From 3cd4a596224565cff00b69a02d4b5fa7432ea6d3 Mon Sep 17 00:00:00 2001 From: Tero Kristo Date: Wed, 21 Aug 2013 19:39:15 +0300 Subject: [PATCH] CLK: TI: add support for clockdomain binding Some OMAP clocks require knowledge about their parent clockdomain for book keeping purposes. This patch creates a new DT binding for TI clockdomains, which act as a collection of device clocks. Clockdomain itself is rather misleading name for the hardware functionality, as at least on OMAP4 / OMAP5 / DRA7 the clockdomains can be collections of either clocks and/or IP blocks, thus idle-domain or such might be more appropriate. For most cases on these SoCs, the kernel doesn't even need the information and the mappings can be ignored. Signed-off-by: Tero Kristo Acked-by: Tony Lindgren Signed-off-by: Mike Turquette --- .../bindings/clock/ti/clockdomain.txt | 24 +++++++ drivers/clk/ti/Makefile | 2 +- drivers/clk/ti/clockdomain.c | 70 +++++++++++++++++++ include/linux/clk/ti.h | 1 + 4 files changed, 96 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/clock/ti/clockdomain.txt create mode 100644 drivers/clk/ti/clockdomain.c diff --git a/Documentation/devicetree/bindings/clock/ti/clockdomain.txt b/Documentation/devicetree/bindings/clock/ti/clockdomain.txt new file mode 100644 index 000000000000..cb76b3f2b341 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/ti/clockdomain.txt @@ -0,0 +1,24 @@ +Binding for Texas Instruments clockdomain. + +Binding status: Unstable - ABI compatibility may be broken in the future + +This binding uses the common clock binding[1] in consumer role. +Every clock on TI SoC belongs to one clockdomain, but software +only needs this information for specific clocks which require +their parent clockdomain to be controlled when the clock is +enabled/disabled. This binding doesn't define a new clock +binding type, it is used to group existing clock nodes under +hardware hierarchy. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- compatible : shall be "ti,clockdomain" +- #clock-cells : from common clock binding; shall be set to 0. +- clocks : link phandles of clocks within this domain + +Examples: + dss_clkdm: dss_clkdm { + compatible = "ti,clockdomain"; + clocks = <&dss1_alwon_fck_3430es2>, <&dss_ick_3430es2>; + }; diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile index eaa6dc0aeb75..ae7cd1e91cd2 100644 --- a/drivers/clk/ti/Makefile +++ b/drivers/clk/ti/Makefile @@ -1,5 +1,5 @@ ifneq ($(CONFIG_OF),) -obj-y += clk.o autoidle.o +obj-y += clk.o autoidle.o clockdomain.o clk-common = dpll.o composite.o divider.o gate.o \ fixed-factor.o endif diff --git a/drivers/clk/ti/clockdomain.c b/drivers/clk/ti/clockdomain.c new file mode 100644 index 000000000000..f1e0038d76ac --- /dev/null +++ b/drivers/clk/ti/clockdomain.c @@ -0,0 +1,70 @@ +/* + * OMAP clockdomain support + * + * Copyright (C) 2013 Texas Instruments, Inc. + * + * Tero Kristo + * + * 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 +#include +#include +#include +#include + +#undef pr_fmt +#define pr_fmt(fmt) "%s: " fmt, __func__ + +static void __init of_ti_clockdomain_setup(struct device_node *node) +{ + struct clk *clk; + struct clk_hw *clk_hw; + const char *clkdm_name = node->name; + int i; + int num_clks; + + num_clks = of_count_phandle_with_args(node, "clocks", "#clock-cells"); + + for (i = 0; i < num_clks; i++) { + clk = of_clk_get(node, i); + if (__clk_get_flags(clk) & CLK_IS_BASIC) { + pr_warn("can't setup clkdm for basic clk %s\n", + __clk_get_name(clk)); + continue; + } + clk_hw = __clk_get_hw(clk); + to_clk_hw_omap(clk_hw)->clkdm_name = clkdm_name; + omap2_init_clk_clkdm(clk_hw); + } +} + +static struct of_device_id ti_clkdm_match_table[] __initdata = { + { .compatible = "ti,clockdomain" }, + { } +}; + +/** + * ti_dt_clockdomains_setup - setup device tree clockdomains + * + * Initializes clockdomain nodes for a SoC. This parses through all the + * nodes with compatible = "ti,clockdomain", and add the clockdomain + * info for all the clocks listed under these. This function shall be + * called after rest of the DT clock init has completed and all + * clock nodes have been registered. + */ +void __init ti_dt_clockdomains_setup(void) +{ + struct device_node *np; + for_each_matching_node(np, ti_clkdm_match_table) { + of_ti_clockdomain_setup(np); + } +} diff --git a/include/linux/clk/ti.h b/include/linux/clk/ti.h index d94feb3b5519..a3f89a60de07 100644 --- a/include/linux/clk/ti.h +++ b/include/linux/clk/ti.h @@ -255,6 +255,7 @@ int omap2_dflt_clk_is_enabled(struct clk_hw *hw); void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index); void ti_dt_clocks_register(struct ti_dt_clk *oclks); void ti_dt_clk_init_provider(struct device_node *np, int index); +void ti_dt_clockdomains_setup(void); 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); -- 2.20.1