From 0adf882b6894cd150392400e9642787cf691016a Mon Sep 17 00:00:00 2001 From: Dinh Nguyen Date: Mon, 21 Mar 2011 16:30:37 -0500 Subject: [PATCH] ARM: mx51: Implement code to allow mx51 to enter WFI Implement code for MX51 that allows the SoC to enter WFI when arch_idle is called. This patch is also necessary for correctly suspending the system. Signed-off-by: Dinh Nguyen Signed-off-by: Sascha Hauer --- arch/arm/mach-mx5/Makefile | 2 +- arch/arm/mach-mx5/system.c | 84 +++++++++++++++++++++++++ arch/arm/plat-mxc/include/mach/mxc.h | 9 +++ arch/arm/plat-mxc/include/mach/system.h | 6 +- 4 files changed, 99 insertions(+), 2 deletions(-) create mode 100644 arch/arm/mach-mx5/system.c diff --git a/arch/arm/mach-mx5/Makefile b/arch/arm/mach-mx5/Makefile index 4f63048be3ca..0b9338cec516 100644 --- a/arch/arm/mach-mx5/Makefile +++ b/arch/arm/mach-mx5/Makefile @@ -3,7 +3,7 @@ # # Object file lists. -obj-y := cpu.o mm.o clock-mx51-mx53.o devices.o ehci.o +obj-y := cpu.o mm.o clock-mx51-mx53.o devices.o ehci.o system.o obj-$(CONFIG_SOC_IMX50) += mm-mx50.o obj-$(CONFIG_CPU_FREQ_IMX) += cpu_op-mx51.o diff --git a/arch/arm/mach-mx5/system.c b/arch/arm/mach-mx5/system.c new file mode 100644 index 000000000000..76ae8dc33e00 --- /dev/null +++ b/arch/arm/mach-mx5/system.c @@ -0,0 +1,84 @@ +/* + * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ +#include +#include +#include +#include "crm_regs.h" + +/* set cpu low power mode before WFI instruction. This function is called + * mx5 because it can be used for mx50, mx51, and mx53.*/ +void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode) +{ + u32 plat_lpc, arm_srpgcr, ccm_clpcr; + u32 empgc0, empgc1; + int stop_mode = 0; + + /* always allow platform to issue a deep sleep mode request */ + plat_lpc = __raw_readl(MXC_CORTEXA8_PLAT_LPC) & + ~(MXC_CORTEXA8_PLAT_LPC_DSM); + ccm_clpcr = __raw_readl(MXC_CCM_CLPCR) & ~(MXC_CCM_CLPCR_LPM_MASK); + arm_srpgcr = __raw_readl(MXC_SRPG_ARM_SRPGCR) & ~(MXC_SRPGCR_PCR); + empgc0 = __raw_readl(MXC_SRPG_EMPGC0_SRPGCR) & ~(MXC_SRPGCR_PCR); + empgc1 = __raw_readl(MXC_SRPG_EMPGC1_SRPGCR) & ~(MXC_SRPGCR_PCR); + + switch (mode) { + case WAIT_CLOCKED: + break; + case WAIT_UNCLOCKED: + ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET; + break; + case WAIT_UNCLOCKED_POWER_OFF: + case STOP_POWER_OFF: + plat_lpc |= MXC_CORTEXA8_PLAT_LPC_DSM + | MXC_CORTEXA8_PLAT_LPC_DBG_DSM; + if (mode == WAIT_UNCLOCKED_POWER_OFF) { + ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET; + ccm_clpcr &= ~MXC_CCM_CLPCR_VSTBY; + ccm_clpcr &= ~MXC_CCM_CLPCR_SBYOS; + stop_mode = 0; + } else { + ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET; + ccm_clpcr |= 0x3 << MXC_CCM_CLPCR_STBY_COUNT_OFFSET; + ccm_clpcr |= MXC_CCM_CLPCR_VSTBY; + ccm_clpcr |= MXC_CCM_CLPCR_SBYOS; + stop_mode = 1; + } + arm_srpgcr |= MXC_SRPGCR_PCR; + + if (tzic_enable_wake(1) != 0) + return; + break; + case STOP_POWER_ON: + ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET; + break; + default: + printk(KERN_WARNING "UNKNOWN cpu power mode: %d\n", mode); + return; + } + + __raw_writel(plat_lpc, MXC_CORTEXA8_PLAT_LPC); + __raw_writel(ccm_clpcr, MXC_CCM_CLPCR); + __raw_writel(arm_srpgcr, MXC_SRPG_ARM_SRPGCR); + + /* Enable NEON SRPG for all but MX50TO1.0. */ + if (mx50_revision() != IMX_CHIP_REVISION_1_0) + __raw_writel(arm_srpgcr, MXC_SRPG_NEON_SRPGCR); + + if (stop_mode) { + empgc0 |= MXC_SRPGCR_PCR; + empgc1 |= MXC_SRPGCR_PCR; + + __raw_writel(empgc0, MXC_SRPG_EMPGC0_SRPGCR); + __raw_writel(empgc1, MXC_SRPG_EMPGC1_SRPGCR); + } +} diff --git a/arch/arm/plat-mxc/include/mach/mxc.h b/arch/arm/plat-mxc/include/mach/mxc.h index 3322c7a79c57..1aea818d9d31 100644 --- a/arch/arm/plat-mxc/include/mach/mxc.h +++ b/arch/arm/plat-mxc/include/mach/mxc.h @@ -195,6 +195,15 @@ struct cpu_op { u32 cpu_rate; }; +int tzic_enable_wake(int is_idle); +enum mxc_cpu_pwr_mode { + WAIT_CLOCKED, /* wfi only */ + WAIT_UNCLOCKED, /* WAIT */ + WAIT_UNCLOCKED_POWER_OFF, /* WAIT + SRPG */ + STOP_POWER_ON, /* just STOP */ + STOP_POWER_OFF, /* STOP + SRPG */ +}; + extern struct cpu_op *(*get_cpu_op)(int *op); #endif diff --git a/arch/arm/plat-mxc/include/mach/system.h b/arch/arm/plat-mxc/include/mach/system.h index 95be51bfe9a9..0417da9f710d 100644 --- a/arch/arm/plat-mxc/include/mach/system.h +++ b/arch/arm/plat-mxc/include/mach/system.h @@ -20,6 +20,8 @@ #include #include +extern void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode); + static inline void arch_idle(void) { #ifdef CONFIG_ARCH_MXC91231 @@ -54,7 +56,9 @@ static inline void arch_idle(void) "orr %0, %0, #0x00000004\n" "mcr p15, 0, %0, c1, c0, 0\n" : "=r" (reg)); - } else + } else if (cpu_is_mx51()) + mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF); + else cpu_do_idle(); } -- 2.34.1