1 #include <linux/init.h>
2 #include <linux/pm.h>
3 #include <linux/io.h>
4 #include <asm/time.h>
5 #include <asm/cacheflush.h>
6 #include <asm/mpc52xx.h>
7 
8 #include "mpc52xx_pic.h"
9 
10 
11 /* these are defined in mpc52xx_sleep.S, and only used here */
12 extern void mpc52xx_deep_sleep(void *sram, void *sdram_regs,
13 		struct mpc52xx_cdm *, struct mpc52xx_intr *);
14 extern void mpc52xx_ds_sram(void);
15 extern const long mpc52xx_ds_sram_size;
16 extern void mpc52xx_ds_cached(void);
17 extern const long mpc52xx_ds_cached_size;
18 
19 static void __iomem *mbar;
20 static void __iomem *sdram;
21 static struct mpc52xx_cdm __iomem *cdm;
22 static struct mpc52xx_intr __iomem *intr;
23 static struct mpc52xx_gpio_wkup __iomem *gpiow;
24 static void *sram;
25 static int sram_size;
26 
27 struct mpc52xx_suspend mpc52xx_suspend;
28 
29 static int mpc52xx_pm_valid(suspend_state_t state)
30 {
31 	switch (state) {
32 	case PM_SUSPEND_STANDBY:
33 		return 1;
34 	default:
35 		return 0;
36 	}
37 }
38 
39 int mpc52xx_set_wakeup_gpio(u8 pin, u8 level)
40 {
41 	u16 tmp;
42 
43 	/* enable gpio */
44 	out_8(&gpiow->wkup_gpioe, in_8(&gpiow->wkup_gpioe) | (1 << pin));
45 	/* set as input */
46 	out_8(&gpiow->wkup_ddr, in_8(&gpiow->wkup_ddr) & ~(1 << pin));
47 	/* enable deep sleep interrupt */
48 	out_8(&gpiow->wkup_inten, in_8(&gpiow->wkup_inten) | (1 << pin));
49 	/* low/high level creates wakeup interrupt */
50 	tmp = in_be16(&gpiow->wkup_itype);
51 	tmp &= ~(0x3 << (pin * 2));
52 	tmp |= (!level + 1) << (pin * 2);
53 	out_be16(&gpiow->wkup_itype, tmp);
54 	/* master enable */
55 	out_8(&gpiow->wkup_maste, 1);
56 
57 	return 0;
58 }
59 
60 int mpc52xx_pm_prepare(suspend_state_t state)
61 {
62 	if (state != PM_SUSPEND_STANDBY)
63 		return -EINVAL;
64 
65 	/* map the whole register space */
66 	mbar = mpc52xx_find_and_map("mpc5200");
67 	if (!mbar) {
68 		printk(KERN_ERR "%s:%i Error mapping registers\n", __func__, __LINE__);
69 		return -ENOSYS;
70 	}
71 	/* these offsets are from mpc5200 users manual */
72 	sdram	= mbar + 0x100;
73 	cdm	= mbar + 0x200;
74 	intr	= mbar + 0x500;
75 	gpiow	= mbar + 0xc00;
76 	sram	= mbar + 0x8000;	/* Those will be handled by the */
77 	sram_size = 0x4000;		/* bestcomm driver soon */
78 
79 	/* call board suspend code, if applicable */
80 	if (mpc52xx_suspend.board_suspend_prepare)
81 		mpc52xx_suspend.board_suspend_prepare(mbar);
82 	else {
83 		printk(KERN_ALERT "%s: %i don't know how to wake up the board\n",
84 				__func__, __LINE__);
85 		goto out_unmap;
86 	}
87 
88 	return 0;
89 
90  out_unmap:
91 	iounmap(mbar);
92 	return -ENOSYS;
93 }
94 
95 
96 char saved_sram[0x4000];
97 
98 int mpc52xx_pm_enter(suspend_state_t state)
99 {
100 	u32 clk_enables;
101 	u32 msr, hid0;
102 	u32 intr_main_mask;
103 	void __iomem * irq_0x500 = (void *)CONFIG_KERNEL_START + 0x500;
104 	unsigned long irq_0x500_stop = (unsigned long)irq_0x500 + mpc52xx_ds_cached_size;
105 	char saved_0x500[mpc52xx_ds_cached_size];
106 
107 	/* disable all interrupts in PIC */
108 	intr_main_mask = in_be32(&intr->main_mask);
109 	out_be32(&intr->main_mask, intr_main_mask | 0x1ffff);
110 
111 	/* don't let DEC expire any time soon */
112 	mtspr(SPRN_DEC, 0x7fffffff);
113 
114 	/* save SRAM */
115 	memcpy(saved_sram, sram, sram_size);
116 
117 	/* copy low level suspend code to sram */
118 	memcpy(sram, mpc52xx_ds_sram, mpc52xx_ds_sram_size);
119 
120 	out_8(&cdm->ccs_sleep_enable, 1);
121 	out_8(&cdm->osc_sleep_enable, 1);
122 	out_8(&cdm->ccs_qreq_test, 1);
123 
124 	/* disable all but SDRAM and bestcomm (SRAM) clocks */
125 	clk_enables = in_be32(&cdm->clk_enables);
126 	out_be32(&cdm->clk_enables, clk_enables & 0x00088000);
127 
128 	/* disable power management */
129 	msr = mfmsr();
130 	mtmsr(msr & ~MSR_POW);
131 
132 	/* enable sleep mode, disable others */
133 	hid0 = mfspr(SPRN_HID0);
134 	mtspr(SPRN_HID0, (hid0 & ~(HID0_DOZE | HID0_NAP | HID0_DPM)) | HID0_SLEEP);
135 
136 	/* save original, copy our irq handler, flush from dcache and invalidate icache */
137 	memcpy(saved_0x500, irq_0x500, mpc52xx_ds_cached_size);
138 	memcpy(irq_0x500, mpc52xx_ds_cached, mpc52xx_ds_cached_size);
139 	flush_icache_range((unsigned long)irq_0x500, irq_0x500_stop);
140 
141 	/* call low-level sleep code */
142 	mpc52xx_deep_sleep(sram, sdram, cdm, intr);
143 
144 	/* restore original irq handler */
145 	memcpy(irq_0x500, saved_0x500, mpc52xx_ds_cached_size);
146 	flush_icache_range((unsigned long)irq_0x500, irq_0x500_stop);
147 
148 	/* restore old power mode */
149 	mtmsr(msr & ~MSR_POW);
150 	mtspr(SPRN_HID0, hid0);
151 	mtmsr(msr);
152 
153 	out_be32(&cdm->clk_enables, clk_enables);
154 	out_8(&cdm->ccs_sleep_enable, 0);
155 	out_8(&cdm->osc_sleep_enable, 0);
156 
157 	/* restore SRAM */
158 	memcpy(sram, saved_sram, sram_size);
159 
160 	/* restart jiffies */
161 	wakeup_decrementer();
162 
163 	/* reenable interrupts in PIC */
164 	out_be32(&intr->main_mask, intr_main_mask);
165 
166 	return 0;
167 }
168 
169 int mpc52xx_pm_finish(suspend_state_t state)
170 {
171 	/* call board resume code */
172 	if (mpc52xx_suspend.board_resume_finish)
173 		mpc52xx_suspend.board_resume_finish(mbar);
174 
175 	iounmap(mbar);
176 
177 	return 0;
178 }
179 
180 static struct pm_ops mpc52xx_pm_ops = {
181 	.valid		= mpc52xx_pm_valid,
182 	.prepare	= mpc52xx_pm_prepare,
183 	.enter		= mpc52xx_pm_enter,
184 	.finish		= mpc52xx_pm_finish,
185 };
186 
187 int __init mpc52xx_pm_init(void)
188 {
189 	pm_set_ops(&mpc52xx_pm_ops);
190 	return 0;
191 }
192