On 06/07/15 13:33, Chris Wilson wrote:
Move the query for the TIMESTAMP register from context init to the
screen, so that it is only queried once for all contexts.
On 32bit systems, some old kernels trigger a hw bug resulting in the
TIMESTAMP register being shifted and the low bits always zero. Detect
this by repeating the read a few times and check the register is
incrementing.
You do not do the latter. You only check for the low bits.
I guess the counter is supposed to be monotonically increasing and with
a resolution of a few microseconds which would make this perfectly
valid. Could you confirm and make sure to add this information in the
commit message please?
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk>
---
src/mesa/drivers/dri/i965/intel_extensions.c | 6 +-----
src/mesa/drivers/dri/i965/intel_screen.c | 15 +++++++++++++++
src/mesa/drivers/dri/i965/intel_screen.h | 2 ++
3 files changed, 18 insertions(+), 5 deletions(-)
diff --git a/src/mesa/drivers/dri/i965/intel_extensions.c
b/src/mesa/drivers/dri/i965/intel_extensions.c
index 3423190..740ac81 100644
--- a/src/mesa/drivers/dri/i965/intel_extensions.c
+++ b/src/mesa/drivers/dri/i965/intel_extensions.c
@@ -282,8 +282,6 @@ intelInitExtensions(struct gl_context *ctx)
}
if (brw->gen >= 6) {
- uint64_t dummy;
-
ctx->Extensions.ARB_blend_func_extended =
!driQueryOptionb(&brw->optionCache, "disable_blend_func_extended");
ctx->Extensions.ARB_conditional_render_inverted = true;
@@ -307,9 +305,7 @@ intelInitExtensions(struct gl_context *ctx)
ctx->Extensions.EXT_transform_feedback = true;
ctx->Extensions.OES_depth_texture_cube_map = true;
- /* Test if the kernel has the ioctl. */
- if (drm_intel_reg_read(brw->bufmgr, TIMESTAMP, &dummy) == 0)
- ctx->Extensions.ARB_timer_query = true;
+ ctx->Extensions.ARB_timer_query = brw->intelScreen->hw_has_timestamp;
/* Only enable this in core profile because other parts of Mesa behave
* slightly differently when the extension is enabled.
diff --git a/src/mesa/drivers/dri/i965/intel_screen.c
b/src/mesa/drivers/dri/i965/intel_screen.c
index f9398d7..839a984 100644
--- a/src/mesa/drivers/dri/i965/intel_screen.c
+++ b/src/mesa/drivers/dri/i965/intel_screen.c
@@ -1123,6 +1123,20 @@ intel_detect_swizzling(struct intel_screen *screen)
return true;
}
+static bool
+intel_detect_timestamp(struct intel_screen *screen)
+{
+ uint64_t dummy = 0;
+ int loop = 10;
+
+ do {
+ if (drm_intel_reg_read(screen->bufmgr, TIMESTAMP, &dummy))
+ return false;
+ } while ((dummy & 0xffffffff) == 0 && --loop);
+
+ return loop > 0;
+}
+
/**
* Return array of MSAA modes supported by the hardware. The array is
* zero-terminated and sorted in decreasing order.
@@ -1378,6 +1392,7 @@ __DRIconfig **intelInitScreen2(__DRIscreen *psp)
intelScreen->hw_must_use_separate_stencil = intelScreen->devinfo->gen >= 7;
intelScreen->hw_has_swizzling = intel_detect_swizzling(intelScreen);
+ intelScreen->hw_has_timestamp = intel_detect_timestamp(intelScreen);
const char *force_msaa = getenv("INTEL_FORCE_MSAA");
if (force_msaa) {
diff --git a/src/mesa/drivers/dri/i965/intel_screen.h
b/src/mesa/drivers/dri/i965/intel_screen.h
index 742b3d3..941e0fc 100644
--- a/src/mesa/drivers/dri/i965/intel_screen.h
+++ b/src/mesa/drivers/dri/i965/intel_screen.h
@@ -52,6 +52,8 @@ struct intel_screen
bool hw_has_swizzling;
+ bool hw_has_timestamp;
+
/**
* Does the kernel support context reset notifications?
*/
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/mesa-dev
