Correct x/y/pitch limitations in several cases, and detail them in i830_exa.c.

This reduces max framebuffer width and increases max framebuffer height on
965, reduces max X/Y on pre-965 EXA (could have caused mis-rendering), and
increases max X/Y on 965 EXA (would have prevented acceleration).

2 files changed, 54 insertions, 15 deletions

diff --git a/src/i830_driver.c b/src/i830_driver.c
index 9bc74b54..20781aa0 100644
--- a/src/i830_driver.c
+++ b/src/i830_driver.c
@@ -1139,14 +1139,13 @@ I830PreInit(ScrnInfoPtr pScrn, int flags)
    /* Allocate an xf86CrtcConfig */
    xf86CrtcConfigInit (pScrn);
    xf86_config = XF86_CRTC_CONFIG_PTR(pScrn);
-   
-   if (IS_I965G(pI830))
-   {
-      max_width = 16384;
-      max_height = 4096;
-   }
-   else
-   {
+
+   /* See i830_exa.c comments for why we limit the framebuffer size like this.
+    */
+   if (IS_I965G(pI830)) {
+      max_width = 8192;
+      max_height = 8192;
+   } else {
       max_width = 2048;
       max_height = 2048;
    }
diff --git a/src/i830_exa.c b/src/i830_exa.c
index 4944e409..f11424f2 100644
--- a/src/i830_exa.c
+++ b/src/i830_exa.c
@@ -447,13 +447,53 @@ I830EXAInit(ScreenPtr pScreen)
 	/* disable Xv here... */
     }
 
-    /* i915 3D requires 16 byte alignment (4k if tiled) */
-    pI830->EXADriverPtr->pixmapOffsetAlign = 256;
-    pI830->EXADriverPtr->pixmapPitchAlign = 64;
-
-    /* i845 and i945 2D limits rendering to 65536 lines and pitch of 32768. */
-    pI830->EXADriverPtr->maxX = 4095;
-    pI830->EXADriverPtr->maxY = 4095;
+    /* Limits are described in the BLT engine chapter under Graphics Data Size
+     * Limitations, and the descriptions of SURFACE_STATE, 3DSTATE_BUFFER_INFO,
+     * 3DSTATE_DRAWING_RECTANGLE, 3DSTATE_MAP_INFO, and 3DSTATE_MAP_INFO.
+     *
+     * i845 through i965 limits 2D rendering to 65536 lines and pitch of 32768.
+     *
+     * i965 limits 3D surface to (2*element size)-aligned offset if un-tiled.
+     * i965 limits 3D surface to 4kB-aligned offset if tiled.
+     * i965 limits 3D surfaces to w,h of ?,8192.
+     * i965 limits 3D surface to pitch of 1B - 128kB.
+     * i965 limits 3D surface pitch alignment to 512B, only if tiled.
+     * i965 limits 3D destination drawing rect to w,h of 8192,8192.
+     *
+     * i915 limits 3D textures to 4B-aligned offset if un-tiled.
+     * i915 limits 3D textures to ~4kB-aligned offset if tiled.
+     * i915 limits 3D textures to width,height of 2048,2048.
+     * i915 limits 3D textures to pitch of 16B - 8kB, in dwords.
+     * i915 limits 3D destination to ~4kB-aligned offset if tiled.
+     * i915 limits 3D destination to pitch of 16B - 8kB, in dwords, if un-tiled.
+     * i915 limits 3D destination to pitch of 512B - 8kB, in tiles, if tiled.
+     * i915 limits 3D destination to POT aligned pitch if tiled.
+     * i915 limits 3D destination drawing rect to w,h of 2048,2048.
+     *
+     * i845 limits 3D textures to 4B-aligned offset if un-tiled.
+     * i845 limits 3D textures to ~4kB-aligned offset if tiled.
+     * i845 limits 3D textures to width,height of 2048,2048.
+     * i845 limits 3D textures to pitch of 4B - 8kB, in dwords.
+     * i845 limits 3D destination to 4B-aligned offset if un-tiled.
+     * i845 limits 3D destination to ~4kB-aligned offset if tiled.
+     * i845 limits 3D destination to pitch of 8B - 8kB, in dwords.
+     * i845 limits 3D destination drawing rect to w,h of 2048,2048.
+     *
+     * For the tiled issues, the only tiled buffer we draw to should be
+     * the front, which will have an appropriate pitch/offset already set up,
+     * so EXA doesn't need to worry.
+     */
+    if (IS_I965G(pI830)) {
+	pI830->EXADriverPtr->pixmapOffsetAlign = 4 * 2;
+	pI830->EXADriverPtr->pixmapPitchAlign = 1;
+	pI830->EXADriverPtr->maxX = 8192;
+	pI830->EXADriverPtr->maxY = 8192;
+    } else {
+	pI830->EXADriverPtr->pixmapOffsetAlign = 4;
+	pI830->EXADriverPtr->pixmapPitchAlign = 16;
+	pI830->EXADriverPtr->maxX = 2048;
+	pI830->EXADriverPtr->maxY = 2048;
+    }
 
     /* Sync */
     pI830->EXADriverPtr->WaitMarker = I830EXASync;