[Intel-gfx] [PATCH 01/15] drm/i915: Add i915_gem_object_write() to i915_gem.c

[Chris Wilson]

On Mon, Jun 15, 2015 at 07:36:19PM +0100, Dave Gordon wrote:
> From: Alex Dai <yu.dai at intel.com>
> 
> i915_gem_object_write() is a generic function to copy data from a plain
> linear buffer to a paged gem object.
> 
> We will need this for the microcontroller firmware loading support code.
> 
> Issue: VIZ-4884
> Signed-off-by: Alex Dai <yu.dai at intel.com>
> Signed-off-by: Dave Gordon <david.s.gordon at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.h |    2 ++
>  drivers/gpu/drm/i915/i915_gem.c |   28 ++++++++++++++++++++++++++++
>  2 files changed, 30 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 611fbd8..9094c06 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -2713,6 +2713,8 @@ void *i915_gem_object_alloc(struct drm_device *dev);
>  void i915_gem_object_free(struct drm_i915_gem_object *obj);
>  void i915_gem_object_init(struct drm_i915_gem_object *obj,
>  			 const struct drm_i915_gem_object_ops *ops);
> +int i915_gem_object_write(struct drm_i915_gem_object *obj,
> +			  const void *data, size_t size);
>  struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
>  						  size_t size);
>  void i915_init_vm(struct drm_i915_private *dev_priv,
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index be35f04..75d63c2 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -5392,3 +5392,31 @@ bool i915_gem_obj_is_pinned(struct drm_i915_gem_object *obj)
>  	return false;
>  }
>  
> +/* Fill the @obj with the @size amount of @data */
> +int i915_gem_object_write(struct drm_i915_gem_object *obj,
> +			const void *data, size_t size)
> +{
> +	struct sg_table *sg;
> +	size_t bytes;
> +	int ret;
> +
> +	ret = i915_gem_object_get_pages(obj);
> +	if (ret)
> +		return ret;
> +
> +	i915_gem_object_pin_pages(obj);

You don't set the object into the CPU domain, or instead manually handle
the domain flushing. You don't handle objects that cannot be written
directly by the CPU, nor do you handle objects whose representation in
memory is not linear.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre