Sascha Hauer | 784a90c | 2011-11-07 12:36:48 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved. |
| 3 | * |
| 4 | * The code contained herein is licensed under the GNU General Public |
| 5 | * License. You may obtain a copy of the GNU General Public License |
| 6 | * Version 2 or later at the following locations: |
| 7 | * |
| 8 | * http://www.opensource.org/licenses/gpl-license.html |
| 9 | * http://www.gnu.org/copyleft/gpl.html |
| 10 | */ |
| 11 | #include <linux/suspend.h> |
| 12 | #include <linux/clk.h> |
| 13 | #include <linux/io.h> |
| 14 | #include <linux/err.h> |
| 15 | #include <asm/cacheflush.h> |
| 16 | #include <asm/tlbflush.h> |
| 17 | #include <mach/common.h> |
| 18 | #include <mach/hardware.h> |
| 19 | #include "crm-regs-imx5.h" |
| 20 | |
| 21 | static struct clk *gpc_dvfs_clk; |
| 22 | |
| 23 | /* |
| 24 | * set cpu low power mode before WFI instruction. This function is called |
| 25 | * mx5 because it can be used for mx50, mx51, and mx53. |
| 26 | */ |
| 27 | void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode) |
| 28 | { |
| 29 | u32 plat_lpc, arm_srpgcr, ccm_clpcr; |
| 30 | u32 empgc0, empgc1; |
| 31 | int stop_mode = 0; |
| 32 | |
| 33 | /* always allow platform to issue a deep sleep mode request */ |
| 34 | plat_lpc = __raw_readl(MXC_CORTEXA8_PLAT_LPC) & |
| 35 | ~(MXC_CORTEXA8_PLAT_LPC_DSM); |
| 36 | ccm_clpcr = __raw_readl(MXC_CCM_CLPCR) & ~(MXC_CCM_CLPCR_LPM_MASK); |
| 37 | arm_srpgcr = __raw_readl(MXC_SRPG_ARM_SRPGCR) & ~(MXC_SRPGCR_PCR); |
| 38 | empgc0 = __raw_readl(MXC_SRPG_EMPGC0_SRPGCR) & ~(MXC_SRPGCR_PCR); |
| 39 | empgc1 = __raw_readl(MXC_SRPG_EMPGC1_SRPGCR) & ~(MXC_SRPGCR_PCR); |
| 40 | |
| 41 | switch (mode) { |
| 42 | case WAIT_CLOCKED: |
| 43 | break; |
| 44 | case WAIT_UNCLOCKED: |
| 45 | ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET; |
| 46 | break; |
| 47 | case WAIT_UNCLOCKED_POWER_OFF: |
| 48 | case STOP_POWER_OFF: |
| 49 | plat_lpc |= MXC_CORTEXA8_PLAT_LPC_DSM |
| 50 | | MXC_CORTEXA8_PLAT_LPC_DBG_DSM; |
| 51 | if (mode == WAIT_UNCLOCKED_POWER_OFF) { |
| 52 | ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET; |
| 53 | ccm_clpcr &= ~MXC_CCM_CLPCR_VSTBY; |
| 54 | ccm_clpcr &= ~MXC_CCM_CLPCR_SBYOS; |
| 55 | stop_mode = 0; |
| 56 | } else { |
| 57 | ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET; |
| 58 | ccm_clpcr |= 0x3 << MXC_CCM_CLPCR_STBY_COUNT_OFFSET; |
| 59 | ccm_clpcr |= MXC_CCM_CLPCR_VSTBY; |
| 60 | ccm_clpcr |= MXC_CCM_CLPCR_SBYOS; |
| 61 | stop_mode = 1; |
| 62 | } |
| 63 | arm_srpgcr |= MXC_SRPGCR_PCR; |
Sascha Hauer | 784a90c | 2011-11-07 12:36:48 +0100 | [diff] [blame] | 64 | break; |
| 65 | case STOP_POWER_ON: |
| 66 | ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET; |
| 67 | break; |
| 68 | default: |
| 69 | printk(KERN_WARNING "UNKNOWN cpu power mode: %d\n", mode); |
| 70 | return; |
| 71 | } |
| 72 | |
| 73 | __raw_writel(plat_lpc, MXC_CORTEXA8_PLAT_LPC); |
| 74 | __raw_writel(ccm_clpcr, MXC_CCM_CLPCR); |
| 75 | __raw_writel(arm_srpgcr, MXC_SRPG_ARM_SRPGCR); |
| 76 | |
| 77 | /* Enable NEON SRPG for all but MX50TO1.0. */ |
| 78 | if (mx50_revision() != IMX_CHIP_REVISION_1_0) |
| 79 | __raw_writel(arm_srpgcr, MXC_SRPG_NEON_SRPGCR); |
| 80 | |
| 81 | if (stop_mode) { |
| 82 | empgc0 |= MXC_SRPGCR_PCR; |
| 83 | empgc1 |= MXC_SRPGCR_PCR; |
| 84 | |
| 85 | __raw_writel(empgc0, MXC_SRPG_EMPGC0_SRPGCR); |
| 86 | __raw_writel(empgc1, MXC_SRPG_EMPGC1_SRPGCR); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | static int mx5_suspend_prepare(void) |
| 91 | { |
| 92 | return clk_enable(gpc_dvfs_clk); |
| 93 | } |
| 94 | |
| 95 | static int mx5_suspend_enter(suspend_state_t state) |
| 96 | { |
| 97 | switch (state) { |
| 98 | case PM_SUSPEND_MEM: |
| 99 | mx5_cpu_lp_set(STOP_POWER_OFF); |
| 100 | break; |
| 101 | case PM_SUSPEND_STANDBY: |
| 102 | mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF); |
| 103 | break; |
| 104 | default: |
| 105 | return -EINVAL; |
| 106 | } |
| 107 | |
| 108 | if (state == PM_SUSPEND_MEM) { |
| 109 | local_flush_tlb_all(); |
| 110 | flush_cache_all(); |
| 111 | |
| 112 | /*clear the EMPGC0/1 bits */ |
| 113 | __raw_writel(0, MXC_SRPG_EMPGC0_SRPGCR); |
| 114 | __raw_writel(0, MXC_SRPG_EMPGC1_SRPGCR); |
| 115 | } |
| 116 | cpu_do_idle(); |
| 117 | return 0; |
| 118 | } |
| 119 | |
| 120 | static void mx5_suspend_finish(void) |
| 121 | { |
| 122 | clk_disable(gpc_dvfs_clk); |
| 123 | } |
| 124 | |
| 125 | static int mx5_pm_valid(suspend_state_t state) |
| 126 | { |
| 127 | return (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX); |
| 128 | } |
| 129 | |
| 130 | static const struct platform_suspend_ops mx5_suspend_ops = { |
| 131 | .valid = mx5_pm_valid, |
| 132 | .prepare = mx5_suspend_prepare, |
| 133 | .enter = mx5_suspend_enter, |
| 134 | .finish = mx5_suspend_finish, |
| 135 | }; |
| 136 | |
| 137 | static int __init mx5_pm_init(void) |
| 138 | { |
| 139 | if (!cpu_is_mx51() && !cpu_is_mx53()) |
| 140 | return 0; |
| 141 | |
| 142 | if (gpc_dvfs_clk == NULL) |
| 143 | gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs"); |
| 144 | |
| 145 | if (!IS_ERR(gpc_dvfs_clk)) { |
| 146 | if (cpu_is_mx51()) |
| 147 | suspend_set_ops(&mx5_suspend_ops); |
| 148 | } else |
| 149 | return -EPERM; |
| 150 | |
| 151 | return 0; |
| 152 | } |
| 153 | device_initcall(mx5_pm_init); |