Re: [PATCH 01/13 v4] drm/i915: Add i915_gem_object_create_from_data()

O'Rourke, Tom
2015-07-18T00:40:08Z

On Thu, Jul 09, 2015 at 07:29:02PM +0100, Dave Gordon wrote:
> 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>
> drivers/gpu/drm/i915/i915_drv.h | 2 ++
> drivers/gpu/drm/i915/i915_gem.c | 40 ++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 42 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 464b28d..3c91507 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -2755,6 +2755,8 @@ 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 a0bff41..dbbb649 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -5478,3 +5478,43 @@ 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);
> +}
> --
> 1.9.1