[PATCH v3 1/3] dt-bindings: power: Add SiFive Domain Management controllers

[PATCH v3 1/3] dt-bindings: power: Add SiFive Domain Management controllers

[Nick Hu]

SiFive Domain Management controller includes the following components
- SiFive Tile Management Controller
- SiFive Cluster Management Controller
- SiFive Core Complex Management Controller

These controllers control the clock and power domain of the
corresponding domain.

Add `- {}` for the first entry [1][2]. Once the SoCs are ready, we will
add the SoC compatible string at that time.

Links:
- [1] https://lore.kernel.org/lkml/20250311195953.GA14239-robh@kernel.org/
- [2] https://lore.kernel.org/lkml/CAKddAkAzDGL-7MbroRqQnZzPXOquUMKNuGGppqB-d_XZXbcvBA@mail.gmail.com/T/#t

Signed-off-by: Nick Hu <nick.hu@sifive.com>
Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
---
 .../devicetree/bindings/power/sifive,tmc.yaml | 58 +++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/sifive,tmc.yaml

diff --git a/Documentation/devicetree/bindings/power/sifive,tmc.yaml b/Documentation/devicetree/bindings/power/sifive,tmc.yaml
new file mode 100644
index 000000000000..4ab2b94785f4
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/sifive,tmc.yaml
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/power/sifive,tmc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive Domain Management Controller
+
+maintainers:
+  - Cyan Yang <cyan.yang@sifive.com>
+  - Nick Hu <nick.hu@sifive.com>
+  - Samuel Holland <samuel.holland@sifive.com>
+
+description: |
+  SiFive Domain Management Controllers includes the following components
+    - Tile Management Controller (TMC)
+    - Cluster Management Controller (CMC)
+    - Subsystem Management Controller (SMC)
+  These controllers manage both the clock and power domains of the
+  associated components. They support the SiFive Quiet Interface Protocol
+  (SQIP) starting from Version 1. The control method differs from Version
+  0, making them incompatible.
+
+allOf:
+  - $ref: power-domain.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - {} # Leave a empty for future SoC specific compatible string
+          - const: sifive,cmc2
+      - items:
+          - {} # Leave a empty for future SoC specific compatible string
+          - const: sifive,smc0
+      - items:
+          - {} # Leave a empty for future SoC specific compatible string
+          - const: sifive,smc1
+      - items:
+          - {} # Leave a empty for future SoC specific compatible string
+          - const: sifive,tmc0
+      - items:
+          - {} # Leave a empty for future SoC specific compatible string
+          - const: sifive,tmc1
+
+  reg:
+    maxItems: 1
+
+  "#power-domain-cells":
+    const: 0
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+# The example will be added once the SoCs are ready
-- 
2.17.1

Re: [PATCH v3 1/3] dt-bindings: power: Add SiFive Domain Management controllers

[Rob Herring (Arm)]

On Wed, 02 Jul 2025 17:12:34 +0800, Nick Hu wrote:
> SiFive Domain Management controller includes the following components
> - SiFive Tile Management Controller
> - SiFive Cluster Management Controller
> - SiFive Core Complex Management Controller
> 
> These controllers control the clock and power domain of the
> corresponding domain.
> 
> Add `- {}` for the first entry [1][2]. Once the SoCs are ready, we will
> add the SoC compatible string at that time.
> 
> Links:
> - [1] https://lore.kernel.org/lkml/20250311195953.GA14239-robh@kernel.org/
> - [2] https://lore.kernel.org/lkml/CAKddAkAzDGL-7MbroRqQnZzPXOquUMKNuGGppqB-d_XZXbcvBA@mail.gmail.com/T/#t
> 
> Signed-off-by: Nick Hu <nick.hu@sifive.com>
> Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
> ---
>  .../devicetree/bindings/power/sifive,tmc.yaml | 58 +++++++++++++++++++
>  1 file changed, 58 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/power/sifive,tmc.yaml
> 

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>

[PATCH v3 2/3] cpuidle: riscv-sbi: Work with the external pmdomain driver

[Nick Hu]

To work with the external pmdomain driver, exposing the
`sbi_cpuidle_pd_power_off` and `sbi_dt_parse_state_node` so the external
pmdomain driver can parse the riscv idle state data and set the domain
idle state where powering off. In addition, separate the genpd init and
the idle driver init. The genpd remains functional even when the idle
state is absent.

Co-developed-by: Samuel Holland <samuel.holland@sifive.com>
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Signed-off-by: Nick Hu <nick.hu@sifive.com>
---
 drivers/cpuidle/cpuidle-riscv-sbi.c | 46 ++++++++++++++++++-----------
 drivers/cpuidle/cpuidle-riscv-sbi.h | 20 +++++++++++++
 2 files changed, 48 insertions(+), 18 deletions(-)
 create mode 100644 drivers/cpuidle/cpuidle-riscv-sbi.h

diff --git a/drivers/cpuidle/cpuidle-riscv-sbi.c b/drivers/cpuidle/cpuidle-riscv-sbi.c
index 0fe1ece9fbdc..be3949971eed 100644
--- a/drivers/cpuidle/cpuidle-riscv-sbi.c
+++ b/drivers/cpuidle/cpuidle-riscv-sbi.c
@@ -27,6 +27,7 @@
 #include <asm/suspend.h>
 
 #include "cpuidle.h"
+#include "cpuidle-riscv-sbi.h"
 #include "dt_idle_states.h"
 #include "dt_idle_genpd.h"
 
@@ -43,7 +44,6 @@ struct sbi_domain_state {
 static DEFINE_PER_CPU_READ_MOSTLY(struct sbi_cpuidle_data, sbi_cpuidle_data);
 static DEFINE_PER_CPU(struct sbi_domain_state, domain_state);
 static bool sbi_cpuidle_use_osi;
-static bool sbi_cpuidle_use_cpuhp;
 static bool sbi_cpuidle_pd_allow_domain_state;
 
 static inline void sbi_set_domain_state(u32 state)
@@ -171,9 +171,6 @@ static void sbi_idle_init_cpuhp(void)
 {
 	int err;
 
-	if (!sbi_cpuidle_use_cpuhp)
-		return;
-
 	err = cpuhp_setup_state_nocalls(CPUHP_AP_CPU_PM_STARTING,
 					"cpuidle/sbi:online",
 					sbi_cpuidle_cpuhp_up,
@@ -188,7 +185,7 @@ static const struct of_device_id sbi_cpuidle_state_match[] = {
 	{ },
 };
 
-static int sbi_dt_parse_state_node(struct device_node *np, u32 *state)
+int sbi_dt_parse_state_node(struct device_node *np, u32 *state)
 {
 	int err = of_property_read_u32(np, "riscv,sbi-suspend-param", state);
 
@@ -213,10 +210,6 @@ static int sbi_dt_cpu_init_topology(struct cpuidle_driver *drv,
 	if (!sbi_cpuidle_use_osi)
 		return 0;
 
-	data->dev = dt_idle_attach_cpu(cpu, "sbi");
-	if (IS_ERR_OR_NULL(data->dev))
-		return PTR_ERR_OR_ZERO(data->dev);
-
 	/*
 	 * Using the deepest state for the CPU to trigger a potential selection
 	 * of a shared state for the domain, assumes the domain states are all
@@ -226,7 +219,6 @@ static int sbi_dt_cpu_init_topology(struct cpuidle_driver *drv,
 	drv->states[state_count - 1].enter = sbi_enter_domain_idle_state;
 	drv->states[state_count - 1].enter_s2idle =
 					sbi_enter_s2idle_domain_idle_state;
-	sbi_cpuidle_use_cpuhp = true;
 
 	return 0;
 }
@@ -282,7 +274,6 @@ static void sbi_cpuidle_deinit_cpu(int cpu)
 	struct sbi_cpuidle_data *data = per_cpu_ptr(&sbi_cpuidle_data, cpu);
 
 	dt_idle_detach_cpu(data->dev);
-	sbi_cpuidle_use_cpuhp = false;
 }
 
 static int sbi_cpuidle_init_cpu(struct device *dev, int cpu)
@@ -325,8 +316,9 @@ static int sbi_cpuidle_init_cpu(struct device *dev, int cpu)
 	/* Initialize idle states from DT. */
 	ret = sbi_cpuidle_dt_init_states(dev, drv, cpu, state_count);
 	if (ret) {
-		pr_err("HART%ld: failed to init idle states\n",
-		       cpuid_to_hartid_map(cpu));
+		if (ret != -EPROBE_DEFER)
+			pr_err("HART%ld: failed to init idle states\n",
+			       cpuid_to_hartid_map(cpu));
 		return ret;
 	}
 
@@ -356,7 +348,7 @@ static void sbi_cpuidle_domain_sync_state(struct device *dev)
 
 #ifdef CONFIG_DT_IDLE_GENPD
 
-static int sbi_cpuidle_pd_power_off(struct generic_pm_domain *pd)
+int sbi_cpuidle_pd_power_off(struct generic_pm_domain *pd)
 {
 	struct genpd_power_state *state = &pd->states[pd->state_idx];
 	u32 *pd_state;
@@ -529,6 +521,27 @@ static int sbi_cpuidle_probe(struct platform_device *pdev)
 			return ret;
 	}
 
+	/* Attaching the cpu to the corresponding power domain */
+	if (sbi_cpuidle_use_osi) {
+		for_each_present_cpu(cpu) {
+			struct sbi_cpuidle_data *data = per_cpu_ptr(&sbi_cpuidle_data, cpu);
+
+			data->dev = dt_idle_attach_cpu(cpu, "sbi");
+			if (IS_ERR_OR_NULL(data->dev)) {
+				ret = PTR_ERR_OR_ZERO(data->dev);
+				if (ret != -EPROBE_DEFER)
+					pr_debug("Hart%ld: fail to attach the power domain\n",
+						 cpuid_to_hartid_map(cpu));
+
+				while (--cpu >= 0)
+					dt_idle_detach_cpu(data->dev);
+				return ret;
+			}
+		}
+		/* Setup CPU hotplut notifiers */
+		sbi_idle_init_cpuhp();
+	}
+
 	/* Initialize CPU idle driver for each present CPU */
 	for_each_present_cpu(cpu) {
 		ret = sbi_cpuidle_init_cpu(&pdev->dev, cpu);
@@ -539,9 +552,6 @@ static int sbi_cpuidle_probe(struct platform_device *pdev)
 		}
 	}
 
-	/* Setup CPU hotplut notifiers */
-	sbi_idle_init_cpuhp();
-
 	if (cpuidle_disabled())
 		pr_info("cpuidle is disabled\n");
 	else
@@ -556,7 +566,7 @@ static int sbi_cpuidle_probe(struct platform_device *pdev)
 		cpuidle_unregister(drv);
 		sbi_cpuidle_deinit_cpu(cpu);
 	}
-
+out:
 	return ret;
 }
 
diff --git a/drivers/cpuidle/cpuidle-riscv-sbi.h b/drivers/cpuidle/cpuidle-riscv-sbi.h
new file mode 100644
index 000000000000..f39186b65a10
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-riscv-sbi.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __CPUIDLE_RISCV_SBI
+#define __CPUIDLE_RISCV_SBI
+
+#ifdef CONFIG_DT_IDLE_GENPD
+
+int sbi_cpuidle_pd_power_off(struct generic_pm_domain *pd);
+
+#else
+
+static inline int sbi_cpuidle_pd_power_off(struct generic_pm_domain *pd)
+{
+	return 0;
+}
+
+#endif
+
+int sbi_dt_parse_state_node(struct device_node *np, u32 *state);
+
+#endif
-- 
2.17.1

Re: [PATCH v3 2/3] cpuidle: riscv-sbi: Work with the external pmdomain driver

[kernel test robot]

Hi Nick,

kernel test robot noticed the following build warnings:

[auto build test WARNING on rafael-pm/linux-next]
[also build test WARNING on rafael-pm/bleeding-edge robh/for-next linus/master v6.16-rc4 next-20250703]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Nick-Hu/cpuidle-riscv-sbi-Work-with-the-external-pmdomain-driver/20250702-181250
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
patch link:    https://lore.kernel.org/r/20250702091236.5281-3-nick.hu%40sifive.com
patch subject: [PATCH v3 2/3] cpuidle: riscv-sbi: Work with the external pmdomain driver
config: riscv-randconfig-001-20250703 (https://download.01.org/0day-ci/archive/20250704/202507040001.Jm6FQyH6-lkp@intel.com/config)
compiler: riscv64-linux-gcc (GCC) 13.4.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250704/202507040001.Jm6FQyH6-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507040001.Jm6FQyH6-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/cpuidle/cpuidle-riscv-sbi.c: In function 'sbi_cpuidle_probe':
>> drivers/cpuidle/cpuidle-riscv-sbi.c:569:1: warning: label 'out' defined but not used [-Wunused-label]
     569 | out:
         | ^~~


vim +/out +569 drivers/cpuidle/cpuidle-riscv-sbi.c

   493	
   494	static int sbi_cpuidle_probe(struct platform_device *pdev)
   495	{
   496		int cpu, ret;
   497		struct cpuidle_driver *drv;
   498		struct cpuidle_device *dev;
   499		struct device_node *pds_node;
   500	
   501		/* Detect OSI support based on CPU DT nodes */
   502		sbi_cpuidle_use_osi = true;
   503		for_each_possible_cpu(cpu) {
   504			struct device_node *np __free(device_node) = of_cpu_device_node_get(cpu);
   505			if (np &&
   506			    of_property_present(np, "power-domains") &&
   507			    of_property_present(np, "power-domain-names")) {
   508				continue;
   509			} else {
   510				sbi_cpuidle_use_osi = false;
   511				break;
   512			}
   513		}
   514	
   515		/* Populate generic power domains from DT nodes */
   516		pds_node = of_find_node_by_path("/cpus/power-domains");
   517		if (pds_node) {
   518			ret = sbi_genpd_probe(pds_node);
   519			of_node_put(pds_node);
   520			if (ret)
   521				return ret;
   522		}
   523	
   524		/* Attaching the cpu to the corresponding power domain */
   525		if (sbi_cpuidle_use_osi) {
   526			for_each_present_cpu(cpu) {
   527				struct sbi_cpuidle_data *data = per_cpu_ptr(&sbi_cpuidle_data, cpu);
   528	
   529				data->dev = dt_idle_attach_cpu(cpu, "sbi");
   530				if (IS_ERR_OR_NULL(data->dev)) {
   531					ret = PTR_ERR_OR_ZERO(data->dev);
   532					if (ret != -EPROBE_DEFER)
   533						pr_debug("Hart%ld: fail to attach the power domain\n",
   534							 cpuid_to_hartid_map(cpu));
   535	
   536					while (--cpu >= 0)
   537						dt_idle_detach_cpu(data->dev);
   538					return ret;
   539				}
   540			}
   541			/* Setup CPU hotplut notifiers */
   542			sbi_idle_init_cpuhp();
   543		}
   544	
   545		/* Initialize CPU idle driver for each present CPU */
   546		for_each_present_cpu(cpu) {
   547			ret = sbi_cpuidle_init_cpu(&pdev->dev, cpu);
   548			if (ret) {
   549				pr_debug("HART%ld: idle driver init failed\n",
   550					 cpuid_to_hartid_map(cpu));
   551				goto out_fail;
   552			}
   553		}
   554	
   555		if (cpuidle_disabled())
   556			pr_info("cpuidle is disabled\n");
   557		else
   558			pr_info("idle driver registered for all CPUs\n");
   559	
   560		return 0;
   561	
   562	out_fail:
   563		while (--cpu >= 0) {
   564			dev = per_cpu(cpuidle_devices, cpu);
   565			drv = cpuidle_get_cpu_driver(dev);
   566			cpuidle_unregister(drv);
   567			sbi_cpuidle_deinit_cpu(cpu);
   568		}
 > 569	out:
   570		return ret;
   571	}
   572	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

[PATCH v3 3/3] cpuidle: Add SiFive power provider

[Nick Hu]

The SiFive DMC is the power provider of the devices that inside the
SiFive CPU power domains, which include Tile, Cluster and Core Complex
power domains. Before the cpu entering the firmware-based idle state,
each devices that inside the corresponding domain should be suspended
properly. So this driver will create the power provider and set the
correct idle state.

Signed-off-by: Nick Hu <nick.hu@sifive.com>
---
 drivers/cpuidle/Kconfig.riscv           |  12 +++
 drivers/cpuidle/Makefile                |   1 +
 drivers/cpuidle/cpuidle-sifive-dmc-pd.c | 102 ++++++++++++++++++++++++
 3 files changed, 115 insertions(+)
 create mode 100644 drivers/cpuidle/cpuidle-sifive-dmc-pd.c

diff --git a/drivers/cpuidle/Kconfig.riscv b/drivers/cpuidle/Kconfig.riscv
index 78518c26af74..f461d09e0bdc 100644
--- a/drivers/cpuidle/Kconfig.riscv
+++ b/drivers/cpuidle/Kconfig.riscv
@@ -13,3 +13,15 @@ config RISCV_SBI_CPUIDLE
 	  Select this option to enable RISC-V SBI firmware based CPU idle
 	  driver for RISC-V systems. This drivers also supports hierarchical
 	  DT based layout of the idle state.
+
+config SIFIVE_DMC_PD_CPUIDLE
+	bool "SiFive DMC SBI PD Provider Driver"
+	depends on ARCH_SIFIVE && RISCV_SBI && PM && OF
+	select PM_GENERIC_DOMAINS
+	select PM_GENERIC_DOMAINS_OF
+	select RISCV_SBI_CPUIDLE
+	default y
+	help
+	  Select this option to enable SiFive DMC SBI PD Provider driver.
+	  This driver will create the genpd provider and work with the
+	  RISC-V SBI firmware based CPU idle driver.
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index 1de9e92c5b0f..1f8e01b415e8 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -42,3 +42,4 @@ obj-$(CONFIG_POWERNV_CPUIDLE)		+= cpuidle-powernv.o
 ###############################################################################
 # RISC-V drivers
 obj-$(CONFIG_RISCV_SBI_CPUIDLE)		+= cpuidle-riscv-sbi.o
+obj-$(CONFIG_SIFIVE_DMC_PD_CPUIDLE)	+= cpuidle-sifive-dmc-pd.o
diff --git a/drivers/cpuidle/cpuidle-sifive-dmc-pd.c b/drivers/cpuidle/cpuidle-sifive-dmc-pd.c
new file mode 100644
index 000000000000..1c6b2131e573
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-sifive-dmc-pd.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SiFive CPUIDLE SBI PD driver
+ */
+
+#define pr_fmt(fmt) "sifive_cpuidle_sbi_pd: " fmt
+
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+
+#include "cpuidle-riscv-sbi.h"
+#include "dt_idle_genpd.h"
+
+static void sifive_dmc_remove(struct platform_device *pdev)
+{
+	struct generic_pm_domain *pd = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+
+	pm_runtime_disable(dev);
+	of_genpd_del_provider(dev->of_node);
+	pm_genpd_remove(pd);
+	dt_idle_pd_free(pd);
+}
+
+static int sifive_dmc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct generic_pm_domain *pd;
+	struct of_phandle_args child, parent;
+	int ret = -ENOMEM;
+
+	pd = dt_idle_pd_alloc(np, sbi_dt_parse_state_node);
+	if (!pd)
+		goto fail;
+
+	pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN;
+	pd->power_off = sbi_cpuidle_pd_power_off;
+
+	ret = pm_genpd_init(pd, &pm_domain_cpu_gov, false);
+	if (ret)
+		goto free_pd;
+
+	ret = of_genpd_add_provider_simple(np, pd);
+	if (ret)
+		goto remove_pd;
+
+	if (of_parse_phandle_with_args(np, "power-domains",
+				       "#power-domain-cells", 0,
+				       &parent) == 0) {
+		child.np = np;
+		child.args_count = 0;
+
+		if (of_genpd_add_subdomain(&parent, &child))
+			pr_warn("%pOF failed to add subdomain: %pOF\n",
+				parent.np, child.np);
+		else
+			pr_debug("%pOF has a child subdomain: %pOF.\n",
+				 parent.np, child.np);
+	}
+
+	platform_set_drvdata(pdev, pd);
+	pm_runtime_enable(dev);
+	pr_info("%s create success\n", pd->name);
+	return 0;
+
+remove_pd:
+	pm_genpd_remove(pd);
+free_pd:
+	dt_idle_pd_free(pd);
+fail:
+	pr_info("%s create fail\n", pd->name);
+
+	return ret;
+}
+
+static const struct of_device_id sifive_dmc_of_match[] = {
+	{ .compatible = "sifive,tmc1", },
+	{ .compatible = "sifive,tmc0", },
+	{ .compatible = "sifive,smc1", },
+	{ .compatible = "sifive,smc0", },
+	{ .compatible = "sifive,cmc2", },
+	{}
+};
+
+static struct platform_driver sifive_dmc_driver = {
+	.probe = sifive_dmc_probe,
+	.remove = sifive_dmc_remove,
+	.driver = {
+		.name = "sifive_dmc",
+		.of_match_table = sifive_dmc_of_match,
+		.suppress_bind_attrs = true,
+	},
+};
+
+static int __init sifive_dmc_init(void)
+{
+	return platform_driver_register(&sifive_dmc_driver);
+}
+arch_initcall(sifive_dmc_init);
-- 
2.17.1