[PATCHv8 09/36] clk: ti: add mux-gate clock support
Tero Kristo
t-kristo at ti.com
Wed Oct 9 11:30:40 EDT 2013
This is a multipurpose clock node, which contains support for multiple
sub-clocks. Uses composite clock type to implement the actual functionality.
Signed-off-by: Tero Kristo <t-kristo at ti.com>
Tested-by: Nishanth Menon <nm at ti.com>
Acked-by: Tony Lindgren <tony at atomide.com>
---
.../devicetree/bindings/clock/ti/mux-gate.txt | 100 +++++++++
drivers/clk/ti/Makefile | 3 +-
drivers/clk/ti/mux-gate.c | 214 ++++++++++++++++++++
include/linux/clk/ti.h | 1 +
4 files changed, 317 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/clock/ti/mux-gate.txt
create mode 100644 drivers/clk/ti/mux-gate.c
diff --git a/Documentation/devicetree/bindings/clock/ti/mux-gate.txt b/Documentation/devicetree/bindings/clock/ti/mux-gate.txt
new file mode 100644
index 0000000..dca04db
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/ti/mux-gate.txt
@@ -0,0 +1,100 @@
+Binding for TI mux-gate clock.
+
+Binding status: Unstable - ABI compatibility may be broken in the future
+
+This binding uses the common clock binding[1]. It assumes a
+register-mapped composite clock with multiple different sub-types;
+
+a multiplexer clock with multiple input clock signals or parents, one
+of which can be selected as output, this behaves exactly as [2]
+
+an adjustable clock rate divider, this behaves exactly as [3]
+
+a gating function which can be used to enable and disable the output
+clock, this behaves exactly as [4]
+
+The binding must provide the register mapping to control the mux-gate.
+"reg-names" property is used to specify which sub-function are used
+for this composite clock, and to specify the corresponding control
+register addresses. Optional parameters are specified according to
+the sub-types used.
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+[2] Documentation/devicetree/bindings/clock/ti/mux.txt
+[3] Documentation/devicetree/bindings/clock/ti/divider.txt
+[4] Documentation/devicetree/bindings/clock/ti/gate.txt
+
+Required properties:
+- compatible : shall be one of:
+ "ti,mux-gate-clock" : mux-gate clock which waits until clock is active
+ before returning from clk_enable()
+ "ti,no-wait-mux-gate-clock" : mux-gate clock which does not wait for
+ clock activity
+ "ti,interface-mux-gate-clock" : mux-gate interface clock which waits until
+ clock is active before returning from
+ clk_enable()
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : link phandles of parent clocks
+- reg : base address array for registers controlling the mux-gate
+ sub-functions. Ordered according to "reg-names" property.
+- reg-names : register names property, can have following values:
+ "gate-reg" : base address for gate function control register
+ "mux-reg" : base address for mux function control register
+ "div-reg" : base address for divider function control register
+ Any of these values can be left out, and the corresponding function
+ will not be present in the composite clock either.
+
+Optional properties:
+- ti,gate-bit-shift : number of bits to shift the enable bit for gating
+ function, defaults to 0 if not present
+- ti,mux-bit-shift : number of bits to shift the bit-field for mux
+ function, defaults to 0 if not present
+- ti,div-index-starts-at-one : min-div is mapped to bit-value 1, default 0
+- ti,max-div : maximum divider value for the divider function
+- ti,min-div : minimum divider value for the divider function, defaults to
+ 1 if not present
+- ti,dividers : array of valid divider values for the clock
+
+Examples:
+
+dpll_core_m3x2_ck: dpll_core_m3x2_ck at 4a004134 {
+ #clock-cells = <0>;
+ compatible = "ti,no-wait-mux-gate-clock";
+ clocks = <&dpll_core_x2_ck>;
+ ti,max-div = <31>;
+ reg-names = "gate-reg", "div-reg";
+ reg = <0x4a004134 0x4>, <0x4a004134 0x4>;
+ ti,gate-bit-shift = <8>;
+ ti,div-index-starts-at-one;
+};
+
+auxclk2_src_ck: auxclk2_src_ck at 4a30a318 {
+ #clock-cells = <0>;
+ compatible = "ti,no-wait-mux-gate-clock";
+ clocks = <&sys_clkin_ck>, <&dpll_core_m3x2_ck>, <&dpll_per_m3x2_ck>;
+ reg-names = "gate-reg", "mux-reg";
+ reg = <0x4a30a318 0x4>, <0x4a30a318 0x4>;
+ ti,gate-bit-shift = <8>;
+ ti,mux-bit-shift = <1>;
+};
+
+gpt10_fck: gpt10_fck at 48004a00 {
+ #clock-cells = <0>;
+ compatible = "ti,mux-gate-clock";
+ clocks = <&omap_32k_fck>, <&sys_ck>;
+ reg-names = "gate-reg", "mux-reg";
+ reg = <0x48004a00 0x4>, <0x48004a40 0x4>;
+ ti,gate-bit-shift = <11>;
+ ti,mux-bit-shift = <6>;
+};
+
+ssi_ssr_fck_3430es1: ssi_ssr_fck_3430es1 at 48004a00 {
+ #clock-cells = <0>;
+ compatible = "ti,no-wait-mux-gate-clock";
+ clocks = <&corex2_fck>;
+ ti,div-bit-shift = <8>;
+ ti,dividers = <0>, <1>, <2>, <3>, <4>, <0>, <6>, <0>, <8>;
+ reg-names = "gate-reg", "div-reg";
+ reg = <0x48004a00 0x4>, <0x48004a40 0x4>;
+ ti,gate-bit-shift = <0>;
+};
diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile
index ce8bd06..68d55c9 100644
--- a/drivers/clk/ti/Makefile
+++ b/drivers/clk/ti/Makefile
@@ -1,4 +1,5 @@
ifneq ($(CONFIG_OF),)
obj-y += clk.o dpll.o autoidle.o divider.o \
- fixed-factor.o gate.o clockdomain.o
+ fixed-factor.o gate.o clockdomain.o \
+ mux-gate.o
endif
diff --git a/drivers/clk/ti/mux-gate.c b/drivers/clk/ti/mux-gate.c
new file mode 100644
index 0000000..e7b5bd8
--- /dev/null
+++ b/drivers/clk/ti/mux-gate.c
@@ -0,0 +1,214 @@
+/*
+ * OMAP mux-gate clock support
+ *
+ * Copyright (C) 2013 Texas Instruments, Inc.
+ *
+ * Tero Kristo <t-kristo at ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk/ti.h>
+
+#define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw)
+
+static unsigned long omap_mux_gate_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return clk_divider_ops.recalc_rate(hw, parent_rate);
+}
+
+static long omap_mux_gate_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ return -EINVAL;
+}
+
+static int omap_mux_gate_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ return -EINVAL;
+}
+
+static const struct clk_ops omap_mux_gate_divider_ops = {
+ .recalc_rate = &omap_mux_gate_recalc_rate,
+ .round_rate = &omap_mux_gate_round_rate,
+ .set_rate = &omap_mux_gate_set_rate,
+};
+
+static const struct clk_ops omap_mux_gate_gate_ops = {
+ .enable = &omap2_dflt_clk_enable,
+ .disable = &omap2_dflt_clk_disable,
+ .is_enabled = &omap2_dflt_clk_is_enabled,
+};
+
+static void __init
+_of_ti_mux_gate_clk_setup(struct device_node *node,
+ const struct clk_hw_omap_ops *hw_ops)
+{
+ struct clk *clk;
+ const char *clk_name = node->name;
+ const char **parent_names = NULL;
+ int num_parents;
+ struct clk_hw_omap *gate = NULL;
+ struct clk_divider *div = NULL;
+ struct clk_mux *mux = NULL;
+ const struct clk_ops *mux_ops, *div_ops, *gate_ops;
+ u32 val;
+ int i;
+ u32 min_div, max_div, divider;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ num_parents = of_clk_get_parent_count(node);
+
+ if (num_parents < 1) {
+ pr_err("%s: omap-mux-clock %s must have parent(s)\n", __func__,
+ node->name);
+ return;
+ }
+
+ parent_names = kzalloc((sizeof(char *) * num_parents), GFP_KERNEL);
+
+ for (i = 0; i < num_parents; i++)
+ parent_names[i] = of_clk_get_parent_name(node, i);
+
+ i = of_property_match_string(node, "reg-names", "gate-reg");
+ if (i >= 0) {
+ gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+ gate->enable_reg = of_iomap(node, i);
+ if (of_property_read_u32(node, "ti,gate-bit-shift", &val)) {
+ pr_err("%s: missing gate-bit-shift property for %s\n",
+ __func__, node->name);
+ goto cleanup;
+ }
+ gate->enable_bit = val;
+ gate->ops = hw_ops;
+
+ gate_ops = &omap_mux_gate_gate_ops;
+ }
+
+ i = of_property_match_string(node, "reg-names", "mux-reg");
+ if (i >= 0) {
+ mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+ mux->reg = of_iomap(node, i);
+ mux_ops = &clk_mux_ops;
+ if (of_property_read_u32(node, "ti,mux-bit-shift", &val)) {
+ pr_debug("%s: missing mux-bit-shift property for %s, defaulting to 0\n",
+ __func__, node->name);
+ val = 0;
+ }
+ mux->shift = val;
+
+ mux->mask = num_parents - 1;
+ mux->mask = (1 << fls(mux->mask)) - 1;
+
+ mux_ops = &clk_mux_ops;
+ }
+
+ i = of_property_match_string(node, "reg-names", "div-reg");
+ if (i >= 0) {
+ div = kzalloc(sizeof(*div), GFP_KERNEL);
+ div->reg = of_iomap(node, i);
+
+ div->table = ti_clk_get_div_table(node);
+
+ if (of_property_read_bool(node, "ti,div-index-starts-at-one"))
+ div->flags |= CLK_DIVIDER_ONE_BASED;
+
+ if (!div->table) {
+ if (of_property_read_u32(node, "ti,min-div",
+ &min_div)) {
+ pr_debug("%s: ti,min-div not declared for %s, defaulting to 1\n",
+ __func__, node->name);
+ min_div = 1;
+ }
+
+ if (of_property_read_u32(node, "ti,max-div",
+ &max_div)) {
+ pr_err("%s: ti,max-div not declared for %s\n",
+ __func__, node->name);
+ goto cleanup;
+ }
+
+ val = 0;
+
+ if (div->flags & CLK_DIVIDER_ONE_BASED)
+ val = 1;
+
+ divider = min_div;
+
+ while (divider < max_div) {
+ divider++;
+ val++;
+ }
+ } else {
+ divider = 0;
+ while (div->table[divider].val) {
+ val = div->table[divider].val;
+ divider++;
+ }
+ }
+
+ div->width = fls(val);
+
+ if (of_property_read_u32(node, "ti,div-bit-shift", &val)) {
+ pr_debug("%s: missing div-bit-shift property for %s, defaulting to 0\n",
+ __func__, node->name);
+ val = 0;
+ }
+ div->shift = val;
+
+ div->table = ti_clk_get_div_table(node);
+
+ div_ops = &omap_mux_gate_divider_ops;
+ }
+
+ clk = clk_register_composite(NULL, clk_name,
+ parent_names, num_parents,
+ mux ? &mux->hw : NULL, mux_ops,
+ div ? &div->hw : NULL, div_ops,
+ gate ? &gate->hw : NULL, gate_ops, 0);
+
+ if (!IS_ERR(clk))
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ return;
+cleanup:
+ kfree(mux);
+ kfree(div);
+ kfree(gate);
+ kfree(parent_names);
+}
+
+static void __init of_ti_no_wait_mux_gate_clk_setup(struct device_node *node)
+{
+ _of_ti_mux_gate_clk_setup(node, NULL);
+}
+CLK_OF_DECLARE(ti_no_wait_mux_gate_clk, "ti,no-wait-mux-gate-clock",
+ of_ti_no_wait_mux_gate_clk_setup);
+
+static void __init of_ti_interface_mux_gate_clk_setup(struct device_node *node)
+{
+ _of_ti_mux_gate_clk_setup(node, &clkhwops_iclk_wait);
+}
+CLK_OF_DECLARE(ti_interface_mux_gate_clk, "ti,interface-mux-gate-clock",
+ of_ti_interface_mux_gate_clk_setup);
+
+static void __init of_ti_mux_gate_clk_setup(struct device_node *node)
+{
+ _of_ti_mux_gate_clk_setup(node, &clkhwops_wait);
+}
+CLK_OF_DECLARE(ti_mux_gate_clk, "ti,mux-gate-clock",
+ of_ti_mux_gate_clk_setup);
diff --git a/include/linux/clk/ti.h b/include/linux/clk/ti.h
index e70a2eb..ed4b36e 100644
--- a/include/linux/clk/ti.h
+++ b/include/linux/clk/ti.h
@@ -229,6 +229,7 @@ static inline void of_ti_clk_deny_autoidle_all(void) { }
extern const struct clk_hw_omap_ops clkhwops_omap3_dpll;
extern const struct clk_hw_omap_ops clkhwops_omap4_dpllmx;
extern const struct clk_hw_omap_ops clkhwops_wait;
+extern const struct clk_hw_omap_ops clkhwops_iclk_wait;
extern const struct clk_hw_omap_ops clkhwops_omap3430es2_dss_usbhost_wait;
extern const struct clk_hw_omap_ops clkhwops_am35xx_ipss_module_wait;
--
1.7.9.5
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