summaryrefslogtreecommitdiffstats
path: root/drivers/clk/zynqmp/clk-mux-zynqmp.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/clk/zynqmp/clk-mux-zynqmp.c')
-rw-r--r--drivers/clk/zynqmp/clk-mux-zynqmp.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/drivers/clk/zynqmp/clk-mux-zynqmp.c b/drivers/clk/zynqmp/clk-mux-zynqmp.c
new file mode 100644
index 000000000..9b5d3050b
--- /dev/null
+++ b/drivers/clk/zynqmp/clk-mux-zynqmp.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Zynq UltraScale+ MPSoC mux
+ *
+ * Copyright (C) 2016-2018 Xilinx
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include "clk-zynqmp.h"
+
+/*
+ * DOC: basic adjustable multiplexer clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare only ensures that parents are prepared
+ * enable - clk_enable only ensures that parents are enabled
+ * rate - rate is only affected by parent switching. No clk_set_rate support
+ * parent - parent is adjustable through clk_set_parent
+ */
+
+/**
+ * struct zynqmp_clk_mux - multiplexer clock
+ *
+ * @hw: handle between common and hardware-specific interfaces
+ * @flags: hardware-specific flags
+ * @clk_id: Id of clock
+ */
+struct zynqmp_clk_mux {
+ struct clk_hw hw;
+ u8 flags;
+ u32 clk_id;
+};
+
+#define to_zynqmp_clk_mux(_hw) container_of(_hw, struct zynqmp_clk_mux, hw)
+
+/**
+ * zynqmp_clk_mux_get_parent() - Get parent of clock
+ * @hw: handle between common and hardware-specific interfaces
+ *
+ * Return: Parent index on success or number of parents in case of error
+ */
+static u8 zynqmp_clk_mux_get_parent(struct clk_hw *hw)
+{
+ struct zynqmp_clk_mux *mux = to_zynqmp_clk_mux(hw);
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 clk_id = mux->clk_id;
+ u32 val;
+ int ret;
+
+ ret = zynqmp_pm_clock_getparent(clk_id, &val);
+
+ if (ret) {
+ pr_debug("%s() getparent failed for clock: %s, ret = %d\n",
+ __func__, clk_name, ret);
+ /*
+ * clk_core_get_parent_by_index() takes num_parents as incorrect
+ * index which is exactly what I want to return here
+ */
+ return clk_hw_get_num_parents(hw);
+ }
+
+ return val;
+}
+
+/**
+ * zynqmp_clk_mux_set_parent() - Set parent of clock
+ * @hw: handle between common and hardware-specific interfaces
+ * @index: Parent index
+ *
+ * Return: 0 on success else error+reason
+ */
+static int zynqmp_clk_mux_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct zynqmp_clk_mux *mux = to_zynqmp_clk_mux(hw);
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 clk_id = mux->clk_id;
+ int ret;
+
+ ret = zynqmp_pm_clock_setparent(clk_id, index);
+
+ if (ret)
+ pr_debug("%s() set parent failed for clock: %s, ret = %d\n",
+ __func__, clk_name, ret);
+
+ return ret;
+}
+
+static const struct clk_ops zynqmp_clk_mux_ops = {
+ .get_parent = zynqmp_clk_mux_get_parent,
+ .set_parent = zynqmp_clk_mux_set_parent,
+ .determine_rate = __clk_mux_determine_rate_closest,
+};
+
+static const struct clk_ops zynqmp_clk_mux_ro_ops = {
+ .get_parent = zynqmp_clk_mux_get_parent,
+};
+
+static inline unsigned long zynqmp_clk_map_mux_ccf_flags(
+ const u32 zynqmp_type_flag)
+{
+ unsigned long ccf_flag = 0;
+
+ if (zynqmp_type_flag & ZYNQMP_CLK_MUX_INDEX_ONE)
+ ccf_flag |= CLK_MUX_INDEX_ONE;
+ if (zynqmp_type_flag & ZYNQMP_CLK_MUX_INDEX_BIT)
+ ccf_flag |= CLK_MUX_INDEX_BIT;
+ if (zynqmp_type_flag & ZYNQMP_CLK_MUX_HIWORD_MASK)
+ ccf_flag |= CLK_MUX_HIWORD_MASK;
+ if (zynqmp_type_flag & ZYNQMP_CLK_MUX_READ_ONLY)
+ ccf_flag |= CLK_MUX_READ_ONLY;
+ if (zynqmp_type_flag & ZYNQMP_CLK_MUX_ROUND_CLOSEST)
+ ccf_flag |= CLK_MUX_ROUND_CLOSEST;
+ if (zynqmp_type_flag & ZYNQMP_CLK_MUX_BIG_ENDIAN)
+ ccf_flag |= CLK_MUX_BIG_ENDIAN;
+
+ return ccf_flag;
+}
+
+/**
+ * zynqmp_clk_register_mux() - Register a mux table with the clock
+ * framework
+ * @name: Name of this clock
+ * @clk_id: Id of this clock
+ * @parents: Name of this clock's parents
+ * @num_parents: Number of parents
+ * @nodes: Clock topology node
+ *
+ * Return: clock hardware of the registered clock mux
+ */
+struct clk_hw *zynqmp_clk_register_mux(const char *name, u32 clk_id,
+ const char * const *parents,
+ u8 num_parents,
+ const struct clock_topology *nodes)
+{
+ struct zynqmp_clk_mux *mux;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ int ret;
+
+ mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+ if (!mux)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ if (nodes->type_flag & CLK_MUX_READ_ONLY)
+ init.ops = &zynqmp_clk_mux_ro_ops;
+ else
+ init.ops = &zynqmp_clk_mux_ops;
+
+ init.flags = zynqmp_clk_map_common_ccf_flags(nodes->flag);
+
+ init.parent_names = parents;
+ init.num_parents = num_parents;
+ mux->flags = zynqmp_clk_map_mux_ccf_flags(nodes->type_flag);
+ mux->hw.init = &init;
+ mux->clk_id = clk_id;
+
+ hw = &mux->hw;
+ ret = clk_hw_register(NULL, hw);
+ if (ret) {
+ kfree(mux);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}