From mboxrd@z Thu Jan 1 00:00:00 1970 From: josephl@nvidia.com (Joseph Lo) Date: Fri, 19 Jul 2013 17:25:25 +0800 Subject: [PATCH V4 3/4] ARM: tegra114: add low level support for CPU idle powered-down mode In-Reply-To: <1374225926-26832-1-git-send-email-josephl@nvidia.com> References: <1374225926-26832-1-git-send-email-josephl@nvidia.com> Message-ID: <1374225926-26832-4-git-send-email-josephl@nvidia.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The flow controller would take care the power sequence when CPU idle in powered-down mode. It powered gate the CPU when CPU runs into WFI instruction. And wake up the CPU when event be triggered. The sequence is below. * setting wfi bitmap for the CPU as the halt event in the FLOW_CTRL_CPU_HALT_REG to monitor the CPU running into WFI,then power gate it * setting IRQ and FIQ as wake up event to wake up CPU when event triggered Signed-off-by: Joseph Lo --- V4: * no change V3: * no change V2: * no change --- arch/arm/mach-tegra/flowctrl.h | 2 ++ arch/arm/mach-tegra/sleep-tegra30.S | 2 ++ 2 files changed, 4 insertions(+) diff --git a/arch/arm/mach-tegra/flowctrl.h b/arch/arm/mach-tegra/flowctrl.h index 7a29bae..e56a950 100644 --- a/arch/arm/mach-tegra/flowctrl.h +++ b/arch/arm/mach-tegra/flowctrl.h @@ -28,6 +28,8 @@ #define FLOW_CTRL_SCLK_RESUME (1 << 27) #define FLOW_CTRL_HALT_CPU_IRQ (1 << 10) #define FLOW_CTRL_HALT_CPU_FIQ (1 << 8) +#define FLOW_CTRL_HALT_GIC_IRQ (1 << 9) +#define FLOW_CTRL_HALT_GIC_FIQ (1 << 8) #define FLOW_CTRL_CPU0_CSR 0x8 #define FLOW_CTRL_CSR_INTR_FLAG (1 << 15) #define FLOW_CTRL_CSR_EVENT_FLAG (1 << 14) diff --git a/arch/arm/mach-tegra/sleep-tegra30.S b/arch/arm/mach-tegra/sleep-tegra30.S index ada8821..5877f26 100644 --- a/arch/arm/mach-tegra/sleep-tegra30.S +++ b/arch/arm/mach-tegra/sleep-tegra30.S @@ -99,6 +99,8 @@ flow_ctrl_setting_for_lp2: cmp r10, #TEGRA30 moveq r3, #FLOW_CTRL_WAIT_FOR_INTERRUPT @ For LP2 movne r3, #FLOW_CTRL_WAITEVENT + orrne r3, r3, #FLOW_CTRL_HALT_GIC_IRQ + orrne r3, r3, #FLOW_CTRL_HALT_GIC_FIQ flow_ctrl_done: cmp r10, #TEGRA30 str r3, [r2] -- 1.8.3.2