1 files changed, 467 insertions, 0 deletions

diff --git a/drivers/clk/at91/clk-peripheral.c b/drivers/clk/at91/clk-peripheral.c
new file mode 100644
index 000000000..7a27ba8e0
--- /dev/null
+++ b/drivers/clk/at91/clk-peripheral.c
@@ -0,0 +1,467 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ */
+
+#include <linux/bitops.h>
+#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_SPINLOCK(pmc_pcr_lock);
+
+#define PERIPHERAL_ID_MIN	2
+#define PERIPHERAL_ID_MAX	31
+#define PERIPHERAL_MASK(id)	(1 << ((id) & PERIPHERAL_ID_MAX))
+
+#define PERIPHERAL_MAX_SHIFT	3
+
+struct clk_peripheral {
+	struct clk_hw hw;
+	struct regmap *regmap;
+	u32 id;
+};
+
+#define to_clk_peripheral(hw) container_of(hw, struct clk_peripheral, hw)
+
+struct clk_sam9x5_peripheral {
+	struct clk_hw hw;
+	struct regmap *regmap;
+	struct clk_range range;
+	spinlock_t *lock;
+	u32 id;
+	u32 div;
+	const struct clk_pcr_layout *layout;
+	bool auto_div;
+	int chg_pid;
+};
+
+#define to_clk_sam9x5_peripheral(hw) \
+	container_of(hw, struct clk_sam9x5_peripheral, hw)
+
+static int clk_peripheral_enable(struct clk_hw *hw)
+{
+	struct clk_peripheral *periph = to_clk_peripheral(hw);
+	int offset = AT91_PMC_PCER;
+	u32 id = periph->id;
+
+	if (id < PERIPHERAL_ID_MIN)
+		return 0;
+	if (id > PERIPHERAL_ID_MAX)
+		offset = AT91_PMC_PCER1;
+	regmap_write(periph->regmap, offset, PERIPHERAL_MASK(id));
+
+	return 0;
+}
+
+static void clk_peripheral_disable(struct clk_hw *hw)
+{
+	struct clk_peripheral *periph = to_clk_peripheral(hw);
+	int offset = AT91_PMC_PCDR;
+	u32 id = periph->id;
+
+	if (id < PERIPHERAL_ID_MIN)
+		return;
+	if (id > PERIPHERAL_ID_MAX)
+		offset = AT91_PMC_PCDR1;
+	regmap_write(periph->regmap, offset, PERIPHERAL_MASK(id));
+}
+
+static int clk_peripheral_is_enabled(struct clk_hw *hw)
+{
+	struct clk_peripheral *periph = to_clk_peripheral(hw);
+	int offset = AT91_PMC_PCSR;
+	unsigned int status;
+	u32 id = periph->id;
+
+	if (id < PERIPHERAL_ID_MIN)
+		return 1;
+	if (id > PERIPHERAL_ID_MAX)
+		offset = AT91_PMC_PCSR1;
+	regmap_read(periph->regmap, offset, &status);
+
+	return status & PERIPHERAL_MASK(id) ? 1 : 0;
+}
+
+static const struct clk_ops peripheral_ops = {
+	.enable = clk_peripheral_enable,
+	.disable = clk_peripheral_disable,
+	.is_enabled = clk_peripheral_is_enabled,
+};
+
+struct clk_hw * __init
+at91_clk_register_peripheral(struct regmap *regmap, const char *name,
+			     const char *parent_name, u32 id)
+{
+	struct clk_peripheral *periph;
+	struct clk_init_data init;
+	struct clk_hw *hw;
+	int ret;
+
+	if (!name || !parent_name || id > PERIPHERAL_ID_MAX)
+		return ERR_PTR(-EINVAL);
+
+	periph = kzalloc(sizeof(*periph), GFP_KERNEL);
+	if (!periph)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &peripheral_ops;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+	init.flags = 0;
+
+	periph->id = id;
+	periph->hw.init = &init;
+	periph->regmap = regmap;
+
+	hw = &periph->hw;
+	ret = clk_hw_register(NULL, &periph->hw);
+	if (ret) {
+		kfree(periph);
+		hw = ERR_PTR(ret);
+	}
+
+	return hw;
+}
+
+static void clk_sam9x5_peripheral_autodiv(struct clk_sam9x5_peripheral *periph)
+{
+	struct clk_hw *parent;
+	unsigned long parent_rate;
+	int shift = 0;
+
+	if (!periph->auto_div)
+		return;
+
+	if (periph->range.max) {
+		parent = clk_hw_get_parent_by_index(&periph->hw, 0);
+		parent_rate = clk_hw_get_rate(parent);
+		if (!parent_rate)
+			return;
+
+		for (; shift < PERIPHERAL_MAX_SHIFT; shift++) {
+			if (parent_rate >> shift <= periph->range.max)
+				break;
+		}
+	}
+
+	periph->auto_div = false;
+	periph->div = shift;
+}
+
+static int clk_sam9x5_peripheral_enable(struct clk_hw *hw)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
+	unsigned long flags;
+
+	if (periph->id < PERIPHERAL_ID_MIN)
+		return 0;
+
+	spin_lock_irqsave(periph->lock, flags);
+	regmap_write(periph->regmap, periph->layout->offset,
+		     (periph->id & periph->layout->pid_mask));
+	regmap_update_bits(periph->regmap, periph->layout->offset,
+			   periph->layout->div_mask | periph->layout->cmd |
+			   AT91_PMC_PCR_EN,
+			   field_prep(periph->layout->div_mask, periph->div) |
+			   periph->layout->cmd |
+			   AT91_PMC_PCR_EN);
+	spin_unlock_irqrestore(periph->lock, flags);
+
+	return 0;
+}
+
+static void clk_sam9x5_peripheral_disable(struct clk_hw *hw)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
+	unsigned long flags;
+
+	if (periph->id < PERIPHERAL_ID_MIN)
+		return;
+
+	spin_lock_irqsave(periph->lock, flags);
+	regmap_write(periph->regmap, periph->layout->offset,
+		     (periph->id & periph->layout->pid_mask));
+	regmap_update_bits(periph->regmap, periph->layout->offset,
+			   AT91_PMC_PCR_EN | periph->layout->cmd,
+			   periph->layout->cmd);
+	spin_unlock_irqrestore(periph->lock, flags);
+}
+
+static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
+	unsigned long flags;
+	unsigned int status;
+
+	if (periph->id < PERIPHERAL_ID_MIN)
+		return 1;
+
+	spin_lock_irqsave(periph->lock, flags);
+	regmap_write(periph->regmap, periph->layout->offset,
+		     (periph->id & periph->layout->pid_mask));
+	regmap_read(periph->regmap, periph->layout->offset, &status);
+	spin_unlock_irqrestore(periph->lock, flags);
+
+	return !!(status & AT91_PMC_PCR_EN);
+}
+
+static unsigned long
+clk_sam9x5_peripheral_recalc_rate(struct clk_hw *hw,
+				  unsigned long parent_rate)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
+	unsigned long flags;
+	unsigned int status;
+
+	if (periph->id < PERIPHERAL_ID_MIN)
+		return parent_rate;
+
+	spin_lock_irqsave(periph->lock, flags);
+	regmap_write(periph->regmap, periph->layout->offset,
+		     (periph->id & periph->layout->pid_mask));
+	regmap_read(periph->regmap, periph->layout->offset, &status);
+	spin_unlock_irqrestore(periph->lock, flags);
+
+	if (status & AT91_PMC_PCR_EN) {
+		periph->div = field_get(periph->layout->div_mask, status);
+		periph->auto_div = false;
+	} else {
+		clk_sam9x5_peripheral_autodiv(periph);
+	}
+
+	return parent_rate >> periph->div;
+}
+
+static void clk_sam9x5_peripheral_best_diff(struct clk_rate_request *req,
+					    struct clk_hw *parent,
+					    unsigned long parent_rate,
+					    u32 shift, long *best_diff,
+					    long *best_rate)
+{
+	unsigned long tmp_rate = parent_rate >> shift;
+	unsigned long 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;
+	}
+}
+
+static int clk_sam9x5_peripheral_determine_rate(struct clk_hw *hw,
+						struct clk_rate_request *req)
+{
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
+	struct clk_hw *parent = clk_hw_get_parent(hw);
+	struct clk_rate_request req_parent = *req;
+	unsigned long parent_rate = clk_hw_get_rate(parent);
+	unsigned long tmp_rate;
+	long best_rate = LONG_MIN;
+	long best_diff = LONG_MIN;
+	u32 shift;
+
+	if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max)
+		return parent_rate;
+
+	/* Fist step: check the available dividers. */
+	for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
+		tmp_rate = parent_rate >> shift;
+
+		if (periph->range.max && tmp_rate > periph->range.max)
+			continue;
+
+		clk_sam9x5_peripheral_best_diff(req, parent, parent_rate,
+						shift, &best_diff, &best_rate);
+
+		if (!best_diff || best_rate <= req->rate)
+			break;
+	}
+
+	if (periph->chg_pid < 0)
+		goto end;
+
+	/* Step two: try to request rate from parent. */
+	parent = clk_hw_get_parent_by_index(hw, periph->chg_pid);
+	if (!parent)
+		goto end;
+
+	for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
+		req_parent.rate = req->rate << shift;
+
+		if (__clk_determine_rate(parent, &req_parent))
+			continue;
+
+		clk_sam9x5_peripheral_best_diff(req, parent, req_parent.rate,
+						shift, &best_diff, &best_rate);
+
+		if (!best_diff)
+			break;
+	}
+end:
+	if (best_rate < 0 ||
+	    (periph->range.max && best_rate > periph->range.max))
+		return -EINVAL;
+
+	pr_debug("PCK: %s, best_rate = %ld, parent clk: %s @ %ld\n",
+		 __func__, best_rate,
+		 __clk_get_name((req->best_parent_hw)->clk),
+		 req->best_parent_rate);
+
+	req->rate = best_rate;
+
+	return 0;
+}
+
+static long clk_sam9x5_peripheral_round_rate(struct clk_hw *hw,
+					     unsigned long rate,
+					     unsigned long *parent_rate)
+{
+	int shift = 0;
+	unsigned long best_rate;
+	unsigned long best_diff;
+	unsigned long cur_rate = *parent_rate;
+	unsigned long cur_diff;
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
+
+	if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max)
+		return *parent_rate;
+
+	if (periph->range.max) {
+		for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
+			cur_rate = *parent_rate >> shift;
+			if (cur_rate <= periph->range.max)
+				break;
+		}
+	}
+
+	if (rate >= cur_rate)
+		return cur_rate;
+
+	best_diff = cur_rate - rate;
+	best_rate = cur_rate;
+	for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
+		cur_rate = *parent_rate >> shift;
+		if (cur_rate < rate)
+			cur_diff = rate - cur_rate;
+		else
+			cur_diff = cur_rate - rate;
+
+		if (cur_diff < best_diff) {
+			best_diff = cur_diff;
+			best_rate = cur_rate;
+		}
+
+		if (!best_diff || cur_rate < rate)
+			break;
+	}
+
+	return best_rate;
+}
+
+static int clk_sam9x5_peripheral_set_rate(struct clk_hw *hw,
+					  unsigned long rate,
+					  unsigned long parent_rate)
+{
+	int shift;
+	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
+	if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max) {
+		if (parent_rate == rate)
+			return 0;
+		else
+			return -EINVAL;
+	}
+
+	if (periph->range.max && rate > periph->range.max)
+		return -EINVAL;
+
+	for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
+		if (parent_rate >> shift == rate) {
+			periph->auto_div = false;
+			periph->div = shift;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static const struct clk_ops sam9x5_peripheral_ops = {
+	.enable = clk_sam9x5_peripheral_enable,
+	.disable = clk_sam9x5_peripheral_disable,
+	.is_enabled = clk_sam9x5_peripheral_is_enabled,
+	.recalc_rate = clk_sam9x5_peripheral_recalc_rate,
+	.round_rate = clk_sam9x5_peripheral_round_rate,
+	.set_rate = clk_sam9x5_peripheral_set_rate,
+};
+
+static const struct clk_ops sam9x5_peripheral_chg_ops = {
+	.enable = clk_sam9x5_peripheral_enable,
+	.disable = clk_sam9x5_peripheral_disable,
+	.is_enabled = clk_sam9x5_peripheral_is_enabled,
+	.recalc_rate = clk_sam9x5_peripheral_recalc_rate,
+	.determine_rate = clk_sam9x5_peripheral_determine_rate,
+	.set_rate = clk_sam9x5_peripheral_set_rate,
+};
+
+struct clk_hw * __init
+at91_clk_register_sam9x5_peripheral(struct regmap *regmap, spinlock_t *lock,
+				    const struct clk_pcr_layout *layout,
+				    const char *name, const char *parent_name,
+				    u32 id, const struct clk_range *range,
+				    int chg_pid)
+{
+	struct clk_sam9x5_peripheral *periph;
+	struct clk_init_data init;
+	struct clk_hw *hw;
+	int ret;
+
+	if (!name || !parent_name)
+		return ERR_PTR(-EINVAL);
+
+	periph = kzalloc(sizeof(*periph), GFP_KERNEL);
+	if (!periph)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+	if (chg_pid < 0) {
+		init.flags = 0;
+		init.ops = &sam9x5_peripheral_ops;
+	} else {
+		init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+			     CLK_SET_RATE_PARENT;
+		init.ops = &sam9x5_peripheral_chg_ops;
+	}
+
+	periph->id = id;
+	periph->hw.init = &init;
+	periph->div = 0;
+	periph->regmap = regmap;
+	periph->lock = lock;
+	if (layout->div_mask)
+		periph->auto_div = true;
+	periph->layout = layout;
+	periph->range = *range;
+	periph->chg_pid = chg_pid;
+
+	hw = &periph->hw;
+	ret = clk_hw_register(NULL, &periph->hw);
+	if (ret) {
+		kfree(periph);
+		hw = ERR_PTR(ret);
+	} else {
+		clk_sam9x5_peripheral_autodiv(periph);
+		pmc_register_id(id);
+	}
+
+	return hw;
+}