[PATCH v3 2/2] etnaviv: Add support for ETC2 texture compression

[laanwj at gmail.com]

From: "Wladimir J. van der Laan" <laanwj at gmail.com>

Add support for ETC2 compressed textures in the etnaviv driver.

One step closer towards GL ES 3 support.

For now, treat SRGB and RGB formats the same. It looks like these are
distinguished using a different bit in sampler state, and not part of
the format, but I have not yet been able to confirm this for sure.

(Only enabled on GC3000+ for now, as the GC2000 ETC2 decoder
implementation is buggy and we don't work around that)

Signed-off-by: Wladimir J. van der Laan <laanwj at gmail.com>
---
 src/gallium/drivers/etnaviv/etnaviv_format.c | 11 +++++++++++
 src/gallium/drivers/etnaviv/etnaviv_screen.c | 12 +++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/gallium/drivers/etnaviv/etnaviv_format.c b/src/gallium/drivers/etnaviv/etnaviv_format.c
index 354dc20..492499a 100644
--- a/src/gallium/drivers/etnaviv/etnaviv_format.c
+++ b/src/gallium/drivers/etnaviv/etnaviv_format.c
@@ -233,6 +233,17 @@ static struct etna_format formats[PIPE_FORMAT_COUNT] = {
    _T(DXT3_RGBA, DXT2_DXT3, SWIZ(X, Y, Z, W), NONE),
    _T(DXT5_RGBA, DXT4_DXT5, SWIZ(X, Y, Z, W), NONE),
 
+   _T(ETC2_RGB8,       EXT_NONE | EXT_FORMAT,                          SWIZ(X, Y, Z, W), NONE), /* Extd. format NONE doubles as ETC2_RGB8 */
+   _T(ETC2_SRGB8,      EXT_NONE | EXT_FORMAT,                          SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_RGB8A1,     EXT_RGB8_PUNCHTHROUGH_ALPHA1_ETC2 | EXT_FORMAT, SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_SRGB8A1,    EXT_RGB8_PUNCHTHROUGH_ALPHA1_ETC2 | EXT_FORMAT, SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_RGBA8,      EXT_RGBA8_ETC2_EAC | EXT_FORMAT,                SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_SRGBA8,     EXT_RGBA8_ETC2_EAC | EXT_FORMAT,                SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_R11_UNORM,  EXT_R11_EAC | EXT_FORMAT,                       SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_R11_SNORM,  EXT_SIGNED_R11_EAC | EXT_FORMAT,                SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_RG11_UNORM, EXT_RG11_EAC | EXT_FORMAT,                      SWIZ(X, Y, Z, W), NONE),
+   _T(ETC2_RG11_SNORM, EXT_SIGNED_RG11_EAC | EXT_FORMAT,               SWIZ(X, Y, Z, W), NONE),
+
    /* YUV */
    _T(YUYV, YUY2, SWIZ(X, Y, Z, W), YUY2),
    _T(UYVY, UYVY, SWIZ(X, Y, Z, W), NONE),
diff --git a/src/gallium/drivers/etnaviv/etnaviv_screen.c b/src/gallium/drivers/etnaviv/etnaviv_screen.c
index 96f9a8e..5dc436d 100644
--- a/src/gallium/drivers/etnaviv/etnaviv_screen.c
+++ b/src/gallium/drivers/etnaviv/etnaviv_screen.c
@@ -471,9 +471,19 @@ gpu_supports_texure_format(struct etna_screen *screen, uint32_t fmt,
    if (fmt >= TEXTURE_FORMAT_DXT1 && fmt <= TEXTURE_FORMAT_DXT4_DXT5)
       supported = VIV_FEATURE(screen, chipFeatures, DXT_TEXTURE_COMPRESSION);
 
-   if (fmt & EXT_FORMAT)
+   if (fmt & EXT_FORMAT) {
       supported = VIV_FEATURE(screen, chipMinorFeatures1, HALTI0);
 
+      /* ETC1 is checked above, as it has its own feature bit. ETC2 is
+       * supported with HALTI0, however that implementation is buggy in hardware.
+       * The blob driver does per-block patching to work around this. As this
+       * is currently not implemented by etnaviv, enable it for HALTI1 (GC3000)
+       * only.
+       */
+      if (util_format_is_etc(format))
+         supported = VIV_FEATURE(screen, chipMinorFeatures2, HALTI1);
+   }
+
    if (!supported)
       return false;
 
-- 
2.7.4