drm/radeon: add a asic callback to get the xclk
This is required to get the reference clock used
by the gfx engine for things like timestamps. Fixes
support for GL extensions the use timestamps on
certain boards.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 719f03e..b5064fa 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -70,6 +70,33 @@
extern void evergreen_print_gpu_status_regs(struct radeon_device *rdev);
extern bool evergreen_is_display_hung(struct radeon_device *rdev);
+#define PCIE_BUS_CLK 10000
+#define TCLK (PCIE_BUS_CLK / 10)
+
+/**
+ * si_get_xclk - get the xclk
+ *
+ * @rdev: radeon_device pointer
+ *
+ * Returns the reference clock used by the gfx engine
+ * (SI).
+ */
+u32 si_get_xclk(struct radeon_device *rdev)
+{
+ u32 reference_clock = rdev->clock.spll.reference_freq;
+ u32 tmp;
+
+ tmp = RREG32(CG_CLKPIN_CNTL_2);
+ if (tmp & MUX_TCLK_TO_XCLK)
+ return TCLK;
+
+ tmp = RREG32(CG_CLKPIN_CNTL);
+ if (tmp & XTALIN_DIVIDE)
+ return reference_clock / 4;
+
+ return reference_clock;
+}
+
/* get temperature in millidegrees */
int si_get_temp(struct radeon_device *rdev)
{