Merge "arm64: topology: Allow specifying the CPU efficiency from device tree" (0f1b71e7) · Commits · e / devices / android_kernel_xiaomi_markw

Documentation/devicetree/bindings/arm/cpus.txt

+14 −0

Original line number	Diff line number	Diff line
		@@ -210,6 +210,20 @@ nodes to be present and contain the properties described below.
		property identifying a 64-bit zero-initialised
		memory location.

		- efficiency
		Usage: optional.
		Value type: <u32>
		Definition:
		# Specifies the CPU efficiency. The CPU efficiency is
		a unit less number and it is intended to show relative
		performance of CPUs when normalized for clock frequency
		(instructions per cycle performance).

		The efficiency of a CPU can vary across SoCs depending
		on the cache size, bus interconnect frequencies etc.
		This value overrides the default efficiency value
		defined for the corresponding CPU architecture.

		- qcom,saw
		Usage: required for systems that have an "enable-method"
		property value of "qcom,kpss-acc-v1" or

arch/arm/kernel/topology.c

+28 −6

Original line number	Diff line number	Diff line
		@@ -190,6 +190,13 @@ static int __init parse_cluster(struct device_node *cluster, int depth)
		return 0;
		}

		static DEFINE_PER_CPU(unsigned long, cpu_efficiency) = SCHED_CAPACITY_SCALE;

		unsigned long arch_get_cpu_efficiency(int cpu)
		{
		return per_cpu(cpu_efficiency, cpu);
		}

		#ifdef CONFIG_OF
		struct cpu_efficiency {
		const char *compatible;
		@@ -266,6 +273,7 @@ static int __init parse_dt_topology(void)
		for_each_possible_cpu(cpu) {
		const u32 *rate;
		int len;
		u32 efficiency;

		/* too early to use cpu->of_node */
		cn = of_get_cpu_node(cpu, NULL);
		@@ -274,13 +282,27 @@ static int __init parse_dt_topology(void)
		continue;
		}

		for (cpu_eff = table_efficiency; cpu_eff->compatible; cpu_eff++)
		if (of_device_is_compatible(cn, cpu_eff->compatible))
		/*
		* The CPU efficiency value passed from the device tree
		* overrides the value defined in the table_efficiency[]
		*/
		if (of_property_read_u32(cn, "efficiency", &efficiency) < 0) {

		for (cpu_eff = table_efficiency;
		cpu_eff->compatible; cpu_eff++)

		if (of_device_is_compatible(cn,
		cpu_eff->compatible))
		break;

		if (cpu_eff->compatible == NULL)
		continue;

		efficiency = cpu_eff->efficiency;
		}

		per_cpu(cpu_efficiency, cpu) = efficiency;

		rate = of_get_property(cn, "clock-frequency", &len);
		if (!rate \|\| len != 4) {
		pr_err("%s missing clock-frequency property\n",
		@@ -288,7 +310,7 @@ static int __init parse_dt_topology(void)
		continue;
		}

		capacity = ((be32_to_cpup(rate)) >> 20) * cpu_eff->efficiency;
		capacity = ((be32_to_cpup(rate)) >> 20) * efficiency;

		/* Save min capacity of the system */
		if (capacity < min_capacity)

arch/arm64/kernel/topology.c

+22 −8

Original line number	Diff line number	Diff line
		@@ -280,6 +280,7 @@ static void __init parse_dt_cpu_power(void)
		for_each_possible_cpu(cpu) {
		const u32 *rate;
		int len;
		u32 efficiency;

		/* Too early to use cpu->of_node */
		cn = of_get_cpu_node(cpu, NULL);
		@@ -288,16 +289,29 @@ static void __init parse_dt_cpu_power(void)
		continue;
		}

		for (cpu_eff = table_efficiency; cpu_eff->compatible; cpu_eff++)
		if (of_device_is_compatible(cn, cpu_eff->compatible))
		/*
		* The CPU efficiency value passed from the device tree
		* overrides the value defined in the table_efficiency[]
		*/
		if (of_property_read_u32(cn, "efficiency", &efficiency) < 0) {

		for (cpu_eff = table_efficiency;
		cpu_eff->compatible; cpu_eff++)

		if (of_device_is_compatible(cn,
		cpu_eff->compatible))
		break;

		if (cpu_eff->compatible == NULL) {
		pr_warn("%s: Unknown CPU type\n", cn->full_name);
		pr_warn("%s: Unknown CPU type\n",
		cn->full_name);
		continue;
		}

		per_cpu(cpu_efficiency, cpu) = cpu_eff->efficiency;
		efficiency = cpu_eff->efficiency;
		}

		per_cpu(cpu_efficiency, cpu) = efficiency;

		rate = of_get_property(cn, "clock-frequency", &len);
		if (!rate \|\| len != 4) {
		@@ -306,7 +320,7 @@ static void __init parse_dt_cpu_power(void)
		continue;
		}

		capacity = ((be32_to_cpup(rate)) >> 20) * cpu_eff->efficiency;
		capacity = ((be32_to_cpup(rate)) >> 20) * efficiency;

		/* Save min capacity of the system */
		if (capacity < min_capacity)