENOMEM; > + goto err_put_dmabuf; > + } > + > + if (fb->funcs->dirty) { > + fbi->fbdefio = &drm_fb_helper_generic_defio; > + fb_deferred_io_init(fbi); > + } > + > + fbi->screen_size = fb->height * fb->pitches[0]; > + fbi->fix.smem_len = fbi->screen_size; > + fbi->screen_buffer = vaddr; > + > + fb_helper->dma_buf = dma_buf; > + fb_helper->file = file; > + > + mutex_lock(&fb_helper->lock); > + fb_helper->fb = fb; > + drm_setup_crtcs_fb(fb_helper); > + mutex_unlock(&fb_helper->lock); > + > + /* First time setup */ > + if (!fbi->var.bits_per_pixel) { > + struct fb_videomode mode; > + > + drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->format->depth); > + drm_fb_helper_fill_var(fbi, fb_helper, sizes->fb_width, sizes->fb_height); > + > + /* Drop the mode added by register_framebuffer() */ > + fb_destroy_modelist(&fb_helper->fbdev->modelist); > + > + fb_var_to_videomode(&mode, &fbi->var); > + fb_add_videomode(&mode, &fbi->modelist); > + } > + > + return 0; > + > +err_put_dmabuf: > + dma_buf_put(dma_buf); > +err_free_file: > + drm_file_free(file); > + > + return ret; > +} > + > +static void drm_fb_helper_generic_free_buf(struct drm_fb_helper *fb_helper) > +{ > + mutex_lock(&fb_helper->lock); > + fb_helper->fb = NULL; > + drm_setup_crtcs_fb(fb_helper); > + mutex_unlock(&fb_helper->lock); > + > + if (fb_helper->fbdev->fbdefio) { > + cancel_delayed_work_sync(&fb_helper->fbdev->deferred_work); > + cancel_work_sync(&fb_helper->dirty_work); > + fb_deferred_io_cleanup(fb_helper->fbdev); > + } > + > + dma_buf_vunmap(fb_helper->dma_buf, fb_helper->fbdev->screen_buffer); > + dma_buf_put(fb_helper->dma_buf); > + drm_file_free(fb_helper->file); > + > + fb_helper->fbdev->screen_buffer = NULL; > + fb_helper->dma_buf = NULL; > + fb_helper->file = NULL; > +} > + > +static int drm_fb_helper_generic_fb_open(struct fb_info *info, int user) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + int ret; > + > + ret = drm_fb_helper_fb_open(info, user); > + if (ret) > + return ret; > + > + if (!fb_helper->fbdev->screen_buffer) { > + /* > + * Exporting a buffer to get a virtual address results in > + * dma-buf pinning the driver module. This means that we have > + * to defer this to open/close in order to unload the driver > + * module. > + */ > + ret = drm_fb_helper_generic_alloc_buf(fb_helper); > + if (ret) { > + DRM_ERROR("fbdev: Failed to allocate buffer: %d\n", ret); > + drm_fb_helper_fb_release(info, user); > + return ret; > + } > + } > + > + return 0; > +} > + > +static int drm_fb_helper_generic_fb_release(struct fb_info *info, int user) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + > + drm_fb_helper_fb_release(info, user); > + > + if (!atomic_read(&fb_helper->open_count)) > + drm_fb_helper_generic_free_buf(fb_helper); > + > + return 0; > +} > + > +static int drm_fb_helper_generic_fb_mmap(struct fb_info *info, > + struct vm_area_struct *vma) > +{ > + struct drm_fb_helper *fb_helper = info->par; > + > + return dma_buf_mmap(fb_helper->dma_buf, vma, 0); > +} > + > +static struct fb_ops drm_fb_helper_generic_fbdev_ops = { > + .owner = THIS_MODULE, > + DRM_FB_HELPER_DEFAULT_OPS, > + .fb_open = drm_fb_helper_generic_fb_open, > + .fb_release = drm_fb_helper_generic_fb_release, > + .fb_mmap = drm_fb_helper_generic_fb_mmap, > + .fb_read = drm_fb_helper_sys_read, > + .fb_write = drm_fb_helper_sys_write, > + .fb_fillrect = drm_fb_helper_sys_fillrect, > + .fb_copyarea = drm_fb_helper_sys_copyarea, > + .fb_imageblit = drm_fb_helper_sys_imageblit, > +}; > + > +static int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper, > + struct drm_fb_helper_surface_size *sizes) > +{ > + struct fb_ops *fbops; > + struct fb_info *fbi; > + > + DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n", > + sizes->surface_width, sizes->surface_height, > + sizes->surface_bpp); > + > + fb_helper->sizes = *sizes; > + > + /* > + * fb_deferred_io_cleanup() clears &fbops->fb_mmap so a per instance > + * version is necessary. We do it for all users since we don't know > + * yet if the fb has a dirty callback. This also gives us the > + * opportunity to set the correct owner. > + */ > + fbops = kzalloc(sizeof(*fbops), GFP_KERNEL); > + if (!fbops) > + return -ENOMEM; > + > + *fbops = drm_fb_helper_generic_fbdev_ops; > + fbops->owner = fb_helper->dev->driver->fops->owner; > + > + fbi = drm_fb_helper_alloc_fbi(fb_helper); > + if (IS_ERR(fbi)) { > + kfree(fbops); > + return PTR_ERR(fbi); > + } > + > + fbi->par = fb_helper; > + fbi->fbops = fbops; > + strcpy(fbi->fix.id, "generic"); > + > + /* The rest of the setup is deferred to fb_open */ > + > + atomic_set(&fb_helper->open_count, 0); > + > + return 0; > +} > + > +static void drm_fb_helper_generic_release(struct drm_fb_helper *fb_helper) > +{ > + struct fb_ops *fbops = fb_helper->fbdev->fbops; > + > + drm_fb_helper_fini(fb_helper); > + kfree(fb_helper); > + kfree(fbops); > +} > + > +static const struct drm_fb_helper_funcs drm_fb_helper_generic_funcs = { > + .fb_probe = drm_fb_helper_generic_probe, > + .restore = drm_fb_helper_restore_fbdev_mode_unlocked, > + .hotplug_event = drm_fb_helper_hotplug_event, > + .unregister = drm_fb_helper_unregister_fbi, > + .release = drm_fb_helper_generic_release, > +}; > + > +/** > + * drm_fb_helper_generic_fbdev_setup() - Setup generic fbdev emulation > + * @dev: DRM device > + * @preferred_bpp: Preferred bits per pixel for the device. > + * @dev->mode_config.preferred_depth is used if this is zero. > + * @max_conn_count: Maximum number of connectors. > + * @dev->mode_config.num_connector is used if this is zero. > + * > + * This function sets up generic fbdev emulation for drivers that supports > + * dumb buffers which can be exported. The driver doesn't have to do anything > + * else than to call this function, restore, hotplug events and teardown are > + * all taken care of. > + * > + * Returns: > + * Zero on success or negative error code on failure. > + */ > +int drm_fb_helper_generic_fbdev_setup(struct drm_device *dev, > + unsigned int preferred_bpp, > + unsigned int max_conn_count) > +{ > + struct drm_fb_helper *fb_helper; > + int ret; > + > + if (!drm_fbdev_emulation) > + return 0; > + > + fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL); > + if (!fb_helper) > + return -ENOMEM; > + > + ret = drm_fb_helper_fbdev_setup(dev, fb_helper, > + &drm_fb_helper_generic_funcs, > + preferred_bpp, max_conn_count); > + if (ret) { > + kfree(fb_helper); > + return ret; > + } > + > + return 0; > +} > +EXPORT_SYMBOL(drm_fb_helper_generic_fbdev_setup); > + > /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT) > * but the module doesn't depend on any fb console symbols. At least > * attempt to load fbcon to avoid leaving the system without a usable console. > diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h > index 385f967c3552..c6940ab6ffac 100644 > --- a/include/drm/drm_fb_helper.h > +++ b/include/drm/drm_fb_helper.h > @@ -279,6 +279,28 @@ struct drm_fb_helper { > * initial value to 0 themselves. > */ > atomic_t open_count; > + > + /** > + * @file: > + * > + * Optional DRM file. Used by the generic fbdev code. > + */ > + struct drm_file *file; > + > + /** > + * @dma_buf: > + * > + * Optional pointer to a DMA buffer object. > + * Used by the generic fbdev code. > + */ > + struct dma_buf *dma_buf; > + > + /** > + * @sizes: > + * > + * Optional surface sizes. Used by the generic fbdev code. > + */ > + struct drm_fb_helper_surface_size sizes; > }; > > /** > @@ -380,6 +402,10 @@ void drm_fb_helper_fbdev_teardown(struct drm_device *dev); > > void drm_fb_helper_lastclose(struct drm_device *dev); > void drm_fb_helper_output_poll_changed(struct drm_device *dev); > + > +int drm_fb_helper_generic_fbdev_setup(struct drm_device *dev, > + unsigned int preferred_bpp, > + unsigned int max_conn_count); > #else > static inline void drm_fb_helper_prepare(struct drm_device *dev, > struct drm_fb_helper *helper, > @@ -624,6 +650,13 @@ static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev) > { > } > > +static inline int > +drm_fb_helper_generic_fbdev_setup(struct drm_device *dev, > + unsigned int preferred_bpp, > + unsigned int max_conn_count) > +{ > + return 0; > +} > #endif > > static inline int > -- > 2.14.2 >
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index f9dcc7a5761f..270ff6dc8045 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -30,12 +30,15 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/console.h> +#include <linux/dma-buf.h> #include <linux/kernel.h> #include <linux/sysrq.h> #include <linux/slab.h> #include <linux/module.h> #include <drm/drmP.h> +#include <drm/drm_auth.h> #include <drm/drm_crtc.h> +#include <drm/drm_dumb_buffers.h> #include <drm/drm_fb_helper.h> #include <drm/drm_crtc_helper.h> #include <drm/drm_atomic.h> @@ -1951,7 +1954,9 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, if (fb_helper->fbdev->fbops->fb_open == drm_fb_helper_fb_open) atomic_set(&fb_helper->open_count, 0); - strcpy(fb_helper->fb->comm, "[fbcon]"); + if (fb_helper->fb) + strcpy(fb_helper->fb->comm, "[fbcon]"); + return 0; } @@ -2975,6 +2980,300 @@ void drm_fb_helper_output_poll_changed(struct drm_device *dev) } EXPORT_SYMBOL(drm_fb_helper_output_poll_changed); +static struct fb_deferred_io drm_fb_helper_generic_defio = { + .delay = HZ / 20, + .deferred_io = drm_fb_helper_deferred_io, +}; + +static int drm_fb_helper_generic_alloc_buf(struct drm_fb_helper *fb_helper) +{ + struct drm_fb_helper_surface_size *sizes = &fb_helper->sizes; + struct drm_mode_create_dumb dumb_args = { 0 }; + struct drm_prime_handle prime_args = { 0 }; + struct drm_mode_fb_cmd2 fb_args = { 0 }; + struct drm_device *dev = fb_helper->dev; + struct fb_info *fbi = fb_helper->fbdev; + struct drm_framebuffer *fb; + struct dma_buf *dma_buf; + struct drm_file *file; + void *vaddr; + int ret; + + file = drm_file_alloc(dev->primary); + if (IS_ERR(file)) + return PTR_ERR(file); + + drm_dropmaster_ioctl(dev, NULL, file); + + dumb_args.width = sizes->surface_width; + dumb_args.height = sizes->surface_height; + dumb_args.bpp = sizes->surface_bpp; + ret = drm_mode_create_dumb_ioctl(dev, &dumb_args, file); + if (ret) + goto err_free_file; + + fb_args.width = dumb_args.width; + fb_args.height = dumb_args.height; + fb_args.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp, + sizes->surface_depth); + fb_args.handles[0] = dumb_args.handle; + fb_args.pitches[0] = dumb_args.pitch; + ret = drm_mode_addfb2(dev, &fb_args, file); + if (ret) + goto err_free_file; + + fb = drm_framebuffer_lookup(dev, file, fb_args.fb_id); + if (!fb) { + ret = -ENOENT; + goto err_free_file; + } + + /* drop the reference we picked up in framebuffer lookup */ + drm_framebuffer_put(fb); + + strcpy(fb->comm, "[fbcon]"); + + prime_args.handle = dumb_args.handle; + ret = drm_prime_handle_to_fd_ioctl(dev, &prime_args, file); + if (ret) + goto err_free_file; + + dma_buf = dma_buf_get(prime_args.fd); + if (WARN_ON(IS_ERR(dma_buf))) { + ret = PTR_ERR(dma_buf); + goto err_free_file; + } + + vaddr = dma_buf_vmap(dma_buf); + if (!vaddr) { + ret = -ENOMEM; + goto err_put_dmabuf; + } + + if (fb->funcs->dirty) { + fbi->fbdefio = &drm_fb_helper_generic_defio; + fb_deferred_io_init(fbi); + } + + fbi->screen_size = fb->height * fb->pitches[0]; + fbi->fix.smem_len = fbi->screen_size; + fbi->screen_buffer = vaddr; + + fb_helper->dma_buf = dma_buf; + fb_helper->file = file; + + mutex_lock(&fb_helper->lock); + fb_helper->fb = fb; + drm_setup_crtcs_fb(fb_helper); + mutex_unlock(&fb_helper->lock); + + /* First time setup */ + if (!fbi->var.bits_per_pixel) { + struct fb_videomode mode; + + drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->format->depth); + drm_fb_helper_fill_var(fbi, fb_helper, sizes->fb_width, sizes->fb_height); + + /* Drop the mode added by register_framebuffer() */ + fb_destroy_modelist(&fb_helper->fbdev->modelist); + + fb_var_to_videomode(&mode, &fbi->var); + fb_add_videomode(&mode, &fbi->modelist); + } + + return 0; + +err_put_dmabuf: + dma_buf_put(dma_buf); +err_free_file: + drm_file_free(file); + + return ret; +} + +static void drm_fb_helper_generic_free_buf(struct drm_fb_helper *fb_helper) +{ + mutex_lock(&fb_helper->lock); + fb_helper->fb = NULL; + drm_setup_crtcs_fb(fb_helper); + mutex_unlock(&fb_helper->lock); + + if (fb_helper->fbdev->fbdefio) { + cancel_delayed_work_sync(&fb_helper->fbdev->deferred_work); + cancel_work_sync(&fb_helper->dirty_work); + fb_deferred_io_cleanup(fb_helper->fbdev); + } + + dma_buf_vunmap(fb_helper->dma_buf, fb_helper->fbdev->screen_buffer); + dma_buf_put(fb_helper->dma_buf); + drm_file_free(fb_helper->file); + + fb_helper->fbdev->screen_buffer = NULL; + fb_helper->dma_buf = NULL; + fb_helper->file = NULL; +} + +static int drm_fb_helper_generic_fb_open(struct fb_info *info, int user) +{ + struct drm_fb_helper *fb_helper = info->par; + int ret; + + ret = drm_fb_helper_fb_open(info, user); + if (ret) + return ret; + + if (!fb_helper->fbdev->screen_buffer) { + /* + * Exporting a buffer to get a virtual address results in + * dma-buf pinning the driver module. This means that we have + * to defer this to open/close in order to unload the driver + * module. + */ + ret = drm_fb_helper_generic_alloc_buf(fb_helper); + if (ret) { + DRM_ERROR("fbdev: Failed to allocate buffer: %d\n", ret); + drm_fb_helper_fb_release(info, user); + return ret; + } + } + + return 0; +} + +static int drm_fb_helper_generic_fb_release(struct fb_info *info, int user) +{ + struct drm_fb_helper *fb_helper = info->par; + + drm_fb_helper_fb_release(info, user); + + if (!atomic_read(&fb_helper->open_count)) + drm_fb_helper_generic_free_buf(fb_helper); + + return 0; +} + +static int drm_fb_helper_generic_fb_mmap(struct fb_info *info, + struct vm_area_struct *vma) +{ + struct drm_fb_helper *fb_helper = info->par; + + return dma_buf_mmap(fb_helper->dma_buf, vma, 0); +} + +static struct fb_ops drm_fb_helper_generic_fbdev_ops = { + .owner = THIS_MODULE, + DRM_FB_HELPER_DEFAULT_OPS, + .fb_open = drm_fb_helper_generic_fb_open, + .fb_release = drm_fb_helper_generic_fb_release, + .fb_mmap = drm_fb_helper_generic_fb_mmap, + .fb_read = drm_fb_helper_sys_read, + .fb_write = drm_fb_helper_sys_write, + .fb_fillrect = drm_fb_helper_sys_fillrect, + .fb_copyarea = drm_fb_helper_sys_copyarea, + .fb_imageblit = drm_fb_helper_sys_imageblit, +}; + +static int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper, + struct drm_fb_helper_surface_size *sizes) +{ + struct fb_ops *fbops; + struct fb_info *fbi; + + DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n", + sizes->surface_width, sizes->surface_height, + sizes->surface_bpp); + + fb_helper->sizes = *sizes; + + /* + * fb_deferred_io_cleanup() clears &fbops->fb_mmap so a per instance + * version is necessary. We do it for all users since we don't know + * yet if the fb has a dirty callback. This also gives us the + * opportunity to set the correct owner. + */ + fbops = kzalloc(sizeof(*fbops), GFP_KERNEL); + if (!fbops) + return -ENOMEM; + + *fbops = drm_fb_helper_generic_fbdev_ops; + fbops->owner = fb_helper->dev->driver->fops->owner; + + fbi = drm_fb_helper_alloc_fbi(fb_helper); + if (IS_ERR(fbi)) { + kfree(fbops); + return PTR_ERR(fbi); + } + + fbi->par = fb_helper; + fbi->fbops = fbops; + strcpy(fbi->fix.id, "generic"); + + /* The rest of the setup is deferred to fb_open */ + + atomic_set(&fb_helper->open_count, 0); + + return 0; +} + +static void drm_fb_helper_generic_release(struct drm_fb_helper *fb_helper) +{ + struct fb_ops *fbops = fb_helper->fbdev->fbops; + + drm_fb_helper_fini(fb_helper); + kfree(fb_helper); + kfree(fbops); +} + +static const struct drm_fb_helper_funcs drm_fb_helper_generic_funcs = { + .fb_probe = drm_fb_helper_generic_probe, + .restore = drm_fb_helper_restore_fbdev_mode_unlocked, + .hotplug_event = drm_fb_helper_hotplug_event, + .unregister = drm_fb_helper_unregister_fbi, + .release = drm_fb_helper_generic_release, +}; + +/** + * drm_fb_helper_generic_fbdev_setup() - Setup generic fbdev emulation + * @dev: DRM device + * @preferred_bpp: Preferred bits per pixel for the device. + * @dev->mode_config.preferred_depth is used if this is zero. + * @max_conn_count: Maximum number of connectors. + * @dev->mode_config.num_connector is used if this is zero. + * + * This function sets up generic fbdev emulation for drivers that supports + * dumb buffers which can be exported. The driver doesn't have to do anything + * else than to call this function, restore, hotplug events and teardown are + * all taken care of. + * + * Returns: + * Zero on success or negative error code on failure. + */ +int drm_fb_helper_generic_fbdev_setup(struct drm_device *dev, + unsigned int preferred_bpp, + unsigned int max_conn_count) +{ + struct drm_fb_helper *fb_helper; + int ret; + + if (!drm_fbdev_emulation) + return 0; + + fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL); + if (!fb_helper) + return -ENOMEM; + + ret = drm_fb_helper_fbdev_setup(dev, fb_helper, + &drm_fb_helper_generic_funcs, + preferred_bpp, max_conn_count); + if (ret) { + kfree(fb_helper); + return ret; + } + + return 0; +} +EXPORT_SYMBOL(drm_fb_helper_generic_fbdev_setup); + /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT) * but the module doesn't depend on any fb console symbols. At least * attempt to load fbcon to avoid leaving the system without a usable console. diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h index 385f967c3552..c6940ab6ffac 100644 --- a/include/drm/drm_fb_helper.h +++ b/include/drm/drm_fb_helper.h @@ -279,6 +279,28 @@ struct drm_fb_helper { * initial value to 0 themselves. */ atomic_t open_count; + + /** + * @file: + * + * Optional DRM file. Used by the generic fbdev code. + */ + struct drm_file *file; + + /** + * @dma_buf: + * + * Optional pointer to a DMA buffer object. + * Used by the generic fbdev code. + */ + struct dma_buf *dma_buf; + + /** + * @sizes: + * + * Optional surface sizes. Used by the generic fbdev code. + */ + struct drm_fb_helper_surface_size sizes; }; /** @@ -380,6 +402,10 @@ void drm_fb_helper_fbdev_teardown(struct drm_device *dev); void drm_fb_helper_lastclose(struct drm_device *dev); void drm_fb_helper_output_poll_changed(struct drm_device *dev); + +int drm_fb_helper_generic_fbdev_setup(struct drm_device *dev, + unsigned int preferred_bpp, + unsigned int max_conn_count); #else static inline void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper, @@ -624,6 +650,13 @@ static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev) { } +static inline int +drm_fb_helper_generic_fbdev_setup(struct drm_device *dev, + unsigned int preferred_bpp, + unsigned int max_conn_count) +{ + return 0; +} #endif static inline int
Add generic fbdev emulation which uses a drm_file to get a dumb_buffer and drm_framebuffer. The buffer is exported and vmap/mmap called on the dma-buf. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> --- drivers/gpu/drm/drm_fb_helper.c | 301 +++++++++++++++++++++++++++++++++++++++- include/drm/drm_fb_helper.h | 33 +++++ 2 files changed, 333 insertions(+), 1 deletion(-)