xref: /linux/arch/arm/mach-imx/pm-imx5.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 <linux/export.h>
16 #include <asm/cacheflush.h>
17 #include <asm/system_misc.h>
18 #include <asm/tlbflush.h>
19 
20 #include "common.h"
21 #include "cpuidle.h"
22 #include "hardware.h"
23 
24 #define MXC_CCM_CLPCR			0x54
25 #define MXC_CCM_CLPCR_LPM_OFFSET	0
26 #define MXC_CCM_CLPCR_LPM_MASK		0x3
27 #define MXC_CCM_CLPCR_STBY_COUNT_OFFSET	9
28 #define MXC_CCM_CLPCR_VSTBY		(0x1 << 8)
29 #define MXC_CCM_CLPCR_SBYOS		(0x1 << 6)
30 
31 #define MXC_CORTEXA8_PLAT_LPC		0xc
32 #define MXC_CORTEXA8_PLAT_LPC_DSM	(1 << 0)
33 #define MXC_CORTEXA8_PLAT_LPC_DBG_DSM	(1 << 1)
34 
35 #define MXC_SRPG_NEON_SRPGCR		0x280
36 #define MXC_SRPG_ARM_SRPGCR		0x2a0
37 #define MXC_SRPG_EMPGC0_SRPGCR		0x2c0
38 #define MXC_SRPG_EMPGC1_SRPGCR		0x2d0
39 
40 #define MXC_SRPGCR_PCR			1
41 
42 /*
43  * The WAIT_UNCLOCKED_POWER_OFF state only requires <= 500ns to exit.
44  * This is also the lowest power state possible without affecting
45  * non-cpu parts of the system.  For these reasons, imx5 should default
46  * to always using this state for cpu idling.  The PM_SUSPEND_STANDBY also
47  * uses this state and needs to take no action when registers remain confgiured
48  * for this state.
49  */
50 #define IMX5_DEFAULT_CPU_IDLE_STATE WAIT_UNCLOCKED_POWER_OFF
51 
52 struct imx5_pm_data {
53 	phys_addr_t cortex_addr;
54 	phys_addr_t gpc_addr;
55 };
56 
57 static const struct imx5_pm_data imx51_pm_data __initconst = {
58 	.cortex_addr = 0x83fa0000,
59 	.gpc_addr = 0x73fd8000,
60 };
61 
62 static const struct imx5_pm_data imx53_pm_data __initconst = {
63 	.cortex_addr = 0x63fa0000,
64 	.gpc_addr = 0x53fd8000,
65 };
66 
67 static void __iomem *ccm_base;
68 static void __iomem *cortex_base;
69 static void __iomem *gpc_base;
70 
71 void __init imx5_pm_set_ccm_base(void __iomem *base)
72 {
73 	ccm_base = base;
74 }
75 
76 /*
77  * set cpu low power mode before WFI instruction. This function is called
78  * mx5 because it can be used for mx51, and mx53.
79  */
80 static void mx5_cpu_lp_set(enum mxc_cpu_pwr_mode mode)
81 {
82 	u32 plat_lpc, arm_srpgcr, ccm_clpcr;
83 	u32 empgc0, empgc1;
84 	int stop_mode = 0;
85 
86 	/* always allow platform to issue a deep sleep mode request */
87 	plat_lpc = __raw_readl(cortex_base + MXC_CORTEXA8_PLAT_LPC) &
88 	    ~(MXC_CORTEXA8_PLAT_LPC_DSM);
89 	ccm_clpcr = __raw_readl(ccm_base + MXC_CCM_CLPCR) &
90 		    ~(MXC_CCM_CLPCR_LPM_MASK);
91 	arm_srpgcr = __raw_readl(gpc_base + MXC_SRPG_ARM_SRPGCR) &
92 		     ~(MXC_SRPGCR_PCR);
93 	empgc0 = __raw_readl(gpc_base + MXC_SRPG_EMPGC0_SRPGCR) &
94 		 ~(MXC_SRPGCR_PCR);
95 	empgc1 = __raw_readl(gpc_base + MXC_SRPG_EMPGC1_SRPGCR) &
96 		 ~(MXC_SRPGCR_PCR);
97 
98 	switch (mode) {
99 	case WAIT_CLOCKED:
100 		break;
101 	case WAIT_UNCLOCKED:
102 		ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET;
103 		break;
104 	case WAIT_UNCLOCKED_POWER_OFF:
105 	case STOP_POWER_OFF:
106 		plat_lpc |= MXC_CORTEXA8_PLAT_LPC_DSM
107 			    | MXC_CORTEXA8_PLAT_LPC_DBG_DSM;
108 		if (mode == WAIT_UNCLOCKED_POWER_OFF) {
109 			ccm_clpcr |= 0x1 << MXC_CCM_CLPCR_LPM_OFFSET;
110 			ccm_clpcr &= ~MXC_CCM_CLPCR_VSTBY;
111 			ccm_clpcr &= ~MXC_CCM_CLPCR_SBYOS;
112 			stop_mode = 0;
113 		} else {
114 			ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET;
115 			ccm_clpcr |= 0x3 << MXC_CCM_CLPCR_STBY_COUNT_OFFSET;
116 			ccm_clpcr |= MXC_CCM_CLPCR_VSTBY;
117 			ccm_clpcr |= MXC_CCM_CLPCR_SBYOS;
118 			stop_mode = 1;
119 		}
120 		arm_srpgcr |= MXC_SRPGCR_PCR;
121 		break;
122 	case STOP_POWER_ON:
123 		ccm_clpcr |= 0x2 << MXC_CCM_CLPCR_LPM_OFFSET;
124 		break;
125 	default:
126 		printk(KERN_WARNING "UNKNOWN cpu power mode: %d\n", mode);
127 		return;
128 	}
129 
130 	__raw_writel(plat_lpc, cortex_base + MXC_CORTEXA8_PLAT_LPC);
131 	__raw_writel(ccm_clpcr, ccm_base + MXC_CCM_CLPCR);
132 	__raw_writel(arm_srpgcr, gpc_base + MXC_SRPG_ARM_SRPGCR);
133 	__raw_writel(arm_srpgcr, gpc_base + MXC_SRPG_NEON_SRPGCR);
134 
135 	if (stop_mode) {
136 		empgc0 |= MXC_SRPGCR_PCR;
137 		empgc1 |= MXC_SRPGCR_PCR;
138 
139 		__raw_writel(empgc0, gpc_base + MXC_SRPG_EMPGC0_SRPGCR);
140 		__raw_writel(empgc1, gpc_base + MXC_SRPG_EMPGC1_SRPGCR);
141 	}
142 }
143 
144 static int mx5_suspend_enter(suspend_state_t state)
145 {
146 	switch (state) {
147 	case PM_SUSPEND_MEM:
148 		mx5_cpu_lp_set(STOP_POWER_OFF);
149 		break;
150 	case PM_SUSPEND_STANDBY:
151 		/* DEFAULT_IDLE_STATE already configured */
152 		break;
153 	default:
154 		return -EINVAL;
155 	}
156 
157 	if (state == PM_SUSPEND_MEM) {
158 		local_flush_tlb_all();
159 		flush_cache_all();
160 
161 		/*clear the EMPGC0/1 bits */
162 		__raw_writel(0, gpc_base + MXC_SRPG_EMPGC0_SRPGCR);
163 		__raw_writel(0, gpc_base + MXC_SRPG_EMPGC1_SRPGCR);
164 	}
165 	cpu_do_idle();
166 
167 	/* return registers to default idle state */
168 	mx5_cpu_lp_set(IMX5_DEFAULT_CPU_IDLE_STATE);
169 	return 0;
170 }
171 
172 static int mx5_pm_valid(suspend_state_t state)
173 {
174 	return (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX);
175 }
176 
177 static const struct platform_suspend_ops mx5_suspend_ops = {
178 	.valid = mx5_pm_valid,
179 	.enter = mx5_suspend_enter,
180 };
181 
182 static inline int imx5_cpu_do_idle(void)
183 {
184 	int ret = tzic_enable_wake();
185 
186 	if (likely(!ret))
187 		cpu_do_idle();
188 
189 	return ret;
190 }
191 
192 static void imx5_pm_idle(void)
193 {
194 	imx5_cpu_do_idle();
195 }
196 
197 static int __init imx5_pm_common_init(const struct imx5_pm_data *data)
198 {
199 	int ret;
200 	struct clk *gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs");
201 
202 	if (IS_ERR(gpc_dvfs_clk))
203 		return PTR_ERR(gpc_dvfs_clk);
204 
205 	ret = clk_prepare_enable(gpc_dvfs_clk);
206 	if (ret)
207 		return ret;
208 
209 	arm_pm_idle = imx5_pm_idle;
210 
211 	cortex_base = ioremap(data->cortex_addr, SZ_16K);
212 	gpc_base = ioremap(data->gpc_addr, SZ_16K);
213 	WARN_ON(!ccm_base || !cortex_base || !gpc_base);
214 
215 	/* Set the registers to the default cpu idle state. */
216 	mx5_cpu_lp_set(IMX5_DEFAULT_CPU_IDLE_STATE);
217 
218 	ret = imx5_cpuidle_init();
219 	if (ret)
220 		pr_warn("%s: cpuidle init failed %d\n", __func__, ret);
221 
222 	suspend_set_ops(&mx5_suspend_ops);
223 
224 	return 0;
225 }
226 
227 void __init imx51_pm_init(void)
228 {
229 	imx5_pm_common_init(&imx51_pm_data);
230 }
231 
232 void __init imx53_pm_init(void)
233 {
234 	imx5_pm_common_init(&imx53_pm_data);
235 }
236