[PATCH 11/12] ARM: migrate to common PSCI client code

[ashwin.chaugule@linaro.org (Ashwin Chaugule)]

On 8 May 2015 at 07:36, Mark Rutland <mark.rutland@arm.com> wrote:
> Now that the common PSCI client code has been factored out to
> drivers/firmware, and made safe for 32-bit use, move the 32-bit ARM code
> over to it. This results in a moderate reduction of duplicated lines,
> and will prevent further duplication as the PSCI client code is updated
> for PSCI 1.0 and beyond.
>
> The two legacy platform users of the PSCI invocation code are updated to
> account for interface changes. In both cases the power state parameter
> is changed to an opaque u32 token in preparation for PSCI 1.0 power
> state changes.
>
> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
> Cc: Ashwin Chaugule <ashwin.chaugule@linaro.org>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Will Deacon <will.deacon@arm.com>
> ---
>  arch/arm/Kconfig                  |   1 +
>  arch/arm/include/asm/psci.h       |  23 ---
>  arch/arm/kernel/Makefile          |   2 +-
>  arch/arm/kernel/psci.c            | 299 --------------------------------------
>  arch/arm/kernel/psci_smp.c        |  29 +++-
>  arch/arm/kernel/setup.c           |   3 +-
>  arch/arm/mach-highbank/highbank.c |   2 +-
>  arch/arm/mach-highbank/pm.c       |   8 +-
>  drivers/cpuidle/cpuidle-calxeda.c |   7 +-
>  9 files changed, 32 insertions(+), 342 deletions(-)
>  delete mode 100644 arch/arm/kernel/psci.c
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 45df48b..191291f 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -1465,6 +1465,7 @@ config HOTPLUG_CPU
>  config ARM_PSCI
>         bool "Support for the ARM Power State Coordination Interface (PSCI)"
>         depends on CPU_V7
> +       select ARM_PSCI_FW
>         help
>           Say Y here if you want Linux to communicate with system firmware
>           implementing the PSCI specification for CPU-centric power
> diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h
> index c25ef3e..68ee3ce 100644
> --- a/arch/arm/include/asm/psci.h
> +++ b/arch/arm/include/asm/psci.h
> @@ -14,34 +14,11 @@
>  #ifndef __ASM_ARM_PSCI_H
>  #define __ASM_ARM_PSCI_H
>
> -#define PSCI_POWER_STATE_TYPE_STANDBY          0
> -#define PSCI_POWER_STATE_TYPE_POWER_DOWN       1
> -
> -struct psci_power_state {
> -       u16     id;
> -       u8      type;
> -       u8      affinity_level;
> -};
> -
> -struct psci_operations {
> -       int (*cpu_suspend)(struct psci_power_state state,
> -                          unsigned long entry_point);
> -       int (*cpu_off)(struct psci_power_state state);
> -       int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
> -       int (*migrate)(unsigned long cpuid);
> -       int (*affinity_info)(unsigned long target_affinity,
> -                       unsigned long lowest_affinity_level);
> -       int (*migrate_info_type)(void);
> -};
> -
> -extern struct psci_operations psci_ops;
>  extern struct smp_operations psci_smp_ops;
>
>  #ifdef CONFIG_ARM_PSCI
> -int psci_init(void);
>  bool psci_smp_available(void);
>  #else
> -static inline int psci_init(void) { return 0; }
>  static inline bool psci_smp_available(void) { return false; }
>  #endif
>
> diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
> index 752725d..2c06383 100644
> --- a/arch/arm/kernel/Makefile
> +++ b/arch/arm/kernel/Makefile
> @@ -86,7 +86,7 @@ obj-$(CONFIG_EARLY_PRINTK)    += early_printk.o
>
>  obj-$(CONFIG_ARM_VIRT_EXT)     += hyp-stub.o
>  ifeq ($(CONFIG_ARM_PSCI),y)
> -obj-y                          += psci.o psci-call.o
> +obj-y                          += psci-call.o
>  obj-$(CONFIG_SMP)              += psci_smp.o
>  endif
>
> diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c
> deleted file mode 100644
> index f90fdf4..0000000
> --- a/arch/arm/kernel/psci.c
> +++ /dev/null
> @@ -1,299 +0,0 @@
> -/*
> - * 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.
> - *
> - * This program is distributed in the hope that it will be useful,
> - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> - * GNU General Public License for more details.
> - *
> - * Copyright (C) 2012 ARM Limited
> - *
> - * Author: Will Deacon <will.deacon@arm.com>
> - */
> -
> -#define pr_fmt(fmt) "psci: " fmt
> -
> -#include <linux/init.h>
> -#include <linux/of.h>
> -#include <linux/reboot.h>
> -#include <linux/pm.h>
> -#include <uapi/linux/psci.h>
> -
> -#include <asm/compiler.h>
> -#include <asm/errno.h>
> -#include <asm/psci.h>
> -#include <asm/system_misc.h>
> -
> -struct psci_operations psci_ops;
> -
> -static int (*invoke_psci_fn)(u32, u32, u32, u32);
> -typedef int (*psci_initcall_t)(const struct device_node *);
> -
> -asmlinkage int __invoke_psci_fn_hvc(u32, u32, u32, u32);
> -asmlinkage int __invoke_psci_fn_smc(u32, u32, u32, u32);
> -
> -enum psci_function {
> -       PSCI_FN_CPU_SUSPEND,
> -       PSCI_FN_CPU_ON,
> -       PSCI_FN_CPU_OFF,
> -       PSCI_FN_MIGRATE,
> -       PSCI_FN_AFFINITY_INFO,
> -       PSCI_FN_MIGRATE_INFO_TYPE,
> -       PSCI_FN_MAX,
> -};
> -
> -static u32 psci_function_id[PSCI_FN_MAX];
> -
> -static int psci_to_linux_errno(int errno)
> -{
> -       switch (errno) {
> -       case PSCI_RET_SUCCESS:
> -               return 0;
> -       case PSCI_RET_NOT_SUPPORTED:
> -               return -EOPNOTSUPP;
> -       case PSCI_RET_INVALID_PARAMS:
> -               return -EINVAL;
> -       case PSCI_RET_DENIED:
> -               return -EPERM;
> -       };
> -
> -       return -EINVAL;
> -}
> -
> -static u32 psci_power_state_pack(struct psci_power_state state)
> -{
> -       return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
> -                       & PSCI_0_2_POWER_STATE_ID_MASK) |
> -               ((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
> -                & PSCI_0_2_POWER_STATE_TYPE_MASK) |
> -               ((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
> -                & PSCI_0_2_POWER_STATE_AFFL_MASK);
> -}
> -
> -static int psci_get_version(void)
> -{
> -       int err;
> -
> -       err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
> -       return err;
> -}
> -
> -static int psci_cpu_suspend(struct psci_power_state state,
> -                           unsigned long entry_point)
> -{
> -       int err;
> -       u32 fn, power_state;
> -
> -       fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
> -       power_state = psci_power_state_pack(state);
> -       err = invoke_psci_fn(fn, power_state, entry_point, 0);
> -       return psci_to_linux_errno(err);
> -}
> -
> -static int psci_cpu_off(struct psci_power_state state)
> -{
> -       int err;
> -       u32 fn, power_state;
> -
> -       fn = psci_function_id[PSCI_FN_CPU_OFF];
> -       power_state = psci_power_state_pack(state);
> -       err = invoke_psci_fn(fn, power_state, 0, 0);
> -       return psci_to_linux_errno(err);
> -}
> -
> -static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
> -{
> -       int err;
> -       u32 fn;
> -
> -       fn = psci_function_id[PSCI_FN_CPU_ON];
> -       err = invoke_psci_fn(fn, cpuid, entry_point, 0);
> -       return psci_to_linux_errno(err);
> -}
> -
> -static int psci_migrate(unsigned long cpuid)
> -{
> -       int err;
> -       u32 fn;
> -
> -       fn = psci_function_id[PSCI_FN_MIGRATE];
> -       err = invoke_psci_fn(fn, cpuid, 0, 0);
> -       return psci_to_linux_errno(err);
> -}
> -
> -static int psci_affinity_info(unsigned long target_affinity,
> -               unsigned long lowest_affinity_level)
> -{
> -       int err;
> -       u32 fn;
> -
> -       fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
> -       err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
> -       return err;
> -}
> -
> -static int psci_migrate_info_type(void)
> -{
> -       int err;
> -       u32 fn;
> -
> -       fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
> -       err = invoke_psci_fn(fn, 0, 0, 0);
> -       return err;
> -}
> -
> -static int get_set_conduit_method(struct device_node *np)
> -{
> -       const char *method;
> -
> -       pr_info("probing for conduit method from DT.\n");
> -
> -       if (of_property_read_string(np, "method", &method)) {
> -               pr_warn("missing \"method\" property\n");
> -               return -ENXIO;
> -       }
> -
> -       if (!strcmp("hvc", method)) {
> -               invoke_psci_fn = __invoke_psci_fn_hvc;
> -       } else if (!strcmp("smc", method)) {
> -               invoke_psci_fn = __invoke_psci_fn_smc;
> -       } else {
> -               pr_warn("invalid \"method\" property: %s\n", method);
> -               return -EINVAL;
> -       }
> -       return 0;
> -}
> -
> -static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
> -{
> -       invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
> -}
> -
> -static void psci_sys_poweroff(void)
> -{
> -       invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
> -}
> -
> -/*
> - * PSCI Function IDs for v0.2+ are well defined so use
> - * standard values.
> - */
> -static int psci_0_2_init(struct device_node *np)
> -{
> -       int err, ver;
> -
> -       err = get_set_conduit_method(np);
> -
> -       if (err)
> -               goto out_put_node;
> -
> -       ver = psci_get_version();
> -
> -       if (ver == PSCI_RET_NOT_SUPPORTED) {
> -               /* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */
> -               pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
> -               err = -EOPNOTSUPP;
> -               goto out_put_node;
> -       } else {
> -               pr_info("PSCIv%d.%d detected in firmware.\n",
> -                               PSCI_VERSION_MAJOR(ver),
> -                               PSCI_VERSION_MINOR(ver));
> -
> -               if (PSCI_VERSION_MAJOR(ver) == 0 &&
> -                               PSCI_VERSION_MINOR(ver) < 2) {
> -                       err = -EINVAL;
> -                       pr_err("Conflicting PSCI version detected.\n");
> -                       goto out_put_node;
> -               }
> -       }
> -
> -       pr_info("Using standard PSCI v0.2 function IDs\n");
> -       psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN_CPU_SUSPEND;
> -       psci_ops.cpu_suspend = psci_cpu_suspend;
> -
> -       psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
> -       psci_ops.cpu_off = psci_cpu_off;
> -
> -       psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_CPU_ON;
> -       psci_ops.cpu_on = psci_cpu_on;
> -
> -       psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_MIGRATE;
> -       psci_ops.migrate = psci_migrate;
> -
> -       psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN_AFFINITY_INFO;
> -       psci_ops.affinity_info = psci_affinity_info;
> -
> -       psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
> -               PSCI_0_2_FN_MIGRATE_INFO_TYPE;
> -       psci_ops.migrate_info_type = psci_migrate_info_type;
> -
> -       arm_pm_restart = psci_sys_reset;
> -
> -       pm_power_off = psci_sys_poweroff;
> -
> -out_put_node:
> -       of_node_put(np);
> -       return err;
> -}
> -
> -/*
> - * PSCI < v0.2 get PSCI Function IDs via DT.
> - */
> -static int psci_0_1_init(struct device_node *np)
> -{
> -       u32 id;
> -       int err;
> -
> -       err = get_set_conduit_method(np);
> -
> -       if (err)
> -               goto out_put_node;
> -
> -       pr_info("Using PSCI v0.1 Function IDs from DT\n");
> -
> -       if (!of_property_read_u32(np, "cpu_suspend", &id)) {
> -               psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
> -               psci_ops.cpu_suspend = psci_cpu_suspend;
> -       }
> -
> -       if (!of_property_read_u32(np, "cpu_off", &id)) {
> -               psci_function_id[PSCI_FN_CPU_OFF] = id;
> -               psci_ops.cpu_off = psci_cpu_off;
> -       }
> -
> -       if (!of_property_read_u32(np, "cpu_on", &id)) {
> -               psci_function_id[PSCI_FN_CPU_ON] = id;
> -               psci_ops.cpu_on = psci_cpu_on;
> -       }
> -
> -       if (!of_property_read_u32(np, "migrate", &id)) {
> -               psci_function_id[PSCI_FN_MIGRATE] = id;
> -               psci_ops.migrate = psci_migrate;
> -       }
> -
> -out_put_node:
> -       of_node_put(np);
> -       return err;
> -}
> -
> -static const struct of_device_id psci_of_match[] __initconst = {
> -       { .compatible = "arm,psci", .data = psci_0_1_init},
> -       { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
> -       {},
> -};
> -
> -int __init psci_init(void)
> -{
> -       struct device_node *np;
> -       const struct of_device_id *matched_np;
> -       psci_initcall_t init_fn;
> -
> -       np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
> -       if (!np)
> -               return -ENODEV;
> -
> -       init_fn = (psci_initcall_t)matched_np->data;
> -       return init_fn(np);
> -}
> diff --git a/arch/arm/kernel/psci_smp.c b/arch/arm/kernel/psci_smp.c
> index 28a1db4..2d4a7255 100644
> --- a/arch/arm/kernel/psci_smp.c
> +++ b/arch/arm/kernel/psci_smp.c
> @@ -17,6 +17,8 @@
>  #include <linux/smp.h>
>  #include <linux/of.h>
>  #include <linux/delay.h>
> +#include <linux/psci.h>
> +
>  #include <uapi/linux/psci.h>
>
>  #include <asm/psci.h>
> @@ -56,17 +58,29 @@ static int psci_boot_secondary(unsigned int cpu, struct task_struct *idle)
>  }
>
>  #ifdef CONFIG_HOTPLUG_CPU
> +int psci_cpu_disable(unsigned int cpu)
> +{
> +       /* Fail early if we don't have CPU_OFF support */
> +       if (!psci_ops.cpu_off)
> +               return 0;
> +
> +       /* Trusted OS will deny CPU_OFF */
> +       if (psci_tos_resident_on(cpu))
> +               return 0;
> +

Same question here. Seems like if MIGRATE_INFO_TYPE = 2 ( TOS is
present or does not require migration), you should be able to call
CPU_OFF. Otherwise the patch looks fine to me.