diff options
Diffstat (limited to 'arch/arm/mach-imx/pm-imx5.c')
| -rw-r--r-- | arch/arm/mach-imx/pm-imx5.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/pm-imx5.c b/arch/arm/mach-imx/pm-imx5.c new file mode 100644 index 00000000000..58aeaf5baaf --- /dev/null +++ b/arch/arm/mach-imx/pm-imx5.c @@ -0,0 +1,177 @@ +/* + * 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 <linux/suspend.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/export.h> +#include <asm/cacheflush.h> +#include <asm/system_misc.h> +#include <asm/tlbflush.h> + +#include "common.h" +#include "cpuidle.h" +#include "crm-regs-imx5.h" +#include "hardware.h" + +/* + * The WAIT_UNCLOCKED_POWER_OFF state only requires <= 500ns to exit. + * This is also the lowest power state possible without affecting + * non-cpu parts of the system. For these reasons, imx5 should default + * to always using this state for cpu idling. The PM_SUSPEND_STANDBY also + * uses this state and needs to take no action when registers remain confgiured + * for this state. + */ +#define IMX5_DEFAULT_CPU_IDLE_STATE WAIT_UNCLOCKED_POWER_OFF + +/* + * set cpu low power mode before WFI instruction. This function is called + * mx5 because it can be used for mx51, and mx53. + */ +static 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; + 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); + __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); + } +} + +static int mx5_suspend_enter(suspend_state_t state) +{ + switch (state) { + case PM_SUSPEND_MEM: + mx5_cpu_lp_set(STOP_POWER_OFF); + break; + case PM_SUSPEND_STANDBY: + /* DEFAULT_IDLE_STATE already configured */ + break; + default: + return -EINVAL; + } + + if (state == PM_SUSPEND_MEM) { + local_flush_tlb_all(); + flush_cache_all(); + + /*clear the EMPGC0/1 bits */ + __raw_writel(0, MXC_SRPG_EMPGC0_SRPGCR); + __raw_writel(0, MXC_SRPG_EMPGC1_SRPGCR); + } + cpu_do_idle(); + + /* return registers to default idle state */ + mx5_cpu_lp_set(IMX5_DEFAULT_CPU_IDLE_STATE); + return 0; +} + +static int mx5_pm_valid(suspend_state_t state) +{ + return (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX); +} + +static const struct platform_suspend_ops mx5_suspend_ops = { + .valid = mx5_pm_valid, + .enter = mx5_suspend_enter, +}; + +static inline int imx5_cpu_do_idle(void) +{ + int ret = tzic_enable_wake(); + + if (likely(!ret)) + cpu_do_idle(); + + return ret; +} + +static void imx5_pm_idle(void) +{ + imx5_cpu_do_idle(); +} + +static int __init imx5_pm_common_init(void) +{ + int ret; + struct clk *gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs"); + + if (IS_ERR(gpc_dvfs_clk)) + return PTR_ERR(gpc_dvfs_clk); + + ret = clk_prepare_enable(gpc_dvfs_clk); + if (ret) + return ret; + + arm_pm_idle = imx5_pm_idle; + + /* Set the registers to the default cpu idle state. */ + mx5_cpu_lp_set(IMX5_DEFAULT_CPU_IDLE_STATE); + + return imx5_cpuidle_init(); +} + +void __init imx5_pm_init(void) +{ + int ret = imx5_pm_common_init(); + if (!ret) + suspend_set_ops(&mx5_suspend_ops); +} |