diff options
| -rw-r--r-- | Documentation/devicetree/bindings/clock/ti/autoidle.txt | 39 | ||||
| -rw-r--r-- | arch/arm/mach-omap2/clock.c | 6 | ||||
| -rw-r--r-- | drivers/clk/ti/Makefile | 2 | ||||
| -rw-r--r-- | drivers/clk/ti/autoidle.c | 133 | ||||
| -rw-r--r-- | include/linux/clk/ti.h | 9 |
5 files changed, 188 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/clock/ti/autoidle.txt b/Documentation/devicetree/bindings/clock/ti/autoidle.txt new file mode 100644 index 000000000000..7c735dde9fe9 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/ti/autoidle.txt @@ -0,0 +1,39 @@ +Binding for Texas Instruments autoidle 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 +clock which can be put to idle automatically by hardware based on the usage +and a configuration bit setting. Autoidle clock is never an individual +clock, it is always a derivative of some basic clock like a gate, divider, +or fixed-factor. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- reg : offset for the register controlling the autoidle +- ti,autoidle-shift : bit shift of the autoidle enable bit +- ti,invert-autoidle-bit : autoidle is enabled by setting the bit to 0 + +Examples: + dpll_core_m4_ck: dpll_core_m4_ck { + #clock-cells = <0>; + compatible = "ti,divider-clock"; + clocks = <&dpll_core_x2_ck>; + ti,max-div = <31>; + ti,autoidle-shift = <8>; + reg = <0x2d38>; + ti,index-starts-at-one; + ti,invert-autoidle-bit; + }; + + dpll_usb_clkdcoldo_ck: dpll_usb_clkdcoldo_ck { + #clock-cells = <0>; + compatible = "ti,fixed-factor-clock"; + clocks = <&dpll_usb_ck>; + ti,clock-div = <1>; + ti,autoidle-shift = <8>; + reg = <0x01b4>; + ti,clock-mult = <1>; + ti,invert-autoidle-bit; + }; diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c index c7c5d31e9082..238be3f1ddce 100644 --- a/arch/arm/mach-omap2/clock.c +++ b/arch/arm/mach-omap2/clock.c @@ -520,6 +520,9 @@ int omap2_clk_enable_autoidle_all(void) list_for_each_entry(c, &clk_hw_omap_clocks, node) if (c->ops && c->ops->allow_idle) c->ops->allow_idle(c); + + of_ti_clk_allow_autoidle_all(); + return 0; } @@ -539,6 +542,9 @@ int omap2_clk_disable_autoidle_all(void) list_for_each_entry(c, &clk_hw_omap_clocks, node) if (c->ops && c->ops->deny_idle) c->ops->deny_idle(c); + + of_ti_clk_deny_autoidle_all(); + return 0; } diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile index 3dbb78dc9fca..7fa1a48df4f3 100644 --- a/drivers/clk/ti/Makefile +++ b/drivers/clk/ti/Makefile @@ -1,4 +1,4 @@ ifneq ($(CONFIG_OF),) -obj-y += clk.o +obj-y += clk.o autoidle.o clk-common = dpll.o endif diff --git a/drivers/clk/ti/autoidle.c b/drivers/clk/ti/autoidle.c new file mode 100644 index 000000000000..8912ff80af34 --- /dev/null +++ b/drivers/clk/ti/autoidle.c @@ -0,0 +1,133 @@ +/* + * TI clock autoidle support + * + * Copyright (C) 2013 Texas Instruments, Inc. + * + * Tero Kristo <t-kristo@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> + +struct clk_ti_autoidle { + void __iomem *reg; + u8 shift; + u8 flags; + const char *name; + struct list_head node; +}; + +#define AUTOIDLE_LOW 0x1 + +static LIST_HEAD(autoidle_clks); + +static void ti_allow_autoidle(struct clk_ti_autoidle *clk) +{ + u32 val; + + val = ti_clk_ll_ops->clk_readl(clk->reg); + + if (clk->flags & AUTOIDLE_LOW) + val &= ~(1 << clk->shift); + else + val |= (1 << clk->shift); + + ti_clk_ll_ops->clk_writel(val, clk->reg); +} + +static void ti_deny_autoidle(struct clk_ti_autoidle *clk) +{ + u32 val; + + val = ti_clk_ll_ops->clk_readl(clk->reg); + + if (clk->flags & AUTOIDLE_LOW) + val |= (1 << clk->shift); + else + val &= ~(1 << clk->shift); + + ti_clk_ll_ops->clk_writel(val, clk->reg); +} + +/** + * of_ti_clk_allow_autoidle_all - enable autoidle for all clocks + * + * Enables hardware autoidle for all registered DT clocks, which have + * the feature. + */ +void of_ti_clk_allow_autoidle_all(void) +{ + struct clk_ti_autoidle *c; + + list_for_each_entry(c, &autoidle_clks, node) + ti_allow_autoidle(c); +} + +/** + * of_ti_clk_deny_autoidle_all - disable autoidle for all clocks + * + * Disables hardware autoidle for all registered DT clocks, which have + * the feature. + */ +void of_ti_clk_deny_autoidle_all(void) +{ + struct clk_ti_autoidle *c; + + list_for_each_entry(c, &autoidle_clks, node) + ti_deny_autoidle(c); +} + +/** + * of_ti_clk_autoidle_setup - sets up hardware autoidle for a clock + * @node: pointer to the clock device node + * + * Checks if a clock has hardware autoidle support or not (check + * for presence of 'ti,autoidle-shift' property in the device tree + * node) and sets up the hardware autoidle feature for the clock + * if available. If autoidle is available, the clock is also added + * to the autoidle list for later processing. Returns 0 on success, + * negative error value on failure. + */ +int __init of_ti_clk_autoidle_setup(struct device_node *node) +{ + u32 shift; + struct clk_ti_autoidle *clk; + + /* Check if this clock has autoidle support or not */ + if (of_property_read_u32(node, "ti,autoidle-shift", &shift)) + return 0; + + clk = kzalloc(sizeof(*clk), GFP_KERNEL); + + if (!clk) + return -ENOMEM; + + clk->shift = shift; + clk->name = node->name; + clk->reg = ti_clk_get_reg_addr(node, 0); + + if (!clk->reg) { + kfree(clk); + return -EINVAL; + } + + if (of_property_read_bool(node, "ti,invert-autoidle-bit")) + clk->flags |= AUTOIDLE_LOW; + + list_add(&clk->node, &autoidle_clks); + + return 0; +} diff --git a/include/linux/clk/ti.h b/include/linux/clk/ti.h index 3f9de3973582..ca38ee3620b1 100644 --- a/include/linux/clk/ti.h +++ b/include/linux/clk/ti.h @@ -242,6 +242,15 @@ void ti_dt_clocks_register(struct ti_dt_clk *oclks); void ti_dt_clk_init_provider(struct device_node *np, int index); int ti_clk_retry_init(struct device_node *node, struct clk_hw *hw, ti_of_clk_init_cb_t func); +int of_ti_clk_autoidle_setup(struct device_node *node); + +#ifdef CONFIG_OF +void of_ti_clk_allow_autoidle_all(void); +void of_ti_clk_deny_autoidle_all(void); +#else +static inline void of_ti_clk_allow_autoidle_all(void) { } +static inline void of_ti_clk_deny_autoidle_all(void) { } +#endif extern const struct clk_hw_omap_ops clkhwops_omap3_dpll; extern const struct clk_hw_omap_ops clkhwops_omap4_dpllmx; |