diff options
Diffstat (limited to 'drivers/clk/ti/gate.c')
| -rw-r--r-- | drivers/clk/ti/gate.c | 249 | 
1 files changed, 249 insertions, 0 deletions
diff --git a/drivers/clk/ti/gate.c b/drivers/clk/ti/gate.c new file mode 100644 index 00000000000..b326d2797fe --- /dev/null +++ b/drivers/clk/ti/gate.c @@ -0,0 +1,249 @@ +/* + * OMAP gate clock 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> + +#define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw) + +#undef pr_fmt +#define pr_fmt(fmt) "%s: " fmt, __func__ + +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 = ti_clk_ll_ops->clk_readl(parent->reg); +		dummy_v = orig_v; + +		/* Write any other value different from the Read value */ +		dummy_v ^= (1 << parent->shift); +		ti_clk_ll_ops->clk_writel(dummy_v, parent->reg); + +		/* Write the original divider */ +		ti_clk_ll_ops->clk_writel(orig_v, parent->reg); +	} + +	return ret; +} + +static void __init _of_ti_gate_clk_setup(struct device_node *node, +					 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) +		return; + +	clk_hw->hw.init = &init; + +	init.name = clk_name; +	init.ops = ops; + +	if (ops != &omap_gate_clkdm_clk_ops) { +		clk_hw->enable_reg = ti_clk_get_reg_addr(node, 0); +		if (!clk_hw->enable_reg) +			goto cleanup; + +		if (!of_property_read_u32(node, "ti,bit-shift", &val)) +			clk_hw->enable_bit = val; +	} + +	clk_hw->ops = hw_ops; + +	clk_hw->flags = MEMMAP_ADDRESSING; + +	if (of_clk_get_parent_count(node) != 1) { +		pr_err("%s must have 1 parent\n", clk_name); +		goto cleanup; +	} + +	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); +		return; +	} + +cleanup: +	kfree(clk_hw); +} + +static void __init +_of_ti_composite_gate_clk_setup(struct device_node *node, +				const struct clk_hw_omap_ops *hw_ops) +{ +	struct clk_hw_omap *gate; +	u32 val = 0; + +	gate = kzalloc(sizeof(*gate), GFP_KERNEL); +	if (!gate) +		return; + +	gate->enable_reg = ti_clk_get_reg_addr(node, 0); +	if (!gate->enable_reg) +		goto cleanup; + +	of_property_read_u32(node, "ti,bit-shift", &val); + +	gate->enable_bit = val; +	gate->ops = hw_ops; +	gate->flags = MEMMAP_ADDRESSING; + +	if (!ti_clk_add_component(node, &gate->hw, CLK_COMPONENT_TYPE_GATE)) +		return; + +cleanup: +	kfree(gate); +} + +static void __init +of_ti_composite_no_wait_gate_clk_setup(struct device_node *node) +{ +	_of_ti_composite_gate_clk_setup(node, NULL); +} +CLK_OF_DECLARE(ti_composite_no_wait_gate_clk, "ti,composite-no-wait-gate-clock", +	       of_ti_composite_no_wait_gate_clk_setup); + +#if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3) +static void __init of_ti_composite_interface_clk_setup(struct device_node *node) +{ +	_of_ti_composite_gate_clk_setup(node, &clkhwops_iclk_wait); +} +CLK_OF_DECLARE(ti_composite_interface_clk, "ti,composite-interface-clock", +	       of_ti_composite_interface_clk_setup); +#endif + +static void __init of_ti_composite_gate_clk_setup(struct device_node *node) +{ +	_of_ti_composite_gate_clk_setup(node, &clkhwops_wait); +} +CLK_OF_DECLARE(ti_composite_gate_clk, "ti,composite-gate-clock", +	       of_ti_composite_gate_clk_setup); + + +static void __init of_ti_clkdm_gate_clk_setup(struct device_node *node) +{ +	_of_ti_gate_clk_setup(node, &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) +{ +	_of_ti_gate_clk_setup(node, &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) +{ +	_of_ti_gate_clk_setup(node, &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) +{ +	_of_ti_gate_clk_setup(node, &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) +{ +	_of_ti_gate_clk_setup(node, &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) +{ +	_of_ti_gate_clk_setup(node, &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  | 
