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diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst
index d986e6601e6..49877206fea 100644
--- a/src/gallium/docs/source/tgsi.rst
+++ b/src/gallium/docs/source/tgsi.rst
@@ -1250,6 +1250,110 @@ This opcode is the inverse of :opcode:`DFRACEXP`.
dst.zw = \sqrt{src.zw}
+.. _resourceopcodes:
+
+Resource Access Opcodes
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+Those opcodes follow very closely semantics of the respective Direct3D
+instructions. If in doubt double check Direct3D documentation.
+
+.. opcode:: LOAD - Simplified alternative to the "SAMPLE" instruction.
+ Using the provided integer address, LOAD fetches data
+ from the specified buffer/texture without any filtering.
+ The source data may come from any resource type other
+ than CUBE.
+ LOAD dst, address, resource
+ e.g.
+ LOAD TEMP[0], TEMP[1], RES[0]
+
+.. opcode:: LOAD_MS - Just like LOAD but allows fetch data from
+ multi-sampled surfaces.
+
+.. opcode:: SAMPLE - Using provided address, sample data from the
+ specified texture using the filtering mode identified
+ by the gven sampler. The source data may come from
+ any resource type other than buffers.
+ SAMPLE dst, address, resource, sampler
+ e.g.
+ SAMPLE TEMP[0], TEMP[1], RES[0], SAMP[0]
+
+.. opcode:: SAMPLE_B - Just like the SAMPLE instruction with the
+ exception that an additiona bias is applied to the
+ level of detail computed as part of the instruction
+ execution.
+ SAMPLE_B dst, address, resource, sampler, lod_bias
+ e.g.
+ SAMPLE_B TEMP[0], TEMP[1], RES[0], SAMP[0], TEMP[2].x
+
+.. opcode:: SAMPLE_C - Similar to the SAMPLE instruction but it
+ performs a comparison filter. The operands to SAMPLE_C
+ are identical to SAMPLE, except that tere is an additional
+ float32 operand, reference value, which must be a register
+ with single-component, or a scalar literal.
+ SAMPLE_C makes the hardware use the current samplers
+ compare_func (in pipe_sampler_state) to compare
+ reference value against the red component value for the
+ surce resource at each texel that the currently configured
+ texture filter covers based on the provided coordinates.
+ SAMPLE_C dst, address, resource.r, sampler, ref_value
+ e.g.
+ SAMPLE_C TEMP[0], TEMP[1], RES[0].r, SAMP[0], TEMP[2].x
+
+.. opcode:: SAMPLE_C_LZ - Same as SAMPLE_C, but LOD is 0 and derivatives
+ are ignored. The LZ stands for level-zero.
+ SAMPLE_C_LZ dst, address, resource.r, sampler, ref_value
+ e.g.
+ SAMPLE_C_LZ TEMP[0], TEMP[1], RES[0].r, SAMP[0], TEMP[2].x
+
+
+.. opcode:: SAMPLE_D - SAMPLE_D is identical to the SAMPLE opcode except
+ that the derivatives for the source address in the x
+ direction and the y direction are provided by extra
+ parameters.
+ SAMPLE_D dst, address, resource, sampler, der_x, der_y
+ e.g.
+ SAMPLE_D TEMP[0], TEMP[1], RES[0], SAMP[0], TEMP[2], TEMP[3]
+
+.. opcode:: SAMPLE_L - SAMPLE_L is identical to the SAMPLE opcode except
+ that the LOD is provided directly as a scalar value,
+ representing no anisotropy. Source addresses A channel
+ is used as the LOD.
+ SAMPLE_L dst, address, resource, sampler
+ e.g.
+ SAMPLE_L TEMP[0], TEMP[1], RES[0], SAMP[0]
+
+
+.. opcode:: GATHER4 - Gathers the four texels to be used in a bi-linear
+ filtering operation and packs them into a single register.
+ Only woth with 2D, 2D array, cubemaps, and cubemaps arrays.
+ For 2D textures, only the addressing modes of the sampler and
+ the top level of any mip pyramid are used. Set W to zero.
+ It behaves like the SAMPLE instruction, but a filtered
+ sample is not generated. The four samples that contribute
+ to filtering are places into xyzw in cunter-clockwise order,
+ starting with the (u,v) texture coordinate delta at the
+ following locations (-, +), (+, +), (+, -), (-, -), where
+ the magnitude of the deltas are half a texel.
+
+
+.. opcode:: RESINFO - query the dimentions of a given input buffer.
+ dst receives width, height, depth or array size and
+ total mip count (also can be slected by writemask).
+ RESINFO dst, src_mip_level, resource
+ e.g.
+ RESINFO TEMP[0], TEMP[1].x, RES[0]
+
+.. opcode:: SAMPLE_POS - query the position of a given sample.
+ dst receives float4 (x, y, 0, 0) indicated where the
+ sample is located. If the resource is not a multi-sample
+ resource and not a render target, the result is 0.
+
+.. opcode:: SAMPLE_INFO - dst receives number of components in x.
+ If the resource is not a multi-sample resource and
+ not a render target, the result is 0.
+
+
Explanation of symbols used
------------------------------
@@ -1332,6 +1436,8 @@ wrapping when interpolating by the rasteriser. If TGSI_CYLINDRICAL_WRAP_X
is set to 1, the X component should be interpolated according to cylindrical
wrapping rules.
+If file is TGSI_FILE_RESOURCE, a Declaration Resource token follows.
+
Declaration Semantic
^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1475,6 +1581,23 @@ is a writable stencil reference value. Only the Y component is writable.
This allows the fragment shader to change the fragments stencilref value.
+Declaration Resource
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+ Follows Declaration token if file is TGSI_FILE_RESOURCE.
+
+ DCL RES[#], resource, type(s)
+
+ Declares a shader input resource and assigns it to a RES[#]
+ register.
+
+ resource can be one of BUFFER, 1D, 2D, 3D, CUBE, 1DArray and
+ 2DArray.
+
+ type must be 1 or 4 entries (if specifying on a per-component
+ level) out of UNORM, SNORM, SINT, UINT and FLOAT.
+
+
Properties
^^^^^^^^^^^^^^^^^^^^^^^^