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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/clk/starfive/clk-starfive-jh71x0.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clk/starfive/clk-starfive-jh71x0.c')
-rw-r--r--drivers/clk/starfive/clk-starfive-jh71x0.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/drivers/clk/starfive/clk-starfive-jh71x0.c b/drivers/clk/starfive/clk-starfive-jh71x0.c
new file mode 100644
index 0000000000..aebc99264a
--- /dev/null
+++ b/drivers/clk/starfive/clk-starfive-jh71x0.c
@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * StarFive JH71X0 Clock Generator Driver
+ *
+ * Copyright (C) 2021-2022 Emil Renner Berthing <kernel@esmil.dk>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/io.h>
+
+#include "clk-starfive-jh71x0.h"
+
+static struct jh71x0_clk *jh71x0_clk_from(struct clk_hw *hw)
+{
+ return container_of(hw, struct jh71x0_clk, hw);
+}
+
+static struct jh71x0_clk_priv *jh71x0_priv_from(struct jh71x0_clk *clk)
+{
+ return container_of(clk, struct jh71x0_clk_priv, reg[clk->idx]);
+}
+
+static u32 jh71x0_clk_reg_get(struct jh71x0_clk *clk)
+{
+ struct jh71x0_clk_priv *priv = jh71x0_priv_from(clk);
+ void __iomem *reg = priv->base + 4 * clk->idx;
+
+ return readl_relaxed(reg);
+}
+
+static void jh71x0_clk_reg_rmw(struct jh71x0_clk *clk, u32 mask, u32 value)
+{
+ struct jh71x0_clk_priv *priv = jh71x0_priv_from(clk);
+ void __iomem *reg = priv->base + 4 * clk->idx;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->rmw_lock, flags);
+ value |= readl_relaxed(reg) & ~mask;
+ writel_relaxed(value, reg);
+ spin_unlock_irqrestore(&priv->rmw_lock, flags);
+}
+
+static int jh71x0_clk_enable(struct clk_hw *hw)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+
+ jh71x0_clk_reg_rmw(clk, JH71X0_CLK_ENABLE, JH71X0_CLK_ENABLE);
+ return 0;
+}
+
+static void jh71x0_clk_disable(struct clk_hw *hw)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+
+ jh71x0_clk_reg_rmw(clk, JH71X0_CLK_ENABLE, 0);
+}
+
+static int jh71x0_clk_is_enabled(struct clk_hw *hw)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+
+ return !!(jh71x0_clk_reg_get(clk) & JH71X0_CLK_ENABLE);
+}
+
+static unsigned long jh71x0_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ u32 div = jh71x0_clk_reg_get(clk) & JH71X0_CLK_DIV_MASK;
+
+ return div ? parent_rate / div : 0;
+}
+
+static int jh71x0_clk_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ unsigned long parent = req->best_parent_rate;
+ unsigned long rate = clamp(req->rate, req->min_rate, req->max_rate);
+ unsigned long div = min_t(unsigned long, DIV_ROUND_UP(parent, rate), clk->max_div);
+ unsigned long result = parent / div;
+
+ /*
+ * we want the result clamped by min_rate and max_rate if possible:
+ * case 1: div hits the max divider value, which means it's less than
+ * parent / rate, so the result is greater than rate and min_rate in
+ * particular. we can't do anything about result > max_rate because the
+ * divider doesn't go any further.
+ * case 2: div = DIV_ROUND_UP(parent, rate) which means the result is
+ * always lower or equal to rate and max_rate. however the result may
+ * turn out lower than min_rate, but then the next higher rate is fine:
+ * div - 1 = ceil(parent / rate) - 1 < parent / rate
+ * and thus
+ * min_rate <= rate < parent / (div - 1)
+ */
+ if (result < req->min_rate && div > 1)
+ result = parent / (div - 1);
+
+ req->rate = result;
+ return 0;
+}
+
+static int jh71x0_clk_set_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ unsigned long div = clamp(DIV_ROUND_CLOSEST(parent_rate, rate),
+ 1UL, (unsigned long)clk->max_div);
+
+ jh71x0_clk_reg_rmw(clk, JH71X0_CLK_DIV_MASK, div);
+ return 0;
+}
+
+static unsigned long jh71x0_clk_frac_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ u32 reg = jh71x0_clk_reg_get(clk);
+ unsigned long div100 = 100 * (reg & JH71X0_CLK_INT_MASK) +
+ ((reg & JH71X0_CLK_FRAC_MASK) >> JH71X0_CLK_FRAC_SHIFT);
+
+ return (div100 >= JH71X0_CLK_FRAC_MIN) ? 100 * parent_rate / div100 : 0;
+}
+
+static int jh71x0_clk_frac_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ unsigned long parent100 = 100 * req->best_parent_rate;
+ unsigned long rate = clamp(req->rate, req->min_rate, req->max_rate);
+ unsigned long div100 = clamp(DIV_ROUND_CLOSEST(parent100, rate),
+ JH71X0_CLK_FRAC_MIN, JH71X0_CLK_FRAC_MAX);
+ unsigned long result = parent100 / div100;
+
+ /* clamp the result as in jh71x0_clk_determine_rate() above */
+ if (result > req->max_rate && div100 < JH71X0_CLK_FRAC_MAX)
+ result = parent100 / (div100 + 1);
+ if (result < req->min_rate && div100 > JH71X0_CLK_FRAC_MIN)
+ result = parent100 / (div100 - 1);
+
+ req->rate = result;
+ return 0;
+}
+
+static int jh71x0_clk_frac_set_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ unsigned long div100 = clamp(DIV_ROUND_CLOSEST(100 * parent_rate, rate),
+ JH71X0_CLK_FRAC_MIN, JH71X0_CLK_FRAC_MAX);
+ u32 value = ((div100 % 100) << JH71X0_CLK_FRAC_SHIFT) | (div100 / 100);
+
+ jh71x0_clk_reg_rmw(clk, JH71X0_CLK_DIV_MASK, value);
+ return 0;
+}
+
+static u8 jh71x0_clk_get_parent(struct clk_hw *hw)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ u32 value = jh71x0_clk_reg_get(clk);
+
+ return (value & JH71X0_CLK_MUX_MASK) >> JH71X0_CLK_MUX_SHIFT;
+}
+
+static int jh71x0_clk_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ u32 value = (u32)index << JH71X0_CLK_MUX_SHIFT;
+
+ jh71x0_clk_reg_rmw(clk, JH71X0_CLK_MUX_MASK, value);
+ return 0;
+}
+
+static int jh71x0_clk_get_phase(struct clk_hw *hw)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ u32 value = jh71x0_clk_reg_get(clk);
+
+ return (value & JH71X0_CLK_INVERT) ? 180 : 0;
+}
+
+static int jh71x0_clk_set_phase(struct clk_hw *hw, int degrees)
+{
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ u32 value;
+
+ if (degrees == 0)
+ value = 0;
+ else if (degrees == 180)
+ value = JH71X0_CLK_INVERT;
+ else
+ return -EINVAL;
+
+ jh71x0_clk_reg_rmw(clk, JH71X0_CLK_INVERT, value);
+ return 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void jh71x0_clk_debug_init(struct clk_hw *hw, struct dentry *dentry)
+{
+ static const struct debugfs_reg32 jh71x0_clk_reg = {
+ .name = "CTRL",
+ .offset = 0,
+ };
+ struct jh71x0_clk *clk = jh71x0_clk_from(hw);
+ struct jh71x0_clk_priv *priv = jh71x0_priv_from(clk);
+ struct debugfs_regset32 *regset;
+
+ regset = devm_kzalloc(priv->dev, sizeof(*regset), GFP_KERNEL);
+ if (!regset)
+ return;
+
+ regset->regs = &jh71x0_clk_reg;
+ regset->nregs = 1;
+ regset->base = priv->base + 4 * clk->idx;
+
+ debugfs_create_regset32("registers", 0400, dentry, regset);
+}
+#else
+#define jh71x0_clk_debug_init NULL
+#endif
+
+static const struct clk_ops jh71x0_clk_gate_ops = {
+ .enable = jh71x0_clk_enable,
+ .disable = jh71x0_clk_disable,
+ .is_enabled = jh71x0_clk_is_enabled,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_div_ops = {
+ .recalc_rate = jh71x0_clk_recalc_rate,
+ .determine_rate = jh71x0_clk_determine_rate,
+ .set_rate = jh71x0_clk_set_rate,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_fdiv_ops = {
+ .recalc_rate = jh71x0_clk_frac_recalc_rate,
+ .determine_rate = jh71x0_clk_frac_determine_rate,
+ .set_rate = jh71x0_clk_frac_set_rate,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_gdiv_ops = {
+ .enable = jh71x0_clk_enable,
+ .disable = jh71x0_clk_disable,
+ .is_enabled = jh71x0_clk_is_enabled,
+ .recalc_rate = jh71x0_clk_recalc_rate,
+ .determine_rate = jh71x0_clk_determine_rate,
+ .set_rate = jh71x0_clk_set_rate,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_mux_ops = {
+ .determine_rate = __clk_mux_determine_rate,
+ .set_parent = jh71x0_clk_set_parent,
+ .get_parent = jh71x0_clk_get_parent,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_gmux_ops = {
+ .enable = jh71x0_clk_enable,
+ .disable = jh71x0_clk_disable,
+ .is_enabled = jh71x0_clk_is_enabled,
+ .determine_rate = __clk_mux_determine_rate,
+ .set_parent = jh71x0_clk_set_parent,
+ .get_parent = jh71x0_clk_get_parent,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_mdiv_ops = {
+ .recalc_rate = jh71x0_clk_recalc_rate,
+ .determine_rate = jh71x0_clk_determine_rate,
+ .get_parent = jh71x0_clk_get_parent,
+ .set_parent = jh71x0_clk_set_parent,
+ .set_rate = jh71x0_clk_set_rate,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_gmd_ops = {
+ .enable = jh71x0_clk_enable,
+ .disable = jh71x0_clk_disable,
+ .is_enabled = jh71x0_clk_is_enabled,
+ .recalc_rate = jh71x0_clk_recalc_rate,
+ .determine_rate = jh71x0_clk_determine_rate,
+ .get_parent = jh71x0_clk_get_parent,
+ .set_parent = jh71x0_clk_set_parent,
+ .set_rate = jh71x0_clk_set_rate,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+static const struct clk_ops jh71x0_clk_inv_ops = {
+ .get_phase = jh71x0_clk_get_phase,
+ .set_phase = jh71x0_clk_set_phase,
+ .debug_init = jh71x0_clk_debug_init,
+};
+
+const struct clk_ops *starfive_jh71x0_clk_ops(u32 max)
+{
+ if (max & JH71X0_CLK_DIV_MASK) {
+ if (max & JH71X0_CLK_MUX_MASK) {
+ if (max & JH71X0_CLK_ENABLE)
+ return &jh71x0_clk_gmd_ops;
+ return &jh71x0_clk_mdiv_ops;
+ }
+ if (max & JH71X0_CLK_ENABLE)
+ return &jh71x0_clk_gdiv_ops;
+ if (max == JH71X0_CLK_FRAC_MAX)
+ return &jh71x0_clk_fdiv_ops;
+ return &jh71x0_clk_div_ops;
+ }
+
+ if (max & JH71X0_CLK_MUX_MASK) {
+ if (max & JH71X0_CLK_ENABLE)
+ return &jh71x0_clk_gmux_ops;
+ return &jh71x0_clk_mux_ops;
+ }
+
+ if (max & JH71X0_CLK_ENABLE)
+ return &jh71x0_clk_gate_ops;
+
+ return &jh71x0_clk_inv_ops;
+}
+EXPORT_SYMBOL_GPL(starfive_jh71x0_clk_ops);