diff options
Diffstat (limited to 'arch/arm/mach-omap2/cm33xx.c')
| -rw-r--r-- | arch/arm/mach-omap2/cm33xx.c | 364 | 
1 files changed, 364 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/cm33xx.c b/arch/arm/mach-omap2/cm33xx.c new file mode 100644 index 00000000000..b3f99e93def --- /dev/null +++ b/arch/arm/mach-omap2/cm33xx.c @@ -0,0 +1,364 @@ +/* + * AM33XX CM functions + * + * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/ + * Vaibhav Hiremath <hvaibhav@ti.com> + * + * Reference taken from from OMAP4 cminst44xx.c + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * 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/kernel.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/io.h> + +#include "clockdomain.h" +#include "cm.h" +#include "cm33xx.h" +#include "cm-regbits-34xx.h" +#include "cm-regbits-33xx.h" +#include "prm33xx.h" + +/* + * CLKCTRL_IDLEST_*: possible values for the CM_*_CLKCTRL.IDLEST bitfield: + * + *   0x0 func:     Module is fully functional, including OCP + *   0x1 trans:    Module is performing transition: wakeup, or sleep, or sleep + *                 abortion + *   0x2 idle:     Module is in Idle mode (only OCP part). It is functional if + *                 using separate functional clock + *   0x3 disabled: Module is disabled and cannot be accessed + * + */ +#define CLKCTRL_IDLEST_FUNCTIONAL		0x0 +#define CLKCTRL_IDLEST_INTRANSITION		0x1 +#define CLKCTRL_IDLEST_INTERFACE_IDLE		0x2 +#define CLKCTRL_IDLEST_DISABLED			0x3 + +/* Private functions */ + +/* Read a register in a CM instance */ +static inline u32 am33xx_cm_read_reg(u16 inst, u16 idx) +{ +	return readl_relaxed(cm_base + inst + idx); +} + +/* Write into a register in a CM */ +static inline void am33xx_cm_write_reg(u32 val, u16 inst, u16 idx) +{ +	writel_relaxed(val, cm_base + inst + idx); +} + +/* Read-modify-write a register in CM */ +static inline u32 am33xx_cm_rmw_reg_bits(u32 mask, u32 bits, s16 inst, s16 idx) +{ +	u32 v; + +	v = am33xx_cm_read_reg(inst, idx); +	v &= ~mask; +	v |= bits; +	am33xx_cm_write_reg(v, inst, idx); + +	return v; +} + +static inline u32 am33xx_cm_set_reg_bits(u32 bits, s16 inst, s16 idx) +{ +	return am33xx_cm_rmw_reg_bits(bits, bits, inst, idx); +} + +static inline u32 am33xx_cm_clear_reg_bits(u32 bits, s16 inst, s16 idx) +{ +	return am33xx_cm_rmw_reg_bits(bits, 0x0, inst, idx); +} + +static inline u32 am33xx_cm_read_reg_bits(u16 inst, s16 idx, u32 mask) +{ +	u32 v; + +	v = am33xx_cm_read_reg(inst, idx); +	v &= mask; +	v >>= __ffs(mask); + +	return v; +} + +/** + * _clkctrl_idlest - read a CM_*_CLKCTRL register; mask & shift IDLEST bitfield + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) + * + * Return the IDLEST bitfield of a CM_*_CLKCTRL register, shifted down to + * bit 0. + */ +static u32 _clkctrl_idlest(u16 inst, s16 cdoffs, u16 clkctrl_offs) +{ +	u32 v = am33xx_cm_read_reg(inst, clkctrl_offs); +	v &= AM33XX_IDLEST_MASK; +	v >>= AM33XX_IDLEST_SHIFT; +	return v; +} + +/** + * _is_module_ready - can module registers be accessed without causing an abort? + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) + * + * Returns true if the module's CM_*_CLKCTRL.IDLEST bitfield is either + * *FUNCTIONAL or *INTERFACE_IDLE; false otherwise. + */ +static bool _is_module_ready(u16 inst, s16 cdoffs, u16 clkctrl_offs) +{ +	u32 v; + +	v = _clkctrl_idlest(inst, cdoffs, clkctrl_offs); + +	return (v == CLKCTRL_IDLEST_FUNCTIONAL || +		v == CLKCTRL_IDLEST_INTERFACE_IDLE) ? true : false; +} + +/** + * _clktrctrl_write - write @c to a CM_CLKSTCTRL.CLKTRCTRL register bitfield + * @c: CLKTRCTRL register bitfield (LSB = bit 0, i.e., unshifted) + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * + * @c must be the unshifted value for CLKTRCTRL - i.e., this function + * will handle the shift itself. + */ +static void _clktrctrl_write(u8 c, u16 inst, u16 cdoffs) +{ +	u32 v; + +	v = am33xx_cm_read_reg(inst, cdoffs); +	v &= ~AM33XX_CLKTRCTRL_MASK; +	v |= c << AM33XX_CLKTRCTRL_SHIFT; +	am33xx_cm_write_reg(v, inst, cdoffs); +} + +/* Public functions */ + +/** + * am33xx_cm_is_clkdm_in_hwsup - is a clockdomain in hwsup idle mode? + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * + * Returns true if the clockdomain referred to by (@inst, @cdoffs) + * is in hardware-supervised idle mode, or 0 otherwise. + */ +bool am33xx_cm_is_clkdm_in_hwsup(u16 inst, u16 cdoffs) +{ +	u32 v; + +	v = am33xx_cm_read_reg(inst, cdoffs); +	v &= AM33XX_CLKTRCTRL_MASK; +	v >>= AM33XX_CLKTRCTRL_SHIFT; + +	return (v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ? true : false; +} + +/** + * am33xx_cm_clkdm_enable_hwsup - put a clockdomain in hwsup-idle mode + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * + * Put a clockdomain referred to by (@inst, @cdoffs) into + * hardware-supervised idle mode.  No return value. + */ +void am33xx_cm_clkdm_enable_hwsup(u16 inst, u16 cdoffs) +{ +	_clktrctrl_write(OMAP34XX_CLKSTCTRL_ENABLE_AUTO, inst, cdoffs); +} + +/** + * am33xx_cm_clkdm_disable_hwsup - put a clockdomain in swsup-idle mode + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * + * Put a clockdomain referred to by (@inst, @cdoffs) into + * software-supervised idle mode, i.e., controlled manually by the + * Linux OMAP clockdomain code.  No return value. + */ +void am33xx_cm_clkdm_disable_hwsup(u16 inst, u16 cdoffs) +{ +	_clktrctrl_write(OMAP34XX_CLKSTCTRL_DISABLE_AUTO, inst, cdoffs); +} + +/** + * am33xx_cm_clkdm_force_sleep - try to put a clockdomain into idle + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * + * Put a clockdomain referred to by (@inst, @cdoffs) into idle + * No return value. + */ +void am33xx_cm_clkdm_force_sleep(u16 inst, u16 cdoffs) +{ +	_clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_SLEEP, inst, cdoffs); +} + +/** + * am33xx_cm_clkdm_force_wakeup - try to take a clockdomain out of idle + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * + * Take a clockdomain referred to by (@inst, @cdoffs) out of idle, + * waking it up.  No return value. + */ +void am33xx_cm_clkdm_force_wakeup(u16 inst, u16 cdoffs) +{ +	_clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_WAKEUP, inst, cdoffs); +} + +/* + * + */ + +/** + * am33xx_cm_wait_module_ready - wait for a module to be in 'func' state + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) + * + * Wait for the module IDLEST to be functional. If the idle state is in any + * the non functional state (trans, idle or disabled), module and thus the + * sysconfig cannot be accessed and will probably lead to an "imprecise + * external abort" + */ +int am33xx_cm_wait_module_ready(u16 inst, s16 cdoffs, u16 clkctrl_offs) +{ +	int i = 0; + +	omap_test_timeout(_is_module_ready(inst, cdoffs, clkctrl_offs), +			  MAX_MODULE_READY_TIME, i); + +	return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY; +} + +/** + * am33xx_cm_wait_module_idle - wait for a module to be in 'disabled' + * state + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) + * + * Wait for the module IDLEST to be disabled. Some PRCM transition, + * like reset assertion or parent clock de-activation must wait the + * module to be fully disabled. + */ +int am33xx_cm_wait_module_idle(u16 inst, s16 cdoffs, u16 clkctrl_offs) +{ +	int i = 0; + +	if (!clkctrl_offs) +		return 0; + +	omap_test_timeout((_clkctrl_idlest(inst, cdoffs, clkctrl_offs) == +				CLKCTRL_IDLEST_DISABLED), +				MAX_MODULE_READY_TIME, i); + +	return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY; +} + +/** + * am33xx_cm_module_enable - Enable the modulemode inside CLKCTRL + * @mode: Module mode (SW or HW) + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) + * + * No return value. + */ +void am33xx_cm_module_enable(u8 mode, u16 inst, s16 cdoffs, u16 clkctrl_offs) +{ +	u32 v; + +	v = am33xx_cm_read_reg(inst, clkctrl_offs); +	v &= ~AM33XX_MODULEMODE_MASK; +	v |= mode << AM33XX_MODULEMODE_SHIFT; +	am33xx_cm_write_reg(v, inst, clkctrl_offs); +} + +/** + * am33xx_cm_module_disable - Disable the module inside CLKCTRL + * @inst: CM instance register offset (*_INST macro) + * @cdoffs: Clockdomain register offset (*_CDOFFS macro) + * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) + * + * No return value. + */ +void am33xx_cm_module_disable(u16 inst, s16 cdoffs, u16 clkctrl_offs) +{ +	u32 v; + +	v = am33xx_cm_read_reg(inst, clkctrl_offs); +	v &= ~AM33XX_MODULEMODE_MASK; +	am33xx_cm_write_reg(v, inst, clkctrl_offs); +} + +/* + * Clockdomain low-level functions + */ + +static int am33xx_clkdm_sleep(struct clockdomain *clkdm) +{ +	am33xx_cm_clkdm_force_sleep(clkdm->cm_inst, clkdm->clkdm_offs); +	return 0; +} + +static int am33xx_clkdm_wakeup(struct clockdomain *clkdm) +{ +	am33xx_cm_clkdm_force_wakeup(clkdm->cm_inst, clkdm->clkdm_offs); +	return 0; +} + +static void am33xx_clkdm_allow_idle(struct clockdomain *clkdm) +{ +	am33xx_cm_clkdm_enable_hwsup(clkdm->cm_inst, clkdm->clkdm_offs); +} + +static void am33xx_clkdm_deny_idle(struct clockdomain *clkdm) +{ +	am33xx_cm_clkdm_disable_hwsup(clkdm->cm_inst, clkdm->clkdm_offs); +} + +static int am33xx_clkdm_clk_enable(struct clockdomain *clkdm) +{ +	if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) +		return am33xx_clkdm_wakeup(clkdm); + +	return 0; +} + +static int am33xx_clkdm_clk_disable(struct clockdomain *clkdm) +{ +	bool hwsup = false; + +	hwsup = am33xx_cm_is_clkdm_in_hwsup(clkdm->cm_inst, clkdm->clkdm_offs); + +	if (!hwsup && (clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) +		am33xx_clkdm_sleep(clkdm); + +	return 0; +} + +struct clkdm_ops am33xx_clkdm_operations = { +	.clkdm_sleep		= am33xx_clkdm_sleep, +	.clkdm_wakeup		= am33xx_clkdm_wakeup, +	.clkdm_allow_idle	= am33xx_clkdm_allow_idle, +	.clkdm_deny_idle	= am33xx_clkdm_deny_idle, +	.clkdm_clk_enable	= am33xx_clkdm_clk_enable, +	.clkdm_clk_disable	= am33xx_clkdm_clk_disable, +};  | 
