drm/i915: Add i915_gem_object_create_from_data()

i915_gem_object_create_from_data() is a generic function to save data
from a plain linear buffer in a new pageable gem object that can later
be accessed by the CPU and/or GPU.

We will need this for the microcontroller firmware loading support code.

Derived from i915_gem_object_write(), originally by Alex Dai

v2:
    Change of function: now allocates & fills a new object, rather than
        writing to an existing object
    New name courtesy of Chris Wilson
    Explicit domain-setting and other improvements per review comments
        by Chris Wilson & Daniel Vetter

v4:
    Rebased

Issue: VIZ-4884
Signed-off-by: Alex Dai <yu.dai@intel.com>
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tom O'Rourke <Tom.O'Rourke@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 23ce125e0298e05b430f05daf45ef56952948fed..77c23796f119986b5b392786f17a3b19b6f315ab 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2758,6 +2758,8 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj,
                         const struct drm_i915_gem_object_ops *ops);
 struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
                                                  size_t size);
+struct drm_i915_gem_object *i915_gem_object_create_from_data(
+               struct drm_device *dev, const void *data, size_t size);
 void i915_init_vm(struct drm_i915_private *dev_priv,
                  struct i915_address_space *vm);
 void i915_gem_free_object(struct drm_gem_object *obj);

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index d9f2701b45932e48c77fe0826158240e53c162ca..322bbefafbc3ae365925a4a4643fa966a82f7d82 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -5477,3 +5477,43 @@ bool i915_gem_obj_is_pinned(struct drm_i915_gem_object *obj)
 
        return false;
 }
+
+/* Allocate a new GEM object and fill it with the supplied data */
+struct drm_i915_gem_object *
+i915_gem_object_create_from_data(struct drm_device *dev,
+                                const void *data, size_t size)
+{
+       struct drm_i915_gem_object *obj;
+       struct sg_table *sg;
+       size_t bytes;
+       int ret;
+
+       obj = i915_gem_alloc_object(dev, round_up(size, PAGE_SIZE));
+       if (IS_ERR_OR_NULL(obj))
+               return obj;
+
+       ret = i915_gem_object_set_to_cpu_domain(obj, true);
+       if (ret)
+               goto fail;
+
+       ret = i915_gem_object_get_pages(obj);
+       if (ret)
+               goto fail;
+
+       i915_gem_object_pin_pages(obj);
+       sg = obj->pages;
+       bytes = sg_copy_from_buffer(sg->sgl, sg->nents, (void *)data, size);
+       i915_gem_object_unpin_pages(obj);
+
+       if (WARN_ON(bytes != size)) {
+               DRM_ERROR("Incomplete copy, wrote %zu of %zu", bytes, size);
+               ret = -EFAULT;
+               goto fail;
+       }
+
+       return obj;
+
+fail:
+       drm_gem_object_unreference(&obj->base);
+       return ERR_PTR(ret);
+}