From: Lina Iyer <lina.iyer@linaro.org> To: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>, "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>, "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>, Mark Rutland <Mark.Rutland@arm.com>, Sudeep Holla <Sudeep.Holla@arm.com>, Catalin Marinas <Catalin.Marinas@arm.com>, Charles Garcia-Tobin <Charles.Garcia-Tobin@arm.com>, Nicolas Pitre <nico@linaro.org>, Rob Herring <robh+dt@kernel.org>, "grant.likely@linaro.org" <grant.likely@linaro.org>, Peter De Schrijver <pdeschrijver@nvidia.com>, Santosh Shilimkar <santosh.shilimkar@ti.com>, Daniel Lezcano <daniel.lezcano@linaro.org>, Amit Kucheria <amit.kucheria@linaro.org>, Vincent Guittot <vincent.guittot@linaro.org>, Antti Miettinen <ananaza@iki.fi>, Stephen Boyd <sboyd@codeaurora.org>, Kevin Hilman <khilman@linaro.org>, Sebastian Capella <sebcape@gmail.com>, Tomasz Figa <t.figa@sam> Subject: Re: [PATCH v8 4/8] arm64: kernel: introduce cpu_init_idle CPU operation Date: Wed, 3 Sep 2014 13:16:01 -0600 [thread overview] Message-ID: <20140903191601.GJ92149@ilina-mac.local> (raw) In-Reply-To: <20140903174645.GK1824@e102568-lin.cambridge.arm.com> On Wed, Sep 03 2014 at 11:46 -0600, Lorenzo Pieralisi wrote: >On Wed, Sep 03, 2014 at 06:34:37PM +0100, Lina Iyer wrote: >> On Mon, Sep 01 2014 at 09:28 -0600, Lorenzo Pieralisi wrote: >> >The CPUidle subsystem on ARM64 machines requires the idle states >> >implementation back-end to initialize idle states parameter upon >> >boot. This patch adds a hook in the CPU operations structure that >> >should be initialized by the CPU operations back-end in order to >> >provide a function that initializes cpu idle states. >> > >> >This patch also adds the infrastructure to arm64 kernel required >> >to export the CPU operations based initialization interface, so >> >that drivers (ie CPUidle) can use it when they are initialized >> >at probe time. >> > >> I like the change for ARM64. >> However, that raises a question, how do I have the same driver that >> should get probed by a platform device (on 32 bit ARM) and getting called >> from cpu_init_idle on ARM64? > >I am not following you sorry. The ARM64 CPUidle driver calls the arm64 >cpu_init_idle hooks to initialize idle states (in a generic way from >a driver perspective), not the other way around. > >On ARM64 your idle driver rely on an arm64 suspend back-end (eg PSCI) to >enter idle states, it works in a different way from ARM, on purpose. > >Have a look at what the code does, it won't be the same driver that's >for certain, since on arm64 I do not want to cope with per-platform >CPUidle state enter functions anymore, the arm64 cpu_ops suspend hook >implements the idle state enter method. Ah, I was working on the premise that I may be using the same cpuidle driver for ARM64. I guess I will worry about ARM64 with non-PSCI drivers when and if I have to. Thanks! > >Lorenzo > >> >Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> >> >Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> >> >--- >> > arch/arm64/include/asm/cpu_ops.h | 3 +++ >> > arch/arm64/include/asm/cpuidle.h | 13 +++++++++++++ >> > arch/arm64/kernel/Makefile | 1 + >> > arch/arm64/kernel/cpuidle.c | 31 +++++++++++++++++++++++++++++++ >> > 4 files changed, 48 insertions(+) >> > create mode 100644 arch/arm64/include/asm/cpuidle.h >> > create mode 100644 arch/arm64/kernel/cpuidle.c >> > >> >diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h >> >index d7b4b38..47dfa31 100644 >> >--- a/arch/arm64/include/asm/cpu_ops.h >> >+++ b/arch/arm64/include/asm/cpu_ops.h >> >@@ -28,6 +28,8 @@ struct device_node; >> > * enable-method property. >> > * @cpu_init: Reads any data necessary for a specific enable-method from the >> > * devicetree, for a given cpu node and proposed logical id. >> >+ * @cpu_init_idle: Reads any data necessary to initialize CPU idle states from >> >+ * devicetree, for a given cpu node and proposed logical id. >> > * @cpu_prepare: Early one-time preparation step for a cpu. If there is a >> > * mechanism for doing so, tests whether it is possible to boot >> > * the given CPU. >> >@@ -47,6 +49,7 @@ struct device_node; >> > struct cpu_operations { >> > const char *name; >> > int (*cpu_init)(struct device_node *, unsigned int); >> >+ int (*cpu_init_idle)(struct device_node *, unsigned int); >> > int (*cpu_prepare)(unsigned int); >> > int (*cpu_boot)(unsigned int); >> > void (*cpu_postboot)(void); >> >diff --git a/arch/arm64/include/asm/cpuidle.h b/arch/arm64/include/asm/cpuidle.h >> >new file mode 100644 >> >index 0000000..b52a993 >> >--- /dev/null >> >+++ b/arch/arm64/include/asm/cpuidle.h >> >@@ -0,0 +1,13 @@ >> >+#ifndef __ASM_CPUIDLE_H >> >+#define __ASM_CPUIDLE_H >> >+ >> >+#ifdef CONFIG_CPU_IDLE >> >+extern int cpu_init_idle(unsigned int cpu); >> >+#else >> >+static inline int cpu_init_idle(unsigned int cpu) >> >+{ >> >+ return -EOPNOTSUPP; >> >+} >> >+#endif >> >+ >> >+#endif >> >diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile >> >index 383d81d..be78980 100644 >> >--- a/arch/arm64/kernel/Makefile >> >+++ b/arch/arm64/kernel/Makefile >> >@@ -27,6 +27,7 @@ arm64-obj-$(CONFIG_PERF_EVENTS) += perf_regs.o >> > arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o >> > arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o >> > arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o >> >+arm64-obj-$(CONFIG_CPU_IDLE) += cpuidle.o >> > arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o >> > arm64-obj-$(CONFIG_KGDB) += kgdb.o >> > arm64-obj-$(CONFIG_EFI) += efi.o efi-stub.o efi-entry.o >> >diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c >> >new file mode 100644 >> >index 0000000..19d17f5 >> >--- /dev/null >> >+++ b/arch/arm64/kernel/cpuidle.c >> >@@ -0,0 +1,31 @@ >> >+/* >> >+ * ARM64 CPU idle arch support >> >+ * >> >+ * Copyright (C) 2014 ARM Ltd. >> >+ * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> >> >+ * >> >+ * This program is free software; you can redistribute it and/or modify >> >+ * it under the terms of the GNU General Public License version 2 as >> >+ * published by the Free Software Foundation. >> >+ */ >> >+ >> >+#include <linux/of.h> >> >+#include <linux/of_device.h> >> >+ >> >+#include <asm/cpuidle.h> >> >+#include <asm/cpu_ops.h> >> >+ >> >+int cpu_init_idle(unsigned int cpu) >> >+{ >> >+ int ret = -EOPNOTSUPP; >> >+ struct device_node *cpu_node = of_cpu_device_node_get(cpu); >> >+ >> >+ if (!cpu_node) >> >+ return -ENODEV; >> >+ >> >+ if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_init_idle) >> >+ ret = cpu_ops[cpu]->cpu_init_idle(cpu_node, cpu); >> >+ >> >+ of_node_put(cpu_node); >> >+ return ret; >> >+} >> >-- >> >1.9.1 >> > >> > >> -- >> To unsubscribe from this list: send the line "unsubscribe devicetree" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >
WARNING: multiple messages have this Message-ID (diff)
From: lina.iyer@linaro.org (Lina Iyer) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v8 4/8] arm64: kernel: introduce cpu_init_idle CPU operation Date: Wed, 3 Sep 2014 13:16:01 -0600 [thread overview] Message-ID: <20140903191601.GJ92149@ilina-mac.local> (raw) In-Reply-To: <20140903174645.GK1824@e102568-lin.cambridge.arm.com> On Wed, Sep 03 2014 at 11:46 -0600, Lorenzo Pieralisi wrote: >On Wed, Sep 03, 2014 at 06:34:37PM +0100, Lina Iyer wrote: >> On Mon, Sep 01 2014 at 09:28 -0600, Lorenzo Pieralisi wrote: >> >The CPUidle subsystem on ARM64 machines requires the idle states >> >implementation back-end to initialize idle states parameter upon >> >boot. This patch adds a hook in the CPU operations structure that >> >should be initialized by the CPU operations back-end in order to >> >provide a function that initializes cpu idle states. >> > >> >This patch also adds the infrastructure to arm64 kernel required >> >to export the CPU operations based initialization interface, so >> >that drivers (ie CPUidle) can use it when they are initialized >> >at probe time. >> > >> I like the change for ARM64. >> However, that raises a question, how do I have the same driver that >> should get probed by a platform device (on 32 bit ARM) and getting called >> from cpu_init_idle on ARM64? > >I am not following you sorry. The ARM64 CPUidle driver calls the arm64 >cpu_init_idle hooks to initialize idle states (in a generic way from >a driver perspective), not the other way around. > >On ARM64 your idle driver rely on an arm64 suspend back-end (eg PSCI) to >enter idle states, it works in a different way from ARM, on purpose. > >Have a look at what the code does, it won't be the same driver that's >for certain, since on arm64 I do not want to cope with per-platform >CPUidle state enter functions anymore, the arm64 cpu_ops suspend hook >implements the idle state enter method. Ah, I was working on the premise that I may be using the same cpuidle driver for ARM64. I guess I will worry about ARM64 with non-PSCI drivers when and if I have to. Thanks! > >Lorenzo > >> >Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> >> >Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> >> >--- >> > arch/arm64/include/asm/cpu_ops.h | 3 +++ >> > arch/arm64/include/asm/cpuidle.h | 13 +++++++++++++ >> > arch/arm64/kernel/Makefile | 1 + >> > arch/arm64/kernel/cpuidle.c | 31 +++++++++++++++++++++++++++++++ >> > 4 files changed, 48 insertions(+) >> > create mode 100644 arch/arm64/include/asm/cpuidle.h >> > create mode 100644 arch/arm64/kernel/cpuidle.c >> > >> >diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h >> >index d7b4b38..47dfa31 100644 >> >--- a/arch/arm64/include/asm/cpu_ops.h >> >+++ b/arch/arm64/include/asm/cpu_ops.h >> >@@ -28,6 +28,8 @@ struct device_node; >> > * enable-method property. >> > * @cpu_init: Reads any data necessary for a specific enable-method from the >> > * devicetree, for a given cpu node and proposed logical id. >> >+ * @cpu_init_idle: Reads any data necessary to initialize CPU idle states from >> >+ * devicetree, for a given cpu node and proposed logical id. >> > * @cpu_prepare: Early one-time preparation step for a cpu. If there is a >> > * mechanism for doing so, tests whether it is possible to boot >> > * the given CPU. >> >@@ -47,6 +49,7 @@ struct device_node; >> > struct cpu_operations { >> > const char *name; >> > int (*cpu_init)(struct device_node *, unsigned int); >> >+ int (*cpu_init_idle)(struct device_node *, unsigned int); >> > int (*cpu_prepare)(unsigned int); >> > int (*cpu_boot)(unsigned int); >> > void (*cpu_postboot)(void); >> >diff --git a/arch/arm64/include/asm/cpuidle.h b/arch/arm64/include/asm/cpuidle.h >> >new file mode 100644 >> >index 0000000..b52a993 >> >--- /dev/null >> >+++ b/arch/arm64/include/asm/cpuidle.h >> >@@ -0,0 +1,13 @@ >> >+#ifndef __ASM_CPUIDLE_H >> >+#define __ASM_CPUIDLE_H >> >+ >> >+#ifdef CONFIG_CPU_IDLE >> >+extern int cpu_init_idle(unsigned int cpu); >> >+#else >> >+static inline int cpu_init_idle(unsigned int cpu) >> >+{ >> >+ return -EOPNOTSUPP; >> >+} >> >+#endif >> >+ >> >+#endif >> >diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile >> >index 383d81d..be78980 100644 >> >--- a/arch/arm64/kernel/Makefile >> >+++ b/arch/arm64/kernel/Makefile >> >@@ -27,6 +27,7 @@ arm64-obj-$(CONFIG_PERF_EVENTS) += perf_regs.o >> > arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o >> > arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o >> > arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o >> >+arm64-obj-$(CONFIG_CPU_IDLE) += cpuidle.o >> > arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o >> > arm64-obj-$(CONFIG_KGDB) += kgdb.o >> > arm64-obj-$(CONFIG_EFI) += efi.o efi-stub.o efi-entry.o >> >diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c >> >new file mode 100644 >> >index 0000000..19d17f5 >> >--- /dev/null >> >+++ b/arch/arm64/kernel/cpuidle.c >> >@@ -0,0 +1,31 @@ >> >+/* >> >+ * ARM64 CPU idle arch support >> >+ * >> >+ * Copyright (C) 2014 ARM Ltd. >> >+ * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> >> >+ * >> >+ * This program is free software; you can redistribute it and/or modify >> >+ * it under the terms of the GNU General Public License version 2 as >> >+ * published by the Free Software Foundation. >> >+ */ >> >+ >> >+#include <linux/of.h> >> >+#include <linux/of_device.h> >> >+ >> >+#include <asm/cpuidle.h> >> >+#include <asm/cpu_ops.h> >> >+ >> >+int cpu_init_idle(unsigned int cpu) >> >+{ >> >+ int ret = -EOPNOTSUPP; >> >+ struct device_node *cpu_node = of_cpu_device_node_get(cpu); >> >+ >> >+ if (!cpu_node) >> >+ return -ENODEV; >> >+ >> >+ if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_init_idle) >> >+ ret = cpu_ops[cpu]->cpu_init_idle(cpu_node, cpu); >> >+ >> >+ of_node_put(cpu_node); >> >+ return ret; >> >+} >> >-- >> >1.9.1 >> > >> > >> -- >> To unsubscribe from this list: send the line "unsubscribe devicetree" in >> the body of a message to majordomo at vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >
next prev parent reply other threads:[~2014-09-03 19:16 UTC|newest] Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top 2014-09-01 15:28 [PATCH v8 0/8] ARM generic idle states Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-01 15:28 ` [PATCH v8 1/8] arm64: kernel: refactor the CPU suspend API for retention states Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi [not found] ` <1409585324-3678-1-git-send-email-lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org> 2014-09-01 15:28 ` [PATCH v8 2/8] Documentation: arm: define DT idle states bindings Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-01 15:28 ` [PATCH v8 3/8] drivers: cpuidle: implement DT based idle states infrastructure Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-03 13:25 ` Daniel Lezcano 2014-09-03 13:25 ` Daniel Lezcano 2014-09-03 17:30 ` Lorenzo Pieralisi 2014-09-03 17:30 ` Lorenzo Pieralisi 2014-09-01 15:28 ` [PATCH v8 4/8] arm64: kernel: introduce cpu_init_idle CPU operation Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-03 17:34 ` Lina Iyer 2014-09-03 17:34 ` Lina Iyer 2014-09-03 17:46 ` Lorenzo Pieralisi 2014-09-03 17:46 ` Lorenzo Pieralisi 2014-09-03 19:16 ` Lina Iyer [this message] 2014-09-03 19:16 ` Lina Iyer 2014-09-01 15:28 ` [PATCH v8 5/8] arm64: add PSCI CPU_SUSPEND based cpu_suspend support Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-01 15:28 ` [PATCH v8 6/8] drivers: cpuidle: CPU idle ARM64 driver Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-03 17:37 ` Lorenzo Pieralisi 2014-09-03 17:37 ` Lorenzo Pieralisi 2014-09-04 16:03 ` Catalin Marinas 2014-09-04 16:03 ` Catalin Marinas 2014-09-04 17:29 ` Lorenzo Pieralisi 2014-09-04 17:29 ` Lorenzo Pieralisi 2014-09-05 9:21 ` Will Deacon 2014-09-05 9:21 ` Will Deacon 2014-09-05 15:34 ` Lorenzo Pieralisi 2014-09-05 15:34 ` Lorenzo Pieralisi 2014-09-11 8:28 ` Daniel Lezcano 2014-09-11 8:28 ` Daniel Lezcano 2014-09-11 8:57 ` Lorenzo Pieralisi 2014-09-11 8:57 ` Lorenzo Pieralisi [not found] ` <20140911085727.GA25773-7AyDDHkRsp3ZROr8t4l/smS4ubULX0JqMm0uRHvK7Nw@public.gmane.org> 2014-09-11 9:32 ` Daniel Lezcano 2014-09-11 9:32 ` Daniel Lezcano 2014-09-12 10:32 ` Catalin Marinas 2014-09-12 10:32 ` Catalin Marinas 2014-09-12 11:26 ` Lorenzo Pieralisi 2014-09-12 11:26 ` Lorenzo Pieralisi 2014-09-23 13:35 ` Bartlomiej Zolnierkiewicz 2014-09-23 13:35 ` Bartlomiej Zolnierkiewicz 2014-09-23 18:14 ` Lorenzo Pieralisi 2014-09-23 18:14 ` Lorenzo Pieralisi 2014-09-14 16:59 ` Tomasz Figa 2014-09-14 16:59 ` Tomasz Figa 2014-09-23 13:42 ` Bartlomiej Zolnierkiewicz 2014-09-23 13:42 ` Bartlomiej Zolnierkiewicz 2014-09-23 18:16 ` Lorenzo Pieralisi 2014-09-23 18:16 ` Lorenzo Pieralisi 2014-09-29 11:08 ` Lorenzo Pieralisi 2014-09-29 11:08 ` Lorenzo Pieralisi 2014-09-01 15:28 ` [PATCH v8 7/8] drivers: cpuidle: initialize big.LITTLE driver through DT Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-03 13:29 ` Daniel Lezcano 2014-09-03 13:29 ` Daniel Lezcano 2014-09-01 15:28 ` [PATCH v8 8/8] drivers: cpuidle: initialize Exynos " Lorenzo Pieralisi 2014-09-01 15:28 ` Lorenzo Pieralisi 2014-09-03 13:32 ` Daniel Lezcano 2014-09-03 13:32 ` Daniel Lezcano 2014-09-03 17:29 ` Lorenzo Pieralisi 2014-09-03 17:29 ` Lorenzo Pieralisi
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