diff options
| -rw-r--r-- | drivers/gpu/drm/ast/ast_main.c | 24 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_gem_vram_helper.c | 61 | ||||
| -rw-r--r-- | include/drm/drm_gem_vram_helper.h | 9 |
3 files changed, 71 insertions, 23 deletions
diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c index b79f484e9bd2..18a0a4ce00f6 100644 --- a/drivers/gpu/drm/ast/ast_main.c +++ b/drivers/gpu/drm/ast/ast_main.c @@ -388,31 +388,9 @@ static int ast_get_dram_info(struct drm_device *dev) return 0; } -enum drm_mode_status ast_mode_config_mode_valid(struct drm_device *dev, - const struct drm_display_mode *mode) -{ - static const unsigned long max_bpp = 4; /* DRM_FORMAT_XRGBA8888 */ - - struct ast_private *ast = dev->dev_private; - unsigned long fbsize, fbpages, max_fbpages; - - /* To support double buffering, a framebuffer may not - * consume more than half of the available VRAM. - */ - max_fbpages = (ast->vram_size / 2) >> PAGE_SHIFT; - - fbsize = mode->hdisplay * mode->vdisplay * max_bpp; - fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE); - - if (fbpages > max_fbpages) - return MODE_MEM; - - return MODE_OK; -} - static const struct drm_mode_config_funcs ast_mode_funcs = { .fb_create = drm_gem_fb_create, - .mode_valid = ast_mode_config_mode_valid, + .mode_valid = drm_vram_helper_mode_valid, .atomic_check = drm_atomic_helper_check, .atomic_commit = drm_atomic_helper_commit, }; diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c index a4863326061a..92a11bb42365 100644 --- a/drivers/gpu/drm/drm_gem_vram_helper.c +++ b/drivers/gpu/drm/drm_gem_vram_helper.c @@ -1141,3 +1141,64 @@ void drm_vram_helper_release_mm(struct drm_device *dev) dev->vram_mm = NULL; } EXPORT_SYMBOL(drm_vram_helper_release_mm); + +/* + * Mode-config helpers + */ + +static enum drm_mode_status +drm_vram_helper_mode_valid_internal(struct drm_device *dev, + const struct drm_display_mode *mode, + unsigned long max_bpp) +{ + struct drm_vram_mm *vmm = dev->vram_mm; + unsigned long fbsize, fbpages, max_fbpages; + + if (WARN_ON(!dev->vram_mm)) + return MODE_BAD; + + max_fbpages = (vmm->vram_size / 2) >> PAGE_SHIFT; + + fbsize = mode->hdisplay * mode->vdisplay * max_bpp; + fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE); + + if (fbpages > max_fbpages) + return MODE_MEM; + + return MODE_OK; +} + +/** + * drm_vram_helper_mode_valid - Tests if a display mode's + * framebuffer fits into the available video memory. + * @dev: the DRM device + * @mode: the mode to test + * + * This function tests if enough video memory is available for using the + * specified display mode. Atomic modesetting requires importing the + * designated framebuffer into video memory before evicting the active + * one. Hence, any framebuffer may consume at most half of the available + * VRAM. Display modes that require a larger framebuffer can not be used, + * even if the CRTC does support them. Each framebuffer is assumed to + * have 32-bit color depth. + * + * Note: + * The function can only test if the display mode is supported in + * general. If there are too many framebuffers pinned to video memory, + * a display mode may still not be usable in practice. The color depth of + * 32-bit fits all current use case. A more flexible test can be added + * when necessary. + * + * Returns: + * MODE_OK if the display mode is supported, or an error code of type + * enum drm_mode_status otherwise. + */ +enum drm_mode_status +drm_vram_helper_mode_valid(struct drm_device *dev, + const struct drm_display_mode *mode) +{ + static const unsigned long max_bpp = 4; /* DRM_FORMAT_XRGB8888 */ + + return drm_vram_helper_mode_valid_internal(dev, mode, max_bpp); +} +EXPORT_SYMBOL(drm_vram_helper_mode_valid); diff --git a/include/drm/drm_gem_vram_helper.h b/include/drm/drm_gem_vram_helper.h index 573e9fd109bf..0f6e47213d8d 100644 --- a/include/drm/drm_gem_vram_helper.h +++ b/include/drm/drm_gem_vram_helper.h @@ -6,6 +6,7 @@ #include <drm/drm_file.h> #include <drm/drm_gem.h> #include <drm/drm_ioctl.h> +#include <drm/drm_modes.h> #include <drm/ttm/ttm_bo_api.h> #include <drm/ttm/ttm_bo_driver.h> #include <drm/ttm/ttm_placement.h> @@ -205,4 +206,12 @@ struct drm_vram_mm *drm_vram_helper_alloc_mm( struct drm_device *dev, uint64_t vram_base, size_t vram_size); void drm_vram_helper_release_mm(struct drm_device *dev); +/* + * Mode-config helpers + */ + +enum drm_mode_status +drm_vram_helper_mode_valid(struct drm_device *dev, + const struct drm_display_mode *mode); + #endif |