From b1a07b478b63f0a8f971b3a82ce34a67a9324547 Mon Sep 17 00:00:00 2001 From: Tero Kristo Date: Tue, 18 Jun 2013 16:27:57 +0300 Subject: CLK: TI: add autoidle support TI clk driver now routes some of the basic clocks through own registration routine to allow autoidle support. This routine just checks a couple of device node properties and adds autoidle support if required, and just passes the registration forward to basic clocks. Signed-off-by: Tero Kristo Acked-by: Tony Lindgren Signed-off-by: Mike Turquette --- drivers/clk/ti/Makefile | 2 +- drivers/clk/ti/autoidle.c | 133 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 134 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/ti/autoidle.c (limited to 'drivers') diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile index 3dbb78d..7fa1a48 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 0000000..8912ff8 --- /dev/null +++ b/drivers/clk/ti/autoidle.c @@ -0,0 +1,133 @@ +/* + * TI clock autoidle 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 +#include + +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; +} -- cgit v1.1