Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 186 insertions, 0 deletions

diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c
new file mode 100644
index 000000000..38daf483d
--- /dev/null
+++ b/drivers/clk/tegra/clk-divider.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/clk-provider.h>
+
+#include "clk.h"
+
+#define pll_out_override(p) (BIT((p->shift - 6)))
+#define div_mask(d) ((1 << (d->width)) - 1)
+#define get_mul(d) (1 << d->frac_width)
+#define get_max_div(d) div_mask(d)
+
+#define PERIPH_CLK_UART_DIV_ENB BIT(24)
+
+static int get_div(struct tegra_clk_frac_div *divider, unsigned long rate,
+		   unsigned long parent_rate)
+{
+	int div;
+
+	div = div_frac_get(rate, parent_rate, divider->width,
+			   divider->frac_width, divider->flags);
+
+	if (div < 0)
+		return 0;
+
+	return div;
+}
+
+static unsigned long clk_frac_div_recalc_rate(struct clk_hw *hw,
+					     unsigned long parent_rate)
+{
+	struct tegra_clk_frac_div *divider = to_clk_frac_div(hw);
+	u32 reg;
+	int div, mul;
+	u64 rate = parent_rate;
+
+	reg = readl_relaxed(divider->reg);
+
+	if ((divider->flags & TEGRA_DIVIDER_UART) &&
+	    !(reg & PERIPH_CLK_UART_DIV_ENB))
+		return rate;
+
+	div = (reg >> divider->shift) & div_mask(divider);
+
+	mul = get_mul(divider);
+	div += mul;
+
+	rate *= mul;
+	rate += div - 1;
+	do_div(rate, div);
+
+	return rate;
+}
+
+static long clk_frac_div_round_rate(struct clk_hw *hw, unsigned long rate,
+				   unsigned long *prate)
+{
+	struct tegra_clk_frac_div *divider = to_clk_frac_div(hw);
+	int div, mul;
+	unsigned long output_rate = *prate;
+
+	if (!rate)
+		return output_rate;
+
+	div = get_div(divider, rate, output_rate);
+	if (div < 0)
+		return *prate;
+
+	mul = get_mul(divider);
+
+	return DIV_ROUND_UP(output_rate * mul, div + mul);
+}
+
+static int clk_frac_div_set_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long parent_rate)
+{
+	struct tegra_clk_frac_div *divider = to_clk_frac_div(hw);
+	int div;
+	unsigned long flags = 0;
+	u32 val;
+
+	div = get_div(divider, rate, parent_rate);
+	if (div < 0)
+		return div;
+
+	if (divider->lock)
+		spin_lock_irqsave(divider->lock, flags);
+
+	val = readl_relaxed(divider->reg);
+	val &= ~(div_mask(divider) << divider->shift);
+	val |= div << divider->shift;
+
+	if (divider->flags & TEGRA_DIVIDER_UART) {
+		if (div)
+			val |= PERIPH_CLK_UART_DIV_ENB;
+		else
+			val &= ~PERIPH_CLK_UART_DIV_ENB;
+	}
+
+	if (divider->flags & TEGRA_DIVIDER_FIXED)
+		val |= pll_out_override(divider);
+
+	writel_relaxed(val, divider->reg);
+
+	if (divider->lock)
+		spin_unlock_irqrestore(divider->lock, flags);
+
+	return 0;
+}
+
+static void clk_divider_restore_context(struct clk_hw *hw)
+{
+	struct clk_hw *parent = clk_hw_get_parent(hw);
+	unsigned long parent_rate = clk_hw_get_rate(parent);
+	unsigned long rate = clk_hw_get_rate(hw);
+
+	if (clk_frac_div_set_rate(hw, rate, parent_rate) < 0)
+		WARN_ON(1);
+}
+
+const struct clk_ops tegra_clk_frac_div_ops = {
+	.recalc_rate = clk_frac_div_recalc_rate,
+	.set_rate = clk_frac_div_set_rate,
+	.round_rate = clk_frac_div_round_rate,
+	.restore_context = clk_divider_restore_context,
+};
+
+struct clk *tegra_clk_register_divider(const char *name,
+		const char *parent_name, void __iomem *reg,
+		unsigned long flags, u8 clk_divider_flags, u8 shift, u8 width,
+		u8 frac_width, spinlock_t *lock)
+{
+	struct tegra_clk_frac_div *divider;
+	struct clk *clk;
+	struct clk_init_data init;
+
+	divider = kzalloc(sizeof(*divider), GFP_KERNEL);
+	if (!divider) {
+		pr_err("%s: could not allocate fractional divider clk\n",
+		       __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.ops = &tegra_clk_frac_div_ops;
+	init.flags = flags;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+
+	divider->reg = reg;
+	divider->shift = shift;
+	divider->width = width;
+	divider->frac_width = frac_width;
+	divider->lock = lock;
+	divider->flags = clk_divider_flags;
+
+	/* Data in .init is copied by clk_register(), so stack variable OK */
+	divider->hw.init = &init;
+
+	clk = clk_register(NULL, &divider->hw);
+	if (IS_ERR(clk))
+		kfree(divider);
+
+	return clk;
+}
+
+static const struct clk_div_table mc_div_table[] = {
+	{ .val = 0, .div = 2 },
+	{ .val = 1, .div = 1 },
+	{ .val = 0, .div = 0 },
+};
+
+struct clk *tegra_clk_register_mc(const char *name, const char *parent_name,
+				  void __iomem *reg, spinlock_t *lock)
+{
+	return clk_register_divider_table(NULL, name, parent_name,
+					  CLK_IS_CRITICAL,
+					  reg, 16, 1, CLK_DIVIDER_READ_ONLY,
+					  mc_div_table, lock);
+}