soc: apple: Add driver for Apple PMGR power state controls
Implements genpd and reset providers for downstream devices. Each instance of the driver binds to a single register and represents a single SoC power domain. The driver does not currently implement all features (clockgate-only state, misc flags), but we declare the respective registers for documentation purposes. These features will be added as they become useful for downstream devices. This also creates the apple/soc tree and Kconfig submenu. Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Hector Martin <marcan@marcan.st>
This commit is contained in:
Hector Martin
Родитель
fa55b7dcdc
Коммит
6df9d38f91
|
|
@ -3,6 +3,7 @@ menu "SOC (System On Chip) specific Drivers"
|
|||
|
||||
source "drivers/soc/actions/Kconfig"
|
||||
source "drivers/soc/amlogic/Kconfig"
|
||||
source "drivers/soc/apple/Kconfig"
|
||||
source "drivers/soc/aspeed/Kconfig"
|
||||
source "drivers/soc/atmel/Kconfig"
|
||||
source "drivers/soc/bcm/Kconfig"
|
||||
|
|
|
|||
|
|
@ -4,6 +4,7 @@
|
|||
#
|
||||
|
||||
obj-$(CONFIG_ARCH_ACTIONS) += actions/
|
||||
obj-$(CONFIG_ARCH_APPLE) += apple/
|
||||
obj-y += aspeed/
|
||||
obj-$(CONFIG_ARCH_AT91) += atmel/
|
||||
obj-y += bcm/
|
||||
|
|
|
|||
|
|
@ -0,0 +1,22 @@
|
|||
# SPDX-License-Identifier: GPL-2.0-only
|
||||
|
||||
if ARCH_APPLE || COMPILE_TEST
|
||||
|
||||
menu "Apple SoC drivers"
|
||||
|
||||
config APPLE_PMGR_PWRSTATE
|
||||
tristate "Apple SoC PMGR power state control"
|
||||
depends on PM
|
||||
select REGMAP
|
||||
select MFD_SYSCON
|
||||
select PM_GENERIC_DOMAINS
|
||||
select RESET_CONTROLLER
|
||||
default ARCH_APPLE
|
||||
help
|
||||
The PMGR block in Apple SoCs provides high-level power state
|
||||
controls for SoC devices. This driver manages them through the
|
||||
generic power domain framework, and also provides reset support.
|
||||
|
||||
endmenu
|
||||
|
||||
endif
|
||||
|
|
@ -0,0 +1,2 @@
|
|||
# SPDX-License-Identifier: GPL-2.0-only
|
||||
obj-$(CONFIG_APPLE_PMGR_PWRSTATE) += apple-pmgr-pwrstate.o
|
||||
|
|
@ -0,0 +1,317 @@
|
|||
// SPDX-License-Identifier: GPL-2.0-only OR MIT
|
||||
/*
|
||||
* Apple SoC PMGR device power state driver
|
||||
*
|
||||
* Copyright The Asahi Linux Contributors
|
||||
*/
|
||||
|
||||
#include <linux/bitops.h>
|
||||
#include <linux/bitfield.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/of.h>
|
||||
#include <linux/of_address.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/pm_domain.h>
|
||||
#include <linux/regmap.h>
|
||||
#include <linux/mfd/syscon.h>
|
||||
#include <linux/reset-controller.h>
|
||||
#include <linux/module.h>
|
||||
|
||||
#define APPLE_PMGR_RESET BIT(31)
|
||||
#define APPLE_PMGR_AUTO_ENABLE BIT(28)
|
||||
#define APPLE_PMGR_PS_AUTO GENMASK(27, 24)
|
||||
#define APPLE_PMGR_PARENT_OFF BIT(11)
|
||||
#define APPLE_PMGR_DEV_DISABLE BIT(10)
|
||||
#define APPLE_PMGR_WAS_CLKGATED BIT(9)
|
||||
#define APPLE_PMGR_WAS_PWRGATED BIT(8)
|
||||
#define APPLE_PMGR_PS_ACTUAL GENMASK(7, 4)
|
||||
#define APPLE_PMGR_PS_TARGET GENMASK(3, 0)
|
||||
|
||||
#define APPLE_PMGR_FLAGS (APPLE_PMGR_WAS_CLKGATED | APPLE_PMGR_WAS_PWRGATED)
|
||||
|
||||
#define APPLE_PMGR_PS_ACTIVE 0xf
|
||||
#define APPLE_PMGR_PS_CLKGATE 0x4
|
||||
#define APPLE_PMGR_PS_PWRGATE 0x0
|
||||
|
||||
#define APPLE_PMGR_PS_SET_TIMEOUT 100
|
||||
#define APPLE_PMGR_RESET_TIME 1
|
||||
|
||||
struct apple_pmgr_ps {
|
||||
struct device *dev;
|
||||
struct generic_pm_domain genpd;
|
||||
struct reset_controller_dev rcdev;
|
||||
struct regmap *regmap;
|
||||
u32 offset;
|
||||
};
|
||||
|
||||
#define genpd_to_apple_pmgr_ps(_genpd) container_of(_genpd, struct apple_pmgr_ps, genpd)
|
||||
#define rcdev_to_apple_pmgr_ps(_rcdev) container_of(_rcdev, struct apple_pmgr_ps, rcdev)
|
||||
|
||||
static int apple_pmgr_ps_set(struct generic_pm_domain *genpd, u32 pstate, bool auto_enable)
|
||||
{
|
||||
int ret;
|
||||
struct apple_pmgr_ps *ps = genpd_to_apple_pmgr_ps(genpd);
|
||||
u32 reg;
|
||||
|
||||
ret = regmap_read(ps->regmap, ps->offset, ®);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
/* Resets are synchronous, and only work if the device is powered and clocked. */
|
||||
if (reg & APPLE_PMGR_RESET && pstate != APPLE_PMGR_PS_ACTIVE)
|
||||
dev_err(ps->dev, "PS %s: powering off with RESET active\n",
|
||||
genpd->name);
|
||||
|
||||
reg &= ~(APPLE_PMGR_AUTO_ENABLE | APPLE_PMGR_FLAGS | APPLE_PMGR_PS_TARGET);
|
||||
reg |= FIELD_PREP(APPLE_PMGR_PS_TARGET, pstate);
|
||||
|
||||
dev_dbg(ps->dev, "PS %s: pwrstate = 0x%x: 0x%x\n", genpd->name, pstate, reg);
|
||||
|
||||
regmap_write(ps->regmap, ps->offset, reg);
|
||||
|
||||
ret = regmap_read_poll_timeout_atomic(
|
||||
ps->regmap, ps->offset, reg,
|
||||
(FIELD_GET(APPLE_PMGR_PS_ACTUAL, reg) == pstate), 1,
|
||||
APPLE_PMGR_PS_SET_TIMEOUT);
|
||||
if (ret < 0)
|
||||
dev_err(ps->dev, "PS %s: Failed to reach power state 0x%x (now: 0x%x)\n",
|
||||
genpd->name, pstate, reg);
|
||||
|
||||
if (auto_enable) {
|
||||
/* Not all devices implement this; this is a no-op where not implemented. */
|
||||
reg &= ~APPLE_PMGR_FLAGS;
|
||||
reg |= APPLE_PMGR_AUTO_ENABLE;
|
||||
regmap_write(ps->regmap, ps->offset, reg);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static bool apple_pmgr_ps_is_active(struct apple_pmgr_ps *ps)
|
||||
{
|
||||
u32 reg = 0;
|
||||
|
||||
regmap_read(ps->regmap, ps->offset, ®);
|
||||
/*
|
||||
* We consider domains as active if they are actually on, or if they have auto-PM
|
||||
* enabled and the intended target is on.
|
||||
*/
|
||||
return (FIELD_GET(APPLE_PMGR_PS_ACTUAL, reg) == APPLE_PMGR_PS_ACTIVE ||
|
||||
(FIELD_GET(APPLE_PMGR_PS_TARGET, reg) == APPLE_PMGR_PS_ACTIVE &&
|
||||
reg & APPLE_PMGR_AUTO_ENABLE));
|
||||
}
|
||||
|
||||
static int apple_pmgr_ps_power_on(struct generic_pm_domain *genpd)
|
||||
{
|
||||
return apple_pmgr_ps_set(genpd, APPLE_PMGR_PS_ACTIVE, true);
|
||||
}
|
||||
|
||||
static int apple_pmgr_ps_power_off(struct generic_pm_domain *genpd)
|
||||
{
|
||||
return apple_pmgr_ps_set(genpd, APPLE_PMGR_PS_PWRGATE, false);
|
||||
}
|
||||
|
||||
static int apple_pmgr_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
|
||||
{
|
||||
struct apple_pmgr_ps *ps = rcdev_to_apple_pmgr_ps(rcdev);
|
||||
|
||||
mutex_lock(&ps->genpd.mlock);
|
||||
|
||||
if (ps->genpd.status == GENPD_STATE_OFF)
|
||||
dev_err(ps->dev, "PS 0x%x: asserting RESET while powered down\n", ps->offset);
|
||||
|
||||
dev_dbg(ps->dev, "PS 0x%x: assert reset\n", ps->offset);
|
||||
/* Quiesce device before asserting reset */
|
||||
regmap_update_bits(ps->regmap, ps->offset, APPLE_PMGR_FLAGS | APPLE_PMGR_DEV_DISABLE,
|
||||
APPLE_PMGR_DEV_DISABLE);
|
||||
regmap_update_bits(ps->regmap, ps->offset, APPLE_PMGR_FLAGS | APPLE_PMGR_RESET,
|
||||
APPLE_PMGR_RESET);
|
||||
|
||||
mutex_unlock(&ps->genpd.mlock);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int apple_pmgr_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
|
||||
{
|
||||
struct apple_pmgr_ps *ps = rcdev_to_apple_pmgr_ps(rcdev);
|
||||
|
||||
mutex_lock(&ps->genpd.mlock);
|
||||
|
||||
dev_dbg(ps->dev, "PS 0x%x: deassert reset\n", ps->offset);
|
||||
regmap_update_bits(ps->regmap, ps->offset, APPLE_PMGR_FLAGS | APPLE_PMGR_RESET, 0);
|
||||
regmap_update_bits(ps->regmap, ps->offset, APPLE_PMGR_FLAGS | APPLE_PMGR_DEV_DISABLE, 0);
|
||||
|
||||
if (ps->genpd.status == GENPD_STATE_OFF)
|
||||
dev_err(ps->dev, "PS 0x%x: RESET was deasserted while powered down\n", ps->offset);
|
||||
|
||||
mutex_unlock(&ps->genpd.mlock);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int apple_pmgr_reset_reset(struct reset_controller_dev *rcdev, unsigned long id)
|
||||
{
|
||||
int ret;
|
||||
|
||||
ret = apple_pmgr_reset_assert(rcdev, id);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
usleep_range(APPLE_PMGR_RESET_TIME, 2 * APPLE_PMGR_RESET_TIME);
|
||||
|
||||
return apple_pmgr_reset_deassert(rcdev, id);
|
||||
}
|
||||
|
||||
static int apple_pmgr_reset_status(struct reset_controller_dev *rcdev, unsigned long id)
|
||||
{
|
||||
struct apple_pmgr_ps *ps = rcdev_to_apple_pmgr_ps(rcdev);
|
||||
u32 reg = 0;
|
||||
|
||||
regmap_read(ps->regmap, ps->offset, ®);
|
||||
|
||||
return !!(reg & APPLE_PMGR_RESET);
|
||||
}
|
||||
|
||||
const struct reset_control_ops apple_pmgr_reset_ops = {
|
||||
.assert = apple_pmgr_reset_assert,
|
||||
.deassert = apple_pmgr_reset_deassert,
|
||||
.reset = apple_pmgr_reset_reset,
|
||||
.status = apple_pmgr_reset_status,
|
||||
};
|
||||
|
||||
static int apple_pmgr_reset_xlate(struct reset_controller_dev *rcdev,
|
||||
const struct of_phandle_args *reset_spec)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int apple_pmgr_ps_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct device *dev = &pdev->dev;
|
||||
struct device_node *node = dev->of_node;
|
||||
struct apple_pmgr_ps *ps;
|
||||
struct regmap *regmap;
|
||||
struct of_phandle_iterator it;
|
||||
int ret;
|
||||
const char *name;
|
||||
bool active;
|
||||
|
||||
regmap = syscon_node_to_regmap(node->parent);
|
||||
if (IS_ERR(regmap))
|
||||
return PTR_ERR(regmap);
|
||||
|
||||
ps = devm_kzalloc(dev, sizeof(*ps), GFP_KERNEL);
|
||||
if (!ps)
|
||||
return -ENOMEM;
|
||||
|
||||
ps->dev = dev;
|
||||
ps->regmap = regmap;
|
||||
|
||||
ret = of_property_read_string(node, "label", &name);
|
||||
if (ret < 0) {
|
||||
dev_err(dev, "missing label property\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = of_property_read_u32(node, "reg", &ps->offset);
|
||||
if (ret < 0) {
|
||||
dev_err(dev, "missing reg property\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
ps->genpd.name = name;
|
||||
ps->genpd.power_on = apple_pmgr_ps_power_on;
|
||||
ps->genpd.power_off = apple_pmgr_ps_power_off;
|
||||
|
||||
active = apple_pmgr_ps_is_active(ps);
|
||||
if (of_property_read_bool(node, "apple,always-on")) {
|
||||
ps->genpd.flags |= GENPD_FLAG_ALWAYS_ON;
|
||||
if (!active) {
|
||||
dev_warn(dev, "always-on domain %s is not on at boot\n", name);
|
||||
/* Turn it on so pm_genpd_init does not fail */
|
||||
active = apple_pmgr_ps_power_on(&ps->genpd) == 0;
|
||||
}
|
||||
}
|
||||
|
||||
/* Turn on auto-PM if the domain is already on */
|
||||
if (active)
|
||||
regmap_update_bits(regmap, ps->offset, APPLE_PMGR_FLAGS | APPLE_PMGR_AUTO_ENABLE,
|
||||
APPLE_PMGR_AUTO_ENABLE);
|
||||
|
||||
ret = pm_genpd_init(&ps->genpd, NULL, !active);
|
||||
if (ret < 0) {
|
||||
dev_err(dev, "pm_genpd_init failed\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = of_genpd_add_provider_simple(node, &ps->genpd);
|
||||
if (ret < 0) {
|
||||
dev_err(dev, "of_genpd_add_provider_simple failed\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
of_for_each_phandle(&it, ret, node, "power-domains", "#power-domain-cells", -1) {
|
||||
struct of_phandle_args parent, child;
|
||||
|
||||
parent.np = it.node;
|
||||
parent.args_count = of_phandle_iterator_args(&it, parent.args, MAX_PHANDLE_ARGS);
|
||||
child.np = node;
|
||||
child.args_count = 0;
|
||||
ret = of_genpd_add_subdomain(&parent, &child);
|
||||
|
||||
if (ret == -EPROBE_DEFER) {
|
||||
of_node_put(parent.np);
|
||||
goto err_remove;
|
||||
} else if (ret < 0) {
|
||||
dev_err(dev, "failed to add to parent domain: %d (%s -> %s)\n",
|
||||
ret, it.node->name, node->name);
|
||||
of_node_put(parent.np);
|
||||
goto err_remove;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Do not participate in regular PM; parent power domains are handled via the
|
||||
* genpd hierarchy.
|
||||
*/
|
||||
pm_genpd_remove_device(dev);
|
||||
|
||||
ps->rcdev.owner = THIS_MODULE;
|
||||
ps->rcdev.nr_resets = 1;
|
||||
ps->rcdev.ops = &apple_pmgr_reset_ops;
|
||||
ps->rcdev.of_node = dev->of_node;
|
||||
ps->rcdev.of_reset_n_cells = 0;
|
||||
ps->rcdev.of_xlate = apple_pmgr_reset_xlate;
|
||||
|
||||
ret = devm_reset_controller_register(dev, &ps->rcdev);
|
||||
if (ret < 0)
|
||||
goto err_remove;
|
||||
|
||||
return 0;
|
||||
err_remove:
|
||||
of_genpd_del_provider(node);
|
||||
pm_genpd_remove(&ps->genpd);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static const struct of_device_id apple_pmgr_ps_of_match[] = {
|
||||
{ .compatible = "apple,pmgr-pwrstate" },
|
||||
{}
|
||||
};
|
||||
|
||||
MODULE_DEVICE_TABLE(of, apple_pmgr_ps_of_match);
|
||||
|
||||
static struct platform_driver apple_pmgr_ps_driver = {
|
||||
.probe = apple_pmgr_ps_probe,
|
||||
.driver = {
|
||||
.name = "apple-pmgr-pwrstate",
|
||||
.of_match_table = apple_pmgr_ps_of_match,
|
||||
},
|
||||
};
|
||||
|
||||
MODULE_AUTHOR("Hector Martin <marcan@marcan.st>");
|
||||
MODULE_DESCRIPTION("PMGR power state driver for Apple SoCs");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
|
||||
module_platform_driver(apple_pmgr_ps_driver);
|
||||
Загрузка…
Ссылка в новой задаче