From ff590702da3ead33976f3b764de4df78f2aa630a Mon Sep 17 00:00:00 2001 From: Alyssa Rosenzweig Date: Thu, 14 May 2020 13:31:07 -0400 Subject: [PATCH] panfrost: Un/pack UNORM 4 Signed-off-by: Alyssa Rosenzweig Part-of: --- src/panfrost/util/pan_lower_framebuffer.c | 70 +++++++++++++++++++++++ 1 file changed, 70 insertions(+) diff --git a/src/panfrost/util/pan_lower_framebuffer.c b/src/panfrost/util/pan_lower_framebuffer.c index 4d85e8a47ed..e0c00decab5 100644 --- a/src/panfrost/util/pan_lower_framebuffer.c +++ b/src/panfrost/util/pan_lower_framebuffer.c @@ -251,8 +251,72 @@ pan_unpack_unorm_8(nir_builder *b, nir_ssa_def *pack, unsigned num_components) return nir_f2f16(b, unpacked); } +/* UNORM 4 is also unpacked to f16, which prevents us from using the shared + * unpack which strongly assumes fp32. However, on the tilebuffer it is actually packed as: + * + * [AAAA] [0000] [BBBB] [0000] [GGGG] [0000] [RRRR] [0000] + * + * In other words, spacing it out so we're aligned to bytes and on top. So + * pack as: + * + * pack_32_4x8(f2u8_rte(v * 15.0) << 4) + */ + +static nir_ssa_def * +pan_pack_unorm_small(nir_builder *b, nir_ssa_def *v, + nir_ssa_def *scales, nir_ssa_def *shifts) +{ + nir_ssa_def *f = nir_fmul(b, nir_fsat(b, pan_fill_4(b, v)), scales); + nir_ssa_def *u8 = nir_f2u8(b, nir_fround_even(b, f)); + nir_ssa_def *s = nir_ishl(b, u8, shifts); + nir_ssa_def *repl = nir_pack_32_4x8(b, s); + + return pan_replicate_4(b, repl); +} + +static nir_ssa_def * +pan_unpack_unorm_small(nir_builder *b, nir_ssa_def *pack, + nir_ssa_def *scales, nir_ssa_def *shifts) +{ + nir_ssa_def *channels = nir_unpack_32_4x8(b, nir_channel(b, pack, 0)); + nir_ssa_def *raw = nir_ushr(b, nir_u2u16(b, channels), shifts); + return nir_fmul(b, nir_u2f16(b, raw), scales); +} + +static nir_ssa_def * +pan_pack_unorm_4(nir_builder *b, nir_ssa_def *v) +{ + return pan_pack_unorm_small(b, v, + nir_imm_vec4_16(b, 15.0, 15.0, 15.0, 15.0), + nir_imm_ivec4(b, 4, 4, 4, 4)); +} + +static nir_ssa_def * +pan_unpack_unorm_4(nir_builder *b, nir_ssa_def *v) +{ + return pan_unpack_unorm_small(b, v, + nir_imm_vec4_16(b, 1.0 / 15.0, 1.0 / 15.0, 1.0 / 15.0, 1.0 / 15.0), + nir_imm_ivec4(b, 4, 4, 4, 4)); +} + /* Generic dispatches for un/pack regardless of format */ +static bool +pan_is_unorm4(const struct util_format_description *desc) +{ + switch (desc->format) { + case PIPE_FORMAT_B4G4R4A4_UNORM: + case PIPE_FORMAT_B4G4R4X4_UNORM: + case PIPE_FORMAT_A4R4_UNORM: + case PIPE_FORMAT_R4A4_UNORM: + case PIPE_FORMAT_A4B4G4R4_UNORM: + return true; + default: + return false; + } + +} + static nir_ssa_def * pan_unpack(nir_builder *b, const struct util_format_description *desc, @@ -261,6 +325,9 @@ pan_unpack(nir_builder *b, if (util_format_is_unorm8(desc)) return pan_unpack_unorm_8(b, packed, desc->nr_channels); + if (pan_is_unorm4(desc)) + return pan_unpack_unorm_4(b, packed); + if (desc->is_array) { int c = util_format_get_first_non_void_channel(desc->format); assert(c >= 0); @@ -292,6 +359,9 @@ pan_pack(nir_builder *b, if (util_format_is_unorm8(desc)) return pan_pack_unorm_8(b, unpacked); + if (pan_is_unorm4(desc)) + return pan_pack_unorm_4(b, unpacked); + if (desc->is_array) { int c = util_format_get_first_non_void_channel(desc->format); assert(c >= 0); -- 2.30.2