i965: Query and store GPU properties from kernel

Certain products are not uniquely identifiable based on device id alone. The
kernel exports an interface to help deal with this. This patch merely introduces
the consumer of the interface and makes sure nothing breaks.

It is also possible to use these values for programming GPGPU mode, and I plan
to do that as well.

The interface was introduced in libdrm 2.4.60, which is already required, so it
should all be fine.

v2: Some minor changes recommended by Matt

Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

diff --git a/src/mesa/drivers/dri/i965/intel_screen.c b/src/mesa/drivers/dri/i965/intel_screen.c
index ee7c1d7bc2ca74bc0be02ecc9afe041c9f1213ec..64b8524c64bbeac8eabea75e6c01e239e5a51bcb 100644 (file)
--- a/src/mesa/drivers/dri/i965/intel_screen.c
+++ b/src/mesa/drivers/dri/i965/intel_screen.c
@@ -1082,6 +1082,7 @@ static bool
 intel_init_bufmgr(struct intel_screen *intelScreen)
 {
    __DRIscreen *spriv = intelScreen->driScrnPriv;
+   bool devid_override = getenv("INTEL_DEVID_OVERRIDE") != NULL;
 
    intelScreen->no_hw = getenv("INTEL_NO_HW") != NULL;
 
@@ -1099,6 +1100,25 @@ intel_init_bufmgr(struct intel_screen *intelScreen)
       return false;
    }
 
+   intelScreen->subslice_total = -1;
+   intelScreen->eu_total = -1;
+
+   /* Everything below this is for real hardware only */
+   if (intelScreen->no_hw || devid_override)
+      return true;
+
+   intel_get_param(spriv, I915_PARAM_SUBSLICE_TOTAL,
+                   &intelScreen->subslice_total);
+   intel_get_param(spriv, I915_PARAM_EU_TOTAL, &intelScreen->eu_total);
+
+   /* Without this information, we cannot get the right Braswell brandstrings,
+    * and we have to use conservative numbers for GPGPU on many platforms, but
+    * otherwise, things will just work.
+    */
+   if (intelScreen->subslice_total == -1 || intelScreen->eu_total == -1)
+      _mesa_warning(NULL,
+                    "Kernel 4.1 required to properly query GPU properties.\n");
+
    return true;
 }
 

diff --git a/src/mesa/drivers/dri/i965/intel_screen.h b/src/mesa/drivers/dri/i965/intel_screen.h
index 3a5f22c3a6796f474c410e5d65eeeb26d78e90f3..01d45d0c0166afdf0e2f4004754c99d53f44f7fe 100644 (file)
--- a/src/mesa/drivers/dri/i965/intel_screen.h
+++ b/src/mesa/drivers/dri/i965/intel_screen.h
@@ -81,7 +81,17 @@ struct intel_screen
     * I915_PARAM_CMD_PARSER_VERSION parameter
     */
    int cmd_parser_version;
- };
+
+   /**
+    * Number of subslices reported by the I915_PARAM_SUBSLICE_TOTAL parameter
+    */
+   int subslice_total;
+
+   /**
+    * Number of EUs reported by the I915_PARAM_EU_TOTAL parameter
+    */
+   int eu_total;
+};
 
 extern void intelDestroyContext(__DRIcontext * driContextPriv);