1 files changed, 278 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-programmable.c b/drivers/clk/at91/clk-programmable.c
new file mode 100644
index 000000000..6c4b259d3
--- /dev/null
+++ b/drivers/clk/at91/clk-programmable.c
@@ -0,0 +1,278 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ */
+
+#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 PROG_ID_MAX		7
+
+#define PROG_STATUS_MASK(id)	(1 << ((id) + 8))
+#define PROG_PRES(layout, pckr)	((pckr >> layout->pres_shift) & layout->pres_mask)
+#define PROG_MAX_RM9200_CSS	3
+
+struct clk_programmable {
+	struct clk_hw hw;
+	struct regmap *regmap;
+	u32 *mux_table;
+	u8 id;
+	const struct clk_programmable_layout *layout;
+	struct at91_clk_pms pms;
+};
+
+#define to_clk_programmable(hw) container_of(hw, struct clk_programmable, hw)
+
+static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw,
+						  unsigned long parent_rate)
+{
+	struct clk_programmable *prog = to_clk_programmable(hw);
+	const struct clk_programmable_layout *layout = prog->layout;
+	unsigned int pckr;
+	unsigned long rate;
+
+	regmap_read(prog->regmap, AT91_PMC_PCKR(prog->id), &pckr);
+
+	if (layout->is_pres_direct)
+		rate = parent_rate / (PROG_PRES(layout, pckr) + 1);
+	else
+		rate = parent_rate >> PROG_PRES(layout, pckr);
+
+	return rate;
+}
+
+static int clk_programmable_determine_rate(struct clk_hw *hw,
+					   struct clk_rate_request *req)
+{
+	struct clk_programmable *prog = to_clk_programmable(hw);
+	const struct clk_programmable_layout *layout = prog->layout;
+	struct clk_hw *parent;
+	long best_rate = -EINVAL;
+	unsigned long parent_rate;
+	unsigned long tmp_rate = 0;
+	int shift;
+	int i;
+
+	for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
+		parent = clk_hw_get_parent_by_index(hw, i);
+		if (!parent)
+			continue;
+
+		parent_rate = clk_hw_get_rate(parent);
+		if (layout->is_pres_direct) {
+			for (shift = 0; shift <= layout->pres_mask; shift++) {
+				tmp_rate = parent_rate / (shift + 1);
+				if (tmp_rate <= req->rate)
+					break;
+			}
+		} else {
+			for (shift = 0; shift < layout->pres_mask; shift++) {
+				tmp_rate = parent_rate >> shift;
+				if (tmp_rate <= req->rate)
+					break;
+			}
+		}
+
+		if (tmp_rate > req->rate)
+			continue;
+
+		if (best_rate < 0 ||
+		    (req->rate - tmp_rate) < (req->rate - best_rate)) {
+			best_rate = tmp_rate;
+			req->best_parent_rate = parent_rate;
+			req->best_parent_hw = parent;
+		}
+
+		if (!best_rate)
+			break;
+	}
+
+	if (best_rate < 0)
+		return best_rate;
+
+	req->rate = best_rate;
+	return 0;
+}
+
+static int clk_programmable_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct clk_programmable *prog = to_clk_programmable(hw);
+	const struct clk_programmable_layout *layout = prog->layout;
+	unsigned int mask = layout->css_mask;
+	unsigned int pckr = index;
+
+	if (layout->have_slck_mck)
+		mask |= AT91_PMC_CSSMCK_MCK;
+
+	if (prog->mux_table)
+		pckr = clk_mux_index_to_val(prog->mux_table, 0, index);
+
+	if (index > layout->css_mask) {
+		if (index > PROG_MAX_RM9200_CSS && !layout->have_slck_mck)
+			return -EINVAL;
+
+		pckr |= AT91_PMC_CSSMCK_MCK;
+	}
+
+	regmap_update_bits(prog->regmap, AT91_PMC_PCKR(prog->id), mask, pckr);
+
+	return 0;
+}
+
+static u8 clk_programmable_get_parent(struct clk_hw *hw)
+{
+	struct clk_programmable *prog = to_clk_programmable(hw);
+	const struct clk_programmable_layout *layout = prog->layout;
+	unsigned int pckr;
+	u8 ret;
+
+	regmap_read(prog->regmap, AT91_PMC_PCKR(prog->id), &pckr);
+
+	ret = pckr & layout->css_mask;
+
+	if (layout->have_slck_mck && (pckr & AT91_PMC_CSSMCK_MCK) && !ret)
+		ret = PROG_MAX_RM9200_CSS + 1;
+
+	if (prog->mux_table)
+		ret = clk_mux_val_to_index(&prog->hw, prog->mux_table, 0, ret);
+
+	return ret;
+}
+
+static int clk_programmable_set_rate(struct clk_hw *hw, unsigned long rate,
+				     unsigned long parent_rate)
+{
+	struct clk_programmable *prog = to_clk_programmable(hw);
+	const struct clk_programmable_layout *layout = prog->layout;
+	unsigned long div = parent_rate / rate;
+	int shift = 0;
+
+	if (!div)
+		return -EINVAL;
+
+	if (layout->is_pres_direct) {
+		shift = div - 1;
+
+		if (shift > layout->pres_mask)
+			return -EINVAL;
+	} else {
+		shift = fls(div) - 1;
+
+		if (div != (1 << shift))
+			return -EINVAL;
+
+		if (shift >= layout->pres_mask)
+			return -EINVAL;
+	}
+
+	regmap_update_bits(prog->regmap, AT91_PMC_PCKR(prog->id),
+			   layout->pres_mask << layout->pres_shift,
+			   shift << layout->pres_shift);
+
+	return 0;
+}
+
+static int clk_programmable_save_context(struct clk_hw *hw)
+{
+	struct clk_programmable *prog = to_clk_programmable(hw);
+	struct clk_hw *parent_hw = clk_hw_get_parent(hw);
+
+	prog->pms.parent = clk_programmable_get_parent(hw);
+	prog->pms.parent_rate = clk_hw_get_rate(parent_hw);
+	prog->pms.rate = clk_programmable_recalc_rate(hw, prog->pms.parent_rate);
+
+	return 0;
+}
+
+static void clk_programmable_restore_context(struct clk_hw *hw)
+{
+	struct clk_programmable *prog = to_clk_programmable(hw);
+	int ret;
+
+	ret = clk_programmable_set_parent(hw, prog->pms.parent);
+	if (ret)
+		return;
+
+	clk_programmable_set_rate(hw, prog->pms.rate, prog->pms.parent_rate);
+}
+
+static const struct clk_ops programmable_ops = {
+	.recalc_rate = clk_programmable_recalc_rate,
+	.determine_rate = clk_programmable_determine_rate,
+	.get_parent = clk_programmable_get_parent,
+	.set_parent = clk_programmable_set_parent,
+	.set_rate = clk_programmable_set_rate,
+	.save_context = clk_programmable_save_context,
+	.restore_context = clk_programmable_restore_context,
+};
+
+struct clk_hw * __init
+at91_clk_register_programmable(struct regmap *regmap,
+			       const char *name, const char **parent_names,
+			       u8 num_parents, u8 id,
+			       const struct clk_programmable_layout *layout,
+			       u32 *mux_table)
+{
+	struct clk_programmable *prog;
+	struct clk_hw *hw;
+	struct clk_init_data init;
+	int ret;
+
+	if (id > PROG_ID_MAX)
+		return ERR_PTR(-EINVAL);
+
+	prog = kzalloc(sizeof(*prog), GFP_KERNEL);
+	if (!prog)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &programmable_ops;
+	init.parent_names = parent_names;
+	init.num_parents = num_parents;
+	init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+	prog->id = id;
+	prog->layout = layout;
+	prog->hw.init = &init;
+	prog->regmap = regmap;
+	prog->mux_table = mux_table;
+
+	hw = &prog->hw;
+	ret = clk_hw_register(NULL, &prog->hw);
+	if (ret) {
+		kfree(prog);
+		hw = ERR_PTR(ret);
+	}
+
+	return hw;
+}
+
+const struct clk_programmable_layout at91rm9200_programmable_layout = {
+	.pres_mask = 0x7,
+	.pres_shift = 2,
+	.css_mask = 0x3,
+	.have_slck_mck = 0,
+	.is_pres_direct = 0,
+};
+
+const struct clk_programmable_layout at91sam9g45_programmable_layout = {
+	.pres_mask = 0x7,
+	.pres_shift = 2,
+	.css_mask = 0x3,
+	.have_slck_mck = 1,
+	.is_pres_direct = 0,
+};
+
+const struct clk_programmable_layout at91sam9x5_programmable_layout = {
+	.pres_mask = 0x7,
+	.pres_shift = 4,
+	.css_mask = 0x7,
+	.have_slck_mck = 0,
+	.is_pres_direct = 0,
+};