i965: Propagate the GPU reset notifiction strategy down into the driver

If the application requests reset notifiction, connect up the reset
status query method and set gl_context::ResetStrategy.

v2: Update based on kernel interface / libdrm changes.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/mesa/drivers/dri/i965/brw_context.c

@@ -587,11 +587,6 @@ brwCreateContext(gl_api api,
       return false;
    }
 
-   if (notify_reset) {
-      *dri_ctx_error = __DRI_CTX_ERROR_UNKNOWN_ATTRIBUTE;
-      return false;
-   }
-
    struct brw_context *brw = rzalloc(NULL, struct brw_context);
    if (!brw) {
       printf("%s: failed to alloc context\n", __FUNCTION__);
@@ -634,6 +629,9 @@ brwCreateContext(gl_api api,
 
    brw_init_driver_functions(brw, &functions);
 
+   if (notify_reset)
+      functions.GetGraphicsResetStatus = brw_get_graphics_reset_status;
+
    struct gl_context *ctx = &brw->ctx;
 
    if (mesaVis == NULL) {
@@ -675,6 +673,9 @@ brwCreateContext(gl_api api,
    brw_process_intel_debug_variable(brw);
    brw_initialize_context_constants(brw);
 
+   ctx->Const.ResetStrategy = notify_reset
+      ? GL_LOSE_CONTEXT_ON_RESET_ARB : GL_NO_RESET_NOTIFICATION_ARB;
+
    /* Reinitialize the context point state.  It depends on ctx->Const values. */
    _mesa_init_point(ctx);
 
@@ -703,6 +704,21 @@ brwCreateContext(gl_api api,
       }
    }
 
+   /* Notification of GPU resets requires hardware contexts and a kernel new
+    * enough to support DRM_IOCTL_I915_GET_RESET_STATS.
+    */
+   if (notify_reset &&
+       (brw->hw_ctx == NULL
+        || drm_intel_get_reset_stats(brw->hw_ctx, &brw->reset_count, NULL,
+                                     NULL))) {
+      /* This is the wrong error code, but the correct error code (one that
+       * will cause EGL to generate EGL_BAD_MATCH) doesn't seem to exist.
+       */
+      *dri_ctx_error = __DRI_CTX_ERROR_UNKNOWN_ATTRIBUTE;
+      intelDestroyContext(driContextPriv);
+      return false;
+   }
+
    brw_init_surface_formats(brw);
 
    if (brw->is_g4x || brw->gen >= 5) {

src/mesa/drivers/dri/i965/brw_context.h

@@ -1019,6 +1019,14 @@ struct brw_context
 
    drm_intel_context *hw_ctx;
 
+   /**
+    * Number of resets observed in the system at context creation.
+    *
+    * This is tracked in the context so that we can determine that another
+    * reset has occured.
+    */
+   uint32_t reset_count;
+
    struct intel_batchbuffer batch;
    bool no_batch_wrap;