[PATCH v3 2/3] soc: apple: Add driver for Apple PMGR misc controls
From: Sasha Finkelstein <k@chaosmail.tech>
Date: 2026-07-05 08:16:47
Also in:
asahi, linux-devicetree, lkml
Subsystem:
arm/apple machine support, the rest · Maintainers:
Sven Peter, Janne Grunau, Linus Torvalds
From: Hector Martin <redacted> Apple SoCs have PMGR blocks that control a bunch of power-related features. Besides the existing device power state controls (which are very uniform and handled by apple-pmgr-pwrstate), we also need to manage more random registers such as SoC-wide fabric and memory controller power states, which have a different interface. Add a driver for these kitchen sink controls. Right now it implements fabric and memory controller power state switching on system standby/s2idle, which saves about 1W of power or so on t60xx platforms. Signed-off-by: Hector Martin <redacted> Reviewed-by: Sven Peter <sven@kernel.org> Co-developed-by: Sasha Finkelstein <k@chaosmail.tech> Signed-off-by: Sasha Finkelstein <k@chaosmail.tech> --- drivers/soc/apple/Kconfig | 10 ++++++++ drivers/soc/apple/Makefile | 2 ++ drivers/soc/apple/apple-pmgr-misc.c | 181 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 193 insertions(+)
diff --git a/drivers/soc/apple/Kconfig b/drivers/soc/apple/Kconfig
index d0ff32182a2b..db30c0ade948 100644
--- a/drivers/soc/apple/Kconfig
+++ b/drivers/soc/apple/Kconfig@@ -16,6 +16,16 @@ config APPLE_MAILBOX Say Y here if you have an Apple SoC. +config APPLE_PMGR_MISC + tristate "Apple SoC PMGR miscellaneous support" + depends on PM + help + The PMGR block in Apple SoCs provides high-level power state + controls for SoC devices. This driver manages miscellaneous + power controls. + + Say 'y' here if you have a Pro/Max/Ultra Apple SoC. + config APPLE_RTKIT tristate "Apple RTKit co-processor IPC protocol" depends on APPLE_MAILBOX
diff --git a/drivers/soc/apple/Makefile b/drivers/soc/apple/Makefile
index 0b85ab61aefe..0481f7f43b06 100644
--- a/drivers/soc/apple/Makefile
+++ b/drivers/soc/apple/Makefile@@ -3,6 +3,8 @@ obj-$(CONFIG_APPLE_MAILBOX) += apple-mailbox.o apple-mailbox-y = mailbox.o +obj-$(CONFIG_APPLE_PMGR_MISC) += apple-pmgr-misc.o + obj-$(CONFIG_APPLE_RTKIT) += apple-rtkit.o apple-rtkit-y = rtkit.o rtkit-crashlog.o
diff --git a/drivers/soc/apple/apple-pmgr-misc.c b/drivers/soc/apple/apple-pmgr-misc.c
new file mode 100644
index 000000000000..7db29f7de329
--- /dev/null
+++ b/drivers/soc/apple/apple-pmgr-misc.c@@ -0,0 +1,181 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple SoC PMGR device power state driver + * + * Copyright The Asahi Linux Contributors + */ + +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +#define APPLE_CLKGEN_PSTATE 0 +#define APPLE_CLKGEN_PSTATE_DESIRED GENMASK(3, 0) + +#define DCS_DEV_PSTATE_MIN_T600X 7 +#define SYS_DEV_PSTATE_SUSPEND 1 + +enum sys_device { + DEV_FABRIC, + DEV_DCS, + DEV_MAX, +}; + +struct apple_pmgr_sys_device { + void __iomem *base; + u32 active_state; + u32 suspend_state; +}; + +struct apple_pmgr_misc_hw { + u32 dev_min_ps[DEV_MAX]; +}; + +struct apple_pmgr_misc { + struct device *dev; + struct apple_pmgr_sys_device devices[DEV_MAX]; +}; + +static void apple_pmgr_sys_dev_set_pstate(struct apple_pmgr_misc *misc, + enum sys_device dev, bool active) +{ + u32 pstate; + u32 val; + + if (!misc->devices[dev].base) + return; + + if (active) + pstate = misc->devices[dev].active_state; + else + pstate = misc->devices[dev].suspend_state; + + dev_dbg(misc->dev, "set %d ps to pstate %d\n", dev, pstate); + + val = readl_relaxed(misc->devices[dev].base + APPLE_CLKGEN_PSTATE); + FIELD_MODIFY(APPLE_CLKGEN_PSTATE_DESIRED, &val, pstate); + writel_relaxed(val, misc->devices[dev].base + APPLE_CLKGEN_PSTATE); +} + +static int __maybe_unused apple_pmgr_misc_suspend_noirq(struct device *dev) +{ + struct apple_pmgr_misc *misc = dev_get_drvdata(dev); + int i; + + for (i = 0; i < DEV_MAX; i++) + apple_pmgr_sys_dev_set_pstate(misc, i, false); + + return 0; +} + +static int __maybe_unused apple_pmgr_misc_resume_noirq(struct device *dev) +{ + struct apple_pmgr_misc *misc = dev_get_drvdata(dev); + int i; + + for (i = 0; i < DEV_MAX; i++) + apple_pmgr_sys_dev_set_pstate(misc, i, true); + + return 0; +} + +static int apple_pmgr_init_device(struct apple_pmgr_misc *misc, + const struct apple_pmgr_misc_hw *hw, + enum sys_device dev, + const char *device_name) +{ + void __iomem *base; + char name[32]; + u32 val; + + snprintf(name, sizeof(name), "%s-ps", device_name); + + base = devm_platform_ioremap_resource_byname( + to_platform_device(misc->dev), name); + if (IS_ERR(base)) + return PTR_ERR(base); + + val = readl_relaxed(base + APPLE_CLKGEN_PSTATE); + + misc->devices[dev].base = base; + misc->devices[dev].active_state = + FIELD_GET(APPLE_CLKGEN_PSTATE_DESIRED, val); + misc->devices[dev].suspend_state = hw->dev_min_ps[dev]; + + return 0; +} + +static int apple_pmgr_misc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct apple_pmgr_misc_hw *hw; + struct apple_pmgr_misc *misc; + int ret; + + misc = devm_kzalloc(dev, sizeof(*misc), GFP_KERNEL); + if (!misc) + return -ENOMEM; + + misc->dev = dev; + hw = of_device_get_match_data(dev); + if (!hw) + return -EINVAL; + + ret = apple_pmgr_init_device(misc, hw, DEV_FABRIC, "fabric"); + if (ret) + return ret; + + ret = apple_pmgr_init_device(misc, hw, DEV_DCS, "dcs"); + if (ret) + return ret; + + platform_set_drvdata(pdev, misc); + + return 0; +} + +static const struct apple_pmgr_misc_hw apple_pmgr_misc_hw_t600x = { + .dev_min_ps = { + [DEV_FABRIC] = SYS_DEV_PSTATE_SUSPEND, + [DEV_DCS] = DCS_DEV_PSTATE_MIN_T600X, + }, +}; + +static const struct apple_pmgr_misc_hw apple_pmgr_misc_hw_t602x = { + .dev_min_ps = { + [DEV_FABRIC] = SYS_DEV_PSTATE_SUSPEND, + [DEV_DCS] = SYS_DEV_PSTATE_SUSPEND, + }, +}; + +static const struct of_device_id apple_pmgr_misc_of_match[] = { + { .compatible = "apple,t6000-pmgr-misc", .data = &apple_pmgr_misc_hw_t600x }, + { .compatible = "apple,t6020-pmgr-misc", .data = &apple_pmgr_misc_hw_t602x }, + {} +}; + +MODULE_DEVICE_TABLE(of, apple_pmgr_misc_of_match); + +static const struct dev_pm_ops apple_pmgr_misc_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(apple_pmgr_misc_suspend_noirq, + apple_pmgr_misc_resume_noirq) +}; + +static struct platform_driver apple_pmgr_misc_driver = { + .probe = apple_pmgr_misc_probe, + .driver = { + .name = "apple-pmgr-misc", + .of_match_table = apple_pmgr_misc_of_match, + .pm = pm_ptr(&apple_pmgr_misc_pm_ops), + }, +}; + +MODULE_AUTHOR("Hector Martin <marcan@marcan.st>"); +MODULE_DESCRIPTION("PMGR misc driver for Apple SoCs"); +MODULE_LICENSE("GPL"); + +module_platform_driver(apple_pmgr_misc_driver);
--
2.55.0