linux/arch/arm/mach-omap2/clockdomain.c
Paul Walmsley f38ca10a79 OMAP2 PRCM: convert OMAP2 PRCM macros to the _SHIFT/_MASK suffixes
Fix all of the remaining OMAP2 PRCM register shift/bitmask macros that
did not use the _SHIFT/_MASK suffixes to use them.  This makes the use
of these macros consistent.  It is intended to reduce error, as code
can be inspected visually by reviewers to ensure that bitshifts and
bitmasks are used in the appropriate places.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
2010-05-20 12:31:04 -06:00

1074 lines
29 KiB
C

/*
* OMAP2/3/4 clockdomain framework functions
*
* Copyright (C) 2008-2010 Texas Instruments, Inc.
* Copyright (C) 2008-2010 Nokia Corporation
*
* Written by Paul Walmsley and Jouni Högander
* Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@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.
*/
#undef DEBUG
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/limits.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/bitops.h>
#include "prm.h"
#include "prm-regbits-24xx.h"
#include "cm.h"
#include <plat/clock.h>
#include <plat/powerdomain.h>
#include <plat/clockdomain.h>
#include <plat/prcm.h>
/* clkdm_list contains all registered struct clockdomains */
static LIST_HEAD(clkdm_list);
/* array of clockdomain deps to be added/removed when clkdm in hwsup mode */
static struct clkdm_autodep *autodeps;
/* Private functions */
static struct clockdomain *_clkdm_lookup(const char *name)
{
struct clockdomain *clkdm, *temp_clkdm;
if (!name)
return NULL;
clkdm = NULL;
list_for_each_entry(temp_clkdm, &clkdm_list, node) {
if (!strcmp(name, temp_clkdm->name)) {
clkdm = temp_clkdm;
break;
}
}
return clkdm;
}
/**
* _clkdm_register - register a clockdomain
* @clkdm: struct clockdomain * to register
*
* Adds a clockdomain to the internal clockdomain list.
* Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is
* already registered by the provided name, or 0 upon success.
*/
static int _clkdm_register(struct clockdomain *clkdm)
{
struct powerdomain *pwrdm;
if (!clkdm || !clkdm->name)
return -EINVAL;
if (!omap_chip_is(clkdm->omap_chip))
return -EINVAL;
pwrdm = pwrdm_lookup(clkdm->pwrdm.name);
if (!pwrdm) {
pr_err("clockdomain: %s: powerdomain %s does not exist\n",
clkdm->name, clkdm->pwrdm.name);
return -EINVAL;
}
clkdm->pwrdm.ptr = pwrdm;
/* Verify that the clockdomain is not already registered */
if (_clkdm_lookup(clkdm->name))
return -EEXIST;
list_add(&clkdm->node, &clkdm_list);
pwrdm_add_clkdm(pwrdm, clkdm);
pr_debug("clockdomain: registered %s\n", clkdm->name);
return 0;
}
/* _clkdm_deps_lookup - look up the specified clockdomain in a clkdm list */
static struct clkdm_dep *_clkdm_deps_lookup(struct clockdomain *clkdm,
struct clkdm_dep *deps)
{
struct clkdm_dep *cd;
if (!clkdm || !deps || !omap_chip_is(clkdm->omap_chip))
return ERR_PTR(-EINVAL);
for (cd = deps; cd->clkdm_name; cd++) {
if (!omap_chip_is(cd->omap_chip))
continue;
if (!cd->clkdm && cd->clkdm_name)
cd->clkdm = _clkdm_lookup(cd->clkdm_name);
if (cd->clkdm == clkdm)
break;
}
if (!cd->clkdm_name)
return ERR_PTR(-ENOENT);
return cd;
}
/*
* _autodep_lookup - resolve autodep clkdm names to clkdm pointers; store
* @autodep: struct clkdm_autodep * to resolve
*
* Resolve autodep clockdomain names to clockdomain pointers via
* clkdm_lookup() and store the pointers in the autodep structure. An
* "autodep" is a clockdomain sleep/wakeup dependency that is
* automatically added and removed whenever clocks in the associated
* clockdomain are enabled or disabled (respectively) when the
* clockdomain is in hardware-supervised mode. Meant to be called
* once at clockdomain layer initialization, since these should remain
* fixed for a particular architecture. No return value.
*/
static void _autodep_lookup(struct clkdm_autodep *autodep)
{
struct clockdomain *clkdm;
if (!autodep)
return;
if (!omap_chip_is(autodep->omap_chip))
return;
clkdm = clkdm_lookup(autodep->clkdm.name);
if (!clkdm) {
pr_err("clockdomain: autodeps: clockdomain %s does not exist\n",
autodep->clkdm.name);
clkdm = ERR_PTR(-ENOENT);
}
autodep->clkdm.ptr = clkdm;
}
/*
* _clkdm_add_autodeps - add auto sleepdeps/wkdeps to clkdm upon clock enable
* @clkdm: struct clockdomain *
*
* Add the "autodep" sleep & wakeup dependencies to clockdomain 'clkdm'
* in hardware-supervised mode. Meant to be called from clock framework
* when a clock inside clockdomain 'clkdm' is enabled. No return value.
*/
static void _clkdm_add_autodeps(struct clockdomain *clkdm)
{
struct clkdm_autodep *autodep;
if (!autodeps)
return;
for (autodep = autodeps; autodep->clkdm.ptr; autodep++) {
if (IS_ERR(autodep->clkdm.ptr))
continue;
if (!omap_chip_is(autodep->omap_chip))
continue;
pr_debug("clockdomain: adding %s sleepdep/wkdep for "
"clkdm %s\n", autodep->clkdm.ptr->name,
clkdm->name);
clkdm_add_sleepdep(clkdm, autodep->clkdm.ptr);
clkdm_add_wkdep(clkdm, autodep->clkdm.ptr);
}
}
/*
* _clkdm_add_autodeps - remove auto sleepdeps/wkdeps from clkdm
* @clkdm: struct clockdomain *
*
* Remove the "autodep" sleep & wakeup dependencies from clockdomain 'clkdm'
* in hardware-supervised mode. Meant to be called from clock framework
* when a clock inside clockdomain 'clkdm' is disabled. No return value.
*/
static void _clkdm_del_autodeps(struct clockdomain *clkdm)
{
struct clkdm_autodep *autodep;
if (!autodeps)
return;
for (autodep = autodeps; autodep->clkdm.ptr; autodep++) {
if (IS_ERR(autodep->clkdm.ptr))
continue;
if (!omap_chip_is(autodep->omap_chip))
continue;
pr_debug("clockdomain: removing %s sleepdep/wkdep for "
"clkdm %s\n", autodep->clkdm.ptr->name,
clkdm->name);
clkdm_del_sleepdep(clkdm, autodep->clkdm.ptr);
clkdm_del_wkdep(clkdm, autodep->clkdm.ptr);
}
}
/*
* _omap2_clkdm_set_hwsup - set the hwsup idle transition bit
* @clkdm: struct clockdomain *
* @enable: int 0 to disable, 1 to enable
*
* Internal helper for actually switching the bit that controls hwsup
* idle transitions for clkdm.
*/
static void _omap2_clkdm_set_hwsup(struct clockdomain *clkdm, int enable)
{
u32 bits, v;
if (cpu_is_omap24xx()) {
if (enable)
bits = OMAP24XX_CLKSTCTRL_ENABLE_AUTO;
else
bits = OMAP24XX_CLKSTCTRL_DISABLE_AUTO;
} else if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
if (enable)
bits = OMAP34XX_CLKSTCTRL_ENABLE_AUTO;
else
bits = OMAP34XX_CLKSTCTRL_DISABLE_AUTO;
} else {
BUG();
}
bits = bits << __ffs(clkdm->clktrctrl_mask);
v = __raw_readl(clkdm->clkstctrl_reg);
v &= ~(clkdm->clktrctrl_mask);
v |= bits;
__raw_writel(v, clkdm->clkstctrl_reg);
}
/**
* _init_wkdep_usecount - initialize wkdep usecounts to match hardware
* @clkdm: clockdomain to initialize wkdep usecounts
*
* Initialize the wakeup dependency usecount variables for clockdomain @clkdm.
* If a wakeup dependency is present in the hardware, the usecount will be
* set to 1; otherwise, it will be set to 0. Software should clear all
* software wakeup dependencies prior to calling this function if it wishes
* to ensure that all usecounts start at 0. No return value.
*/
static void _init_wkdep_usecount(struct clockdomain *clkdm)
{
u32 v;
struct clkdm_dep *cd;
if (!clkdm->wkdep_srcs)
return;
for (cd = clkdm->wkdep_srcs; cd->clkdm_name; cd++) {
if (!omap_chip_is(cd->omap_chip))
continue;
if (!cd->clkdm && cd->clkdm_name)
cd->clkdm = _clkdm_lookup(cd->clkdm_name);
if (!cd->clkdm) {
WARN(!cd->clkdm, "clockdomain: %s: wkdep clkdm %s not "
"found\n", clkdm->name, cd->clkdm_name);
continue;
}
v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs,
PM_WKDEP,
(1 << cd->clkdm->dep_bit));
if (v)
pr_debug("clockdomain: %s: wakeup dependency already "
"set to wake up when %s wakes\n",
clkdm->name, cd->clkdm->name);
atomic_set(&cd->wkdep_usecount, (v) ? 1 : 0);
}
}
/**
* _init_sleepdep_usecount - initialize sleepdep usecounts to match hardware
* @clkdm: clockdomain to initialize sleepdep usecounts
*
* Initialize the sleep dependency usecount variables for clockdomain @clkdm.
* If a sleep dependency is present in the hardware, the usecount will be
* set to 1; otherwise, it will be set to 0. Software should clear all
* software sleep dependencies prior to calling this function if it wishes
* to ensure that all usecounts start at 0. No return value.
*/
static void _init_sleepdep_usecount(struct clockdomain *clkdm)
{
u32 v;
struct clkdm_dep *cd;
if (!cpu_is_omap34xx())
return;
if (!clkdm->sleepdep_srcs)
return;
for (cd = clkdm->sleepdep_srcs; cd->clkdm_name; cd++) {
if (!omap_chip_is(cd->omap_chip))
continue;
if (!cd->clkdm && cd->clkdm_name)
cd->clkdm = _clkdm_lookup(cd->clkdm_name);
if (!cd->clkdm) {
WARN(!cd->clkdm, "clockdomain: %s: sleepdep clkdm %s "
"not found\n", clkdm->name, cd->clkdm_name);
continue;
}
v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs,
OMAP3430_CM_SLEEPDEP,
(1 << cd->clkdm->dep_bit));
if (v)
pr_debug("clockdomain: %s: sleep dependency already "
"set to prevent from idling until %s "
"idles\n", clkdm->name, cd->clkdm->name);
atomic_set(&cd->sleepdep_usecount, (v) ? 1 : 0);
}
};
/* Public functions */
/**
* clkdm_init - set up the clockdomain layer
* @clkdms: optional pointer to an array of clockdomains to register
* @init_autodeps: optional pointer to an array of autodeps to register
*
* Set up internal state. If a pointer to an array of clockdomains
* @clkdms was supplied, loop through the list of clockdomains,
* register all that are available on the current platform. Similarly,
* if a pointer to an array of clockdomain autodependencies
* @init_autodeps was provided, register those. No return value.
*/
void clkdm_init(struct clockdomain **clkdms,
struct clkdm_autodep *init_autodeps)
{
struct clockdomain **c = NULL;
struct clockdomain *clkdm;
struct clkdm_autodep *autodep = NULL;
if (clkdms)
for (c = clkdms; *c; c++)
_clkdm_register(*c);
autodeps = init_autodeps;
if (autodeps)
for (autodep = autodeps; autodep->clkdm.ptr; autodep++)
_autodep_lookup(autodep);
/*
* Ensure that the *dep_usecount registers reflect the current
* state of the PRCM.
*/
list_for_each_entry(clkdm, &clkdm_list, node) {
_init_wkdep_usecount(clkdm);
_init_sleepdep_usecount(clkdm);
}
}
/**
* clkdm_lookup - look up a clockdomain by name, return a pointer
* @name: name of clockdomain
*
* Find a registered clockdomain by its name @name. Returns a pointer
* to the struct clockdomain if found, or NULL otherwise.
*/
struct clockdomain *clkdm_lookup(const char *name)
{
struct clockdomain *clkdm, *temp_clkdm;
if (!name)
return NULL;
clkdm = NULL;
list_for_each_entry(temp_clkdm, &clkdm_list, node) {
if (!strcmp(name, temp_clkdm->name)) {
clkdm = temp_clkdm;
break;
}
}
return clkdm;
}
/**
* clkdm_for_each - call function on each registered clockdomain
* @fn: callback function *
*
* Call the supplied function @fn for each registered clockdomain.
* The callback function @fn can return anything but 0 to bail
* out early from the iterator. The callback function is called with
* the clkdm_mutex held, so no clockdomain structure manipulation
* functions should be called from the callback, although hardware
* clockdomain control functions are fine. Returns the last return
* value of the callback function, which should be 0 for success or
* anything else to indicate failure; or -EINVAL if the function pointer
* is null.
*/
int clkdm_for_each(int (*fn)(struct clockdomain *clkdm, void *user),
void *user)
{
struct clockdomain *clkdm;
int ret = 0;
if (!fn)
return -EINVAL;
list_for_each_entry(clkdm, &clkdm_list, node) {
ret = (*fn)(clkdm, user);
if (ret)
break;
}
return ret;
}
/**
* clkdm_get_pwrdm - return a ptr to the pwrdm that this clkdm resides in
* @clkdm: struct clockdomain *
*
* Return a pointer to the struct powerdomain that the specified clockdomain
* @clkdm exists in, or returns NULL if @clkdm is NULL.
*/
struct powerdomain *clkdm_get_pwrdm(struct clockdomain *clkdm)
{
if (!clkdm)
return NULL;
return clkdm->pwrdm.ptr;
}
/* Hardware clockdomain control */
/**
* clkdm_add_wkdep - add a wakeup dependency from clkdm2 to clkdm1
* @clkdm1: wake this struct clockdomain * up (dependent)
* @clkdm2: when this struct clockdomain * wakes up (source)
*
* When the clockdomain represented by @clkdm2 wakes up, wake up
* @clkdm1. Implemented in hardware on the OMAP, this feature is
* designed to reduce wakeup latency of the dependent clockdomain @clkdm1.
* Returns -EINVAL if presented with invalid clockdomain pointers,
* -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or 0 upon
* success.
*/
int clkdm_add_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2)
{
struct clkdm_dep *cd;
if (!clkdm1 || !clkdm2)
return -EINVAL;
cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs);
if (IS_ERR(cd)) {
pr_debug("clockdomain: hardware cannot set/clear wake up of "
"%s when %s wakes up\n", clkdm1->name, clkdm2->name);
return PTR_ERR(cd);
}
if (atomic_inc_return(&cd->wkdep_usecount) == 1) {
pr_debug("clockdomain: hardware will wake up %s when %s wakes "
"up\n", clkdm1->name, clkdm2->name);
prm_set_mod_reg_bits((1 << clkdm2->dep_bit),
clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP);
}
return 0;
}
/**
* clkdm_del_wkdep - remove a wakeup dependency from clkdm2 to clkdm1
* @clkdm1: wake this struct clockdomain * up (dependent)
* @clkdm2: when this struct clockdomain * wakes up (source)
*
* Remove a wakeup dependency causing @clkdm1 to wake up when @clkdm2
* wakes up. Returns -EINVAL if presented with invalid clockdomain
* pointers, -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or
* 0 upon success.
*/
int clkdm_del_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2)
{
struct clkdm_dep *cd;
if (!clkdm1 || !clkdm2)
return -EINVAL;
cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs);
if (IS_ERR(cd)) {
pr_debug("clockdomain: hardware cannot set/clear wake up of "
"%s when %s wakes up\n", clkdm1->name, clkdm2->name);
return PTR_ERR(cd);
}
if (atomic_dec_return(&cd->wkdep_usecount) == 0) {
pr_debug("clockdomain: hardware will no longer wake up %s "
"after %s wakes up\n", clkdm1->name, clkdm2->name);
prm_clear_mod_reg_bits((1 << clkdm2->dep_bit),
clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP);
}
return 0;
}
/**
* clkdm_read_wkdep - read wakeup dependency state from clkdm2 to clkdm1
* @clkdm1: wake this struct clockdomain * up (dependent)
* @clkdm2: when this struct clockdomain * wakes up (source)
*
* Return 1 if a hardware wakeup dependency exists wherein @clkdm1 will be
* awoken when @clkdm2 wakes up; 0 if dependency is not set; -EINVAL
* if either clockdomain pointer is invalid; or -ENOENT if the hardware
* is incapable.
*
* REVISIT: Currently this function only represents software-controllable
* wakeup dependencies. Wakeup dependencies fixed in hardware are not
* yet handled here.
*/
int clkdm_read_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2)
{
struct clkdm_dep *cd;
if (!clkdm1 || !clkdm2)
return -EINVAL;
cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs);
if (IS_ERR(cd)) {
pr_debug("clockdomain: hardware cannot set/clear wake up of "
"%s when %s wakes up\n", clkdm1->name, clkdm2->name);
return PTR_ERR(cd);
}
/* XXX It's faster to return the atomic wkdep_usecount */
return prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP,
(1 << clkdm2->dep_bit));
}
/**
* clkdm_clear_all_wkdeps - remove all wakeup dependencies from target clkdm
* @clkdm: struct clockdomain * to remove all wakeup dependencies from
*
* Remove all inter-clockdomain wakeup dependencies that could cause
* @clkdm to wake. Intended to be used during boot to initialize the
* PRCM to a known state, after all clockdomains are put into swsup idle
* and woken up. Returns -EINVAL if @clkdm pointer is invalid, or
* 0 upon success.
*/
int clkdm_clear_all_wkdeps(struct clockdomain *clkdm)
{
struct clkdm_dep *cd;
u32 mask = 0;
if (!clkdm)
return -EINVAL;
for (cd = clkdm->wkdep_srcs; cd && cd->clkdm_name; cd++) {
if (!omap_chip_is(cd->omap_chip))
continue;
/* PRM accesses are slow, so minimize them */
mask |= 1 << cd->clkdm->dep_bit;
atomic_set(&cd->wkdep_usecount, 0);
}
prm_clear_mod_reg_bits(mask, clkdm->pwrdm.ptr->prcm_offs, PM_WKDEP);
return 0;
}
/**
* clkdm_add_sleepdep - add a sleep dependency from clkdm2 to clkdm1
* @clkdm1: prevent this struct clockdomain * from sleeping (dependent)
* @clkdm2: when this struct clockdomain * is active (source)
*
* Prevent @clkdm1 from automatically going inactive (and then to
* retention or off) if @clkdm2 is active. Returns -EINVAL if
* presented with invalid clockdomain pointers or called on a machine
* that does not support software-configurable hardware sleep
* dependencies, -ENOENT if the specified dependency cannot be set in
* hardware, or 0 upon success.
*/
int clkdm_add_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2)
{
struct clkdm_dep *cd;
if (!cpu_is_omap34xx())
return -EINVAL;
if (!clkdm1 || !clkdm2)
return -EINVAL;
cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs);
if (IS_ERR(cd)) {
pr_debug("clockdomain: hardware cannot set/clear sleep "
"dependency affecting %s from %s\n", clkdm1->name,
clkdm2->name);
return PTR_ERR(cd);
}
if (atomic_inc_return(&cd->sleepdep_usecount) == 1) {
pr_debug("clockdomain: will prevent %s from sleeping if %s "
"is active\n", clkdm1->name, clkdm2->name);
cm_set_mod_reg_bits((1 << clkdm2->dep_bit),
clkdm1->pwrdm.ptr->prcm_offs,
OMAP3430_CM_SLEEPDEP);
}
return 0;
}
/**
* clkdm_del_sleepdep - remove a sleep dependency from clkdm2 to clkdm1
* @clkdm1: prevent this struct clockdomain * from sleeping (dependent)
* @clkdm2: when this struct clockdomain * is active (source)
*
* Allow @clkdm1 to automatically go inactive (and then to retention or
* off), independent of the activity state of @clkdm2. Returns -EINVAL
* if presented with invalid clockdomain pointers or called on a machine
* that does not support software-configurable hardware sleep dependencies,
* -ENOENT if the specified dependency cannot be cleared in hardware, or
* 0 upon success.
*/
int clkdm_del_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2)
{
struct clkdm_dep *cd;
if (!cpu_is_omap34xx())
return -EINVAL;
if (!clkdm1 || !clkdm2)
return -EINVAL;
cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs);
if (IS_ERR(cd)) {
pr_debug("clockdomain: hardware cannot set/clear sleep "
"dependency affecting %s from %s\n", clkdm1->name,
clkdm2->name);
return PTR_ERR(cd);
}
if (atomic_dec_return(&cd->sleepdep_usecount) == 0) {
pr_debug("clockdomain: will no longer prevent %s from "
"sleeping if %s is active\n", clkdm1->name,
clkdm2->name);
cm_clear_mod_reg_bits((1 << clkdm2->dep_bit),
clkdm1->pwrdm.ptr->prcm_offs,
OMAP3430_CM_SLEEPDEP);
}
return 0;
}
/**
* clkdm_read_sleepdep - read sleep dependency state from clkdm2 to clkdm1
* @clkdm1: prevent this struct clockdomain * from sleeping (dependent)
* @clkdm2: when this struct clockdomain * is active (source)
*
* Return 1 if a hardware sleep dependency exists wherein @clkdm1 will
* not be allowed to automatically go inactive if @clkdm2 is active;
* 0 if @clkdm1's automatic power state inactivity transition is independent
* of @clkdm2's; -EINVAL if either clockdomain pointer is invalid or called
* on a machine that does not support software-configurable hardware sleep
* dependencies; or -ENOENT if the hardware is incapable.
*
* REVISIT: Currently this function only represents software-controllable
* sleep dependencies. Sleep dependencies fixed in hardware are not
* yet handled here.
*/
int clkdm_read_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2)
{
struct clkdm_dep *cd;
if (!cpu_is_omap34xx())
return -EINVAL;
if (!clkdm1 || !clkdm2)
return -EINVAL;
cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs);
if (IS_ERR(cd)) {
pr_debug("clockdomain: hardware cannot set/clear sleep "
"dependency affecting %s from %s\n", clkdm1->name,
clkdm2->name);
return PTR_ERR(cd);
}
/* XXX It's faster to return the atomic sleepdep_usecount */
return prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs,
OMAP3430_CM_SLEEPDEP,
(1 << clkdm2->dep_bit));
}
/**
* clkdm_clear_all_sleepdeps - remove all sleep dependencies from target clkdm
* @clkdm: struct clockdomain * to remove all sleep dependencies from
*
* Remove all inter-clockdomain sleep dependencies that could prevent
* @clkdm from idling. Intended to be used during boot to initialize the
* PRCM to a known state, after all clockdomains are put into swsup idle
* and woken up. Returns -EINVAL if @clkdm pointer is invalid, or
* 0 upon success.
*/
int clkdm_clear_all_sleepdeps(struct clockdomain *clkdm)
{
struct clkdm_dep *cd;
u32 mask = 0;
if (!cpu_is_omap34xx())
return -EINVAL;
if (!clkdm)
return -EINVAL;
for (cd = clkdm->sleepdep_srcs; cd && cd->clkdm_name; cd++) {
if (!omap_chip_is(cd->omap_chip))
continue;
/* PRM accesses are slow, so minimize them */
mask |= 1 << cd->clkdm->dep_bit;
atomic_set(&cd->sleepdep_usecount, 0);
}
prm_clear_mod_reg_bits(mask, clkdm->pwrdm.ptr->prcm_offs,
OMAP3430_CM_SLEEPDEP);
return 0;
}
/**
* omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode
* @clkdm: struct clkdm * of a clockdomain
*
* Return the clockdomain @clkdm current state transition mode from the
* corresponding domain CM_CLKSTCTRL register. Returns -EINVAL if @clkdm
* is NULL or the current mode upon success.
*/
static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm)
{
u32 v;
if (!clkdm)
return -EINVAL;
v = __raw_readl(clkdm->clkstctrl_reg);
v &= clkdm->clktrctrl_mask;
v >>= __ffs(clkdm->clktrctrl_mask);
return v;
}
/**
* omap2_clkdm_sleep - force clockdomain sleep transition
* @clkdm: struct clockdomain *
*
* Instruct the CM to force a sleep transition on the specified
* clockdomain @clkdm. Returns -EINVAL if @clkdm is NULL or if
* clockdomain does not support software-initiated sleep; 0 upon
* success.
*/
int omap2_clkdm_sleep(struct clockdomain *clkdm)
{
if (!clkdm)
return -EINVAL;
if (!(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) {
pr_debug("clockdomain: %s does not support forcing "
"sleep via software\n", clkdm->name);
return -EINVAL;
}
pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name);
if (cpu_is_omap24xx()) {
cm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
clkdm->pwrdm.ptr->prcm_offs, OMAP2_PM_PWSTCTRL);
} else if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
u32 bits = (OMAP34XX_CLKSTCTRL_FORCE_SLEEP <<
__ffs(clkdm->clktrctrl_mask));
u32 v = __raw_readl(clkdm->clkstctrl_reg);
v &= ~(clkdm->clktrctrl_mask);
v |= bits;
__raw_writel(v, clkdm->clkstctrl_reg);
} else {
BUG();
};
return 0;
}
/**
* omap2_clkdm_wakeup - force clockdomain wakeup transition
* @clkdm: struct clockdomain *
*
* Instruct the CM to force a wakeup transition on the specified
* clockdomain @clkdm. Returns -EINVAL if @clkdm is NULL or if the
* clockdomain does not support software-controlled wakeup; 0 upon
* success.
*/
int omap2_clkdm_wakeup(struct clockdomain *clkdm)
{
if (!clkdm)
return -EINVAL;
if (!(clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)) {
pr_debug("clockdomain: %s does not support forcing "
"wakeup via software\n", clkdm->name);
return -EINVAL;
}
pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name);
if (cpu_is_omap24xx()) {
cm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
clkdm->pwrdm.ptr->prcm_offs, OMAP2_PM_PWSTCTRL);
} else if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
u32 bits = (OMAP34XX_CLKSTCTRL_FORCE_WAKEUP <<
__ffs(clkdm->clktrctrl_mask));
u32 v = __raw_readl(clkdm->clkstctrl_reg);
v &= ~(clkdm->clktrctrl_mask);
v |= bits;
__raw_writel(v, clkdm->clkstctrl_reg);
} else {
BUG();
};
return 0;
}
/**
* omap2_clkdm_allow_idle - enable hwsup idle transitions for clkdm
* @clkdm: struct clockdomain *
*
* Allow the hardware to automatically switch the clockdomain @clkdm into
* active or idle states, as needed by downstream clocks. If the
* clockdomain has any downstream clocks enabled in the clock
* framework, wkdep/sleepdep autodependencies are added; this is so
* device drivers can read and write to the device. No return value.
*/
void omap2_clkdm_allow_idle(struct clockdomain *clkdm)
{
if (!clkdm)
return;
if (!(clkdm->flags & CLKDM_CAN_ENABLE_AUTO)) {
pr_debug("clock: automatic idle transitions cannot be enabled "
"on clockdomain %s\n", clkdm->name);
return;
}
pr_debug("clockdomain: enabling automatic idle transitions for %s\n",
clkdm->name);
/*
* XXX This should be removed once TI adds wakeup/sleep
* dependency code and data for OMAP4.
*/
if (cpu_is_omap44xx()) {
WARN_ONCE(1, "clockdomain: OMAP4 wakeup/sleep dependency "
"support is not yet implemented\n");
} else {
if (atomic_read(&clkdm->usecount) > 0)
_clkdm_add_autodeps(clkdm);
}
_omap2_clkdm_set_hwsup(clkdm, 1);
pwrdm_clkdm_state_switch(clkdm);
}
/**
* omap2_clkdm_deny_idle - disable hwsup idle transitions for clkdm
* @clkdm: struct clockdomain *
*
* Prevent the hardware from automatically switching the clockdomain
* @clkdm into inactive or idle states. If the clockdomain has
* downstream clocks enabled in the clock framework, wkdep/sleepdep
* autodependencies are removed. No return value.
*/
void omap2_clkdm_deny_idle(struct clockdomain *clkdm)
{
if (!clkdm)
return;
if (!(clkdm->flags & CLKDM_CAN_DISABLE_AUTO)) {
pr_debug("clockdomain: automatic idle transitions cannot be "
"disabled on %s\n", clkdm->name);
return;
}
pr_debug("clockdomain: disabling automatic idle transitions for %s\n",
clkdm->name);
_omap2_clkdm_set_hwsup(clkdm, 0);
/*
* XXX This should be removed once TI adds wakeup/sleep
* dependency code and data for OMAP4.
*/
if (cpu_is_omap44xx()) {
WARN_ONCE(1, "clockdomain: OMAP4 wakeup/sleep dependency "
"support is not yet implemented\n");
} else {
if (atomic_read(&clkdm->usecount) > 0)
_clkdm_del_autodeps(clkdm);
}
}
/* Clockdomain-to-clock framework interface code */
/**
* omap2_clkdm_clk_enable - add an enabled downstream clock to this clkdm
* @clkdm: struct clockdomain *
* @clk: struct clk * of the enabled downstream clock
*
* Increment the usecount of the clockdomain @clkdm and ensure that it
* is awake before @clk is enabled. Intended to be called by
* clk_enable() code. If the clockdomain is in software-supervised
* idle mode, force the clockdomain to wake. If the clockdomain is in
* hardware-supervised idle mode, add clkdm-pwrdm autodependencies, to
* ensure that devices in the clockdomain can be read from/written to
* by on-chip processors. Returns -EINVAL if passed null pointers;
* returns 0 upon success or if the clockdomain is in hwsup idle mode.
*/
int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk)
{
int v;
/*
* XXX Rewrite this code to maintain a list of enabled
* downstream clocks for debugging purposes?
*/
if (!clkdm || !clk)
return -EINVAL;
if (atomic_inc_return(&clkdm->usecount) > 1)
return 0;
/* Clockdomain now has one enabled downstream clock */
pr_debug("clockdomain: clkdm %s: clk %s now enabled\n", clkdm->name,
clk->name);
if (!clkdm->clkstctrl_reg)
return 0;
v = omap2_clkdm_clktrctrl_read(clkdm);
if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ||
(cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) {
/* Disable HW transitions when we are changing deps */
_omap2_clkdm_set_hwsup(clkdm, 0);
_clkdm_add_autodeps(clkdm);
_omap2_clkdm_set_hwsup(clkdm, 1);
} else {
omap2_clkdm_wakeup(clkdm);
}
pwrdm_wait_transition(clkdm->pwrdm.ptr);
pwrdm_clkdm_state_switch(clkdm);
return 0;
}
/**
* omap2_clkdm_clk_disable - remove an enabled downstream clock from this clkdm
* @clkdm: struct clockdomain *
* @clk: struct clk * of the disabled downstream clock
*
* Decrement the usecount of this clockdomain @clkdm when @clk is
* disabled. Intended to be called by clk_disable() code. If the
* clockdomain usecount goes to 0, put the clockdomain to sleep
* (software-supervised mode) or remove the clkdm autodependencies
* (hardware-supervised mode). Returns -EINVAL if passed null
* pointers; -ERANGE if the @clkdm usecount underflows and debugging
* is enabled; or returns 0 upon success or if the clockdomain is in
* hwsup idle mode.
*/
int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk)
{
int v;
/*
* XXX Rewrite this code to maintain a list of enabled
* downstream clocks for debugging purposes?
*/
if (!clkdm || !clk)
return -EINVAL;
#ifdef DEBUG
if (atomic_read(&clkdm->usecount) == 0) {
WARN_ON(1); /* underflow */
return -ERANGE;
}
#endif
if (atomic_dec_return(&clkdm->usecount) > 0)
return 0;
/* All downstream clocks of this clockdomain are now disabled */
pr_debug("clockdomain: clkdm %s: clk %s now disabled\n", clkdm->name,
clk->name);
if (!clkdm->clkstctrl_reg)
return 0;
v = omap2_clkdm_clktrctrl_read(clkdm);
if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ||
(cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) {
/* Disable HW transitions when we are changing deps */
_omap2_clkdm_set_hwsup(clkdm, 0);
_clkdm_del_autodeps(clkdm);
_omap2_clkdm_set_hwsup(clkdm, 1);
} else {
omap2_clkdm_sleep(clkdm);
}
pwrdm_clkdm_state_switch(clkdm);
return 0;
}