[PATCH v2 2/3] soc: apple: Add driver for Apple PMGR misc controls
Sasha Finkelstein
k at chaosmail.tech
Fri Jul 3 05:44:12 PDT 2026
From: Hector Martin <marcan at marcan.st>
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 <marcan at marcan.st>
Co-developed-by: Sasha Finkelstein <k at chaosmail.tech>
Signed-off-by: Sasha Finkelstein <k at chaosmail.tech>
---
drivers/soc/apple/Kconfig | 10 ++++++++
drivers/soc/apple/Makefile | 2 ++
drivers/soc/apple/apple-pmgr-misc.c | 179 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 191 insertions(+)
diff --git a/drivers/soc/apple/Kconfig b/drivers/soc/apple/Kconfig
index d0ff32182a2b..cad847c90df8 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
+ bool "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..ae8b34f298e8
--- /dev/null
+++ b/drivers/soc/apple/apple-pmgr-misc.c
@@ -0,0 +1,179 @@
+// 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/io.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+
+#define APPLE_CLKGEN_PSTATE 0
+#define APPLE_CLKGEN_PSTATE_DESIRED GENMASK(3, 0)
+
+#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);
+ val &= ~APPLE_CLKGEN_PSTATE_DESIRED;
+ val |= FIELD_PREP(APPLE_CLKGEN_PSTATE_DESIRED, 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 bool 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 false;
+
+ 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 true;
+}
+
+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 = -ENODEV;
+
+ 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;
+
+ if (apple_pmgr_init_device(misc, hw, DEV_FABRIC, "fabric"))
+ ret = 0;
+
+ if (apple_pmgr_init_device(misc, hw, DEV_DCS, "dcs"))
+ ret = 0;
+
+ platform_set_drvdata(pdev, misc);
+
+ return ret;
+}
+
+static const struct apple_pmgr_misc_hw apple_pmgr_misc_hw_t600x = {
+ .dev_min_ps = {
+ [DEV_FABRIC] = SYS_DEV_PSTATE_SUSPEND,
+ [DEV_DCS] = 7,
+ },
+};
+
+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 at marcan.st>");
+MODULE_DESCRIPTION("PMGR misc driver for Apple SoCs");
+MODULE_LICENSE("GPL");
+
+module_platform_driver(apple_pmgr_misc_driver);
--
2.55.0
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