Commit 8538d78e authored by Ville Syrjälä's avatar Ville Syrjälä
Browse files

drm/i915/fbc: Make the cfb allocation loop a bit more legible 



Write the cfb allocation loop as an actual loop instead of some
hard to read goto thing.

Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210610183237.3920-9-ville.syrjala@linux.intel.com


Reviewed-by: default avatarJosé Roberto de Souza <jose.souza@intel.com>
parent c48f67ee

drivers/gpu/drm/i915/display/intel_fbc.c

+26 −25
Original line number Diff line number Diff line
@@ -440,44 +440,45 @@ static u64 intel_fbc_stolen_end(struct drm_i915_private *dev_priv) 
	return min(end, intel_fbc_cfb_base_max(dev_priv));

}



static int intel_fbc_max_limit(struct drm_i915_private *dev_priv, int fb_cpp)

{

	/*

	 * FIXME: FBC1 can have arbitrary cfb stride,

	 * so we could support different compression ratios.

	 */

	if (DISPLAY_VER(dev_priv) < 5 && !IS_G4X(dev_priv))

		return 1;



	/* WaFbcOnly1to1Ratio:ctg */

	if (IS_G4X(dev_priv))

		return 1;



	/* FBC2 can only do 1:1, 1:2, 1:4 */

	return fb_cpp == 2 ? 2 : 4;

}



static int find_compression_limit(struct drm_i915_private *dev_priv,

				  unsigned int size,

				  unsigned int fb_cpp)

{

	struct intel_fbc *fbc = &dev_priv->fbc;

	u64 end = intel_fbc_stolen_end(dev_priv);

	int compression_limit = 1;

	int ret;



	/* HACK: This code depends on what we will do in *_enable_fbc. If that

	 * code changes, this code needs to change as well.

	 *

	 * The enable_fbc code will attempt to use one of our 2 compression

	 * limits, therefore, in that case, we only have 1 resort.

	 */

	int ret, limit = 1;



	/* Try to over-allocate to reduce reallocations and fragmentation. */

	ret = i915_gem_stolen_insert_node_in_range(dev_priv, &fbc->compressed_fb,

						   size <<= 1, 4096, 0, end);

	if (ret == 0)

		return compression_limit;



again:

	/* HW's ability to limit the CFB is 1:4 */

	if (compression_limit > 4 ||

	    (fb_cpp == 2 && compression_limit == 2))

		return 0;

		return limit;



	for (; limit <= intel_fbc_max_limit(dev_priv, fb_cpp); limit <<= 1) {

		ret = i915_gem_stolen_insert_node_in_range(dev_priv, &fbc->compressed_fb,

							   size >>= 1, 4096, 0, end);

	if (ret && DISPLAY_VER(dev_priv) <= 4) {

		return 0;

	} else if (ret) {

		compression_limit <<= 1;

		goto again;

	} else {

		return compression_limit;

		if (ret == 0)

			return limit;

	}



	return 0;

}



static int intel_fbc_alloc_cfb(struct drm_i915_private *dev_priv,