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-rw-r--r--drivers/clk/qcom/clk-regmap-mux-div.c231
1 files changed, 231 insertions, 0 deletions
diff --git a/drivers/clk/qcom/clk-regmap-mux-div.c b/drivers/clk/qcom/clk-regmap-mux-div.c
new file mode 100644
index 000000000..6044839da
--- /dev/null
+++ b/drivers/clk/qcom/clk-regmap-mux-div.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2017, Linaro Limited
+ * Author: Georgi Djakov <georgi.djakov@linaro.org>
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/regmap.h>
+
+#include "clk-regmap-mux-div.h"
+
+#define CMD_RCGR 0x0
+#define CMD_RCGR_UPDATE BIT(0)
+#define CMD_RCGR_DIRTY_CFG BIT(4)
+#define CMD_RCGR_ROOT_OFF BIT(31)
+#define CFG_RCGR 0x4
+
+#define to_clk_regmap_mux_div(_hw) \
+ container_of(to_clk_regmap(_hw), struct clk_regmap_mux_div, clkr)
+
+int mux_div_set_src_div(struct clk_regmap_mux_div *md, u32 src, u32 div)
+{
+ int ret, count;
+ u32 val, mask;
+ const char *name = clk_hw_get_name(&md->clkr.hw);
+
+ val = (div << md->hid_shift) | (src << md->src_shift);
+ mask = ((BIT(md->hid_width) - 1) << md->hid_shift) |
+ ((BIT(md->src_width) - 1) << md->src_shift);
+
+ ret = regmap_update_bits(md->clkr.regmap, CFG_RCGR + md->reg_offset,
+ mask, val);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(md->clkr.regmap, CMD_RCGR + md->reg_offset,
+ CMD_RCGR_UPDATE, CMD_RCGR_UPDATE);
+ if (ret)
+ return ret;
+
+ /* Wait for update to take effect */
+ for (count = 500; count > 0; count--) {
+ ret = regmap_read(md->clkr.regmap, CMD_RCGR + md->reg_offset,
+ &val);
+ if (ret)
+ return ret;
+ if (!(val & CMD_RCGR_UPDATE))
+ return 0;
+ udelay(1);
+ }
+
+ pr_err("%s: RCG did not update its configuration", name);
+ return -EBUSY;
+}
+EXPORT_SYMBOL_GPL(mux_div_set_src_div);
+
+static void mux_div_get_src_div(struct clk_regmap_mux_div *md, u32 *src,
+ u32 *div)
+{
+ u32 val, d, s;
+ const char *name = clk_hw_get_name(&md->clkr.hw);
+
+ regmap_read(md->clkr.regmap, CMD_RCGR + md->reg_offset, &val);
+
+ if (val & CMD_RCGR_DIRTY_CFG) {
+ pr_err("%s: RCG configuration is pending\n", name);
+ return;
+ }
+
+ regmap_read(md->clkr.regmap, CFG_RCGR + md->reg_offset, &val);
+ s = (val >> md->src_shift);
+ s &= BIT(md->src_width) - 1;
+ *src = s;
+
+ d = (val >> md->hid_shift);
+ d &= BIT(md->hid_width) - 1;
+ *div = d;
+}
+
+static inline bool is_better_rate(unsigned long req, unsigned long best,
+ unsigned long new)
+{
+ return (req <= new && new < best) || (best < req && best < new);
+}
+
+static int mux_div_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw);
+ unsigned int i, div, max_div;
+ unsigned long actual_rate, best_rate = 0;
+ unsigned long req_rate = req->rate;
+
+ for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
+ struct clk_hw *parent = clk_hw_get_parent_by_index(hw, i);
+ unsigned long parent_rate = clk_hw_get_rate(parent);
+
+ max_div = BIT(md->hid_width) - 1;
+ for (div = 1; div < max_div; div++) {
+ parent_rate = mult_frac(req_rate, div, 2);
+ parent_rate = clk_hw_round_rate(parent, parent_rate);
+ actual_rate = mult_frac(parent_rate, 2, div);
+
+ if (is_better_rate(req_rate, best_rate, actual_rate)) {
+ best_rate = actual_rate;
+ req->rate = best_rate;
+ req->best_parent_rate = parent_rate;
+ req->best_parent_hw = parent;
+ }
+
+ if (actual_rate < req_rate || best_rate <= req_rate)
+ break;
+ }
+ }
+
+ if (!best_rate)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int __mux_div_set_rate_and_parent(struct clk_hw *hw, unsigned long rate,
+ unsigned long prate, u32 src)
+{
+ struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw);
+ int ret;
+ u32 div, max_div, best_src = 0, best_div = 0;
+ unsigned int i;
+ unsigned long actual_rate, best_rate = 0;
+
+ for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
+ struct clk_hw *parent = clk_hw_get_parent_by_index(hw, i);
+ unsigned long parent_rate = clk_hw_get_rate(parent);
+
+ max_div = BIT(md->hid_width) - 1;
+ for (div = 1; div < max_div; div++) {
+ parent_rate = mult_frac(rate, div, 2);
+ parent_rate = clk_hw_round_rate(parent, parent_rate);
+ actual_rate = mult_frac(parent_rate, 2, div);
+
+ if (is_better_rate(rate, best_rate, actual_rate)) {
+ best_rate = actual_rate;
+ best_src = md->parent_map[i];
+ best_div = div - 1;
+ }
+
+ if (actual_rate < rate || best_rate <= rate)
+ break;
+ }
+ }
+
+ ret = mux_div_set_src_div(md, best_src, best_div);
+ if (!ret) {
+ md->div = best_div;
+ md->src = best_src;
+ }
+
+ return ret;
+}
+
+static u8 mux_div_get_parent(struct clk_hw *hw)
+{
+ struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw);
+ const char *name = clk_hw_get_name(hw);
+ u32 i, div, src = 0;
+
+ mux_div_get_src_div(md, &src, &div);
+
+ for (i = 0; i < clk_hw_get_num_parents(hw); i++)
+ if (src == md->parent_map[i])
+ return i;
+
+ pr_err("%s: Can't find parent with src %d\n", name, src);
+ return 0;
+}
+
+static int mux_div_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw);
+
+ return mux_div_set_src_div(md, md->parent_map[index], md->div);
+}
+
+static int mux_div_set_rate(struct clk_hw *hw,
+ unsigned long rate, unsigned long prate)
+{
+ struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw);
+
+ return __mux_div_set_rate_and_parent(hw, rate, prate, md->src);
+}
+
+static int mux_div_set_rate_and_parent(struct clk_hw *hw, unsigned long rate,
+ unsigned long prate, u8 index)
+{
+ struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw);
+
+ return __mux_div_set_rate_and_parent(hw, rate, prate,
+ md->parent_map[index]);
+}
+
+static unsigned long mux_div_recalc_rate(struct clk_hw *hw, unsigned long prate)
+{
+ struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw);
+ u32 div, src;
+ int i, num_parents = clk_hw_get_num_parents(hw);
+ const char *name = clk_hw_get_name(hw);
+
+ mux_div_get_src_div(md, &src, &div);
+ for (i = 0; i < num_parents; i++)
+ if (src == md->parent_map[i]) {
+ struct clk_hw *p = clk_hw_get_parent_by_index(hw, i);
+ unsigned long parent_rate = clk_hw_get_rate(p);
+
+ return mult_frac(parent_rate, 2, div + 1);
+ }
+
+ pr_err("%s: Can't find parent %d\n", name, src);
+ return 0;
+}
+
+const struct clk_ops clk_regmap_mux_div_ops = {
+ .get_parent = mux_div_get_parent,
+ .set_parent = mux_div_set_parent,
+ .set_rate = mux_div_set_rate,
+ .set_rate_and_parent = mux_div_set_rate_and_parent,
+ .determine_rate = mux_div_determine_rate,
+ .recalc_rate = mux_div_recalc_rate,
+};
+EXPORT_SYMBOL_GPL(clk_regmap_mux_div_ops);