package/mesa3d: allow to enable OpenGL texture float support

While testing on a PC target with an HD6310 graphic card, the
OpenGL support was in "compat profile" mode (i.e OpenGL 2.1).

Extended renderer info (GLX_MESA_query_renderer):
    Vendor: X.Org (0x1002)
    Device: AMD PALM (DRM 2.49.0 / 4.10.4) (0x9802)
    Version: 17.0.2
    Accelerated: yes
    Video memory: 256MB
    Unified memory: no
    Preferred profile: compat (0x2)
    Max core profile version: 0.0
    Max compat profile version: 2.1
    Max GLES1 profile version: 1.1
    Max GLES[23] profile version: 2.0
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD PALM (DRM 2.49.0 / 4.10.4)
OpenGL version string: 2.1 Mesa 17.0.2
OpenGL shading language version string: 1.30

OpenGL ES profile version string: OpenGL ES 2.0 Mesa 17.0.2
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 1.0.16

It turn out that texture float support was missing...

Extended renderer info (GLX_MESA_query_renderer):
    Vendor: X.Org (0x1002)
    Device: AMD PALM (DRM 2.49.0 / 4.10.4) (0x9802)
    Version: 17.0.2
    Accelerated: yes
    Video memory: 256MB
    Unified memory: no
    Preferred profile: core (0x1)
    Max core profile version: 3.3
    Max compat profile version: 3.0
    Max GLES1 profile version: 1.1
    Max GLES[23] profile version: 3.0
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD PALM (DRM 2.49.0 / 4.10.4)
OpenGL core profile version string: 3.3 (Core Profile) Mesa 17.0.2
OpenGL core profile shading language version string: 3.30
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile

OpenGL version string: 3.0 Mesa 17.0.2
OpenGL shading language version string: 1.30
OpenGL context flags: (none)

Add a new option to let the user disable this feature if
it doesn't comply to the SGI license.
Add docs/patents.txt to MESA3D_LICENSE_FILES

Signed-off-by: Romain Naour <romain.naour@gmail.com>
Cc: Bernd Kuhls <bernd.kuhls@t-online.de>
[Thomas:
 - rewrap Config.in help text
 - add note that not all drivers are affected by the texture float
   option.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

2 files changed, 30 insertions, 0 deletions

diff --git a/package/mesa3d/Config.in b/package/mesa3d/Config.in
index 57e88ec66d..099dfd42bd 100644
--- a/package/mesa3d/Config.in
+++ b/package/mesa3d/Config.in
@@ -190,6 +190,29 @@ config BR2_PACKAGE_MESA3D_OPENGL_ES
 	  Use the Khronos OpenGL ES APIs. This is commonly used on embedded
 	  systems and represents a subset of the OpenGL API.
 
+config BR2_PACKAGE_MESA3D_OPENGL_TEXTURE_FLOAT
+	bool "OpenGL texture float (patented format)"
+	help
+	  GL_ARB_texture_float is required to enable GLX core profile
+	  (OpenGL3.x) otherwise the compat profile is used
+	  (OpenGL2.1).
+
+	  The source code to implement ARB_texture_float extension is
+	  included and can be toggled on at compile time, for those
+	  who purchased a license from SGI, or are in a country where
+	  the patent does not apply, etc.
+
+	  Please consult docs/patents.txt with your lawyer before
+	  building Mesa.
+
+	  Also, note that this option doesn't affect all drivers. Some
+	  drivers have support for texture float enabled
+	  unconditionally.
+
+	  If unsure, say N.
+
+	  http://www.google.com/patents/about?id=mIIOAAAAEBAJ&dq=6650327
+
 endif # BR2_PACKAGE_MESA3D_DRIVER
 
 config BR2_PACKAGE_PROVIDES_LIBGL
diff --git a/package/mesa3d/mesa3d.mk b/package/mesa3d/mesa3d.mk
index d2e071528c..ca23f41a2f 100644
--- a/package/mesa3d/mesa3d.mk
+++ b/package/mesa3d/mesa3d.mk
@@ -169,6 +169,13 @@ else
 MESA3D_CONF_OPTS += --disable-gles1 --disable-gles2
 endif
 
+ifeq ($(BR2_PACKAGE_MESA3D_OPENGL_TEXTURE_FLOAT),y)
+MESA3D_CONF_OPTS += --enable-texture-float
+MESA3D_LICENSE_FILES += docs/patents.txt
+else
+MESA3D_CONF_OPTS += --disable-texture-float
+endif
+
 ifeq ($(BR2_PACKAGE_LM_SENSORS),y)
 MESA3D_CONF_OPTS += --enable-lmsensors
 MESA3D_DEPENDENCIES += lm-sensors