clk: tegra: Add DFLL DVCO reset control for Tegra124

The DVCO present in the DFLL IP block has a separate reset line,
exposed via the CAR IP block.  This reset line is asserted upon SoC
reset.  Unless something (such as the DFLL driver) deasserts this
line, the DVCO will not oscillate, although reads and writes to the
DFLL IP block will complete.

Thanks to Aleksandr Frid <afrid@nvidia.com> for identifying this and
saving hours of debugging time.

Signed-off-by: Paul Walmsley <pwalmsley@nvidia.com>
[ttynkkynen: ported to tegra124 from tegra114]
Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
[mikko.perttunen: ported to special reset callback]
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Acked-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/include/dt-bindings/reset/tegra124-car.h b/include/dt-bindings/reset/tegra124-car.h
new file mode 100644
index 0000000..070e4f6
--- /dev/null
+++ b/include/dt-bindings/reset/tegra124-car.h
@@ -0,0 +1,12 @@
+/*
+ * This header provides Tegra124-specific constants for binding
+ * nvidia,tegra124-car.
+ */
+
+#ifndef _DT_BINDINGS_RESET_TEGRA124_CAR_H
+#define _DT_BINDINGS_RESET_TEGRA124_CAR_H
+
+#define TEGRA124_RESET(x)		(6 * 32 + (x))
+#define TEGRA124_RST_DFLL_DVCO		TEGRA124_RESET(0)
+
+#endif	/* _DT_BINDINGS_RESET_TEGRA124_CAR_H */