clk: tegra: Add functions for parsing CVB tables

Tegra CVB tables encode the relationship between operating voltage
and optimal frequency as a function of the so-called speedo value.
The speedo value is written to the on-chip fuses at the factory,
which allows the voltage-frequency operating points to be calculated
on an per-chip basis.

Add utility functions to parse the Tegra-specific tables and export the
voltage-frequency pairs to the generic OPP framework for other drivers
to use.

Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/drivers/clk/tegra/cvb.h b/drivers/clk/tegra/cvb.h
new file mode 100644
index 000000000000..f62cdc4f4234
--- /dev/null
+++ b/drivers/clk/tegra/cvb.h
@@ -0,0 +1,67 @@
+/*
+ * Utility functions for parsing Tegra CVB voltage tables
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#ifndef __DRIVERS_CLK_TEGRA_CVB_H
+#define __DRIVERS_CLK_TEGRA_CVB_H
+
+#include <linux/types.h>
+
+struct device;
+
+#define MAX_DVFS_FREQS	40
+
+struct rail_alignment {
+	int offset_uv;
+	int step_uv;
+};
+
+struct cvb_coefficients {
+	int c0;
+	int c1;
+	int c2;
+};
+
+struct cvb_table_freq_entry {
+	unsigned long freq;
+	struct cvb_coefficients coefficients;
+};
+
+struct cvb_cpu_dfll_data {
+	u32 tune0_low;
+	u32 tune0_high;
+	u32 tune1;
+};
+
+struct cvb_table {
+	int speedo_id;
+	int process_id;
+
+	int min_millivolts;
+	int max_millivolts;
+	struct rail_alignment alignment;
+
+	int speedo_scale;
+	int voltage_scale;
+	struct cvb_table_freq_entry cvb_table[MAX_DVFS_FREQS];
+	struct cvb_cpu_dfll_data cpu_dfll_data;
+};
+
+const struct cvb_table *tegra_cvb_build_opp_table(
+		const struct cvb_table *cvb_tables,
+		size_t sz, int process_id,
+		int speedo_id, int speedo_value,
+		unsigned long max_rate,
+		struct device *opp_dev);
+
+#endif