// SPDX-License-Identifier: GPL-2.0-only
/*
* AM33XX CM functions
*
* Copyright (C) 2011-2012 Texas Instruments Incorporated - https://www.ti.com/
* Vaibhav Hiremath <[email protected]>
*
* Reference taken from OMAP4 cminst44xx.c
*/
#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.va + 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.va + 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_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)
* @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, 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)
* @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, u16 clkctrl_offs)
{
u32 v;
v = _clkctrl_idlest(inst, 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.
*/
static 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.
*/
static 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.
*/
static 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.
*/
static 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.
*/
static 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
* @part: PRCM partition, ignored for AM33xx
* @inst: CM instance register offset (*_INST macro)
* @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
* @bit_shift: bit shift for the register, ignored for AM33xx
*
* 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"
*/
static int am33xx_cm_wait_module_ready(u8 part, s16 inst, u16 clkctrl_offs,
u8 bit_shift)
{
int i = 0;
omap_test_timeout(_is_module_ready(inst, 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
* @part: CM partition, ignored for AM33xx
* @inst: CM instance register offset (*_INST macro)
* @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
* @bit_shift: bit shift for the register, ignored for AM33xx
*
* 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.
*/
static int am33xx_cm_wait_module_idle(u8 part, s16 inst, u16 clkctrl_offs,
u8 bit_shift)
{
int i = 0;
omap_test_timeout((_clkctrl_idlest(inst, 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)
* @part: CM partition, ignored for AM33xx
* @inst: CM instance register offset (*_INST macro)
* @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
*
* No return value.
*/
static void am33xx_cm_module_enable(u8 mode, u8 part, u16 inst,
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
* @part: CM partition, ignored for AM33xx
* @inst: CM instance register offset (*_INST macro)
* @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro)
*
* No return value.
*/
static void am33xx_cm_module_disable(u8 part, u16 inst, 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;
}
static u32 am33xx_cm_xlate_clkctrl(u8 part, u16 inst, u16 offset)
{
return cm_base.pa + inst + offset;
}
/**
* am33xx_clkdm_save_context - Save the clockdomain transition context
* @clkdm: The clockdomain pointer whose context needs to be saved
*
* Save the clockdomain transition context.
*/
static int am33xx_clkdm_save_context(struct clockdomain *clkdm)
{
clkdm->context = am33xx_cm_read_reg_bits(clkdm->cm_inst,
clkdm->clkdm_offs,
AM33XX_CLKTRCTRL_MASK);
return 0;
}
/**
* am33xx_clkdm_restore_context - Restore the clockdomain transition context
* @clkdm: The clockdomain pointer whose context needs to be restored
*
* Restore the clockdomain transition context.
*/
static int am33xx_clkdm_restore_context(struct clockdomain *clkdm)
{
switch (clkdm->context) {
case OMAP34XX_CLKSTCTRL_DISABLE_AUTO:
am33xx_clkdm_deny_idle(clkdm);
break;
case OMAP34XX_CLKSTCTRL_FORCE_SLEEP:
am33xx_clkdm_sleep(clkdm);
break;
case OMAP34XX_CLKSTCTRL_FORCE_WAKEUP:
am33xx_clkdm_wakeup(clkdm);
break;
case OMAP34XX_CLKSTCTRL_ENABLE_AUTO:
am33xx_clkdm_allow_idle(clkdm);
break;
}
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,
.clkdm_save_context = am33xx_clkdm_save_context,
.clkdm_restore_context = am33xx_clkdm_restore_context,
};
static const struct cm_ll_data am33xx_cm_ll_data = {
.wait_module_ready = &am33xx_cm_wait_module_ready,
.wait_module_idle = &am33xx_cm_wait_module_idle,
.module_enable = &am33xx_cm_module_enable,
.module_disable = &am33xx_cm_module_disable,
.xlate_clkctrl = &am33xx_cm_xlate_clkctrl,
};
int __init am33xx_cm_init(const struct omap_prcm_init_data *data)
{
return cm_register(&am33xx_cm_ll_data);
}
static void __exit am33xx_cm_exit(void)
{
cm_unregister(&am33xx_cm_ll_data);
}
__exitcall(am33xx_cm_exit);
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