On Tue, Mar 4, 2025 at 5:39 PM Thomas Zimmermann <tzimmerm...@suse.de> wrote:
>
> Hi
>
> Am 04.03.25 um 10:19 schrieb Huacai Chen:
> > On Tue, Mar 4, 2025 at 4:41 PM Thomas Zimmermann <tzimmerm...@suse.de>
> > wrote:
> >> Hi
> >>
> >> Am 04.03.25 um 07:33 schrieb Huacai Chen:
> >>> Commit f2fa5a99ca81ce105653 ("drm/ast: Convert ast to SHMEM") converts
> >>> ast from VRAM helper to SHMEM helper. The convertion makesast support
> >>> higher display resolutions, but the performance decreases significantly
> >>> on platforms which don't support writecombine (fallback to uncached).
> >>>
> >>> This patch implements both SHMEM helper and VRAM helper for ast driver
> >>> at the same time. A module parameter ast.shmem is added, 1 means SHMEM
> >>> hepler, 0 means VRAM helper, and the default (-1) means auto selection
> >>> according to drm_arch_can_wc_memory().
> >> Sorry won't happen. There's one memory manager and that's it.
> >>
> >> The question is why there is a difference between the two. Because
> >> conceptually, it's both software rendering that copies the final image
> >> into video ram. Why is that much faster with VRAM helpers?
> > Correct me if I'm wrong.
> >
> > SHMEM helper means "copy damage data to a fixed VRAM buffer", VRAM
> > helper means "double buffers and swapping the two". So if WC is not
> > supported, SHMEM helper is slower from visible effect.
>
> First of all, which component is slow? The kernel console, the desktop,
> something else?
"Slow" here means the desktop ui is not smooth, not kernel console,
and not data copy rate.
>
> On your question. This is all software rendering. In the case of
> GEM-SHMEM, we mmap shmem pages to user-space compositors and let them
> draw the UI. That should be fast because these SHMEM pages should be
> mapped with full caching. The WC caching is the exception here. This
> could be the problem. Maybe these pages are uncached for some reason.
> But so far, we've not touched VRAM at all. After rendering to the
> provided pages, the compositor instructs the DRM driver to flush the
> changes to VRAM. That involves a vmap of the I/O range and a
> memcpy_toio(). Without WC caching, this will be slow. It is optimized by
> using damage information; only the updated part of the screen will be
> copied.
>
> With GEM-VRAM, the kernel mmap's the VRAM's I/O range to the compositor.
> The compositor renders into a malloc'ed memory buffer and then copies
> the result over to the mmap'ed range fom the driver. (And essentially
> into the VRAM). If your platform does not have WC caching, this would be
> uncached and fairly slow. The compositor then instructs the driver to
> swap buffers, which is always fast because we've already done he copying
> in user space.
>
> Now the question is why the GEM-SHMEM code is slower than the GEM-VRAM
> path. In principle, they both do the same work.
Yes, they do the same work, so the data copy rate may be the same. But
GEM-SHMEM is an in-place update while GEM-VRAM is an off-screen
update, so the desktop effect is different.
Huacai
>
> Best regard
> Thomas
>
> >
> >
> > Huacai
> >
> >> Best regards
> >> Thomas
> >>
> >>> Signed-off-by: Huacai Chen <chenhua...@loongson.cn>
> >>> ---
> >>> drivers/gpu/drm/ast/Kconfig | 3 +
> >>> drivers/gpu/drm/ast/ast_drv.c | 31 ++++++++--
> >>> drivers/gpu/drm/ast/ast_drv.h | 6 +-
> >>> drivers/gpu/drm/ast/ast_mm.c | 11 +++-
> >>> drivers/gpu/drm/ast/ast_mode.c | 105 +++++++++++++++++++++++++--------
> >>> 5 files changed, 124 insertions(+), 32 deletions(-)
> >>>
> >>> diff --git a/drivers/gpu/drm/ast/Kconfig b/drivers/gpu/drm/ast/Kconfig
> >>> index da0663542e8a..ed07ef70072f 100644
> >>> --- a/drivers/gpu/drm/ast/Kconfig
> >>> +++ b/drivers/gpu/drm/ast/Kconfig
> >>> @@ -5,6 +5,9 @@ config DRM_AST
> >>> select DRM_CLIENT_SELECTION
> >>> select DRM_GEM_SHMEM_HELPER
> >>> select DRM_KMS_HELPER
> >>> + select DRM_TTM
> >>> + select DRM_TTM_HELPER
> >>> + select DRM_VRAM_HELPER
> >>> select I2C
> >>> select I2C_ALGOBIT
> >>> help
> >>> diff --git a/drivers/gpu/drm/ast/ast_drv.c b/drivers/gpu/drm/ast/ast_drv.c
> >>> index ff3bcdd1cff2..a0c693844f1e 100644
> >>> --- a/drivers/gpu/drm/ast/ast_drv.c
> >>> +++ b/drivers/gpu/drm/ast/ast_drv.c
> >>> @@ -33,9 +33,12 @@
> >>>
> >>> #include <drm/clients/drm_client_setup.h>
> >>> #include <drm/drm_atomic_helper.h>
> >>> +#include <drm/drm_cache.h>
> >>> #include <drm/drm_drv.h>
> >>> #include <drm/drm_fbdev_shmem.h>
> >>> +#include <drm/drm_fbdev_ttm.h>
> >>> #include <drm/drm_gem_shmem_helper.h>
> >>> +#include <drm/drm_gem_vram_helper.h>
> >>> #include <drm/drm_module.h>
> >>> #include <drm/drm_probe_helper.h>
> >>>
> >>> @@ -46,13 +49,18 @@ static int ast_modeset = -1;
> >>> MODULE_PARM_DESC(modeset, "Disable/Enable modesetting");
> >>> module_param_named(modeset, ast_modeset, int, 0400);
> >>>
> >>> +int ast_shmem = -1;
> >>> +
> >>> +MODULE_PARM_DESC(shmem, "1 = SHMEM helper, 0 = VRAM helper, -1 = Auto");
> >>> +module_param_named(shmem, ast_shmem, int, 0400);
> >>> +
> >>> /*
> >>> * DRM driver
> >>> */
> >>>
> >>> DEFINE_DRM_GEM_FOPS(ast_fops);
> >>>
> >>> -static const struct drm_driver ast_driver = {
> >>> +static struct drm_driver ast_driver = {
> >>> .driver_features = DRIVER_ATOMIC |
> >>> DRIVER_GEM |
> >>> DRIVER_MODESET,
> >>> @@ -63,9 +71,6 @@ static const struct drm_driver ast_driver = {
> >>> .major = DRIVER_MAJOR,
> >>> .minor = DRIVER_MINOR,
> >>> .patchlevel = DRIVER_PATCHLEVEL,
> >>> -
> >>> - DRM_GEM_SHMEM_DRIVER_OPS,
> >>> - DRM_FBDEV_SHMEM_DRIVER_OPS,
> >>> };
> >>>
> >>> /*
> >>> @@ -280,6 +285,24 @@ static int ast_pci_probe(struct pci_dev *pdev, const
> >>> struct pci_device_id *ent)
> >>> struct drm_device *drm;
> >>> bool need_post = false;
> >>>
> >>> + if (ast_shmem == -1)
> >>> + ast_shmem = drm_arch_can_wc_memory() ? 1 : 0;
> >>> +
> >>> + if (ast_shmem) {
> >>> + ast_driver.dumb_create = drm_gem_shmem_dumb_create;
> >>> + ast_driver.gem_prime_import_sg_table =
> >>> drm_gem_shmem_prime_import_sg_table;
> >>> +#ifdef CONFIG_DRM_FBDEV_EMULATION
> >>> + ast_driver.fbdev_probe = drm_fbdev_shmem_driver_fbdev_probe;
> >>> +#endif
> >>> + } else {
> >>> + ast_driver.dumb_create = drm_gem_vram_driver_dumb_create;
> >>> + ast_driver.dumb_map_offset = drm_gem_ttm_dumb_map_offset;
> >>> + ast_driver.debugfs_init = drm_vram_mm_debugfs_init;
> >>> +#ifdef CONFIG_DRM_FBDEV_EMULATION
> >>> + ast_driver.fbdev_probe = drm_fbdev_ttm_driver_fbdev_probe;
> >>> +#endif
> >>> + }
> >>> +
> >>> ret = aperture_remove_conflicting_pci_devices(pdev,
> >>> ast_driver.name);
> >>> if (ret)
> >>> return ret;
> >>> diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
> >>> index 6b4305ac07d4..3fcf6717ad8a 100644
> >>> --- a/drivers/gpu/drm/ast/ast_drv.h
> >>> +++ b/drivers/gpu/drm/ast/ast_drv.h
> >>> @@ -29,6 +29,7 @@
> >>> #define __AST_DRV_H__
> >>>
> >>> #include <linux/io.h>
> >>> +#include <linux/iosys-map.h>
> >>> #include <linux/types.h>
> >>>
> >>> #include <drm/drm_connector.h>
> >>> @@ -53,6 +54,8 @@
> >>>
> >>> #define __AST_CHIP(__gen, __index) ((__gen) << 16 | (__index))
> >>>
> >>> +extern int ast_shmem;
> >>> +
> >>> enum ast_chip {
> >>> /* 1st gen */
> >>> AST1000 = __AST_CHIP(1, 0), // unused
> >>> @@ -130,7 +133,8 @@ enum ast_config_mode {
> >>> struct ast_plane {
> >>> struct drm_plane base;
> >>>
> >>> - void __iomem *vaddr;
> >>> + struct drm_gem_vram_object *gbo;
> >>> + struct iosys_map map;
> >>> u64 offset;
> >>> unsigned long size;
> >>> };
> >>> diff --git a/drivers/gpu/drm/ast/ast_mm.c b/drivers/gpu/drm/ast/ast_mm.c
> >>> index 6dfe6d9777d4..588326b7d53e 100644
> >>> --- a/drivers/gpu/drm/ast/ast_mm.c
> >>> +++ b/drivers/gpu/drm/ast/ast_mm.c
> >>> @@ -28,6 +28,7 @@
> >>>
> >>> #include <linux/pci.h>
> >>>
> >>> +#include <drm/drm_gem_vram_helper.h>
> >>> #include <drm/drm_managed.h>
> >>> #include <drm/drm_print.h>
> >>>
> >>> @@ -87,9 +88,13 @@ int ast_mm_init(struct ast_device *ast)
> >>>
> >>> vram_size = ast_get_vram_size(ast);
> >>>
> >>> - ast->vram = devm_ioremap_wc(dev->dev, base, vram_size);
> >>> - if (!ast->vram)
> >>> - return -ENOMEM;
> >>> + if (!ast_shmem)
> >>> + drmm_vram_helper_init(dev, base, vram_size);
> >>> + else {
> >>> + ast->vram = devm_ioremap_wc(dev->dev, base, vram_size);
> >>> + if (!ast->vram)
> >>> + return -ENOMEM;
> >>> + }
> >>>
> >>> ast->vram_base = base;
> >>> ast->vram_size = vram_size;
> >>> diff --git a/drivers/gpu/drm/ast/ast_mode.c
> >>> b/drivers/gpu/drm/ast/ast_mode.c
> >>> index 9d5321c81e68..0744d1ac5dfb 100644
> >>> --- a/drivers/gpu/drm/ast/ast_mode.c
> >>> +++ b/drivers/gpu/drm/ast/ast_mode.c
> >>> @@ -41,6 +41,7 @@
> >>> #include <drm/drm_gem_atomic_helper.h>
> >>> #include <drm/drm_gem_framebuffer_helper.h>
> >>> #include <drm/drm_gem_shmem_helper.h>
> >>> +#include <drm/drm_gem_vram_helper.h>
> >>> #include <drm/drm_managed.h>
> >>> #include <drm/drm_panic.h>
> >>> #include <drm/drm_probe_helper.h>
> >>> @@ -566,8 +567,7 @@ static void ast_wait_for_vretrace(struct ast_device
> >>> *ast)
> >>> */
> >>>
> >>> static int ast_plane_init(struct drm_device *dev, struct ast_plane
> >>> *ast_plane,
> >>> - void __iomem *vaddr, u64 offset, unsigned long
> >>> size,
> >>> - uint32_t possible_crtcs,
> >>> + u64 offset, unsigned long size, uint32_t
> >>> possible_crtcs,
> >>> const struct drm_plane_funcs *funcs,
> >>> const uint32_t *formats, unsigned int
> >>> format_count,
> >>> const uint64_t *format_modifiers,
> >>> @@ -575,7 +575,6 @@ static int ast_plane_init(struct drm_device *dev,
> >>> struct ast_plane *ast_plane,
> >>> {
> >>> struct drm_plane *plane = &ast_plane->base;
> >>>
> >>> - ast_plane->vaddr = vaddr;
> >>> ast_plane->offset = offset;
> >>> ast_plane->size = size;
> >>>
> >>> @@ -630,7 +629,7 @@ static void ast_handle_damage(struct ast_plane
> >>> *ast_plane, struct iosys_map *src
> >>> struct drm_framebuffer *fb,
> >>> const struct drm_rect *clip)
> >>> {
> >>> - struct iosys_map dst = IOSYS_MAP_INIT_VADDR_IOMEM(ast_plane->vaddr);
> >>> + struct iosys_map dst = ast_plane->map;
> >>>
> >>> iosys_map_incr(&dst, drm_fb_clip_offset(fb->pitches[0],
> >>> fb->format, clip));
> >>> drm_fb_memcpy(&dst, fb->pitches, src, fb, clip);
> >>> @@ -650,6 +649,7 @@ static void
> >>> ast_primary_plane_helper_atomic_update(struct drm_plane *plane,
> >>> struct drm_crtc *crtc = plane_state->crtc;
> >>> struct drm_crtc_state *crtc_state =
> >>> drm_atomic_get_new_crtc_state(state, crtc);
> >>> struct drm_rect damage;
> >>> + struct drm_gem_vram_object *gbo;
> >>> struct drm_atomic_helper_damage_iter iter;
> >>>
> >>> if (!old_fb || (fb->format != old_fb->format) ||
> >>> crtc_state->mode_changed) {
> >>> @@ -660,9 +660,15 @@ static void
> >>> ast_primary_plane_helper_atomic_update(struct drm_plane *plane,
> >>> ast_set_vbios_color_reg(ast, fb->format, vbios_mode_info);
> >>> }
> >>>
> >>> - drm_atomic_helper_damage_iter_init(&iter, old_plane_state,
> >>> plane_state);
> >>> - drm_atomic_for_each_plane_damage(&iter, &damage) {
> >>> - ast_handle_damage(ast_plane, shadow_plane_state->data, fb,
> >>> &damage);
> >>> + if (!ast_shmem) {
> >>> + gbo = drm_gem_vram_of_gem(fb->obj[0]);
> >>> + ast_plane->offset = drm_gem_vram_offset(gbo);
> >>> + ast_set_start_address_crt1(ast, (u32)ast_plane->offset);
> >>> + } else {
> >>> + drm_atomic_helper_damage_iter_init(&iter, old_plane_state,
> >>> plane_state);
> >>> + drm_atomic_for_each_plane_damage(&iter, &damage) {
> >>> + ast_handle_damage(ast_plane,
> >>> shadow_plane_state->data, fb, &damage);
> >>> + }
> >>> }
> >>>
> >>> /*
> >>> @@ -704,19 +710,18 @@ static int
> >>> ast_primary_plane_helper_get_scanout_buffer(struct drm_plane *plane,
> >>> {
> >>> struct ast_plane *ast_plane = to_ast_plane(plane);
> >>>
> >>> - if (plane->state && plane->state->fb && ast_plane->vaddr) {
> >>> + if (plane->state && plane->state->fb && ast_plane->map.vaddr_iomem)
> >>> {
> >>> sb->format = plane->state->fb->format;
> >>> sb->width = plane->state->fb->width;
> >>> sb->height = plane->state->fb->height;
> >>> sb->pitch[0] = plane->state->fb->pitches[0];
> >>> - iosys_map_set_vaddr_iomem(&sb->map[0], ast_plane->vaddr);
> >>> + iosys_map_set_vaddr_iomem(&sb->map[0],
> >>> ast_plane->map.vaddr_iomem);
> >>> return 0;
> >>> }
> >>> return -ENODEV;
> >>> }
> >>>
> >>> -static const struct drm_plane_helper_funcs
> >>> ast_primary_plane_helper_funcs = {
> >>> - DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
> >>> +static struct drm_plane_helper_funcs ast_primary_plane_helper_funcs = {
> >>> .atomic_check = ast_primary_plane_helper_atomic_check,
> >>> .atomic_update = ast_primary_plane_helper_atomic_update,
> >>> .atomic_enable = ast_primary_plane_helper_atomic_enable,
> >>> @@ -724,11 +729,10 @@ static const struct drm_plane_helper_funcs
> >>> ast_primary_plane_helper_funcs = {
> >>> .get_scanout_buffer = ast_primary_plane_helper_get_scanout_buffer,
> >>> };
> >>>
> >>> -static const struct drm_plane_funcs ast_primary_plane_funcs = {
> >>> +static struct drm_plane_funcs ast_primary_plane_funcs = {
> >>> .update_plane = drm_atomic_helper_update_plane,
> >>> .disable_plane = drm_atomic_helper_disable_plane,
> >>> .destroy = drm_plane_cleanup,
> >>> - DRM_GEM_SHADOW_PLANE_FUNCS,
> >>> };
> >>>
> >>> static int ast_primary_plane_init(struct ast_device *ast)
> >>> @@ -737,12 +741,28 @@ static int ast_primary_plane_init(struct ast_device
> >>> *ast)
> >>> struct ast_plane *ast_primary_plane = &ast->primary_plane;
> >>> struct drm_plane *primary_plane = &ast_primary_plane->base;
> >>> void __iomem *vaddr = ast->vram;
> >>> - u64 offset = 0; /* with shmem, the primary plane is always at
> >>> offset 0 */
> >>> + u64 offset = 0; /* the primary plane is initially at offset 0 */
> >>> unsigned long cursor_size = roundup(AST_HWC_SIZE +
> >>> AST_HWC_SIGNATURE_SIZE, PAGE_SIZE);
> >>> unsigned long size = ast->vram_fb_available - cursor_size;
> >>> int ret;
> >>>
> >>> - ret = ast_plane_init(dev, ast_primary_plane, vaddr, offset, size,
> >>> + if (ast_shmem) {
> >>> + ast_primary_plane_funcs.reset = drm_gem_reset_shadow_plane;
> >>> + ast_primary_plane_funcs.atomic_duplicate_state =
> >>> drm_gem_duplicate_shadow_plane_state;
> >>> + ast_primary_plane_funcs.atomic_destroy_state =
> >>> drm_gem_destroy_shadow_plane_state;
> >>> + ast_primary_plane_helper_funcs.begin_fb_access =
> >>> drm_gem_begin_shadow_fb_access;
> >>> + ast_primary_plane_helper_funcs.end_fb_access =
> >>> drm_gem_end_shadow_fb_access;
> >>> + } else {
> >>> + ast_primary_plane_funcs.reset =
> >>> drm_atomic_helper_plane_reset;
> >>> + ast_primary_plane_funcs.atomic_duplicate_state =
> >>> drm_atomic_helper_plane_duplicate_state;
> >>> + ast_primary_plane_funcs.atomic_destroy_state =
> >>> drm_atomic_helper_plane_destroy_state;
> >>> + ast_primary_plane_helper_funcs.prepare_fb =
> >>> drm_gem_vram_plane_helper_prepare_fb;
> >>> + ast_primary_plane_helper_funcs.cleanup_fb =
> >>> drm_gem_vram_plane_helper_cleanup_fb;
> >>> + }
> >>> +
> >>> + iosys_map_set_vaddr_iomem(&ast_primary_plane->map, vaddr);
> >>> +
> >>> + ret = ast_plane_init(dev, ast_primary_plane, offset, size,
> >>> 0x01, &ast_primary_plane_funcs,
> >>> ast_primary_plane_formats,
> >>> ARRAY_SIZE(ast_primary_plane_formats),
> >>> NULL, DRM_PLANE_TYPE_PRIMARY);
> >>> @@ -902,10 +922,11 @@ static void
> >>> ast_cursor_plane_helper_atomic_update(struct drm_plane *plane,
> >>> struct drm_plane_state *old_plane_state =
> >>> drm_atomic_get_old_plane_state(state, plane);
> >>> struct ast_device *ast = to_ast_device(plane->dev);
> >>> struct iosys_map src_map = shadow_plane_state->data[0];
> >>> + struct iosys_map dst_map = ast_plane->map;
> >>> struct drm_rect damage;
> >>> const u8 *src = src_map.vaddr; /* TODO: Use mapping abstraction
> >>> properly */
> >>> u64 dst_off = ast_plane->offset;
> >>> - u8 __iomem *dst = ast_plane->vaddr; /* TODO: Use mapping
> >>> abstraction properly */
> >>> + u8 __iomem *dst = dst_map.vaddr_iomem; /* TODO: Use mapping
> >>> abstraction properly */
> >>> u8 __iomem *sig = dst + AST_HWC_SIZE; /* TODO: Use mapping
> >>> abstraction properly */
> >>> unsigned int offset_x, offset_y;
> >>> u16 x, y;
> >>> @@ -967,10 +988,22 @@ static const struct drm_plane_helper_funcs
> >>> ast_cursor_plane_helper_funcs = {
> >>> .atomic_disable = ast_cursor_plane_helper_atomic_disable,
> >>> };
> >>>
> >>> -static const struct drm_plane_funcs ast_cursor_plane_funcs = {
> >>> +static void ast_cursor_plane_destroy(struct drm_plane *plane)
> >>> +{
> >>> + struct ast_plane *ast_plane = to_ast_plane(plane);
> >>> + struct drm_gem_vram_object *gbo = ast_plane->gbo;
> >>> + struct iosys_map map = ast_plane->map;
> >>> +
> >>> + drm_gem_vram_vunmap(gbo, &map);
> >>> + drm_gem_vram_unpin(gbo);
> >>> + drm_gem_vram_put(gbo);
> >>> +
> >>> + drm_plane_cleanup(plane);
> >>> +}
> >>> +
> >>> +static struct drm_plane_funcs ast_cursor_plane_funcs = {
> >>> .update_plane = drm_atomic_helper_update_plane,
> >>> .disable_plane = drm_atomic_helper_disable_plane,
> >>> - .destroy = drm_plane_cleanup,
> >>> DRM_GEM_SHADOW_PLANE_FUNCS,
> >>> };
> >>>
> >>> @@ -979,6 +1012,8 @@ static int ast_cursor_plane_init(struct ast_device
> >>> *ast)
> >>> struct drm_device *dev = &ast->base;
> >>> struct ast_plane *ast_cursor_plane = &ast->cursor_plane;
> >>> struct drm_plane *cursor_plane = &ast_cursor_plane->base;
> >>> + struct drm_gem_vram_object *gbo;
> >>> + struct iosys_map map;
> >>> size_t size;
> >>> void __iomem *vaddr;
> >>> u64 offset;
> >>> @@ -994,10 +1029,25 @@ static int ast_cursor_plane_init(struct ast_device
> >>> *ast)
> >>> if (ast->vram_fb_available < size)
> >>> return -ENOMEM;
> >>>
> >>> - vaddr = ast->vram + ast->vram_fb_available - size;
> >>> - offset = ast->vram_fb_available - size;
> >>> + if (ast_shmem) {
> >>> + vaddr = ast->vram + ast->vram_fb_available - size;
> >>> + offset = ast->vram_fb_available - size;
> >>> + iosys_map_set_vaddr_iomem(&ast_cursor_plane->map, vaddr);
> >>> + ast_cursor_plane_funcs.destroy = drm_plane_cleanup;
> >>> + } else {
> >>> + gbo = drm_gem_vram_create(dev, size, 0);
> >>> + if (IS_ERR(gbo))
> >>> + return PTR_ERR(gbo);
> >>> +
> >>> + drm_gem_vram_pin(gbo, DRM_GEM_VRAM_PL_FLAG_VRAM |
> >>> DRM_GEM_VRAM_PL_FLAG_TOPDOWN);
> >>> + drm_gem_vram_vmap(gbo, &map);
> >>> + offset = drm_gem_vram_offset(gbo);
> >>> + ast_cursor_plane->gbo = gbo;
> >>> + ast_cursor_plane->map = map;
> >>> + ast_cursor_plane_funcs.destroy = ast_cursor_plane_destroy;
> >>> + }
> >>>
> >>> - ret = ast_plane_init(dev, ast_cursor_plane, vaddr, offset, size,
> >>> + ret = ast_plane_init(dev, ast_cursor_plane, offset, size,
> >>> 0x01, &ast_cursor_plane_funcs,
> >>> ast_cursor_plane_formats,
> >>> ARRAY_SIZE(ast_cursor_plane_formats),
> >>> NULL, DRM_PLANE_TYPE_CURSOR);
> >>> @@ -1348,9 +1398,7 @@ static enum drm_mode_status
> >>> ast_mode_config_mode_valid(struct drm_device *dev,
> >>> return MODE_OK;
> >>> }
> >>>
> >>> -static const struct drm_mode_config_funcs ast_mode_config_funcs = {
> >>> - .fb_create = drm_gem_fb_create_with_dirty,
> >>> - .mode_valid = ast_mode_config_mode_valid,
> >>> +static struct drm_mode_config_funcs ast_mode_config_funcs = {
> >>> .atomic_check = drm_atomic_helper_check,
> >>> .atomic_commit = drm_atomic_helper_commit,
> >>> };
> >>> @@ -1372,6 +1420,15 @@ int ast_mode_config_init(struct ast_device *ast)
> >>> dev->mode_config.min_width = 0;
> >>> dev->mode_config.min_height = 0;
> >>> dev->mode_config.preferred_depth = 24;
> >>> + dev->mode_config.prefer_shadow = !ast_shmem;
> >>> +
> >>> + if (!ast_shmem) {
> >>> + ast_mode_config_funcs.fb_create = drm_gem_fb_create;
> >>> + ast_mode_config_funcs.mode_valid =
> >>> drm_vram_helper_mode_valid;
> >>> + } else {
> >>> + ast_mode_config_funcs.fb_create =
> >>> drm_gem_fb_create_with_dirty;
> >>> + ast_mode_config_funcs.mode_valid =
> >>> ast_mode_config_mode_valid;
> >>> + }
> >>>
> >>> if (ast->chip == AST2100 || // GEN2, but not AST1100 (?)
> >>> ast->chip == AST2200 || // GEN3, but not AST2150 (?)
> >> --
> >> --
> >> Thomas Zimmermann
> >> Graphics Driver Developer
> >> SUSE Software Solutions Germany GmbH
> >> Frankenstrasse 146, 90461 Nuernberg, Germany
> >> GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
> >> HRB 36809 (AG Nuernberg)
> >>
>
> --
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Frankenstrasse 146, 90461 Nuernberg, Germany
> GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
> HRB 36809 (AG Nuernberg)
>
