From mboxrd@z Thu Jan 1 00:00:00 1970 From: amit.daniel@samsung.com (Amit Daniel Kachhap) Date: Thu, 30 Oct 2014 09:25:38 +0530 Subject: [PATCH 3/3] arm64: psci: Add support to call cpu_suspend with deepest C state. In-Reply-To: <1414641338-25279-1-git-send-email-amit.daniel@samsung.com> References: <1414641338-25279-1-git-send-email-amit.daniel@samsung.com> Message-ID: <1414641338-25279-3-git-send-email-amit.daniel@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This feature will be useful for system suspend/resume which may intend to invoke cpu_suspend with deepest possible C state level. Signed-off-by: Amit Daniel Kachhap --- arch/arm64/include/asm/psci.h | 2 ++ arch/arm64/kernel/psci.c | 8 ++++++++ 2 files changed, 10 insertions(+) diff --git a/arch/arm64/include/asm/psci.h b/arch/arm64/include/asm/psci.h index e5312ea..487e52b 100644 --- a/arch/arm64/include/asm/psci.h +++ b/arch/arm64/include/asm/psci.h @@ -14,6 +14,8 @@ #ifndef __ASM_PSCI_H #define __ASM_PSCI_H +#define CPU_PSCI_IDLE_INDEX_MAX 0xff + int psci_init(void); #endif /* __ASM_PSCI_H */ diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 4ebc146..a761513 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -70,6 +70,7 @@ enum psci_function { static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state); static u32 psci_function_id[PSCI_FN_MAX]; +static u32 cpu_psci_idle_state_count; static int psci_to_linux_errno(int errno) { @@ -239,6 +240,8 @@ static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node, if (!count) return -ENODEV; + cpu_psci_idle_state_count = count; + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); if (!psci_states) return -ENOMEM; @@ -521,6 +524,11 @@ static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index) { int ret; struct psci_power_state *state = __get_cpu_var(psci_power_state); + + /* Check and select the deepest idle state */ + if (index == CPU_PSCI_IDLE_INDEX_MAX) + index = cpu_psci_idle_state_count; + /* * idle state index 0 corresponds to wfi, should never be called * from the cpu_suspend operations. -- 1.9.1