--- /dev/null
+/*
+ * Copyright (C) 2015 Atmel Corporation,
+ * Nicolas Ferre <nicolas.ferre@atmel.com>
+ *
+ * Based on clk-programmable & clk-peripheral drivers by Boris BREZILLON.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pmc.h"
+
+#define PERIPHERAL_MAX 64
+#define PERIPHERAL_ID_MIN 2
+
+#define GENERATED_SOURCE_MAX 6
+#define GENERATED_MAX_DIV 255
+
+struct clk_generated {
+ struct clk_hw hw;
+ struct regmap *regmap;
+ struct clk_range range;
+ spinlock_t *lock;
+ u32 id;
+ u32 gckdiv;
+ u8 parent_id;
+};
+
+#define to_clk_generated(hw) \
+ container_of(hw, struct clk_generated, hw)
+
+static int clk_generated_enable(struct clk_hw *hw)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+ unsigned long flags;
+
+ pr_debug("GCLK: %s, gckdiv = %d, parent id = %d\n",
+ __func__, gck->gckdiv, gck->parent_id);
+
+ spin_lock_irqsave(gck->lock, flags);
+ regmap_write(gck->regmap, AT91_PMC_PCR,
+ (gck->id & AT91_PMC_PCR_PID_MASK));
+ regmap_update_bits(gck->regmap, AT91_PMC_PCR,
+ AT91_PMC_PCR_GCKDIV_MASK | AT91_PMC_PCR_GCKCSS_MASK |
+ AT91_PMC_PCR_CMD | AT91_PMC_PCR_GCKEN,
+ AT91_PMC_PCR_GCKCSS(gck->parent_id) |
+ AT91_PMC_PCR_CMD |
+ AT91_PMC_PCR_GCKDIV(gck->gckdiv) |
+ AT91_PMC_PCR_GCKEN);
+ spin_unlock_irqrestore(gck->lock, flags);
+ return 0;
+}
+
+static void clk_generated_disable(struct clk_hw *hw)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+ unsigned long flags;
+
+ spin_lock_irqsave(gck->lock, flags);
+ regmap_write(gck->regmap, AT91_PMC_PCR,
+ (gck->id & AT91_PMC_PCR_PID_MASK));
+ regmap_update_bits(gck->regmap, AT91_PMC_PCR,
+ AT91_PMC_PCR_CMD | AT91_PMC_PCR_GCKEN,
+ AT91_PMC_PCR_CMD);
+ spin_unlock_irqrestore(gck->lock, flags);
+}
+
+static int clk_generated_is_enabled(struct clk_hw *hw)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+ unsigned long flags;
+ unsigned int status;
+
+ spin_lock_irqsave(gck->lock, flags);
+ regmap_write(gck->regmap, AT91_PMC_PCR,
+ (gck->id & AT91_PMC_PCR_PID_MASK));
+ regmap_read(gck->regmap, AT91_PMC_PCR, &status);
+ spin_unlock_irqrestore(gck->lock, flags);
+
+ return status & AT91_PMC_PCR_GCKEN ? 1 : 0;
+}
+
+static unsigned long
+clk_generated_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+
+ return DIV_ROUND_CLOSEST(parent_rate, gck->gckdiv + 1);
+}
+
+static int clk_generated_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+ struct clk_hw *parent = NULL;
+ long best_rate = -EINVAL;
+ unsigned long tmp_rate, min_rate;
+ int best_diff = -1;
+ int tmp_diff;
+ int i;
+
+ for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
+ u32 div;
+ unsigned long parent_rate;
+
+ parent = clk_hw_get_parent_by_index(hw, i);
+ if (!parent)
+ continue;
+
+ parent_rate = clk_hw_get_rate(parent);
+ min_rate = DIV_ROUND_CLOSEST(parent_rate, GENERATED_MAX_DIV + 1);
+ if (!parent_rate ||
+ (gck->range.max && min_rate > gck->range.max))
+ continue;
+
+ for (div = 1; div < GENERATED_MAX_DIV + 2; div++) {
+ tmp_rate = DIV_ROUND_CLOSEST(parent_rate, div);
+ tmp_diff = abs(req->rate - tmp_rate);
+
+ if (best_diff < 0 || best_diff > tmp_diff) {
+ best_rate = tmp_rate;
+ best_diff = tmp_diff;
+ req->best_parent_rate = parent_rate;
+ req->best_parent_hw = parent;
+ }
+
+ if (!best_diff || tmp_rate < req->rate)
+ break;
+ }
+
+ if (!best_diff)
+ break;
+ }
+
+ pr_debug("GCLK: %s, best_rate = %ld, parent clk: %s @ %ld\n",
+ __func__, best_rate,
+ __clk_get_name((req->best_parent_hw)->clk),
+ req->best_parent_rate);
+
+ if (best_rate < 0)
+ return best_rate;
+
+ req->rate = best_rate;
+ return 0;
+}
+
+/* No modification of hardware as we have the flag CLK_SET_PARENT_GATE set */
+static int clk_generated_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+
+ if (index >= clk_hw_get_num_parents(hw))
+ return -EINVAL;
+
+ gck->parent_id = index;
+ return 0;
+}
+
+static u8 clk_generated_get_parent(struct clk_hw *hw)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+
+ return gck->parent_id;
+}
+
+/* No modification of hardware as we have the flag CLK_SET_RATE_GATE set */
+static int clk_generated_set_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_generated *gck = to_clk_generated(hw);
+ u32 div;
+
+ if (!rate)
+ return -EINVAL;
+
+ if (gck->range.max && rate > gck->range.max)
+ return -EINVAL;
+
+ div = DIV_ROUND_CLOSEST(parent_rate, rate);
+ if (div > GENERATED_MAX_DIV + 1 || !div)
+ return -EINVAL;
+
+ gck->gckdiv = div - 1;
+ return 0;
+}
+
+static const struct clk_ops generated_ops = {
+ .enable = clk_generated_enable,
+ .disable = clk_generated_disable,
+ .is_enabled = clk_generated_is_enabled,
+ .recalc_rate = clk_generated_recalc_rate,
+ .determine_rate = clk_generated_determine_rate,
+ .get_parent = clk_generated_get_parent,
+ .set_parent = clk_generated_set_parent,
+ .set_rate = clk_generated_set_rate,
+};
+
+/**
+ * clk_generated_startup - Initialize a given clock to its default parent and
+ * divisor parameter.
+ *
+ * @gck: Generated clock to set the startup parameters for.
+ *
+ * Take parameters from the hardware and update local clock configuration
+ * accordingly.
+ */
+static void clk_generated_startup(struct clk_generated *gck)
+{
+ u32 tmp;
+ unsigned long flags;
+
+ spin_lock_irqsave(gck->lock, flags);
+ regmap_write(gck->regmap, AT91_PMC_PCR,
+ (gck->id & AT91_PMC_PCR_PID_MASK));
+ regmap_read(gck->regmap, AT91_PMC_PCR, &tmp);
+ spin_unlock_irqrestore(gck->lock, flags);
+
+ gck->parent_id = (tmp & AT91_PMC_PCR_GCKCSS_MASK)
+ >> AT91_PMC_PCR_GCKCSS_OFFSET;
+ gck->gckdiv = (tmp & AT91_PMC_PCR_GCKDIV_MASK)
+ >> AT91_PMC_PCR_GCKDIV_OFFSET;
+}
+
+static struct clk * __init
+at91_clk_register_generated(struct regmap *regmap, spinlock_t *lock, const char
+ *name, const char **parent_names, u8 num_parents,
+ u8 id, const struct clk_range *range)
+{
+ struct clk_generated *gck;
+ struct clk *clk = NULL;
+ struct clk_init_data init;
+
+ gck = kzalloc(sizeof(*gck), GFP_KERNEL);
+ if (!gck)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &generated_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+ gck->id = id;
+ gck->hw.init = &init;
+ gck->regmap = regmap;
+ gck->lock = lock;
+ gck->range = *range;
+
+ clk = clk_register(NULL, &gck->hw);
+ if (IS_ERR(clk))
+ kfree(gck);
+ else
+ clk_generated_startup(gck);
+
+ return clk;
+}
+
+void __init of_sama5d2_clk_generated_setup(struct device_node *np)
+{
+ int num;
+ u32 id;
+ const char *name;
+ struct clk *clk;
+ int num_parents;
+ const char *parent_names[GENERATED_SOURCE_MAX];
+ struct device_node *gcknp;
+ struct clk_range range = CLK_RANGE(0, 0);
+ struct regmap *regmap;
+
+ num_parents = of_clk_get_parent_count(np);
+ if (num_parents <= 0 || num_parents > GENERATED_SOURCE_MAX)
+ return;
+
+ of_clk_parent_fill(np, parent_names, num_parents);
+
+ num = of_get_child_count(np);
+ if (!num || num > PERIPHERAL_MAX)
+ return;
+
+ regmap = syscon_node_to_regmap(of_get_parent(np));
+ if (IS_ERR(regmap))
+ return;
+
+ for_each_child_of_node(np, gcknp) {
+ if (of_property_read_u32(gcknp, "reg", &id))
+ continue;
+
+ if (id < PERIPHERAL_ID_MIN || id >= PERIPHERAL_MAX)
+ continue;
+
+ if (of_property_read_string(np, "clock-output-names", &name))
+ name = gcknp->name;
+
+ of_at91_get_clk_range(gcknp, "atmel,clk-output-range",
+ &range);
+
+ clk = at91_clk_register_generated(regmap, &pmc_pcr_lock, name,
+ parent_names, num_parents,
+ id, &range);
+ if (IS_ERR(clk))
+ continue;
+
+ of_clk_add_provider(gcknp, of_clk_src_simple_get, clk);
+ }
+}
+CLK_OF_DECLARE(of_sama5d2_clk_generated_setup, "atmel,sama5d2-clk-generated",
+ of_sama5d2_clk_generated_setup);
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