This patch adds support for TI specific gate clocks. These behave as basic
gate-clock, but have different ops / hw-ops for controlling the actual
gate, for example waiting until the clock is ready. Several sub-types
are supported:
- ti,gate-clock: basic gate clock with default ops/hwops
- ti,clkdm-gate-clock: clockdomain level gate control
- ti,dss-gate-clock: gate clock with DSS specific hardware handling
- ti,am35xx-gate-clock: gate clock with AM35xx specific hardware handling
- ti,hsdiv-gate-clock: gate clock with OMAP36xx hardware errata handling
Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
Tested-by: Nishanth Menon <nm@xxxxxx>
Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
---
.../devicetree/bindings/clock/ti/gate.txt | 77 ++++++++
arch/arm/mach-omap2/clock.h | 28 ---
drivers/clk/ti/Makefile | 2 +-
drivers/clk/ti/gate.c | 184 ++++++++++++++++++++
include/linux/clk/ti.h | 35 ++++
5 files changed, 297 insertions(+), 29 deletions(-)
create mode 100644 Documentation/devicetree/bindings/clock/ti/gate.txt
create mode 100644 drivers/clk/ti/gate.c
diff --git a/Documentation/devicetree/bindings/clock/ti/gate.txt b/Documentation/devicetree/bindings/clock/ti/gate.txt
new file mode 100644
index 0000000..276adc4
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/ti/gate.txt
@@ -0,0 +1,77 @@
+Binding for Texas Instruments gate clock.
+
+Binding status: Unstable - ABI compatibility may be broken in the future
+
+This binding uses the common clock binding[1]. This clock is
+quite much similar to the basic gate-clock [2], however,
+it supports a number of additional features. If no register
+is provided for this clock, the code assumes that a clockdomain
+will be controlled instead and the corresponding hw-ops for
+that is used.
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+[2] Documentation/devicetree/bindings/clock/gate-clock.txt
+[3] Documentation/devicetree/bindings/clock/ti/clockdomain.txt
+
+Required properties:
+- compatible : shall be one of:
+ "ti,gate-clock" - basic gate clock
+ "ti,wait-gate-clock" - gate clock which waits until clock is active before
+ returning from clk_enable()
+ "ti,dss-gate-clock" - gate clock with DSS specific hardware handling
+ "ti,am35xx-gate-clock" - gate clock with AM35xx specific hardware handling
+ "ti,clkdm-gate-clock" - clockdomain gate clock, which derives its functional
+ clock directly from a clockdomain, see [3] how
+ to map clockdomains properly
+ "ti,hsdiv-gate-clock" - gate clock with OMAP36xx specific hardware handling,
+ required for a hardware errata
+- #clock-cells : from common clock binding; shall be set to 0
+- clocks : link to phandle of parent clock
+- reg : base address for register controlling adjustable gate, not needed for
+ ti,clkdm-gate-clock type
+- ti,bit-shift : bit shift for programming the clock gate, not needed for
+ ti,clkdm-gate-clock type
+
+Optional properties:
+- ti,set-bit-to-disable : inverts default gate programming. Setting the bit
+ gates the clock and clearing the bit ungates the clock.
+
+Examples:
+ mmchs2_fck: mmchs2_fck@48004a00 {
+ #clock-cells = <0>;
+ compatible = "ti,gate-clock";
+ clocks = <&core_96m_fck>;
+ reg = <0x48004a00 0x4>;
+ ti,bit-shift = <25>;
+ };
+
+ dss1_alwon_fck_3430es2: dss1_alwon_fck_3430es2@48004e00 {
+ #clock-cells = <0>;
+ compatible = "ti,dss-gate-clock";
+ clocks = <&dpll4_m4x2_ck>;
+ reg = <0x48004e00 0x4>;
+ ti,bit-shift = <0>;
+ };
+
+ emac_ick: emac_ick@4800259c {
+ #clock-cells = <0>;
+ compatible = "ti,am35xx-gate-clock";
+ clocks = <&ipss_ick>;
+ reg = <0x4800259c 0x4>;
+ ti,bit-shift = <1>;
+ };
+
+ emu_src_ck: emu_src_ck {
+ #clock-cells = <0>;
+ compatible = "ti,clkdm-gate-clock";
+ clocks = <&emu_src_mux_ck>;
+ };
+
+ dpll4_m2x2_ck: dpll4_m2x2_ck@48004d00 {
+ #clock-cells = <0>;
+ compatible = "ti,hsdiv-gate-clock";
+ clocks = <&dpll4_m2x2_mul_ck>;
+ ti,bit-shift = <0x1b>;
+ reg = <0x48004d00 0x4>;
+ ti,set-bit-to-disable;
+ };
diff --git a/arch/arm/mach-omap2/clock.h b/arch/arm/mach-omap2/clock.h
index 079536a..f0b7218 100644
--- a/arch/arm/mach-omap2/clock.h
+++ b/arch/arm/mach-omap2/clock.h
@@ -179,25 +179,6 @@ struct clksel {
const struct clksel_rate *rates;
};
-/*
- * struct clk.flags possibilities
- *
- * XXX document the rest of the clock flags here
- *
- * CLOCK_CLKOUTX2: (OMAP4 only) DPLL CLKOUT and CLKOUTX2 GATE_CTRL
- * bits share the same register. This flag allows the
- * omap4_dpllmx*() code to determine which GATE_CTRL bit field
- * should be used. This is a temporary solution - a better approach
- * would be to associate clock type-specific data with the clock,
- * similar to the struct dpll_data approach.
- */
-#define ENABLE_REG_32BIT (1 << 0) /* Use 32-bit access */
-#define CLOCK_IDLE_CONTROL (1 << 1)
-#define CLOCK_NO_IDLE_PARENT (1 << 2)
-#define ENABLE_ON_INIT (1 << 3) /* Enable upon framework init */
-#define INVERT_ENABLE (1 << 4) /* 0 enables, 1 disables */
-#define CLOCK_CLKOUTX2 (1 << 5)
-
struct clk_hw_omap_ops {
void (*find_idlest)(struct clk_hw_omap *oclk,
void __iomem **idlest_reg,
@@ -260,9 +241,6 @@ extern void omap2_clkt_iclk_deny_idle(struct clk_hw_omap *clk);
unsigned long omap2_get_dpll_rate(struct clk_hw_omap *clk);
-int omap2_dflt_clk_enable(struct clk_hw *hw);
-void omap2_dflt_clk_disable(struct clk_hw *hw);
-int omap2_dflt_clk_is_enabled(struct clk_hw *hw);
void omap2_clk_dflt_find_companion(struct clk_hw_omap *clk,
void __iomem **other_reg,
u8 *other_bit);
@@ -292,15 +270,12 @@ extern const struct clksel_rate dsp_ick_rates[];
extern struct clk dummy_ck;
extern const struct clk_hw_omap_ops clkhwops_iclk_wait;
-extern const struct clk_hw_omap_ops clkhwops_wait;
extern const struct clk_hw_omap_ops clkhwops_iclk;
extern const struct clk_hw_omap_ops clkhwops_omap3430es2_ssi_wait;
extern const struct clk_hw_omap_ops clkhwops_omap3430es2_iclk_ssi_wait;
-extern const struct clk_hw_omap_ops clkhwops_omap3430es2_dss_usbhost_wait;
extern const struct clk_hw_omap_ops clkhwops_omap3430es2_iclk_dss_usbhost_wait;
extern const struct clk_hw_omap_ops clkhwops_omap3430es2_iclk_hsotgusb_wait;
extern const struct clk_hw_omap_ops clkhwops_omap3430es2_hsotgusb_wait;
-extern const struct clk_hw_omap_ops clkhwops_am35xx_ipss_module_wait;
extern const struct clk_hw_omap_ops clkhwops_am35xx_ipss_wait;
extern const struct clk_hw_omap_ops clkhwops_apll54;
extern const struct clk_hw_omap_ops clkhwops_apll96;
@@ -318,8 +293,5 @@ extern const struct clksel_rate div31_1to31_rates[];
extern int am33xx_clk_init(void);
-extern int omap2_clkops_enable_clkdm(struct clk_hw *hw);
-extern void omap2_clkops_disable_clkdm(struct clk_hw *hw);
-
extern void omap_clocks_register(struct omap_clk *oclks, int cnt);
#endif
diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile
index a9b986a..63b1c45 100644
--- a/drivers/clk/ti/Makefile
+++ b/drivers/clk/ti/Makefile
@@ -1,4 +1,4 @@
ifneq ($(CONFIG_OF),)
obj-y += clk.o dpll.o autoidle.o divider.o \
- fixed-factor.o
+ fixed-factor.o gate.o
endif
diff --git a/drivers/clk/ti/gate.c b/drivers/clk/ti/gate.c
new file mode 100644
index 0000000..cc2a272
--- /dev/null
+++ b/drivers/clk/ti/gate.c
@@ -0,0 +1,184 @@
+/*
+ * OMAP gate clock support
+ *
+ * Copyright (C) 2013 Texas Instruments, Inc.
+ *
+ * Tero Kristo <t-kristo@xxxxxx>
+ *
+ * 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 int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk);
+
+static const struct clk_ops omap_gate_clkdm_clk_ops = {
+ .init = &omap2_init_clk_clkdm,
+ .enable = &omap2_clkops_enable_clkdm,
+ .disable = &omap2_clkops_disable_clkdm,
+};
+
+static const struct clk_ops omap_gate_clk_ops = {
+ .init = &omap2_init_clk_clkdm,
+ .enable = &omap2_dflt_clk_enable,
+ .disable = &omap2_dflt_clk_disable,
+ .is_enabled = &omap2_dflt_clk_is_enabled,
+};
+
+static const struct clk_ops omap_gate_clk_hsdiv_restore_ops = {
+ .init = &omap2_init_clk_clkdm,
+ .enable = &omap36xx_gate_clk_enable_with_hsdiv_restore,
+ .disable = &omap2_dflt_clk_disable,
+ .is_enabled = &omap2_dflt_clk_is_enabled,
+};
+
+/**
+ * omap36xx_gate_clk_enable_with_hsdiv_restore - enable clocks suffering
+ * from HSDivider PWRDN problem Implements Errata ID: i556.
+ * @clk: DPLL output struct clk
+ *
+ * 3630 only: dpll3_m3_ck, dpll4_m2_ck, dpll4_m3_ck, dpll4_m4_ck,
+ * dpll4_m5_ck & dpll4_m6_ck dividers gets loaded with reset
+ * valueafter their respective PWRDN bits are set. Any dummy write
+ * (Any other value different from the Read value) to the
+ * corresponding CM_CLKSEL register will refresh the dividers.
+ */
+static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk)
+{
+ struct clk_divider *parent;
+ struct clk_hw *parent_hw;
+ u32 dummy_v, orig_v;
+ int ret;
+
+ /* Clear PWRDN bit of HSDIVIDER */
+ ret = omap2_dflt_clk_enable(clk);
+
+ /* Parent is the x2 node, get parent of parent for the m2 div */
+ parent_hw = __clk_get_hw(__clk_get_parent(__clk_get_parent(clk->clk)));
+ parent = to_clk_divider(parent_hw);
+
+ /* Restore the dividers */
+ if (!ret) {
+ orig_v = __raw_readl(parent->reg);
+ dummy_v = orig_v;
+
+ /* Write any other value different from the Read value */
+ dummy_v ^= (1 << parent->shift);
+ __raw_writel(dummy_v, parent->reg);
+
+ /* Write the original divider */
+ __raw_writel(orig_v, parent->reg);
+ }
+
+ return ret;
+}
+
+static void __init _of_ti_gate_clk_setup(struct device_node *node,
+ void __iomem *reg,
+ const struct clk_ops *ops,
+ const struct clk_hw_omap_ops *hw_ops)
+{
+ struct clk *clk;
+ struct clk_init_data init = { NULL };
+ struct clk_hw_omap *clk_hw;
+ const char *clk_name = node->name;
+ const char *parent_name;
+ u32 val;
+
+ clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
+ if (!clk_hw) {
+ pr_err("%s: could not allocate clk_hw_omap\n", __func__);
+ return;
+ }
+
+ clk_hw->hw.init = &init;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ init.name = clk_name;
+ init.ops = ops;
+ clk_hw->enable_reg = reg;
+ if (!of_property_read_u32(node, "ti,bit-shift", &val))
+ clk_hw->enable_bit = val;
+ clk_hw->ops = hw_ops;
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ if (of_property_read_bool(node, "ti,set-rate-parent"))
+ init.flags |= CLK_SET_RATE_PARENT;
+
+ if (of_property_read_bool(node, "ti,set-bit-to-disable"))
+ clk_hw->flags |= INVERT_ENABLE;
+
+ clk = clk_register(NULL, &clk_hw->hw);
+
+ if (!IS_ERR(clk))
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+}
+
+static void __init of_ti_clkdm_gate_clk_setup(struct device_node *node)
+{
+ _of_ti_gate_clk_setup(node, NULL, &omap_gate_clkdm_clk_ops, NULL);
+}
+CLK_OF_DECLARE(ti_clkdm_gate_clk, "ti,clkdm-gate-clock",
+ of_ti_clkdm_gate_clk_setup);
+
+static void __init of_ti_hsdiv_gate_clk_setup(struct device_node *node)
+{
+ void __iomem *reg = of_iomap(node, 0);
+ _of_ti_gate_clk_setup(node, reg, &omap_gate_clk_hsdiv_restore_ops,
+ &clkhwops_wait);
+}
+CLK_OF_DECLARE(ti_hsdiv_gate_clk, "ti,hsdiv-gate-clock",
+ of_ti_hsdiv_gate_clk_setup);
+
+static void __init of_ti_gate_clk_setup(struct device_node *node)
+{
+ void __iomem *reg = of_iomap(node, 0);
+ _of_ti_gate_clk_setup(node, reg, &omap_gate_clk_ops, NULL);
+}
+CLK_OF_DECLARE(ti_gate_clk, "ti,gate-clock", of_ti_gate_clk_setup)
+
+static void __init of_ti_wait_gate_clk_setup(struct device_node *node)
+{
+ void __iomem *reg = of_iomap(node, 0);
+ _of_ti_gate_clk_setup(node, reg, &omap_gate_clk_ops, &clkhwops_wait);
+}
+CLK_OF_DECLARE(ti_wait_gate_clk, "ti,wait-gate-clock",
+ of_ti_wait_gate_clk_setup);
+
+#ifdef CONFIG_ARCH_OMAP3
+static void __init of_ti_am35xx_gate_clk_setup(struct device_node *node)
+{
+ void __iomem *reg = of_iomap(node, 0);
+ _of_ti_gate_clk_setup(node, reg, &omap_gate_clk_ops,
+ &clkhwops_am35xx_ipss_module_wait);
+}
+CLK_OF_DECLARE(ti_am35xx_gate_clk, "ti,am35xx-gate-clock",
+ of_ti_am35xx_gate_clk_setup);
+
+static void __init of_ti_dss_gate_clk_setup(struct device_node *node)
+{
+ void __iomem *reg = of_iomap(node, 0);
+ _of_ti_gate_clk_setup(node, reg, &omap_gate_clk_ops,
+ &clkhwops_omap3430es2_dss_usbhost_wait);
+}
+CLK_OF_DECLARE(ti_dss_gate_clk, "ti,dss-gate-clock",
+ of_ti_dss_gate_clk_setup);
+#endif
diff --git a/include/linux/clk/ti.h b/include/linux/clk/ti.h
index 7f58f11..e0a2d32 100644
--- a/include/linux/clk/ti.h
+++ b/include/linux/clk/ti.h
@@ -132,6 +132,33 @@ struct clk_hw_omap {
const struct clk_hw_omap_ops *ops;
};
+/*
+ * struct clk_hw_omap.flags possibilities
+ *
+ * XXX document the rest of the clock flags here
+ *
+ * ENABLE_REG_32BIT: (OMAP1 only) clock control register must be accessed
+ * with 32bit ops, by default OMAP1 uses 16bit ops.
+ * CLOCK_IDLE_CONTROL: (OMAP1 only) clock has autoidle support.
+ * CLOCK_NO_IDLE_PARENT: (OMAP1 only) when clock is enabled, its parent
+ * clock is put to no-idle mode.
+ * ENABLE_ON_INIT: Clock is enabled on init.
+ * INVERT_ENABLE: By default, clock enable bit behavior is '1' enable, '0'
+ * disable. This inverts the behavior making '0' enable and '1' disable.
+ * CLOCK_CLKOUTX2: (OMAP4 only) DPLL CLKOUT and CLKOUTX2 GATE_CTRL
+ * bits share the same register. This flag allows the
+ * omap4_dpllmx*() code to determine which GATE_CTRL bit field
+ * should be used. This is a temporary solution - a better approach
+ * would be to associate clock type-specific data with the clock,
+ * similar to the struct dpll_data approach.
+ */
+#define ENABLE_REG_32BIT (1 << 0) /* Use 32-bit access */
+#define CLOCK_IDLE_CONTROL (1 << 1)
+#define CLOCK_NO_IDLE_PARENT (1 << 2)
+#define ENABLE_ON_INIT (1 << 3) /* Enable upon framework init */
+#define INVERT_ENABLE (1 << 4) /* 0 enables, 1 disables */
+#define CLOCK_CLKOUTX2 (1 << 5)
+
/* CM_CLKEN_PLL*.EN* bit values - not all are available for every DPLL */
#define DPLL_LOW_POWER_STOP 0x1
#define DPLL_LOW_POWER_BYPASS 0x5
@@ -176,8 +203,13 @@ long omap2_dpll_round_rate(struct clk_hw *hw, unsigned long target_rate,
void omap2_init_clk_clkdm(struct clk_hw *clk);
unsigned long omap3_clkoutx2_recalc(struct clk_hw *hw,
unsigned long parent_rate);
+int omap2_clkops_enable_clkdm(struct clk_hw *hw);
+void omap2_clkops_disable_clkdm(struct clk_hw *hw);
int omap3_dpll4_set_rate(struct clk_hw *clk, unsigned long rate,
unsigned long parent_rate);
+int omap2_dflt_clk_enable(struct clk_hw *hw);
+void omap2_dflt_clk_disable(struct clk_hw *hw);
+int omap2_dflt_clk_is_enabled(struct clk_hw *hw);
void ti_dt_clocks_register(struct ti_dt_clk *oclks);
void of_ti_autoidle_setup(struct device_node *node);
@@ -194,5 +226,8 @@ 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_omap3430es2_dss_usbhost_wait;
+extern const struct clk_hw_omap_ops clkhwops_am35xx_ipss_module_wait;
#endif
--
1.7.9.5
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