[PATCH v3 11/25] drm/loongson: Compute dumb-buffer sizes with drm_mode_size_dumb()

Thomas Zimmermann
2025-02-18T14:27:08Z

Call drm_mode_size_dumb() to compute dumb-buffer scanline pitch and
buffer size. Align the pitch according to hardware requirements.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Cc: Sui Jingfeng <sui.jingfeng@linux.dev>
---
drivers/gpu/drm/loongson/lsdc_gem.c | 29 ++++++++---------------------
1 file changed, 8 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/loongson/lsdc_gem.c b/drivers/gpu/drm/loongson/lsdc_gem.c
index a720d8f53209..9f982b85301f 100644
--- a/drivers/gpu/drm/loongson/lsdc_gem.c
+++ b/drivers/gpu/drm/loongson/lsdc_gem.c
@@ -6,6 +6,7 @@
#include <linux/dma-buf.h>

#include <drm/drm_debugfs.h>
+#include <drm/drm_dumb_buffers.h>
#include <drm/drm_file.h>
#include <drm/drm_gem.h>
#include <drm/drm_prime.h>
@@ -204,45 +205,31 @@ int lsdc_dumb_create(struct drm_file *file, struct drm_device *ddev,
const struct lsdc_desc *descp = ldev->descp;
u32 domain = LSDC_GEM_DOMAIN_VRAM;
struct drm_gem_object *gobj;
- size_t size;
- u32 pitch;
- u32 handle;
int ret;

- if (!args->width || !args->height)
- return -EINVAL;
-
- if (args->bpp != 32 && args->bpp != 16)
- return -EINVAL;
-
- pitch = args->width * args->bpp / 8;
- pitch = ALIGN(pitch, descp->pitch_align);
- size = pitch * args->height;
- size = ALIGN(size, PAGE_SIZE);
+ ret = drm_mode_size_dumb(ddev, args, descp->pitch_align, 0);
+ if (ret)
+ return ret;

/* Maximum single bo size allowed is the half vram size available */
- if (size > ldev->vram_size / 2) {
- drm_err(ddev, "Requesting(%zuMiB) failed\n", size >> 20);
+ if (args->size > ldev->vram_size / 2) {
+ drm_err(ddev, "Requesting(%zuMiB) failed\n", (size_t)(args->size >> PAGE_SHIFT));
return -ENOMEM;
}

- gobj = lsdc_gem_object_create(ddev, domain, size, false, NULL, NULL);
+ gobj = lsdc_gem_object_create(ddev, domain, args->size, false, NULL, NULL);
if (IS_ERR(gobj)) {
drm_err(ddev, "Failed to create gem object\n");
return PTR_ERR(gobj);
}

- ret = drm_gem_handle_create(file, gobj, &handle);
+ ret = drm_gem_handle_create(file, gobj, &args->handle);

/* drop reference from allocate, handle holds it now */
drm_gem_object_put(gobj);
if (ret)
return ret;

- args->pitch = pitch;
- args->size = size;
- args->handle = handle;
-
return 0;
}