xref: /linux/arch/powerpc/platforms/52xx/mpc52xx_pm.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 #include <linux/init.h>
2 #include <linux/suspend.h>
3 #include <linux/io.h>
4 #include <asm/time.h>
5 #include <asm/cacheflush.h>
6 #include <asm/mpc52xx.h>
7 
8 /* these are defined in mpc52xx_sleep.S, and only used here */
9 extern void mpc52xx_deep_sleep(void __iomem *sram, void __iomem *sdram_regs,
10 		struct mpc52xx_cdm __iomem *, struct mpc52xx_intr __iomem*);
11 extern void mpc52xx_ds_sram(void);
12 extern const long mpc52xx_ds_sram_size;
13 extern void mpc52xx_ds_cached(void);
14 extern const long mpc52xx_ds_cached_size;
15 
16 static void __iomem *mbar;
17 static void __iomem *sdram;
18 static struct mpc52xx_cdm __iomem *cdm;
19 static struct mpc52xx_intr __iomem *intr;
20 static struct mpc52xx_gpio_wkup __iomem *gpiow;
21 static void __iomem *sram;
22 static int sram_size;
23 
24 struct mpc52xx_suspend mpc52xx_suspend;
25 
26 static int mpc52xx_pm_valid(suspend_state_t state)
27 {
28 	switch (state) {
29 	case PM_SUSPEND_STANDBY:
30 		return 1;
31 	default:
32 		return 0;
33 	}
34 }
35 
36 int mpc52xx_set_wakeup_gpio(u8 pin, u8 level)
37 {
38 	u16 tmp;
39 
40 	/* enable gpio */
41 	out_8(&gpiow->wkup_gpioe, in_8(&gpiow->wkup_gpioe) | (1 << pin));
42 	/* set as input */
43 	out_8(&gpiow->wkup_ddr, in_8(&gpiow->wkup_ddr) & ~(1 << pin));
44 	/* enable deep sleep interrupt */
45 	out_8(&gpiow->wkup_inten, in_8(&gpiow->wkup_inten) | (1 << pin));
46 	/* low/high level creates wakeup interrupt */
47 	tmp = in_be16(&gpiow->wkup_itype);
48 	tmp &= ~(0x3 << (pin * 2));
49 	tmp |= (!level + 1) << (pin * 2);
50 	out_be16(&gpiow->wkup_itype, tmp);
51 	/* master enable */
52 	out_8(&gpiow->wkup_maste, 1);
53 
54 	return 0;
55 }
56 
57 int mpc52xx_pm_prepare(void)
58 {
59 	struct device_node *np;
60 	const struct of_device_id immr_ids[] = {
61 		{ .compatible = "fsl,mpc5200-immr", },
62 		{ .compatible = "fsl,mpc5200b-immr", },
63 		{ .type = "soc", .compatible = "mpc5200", }, /* lite5200 */
64 		{ .type = "builtin", .compatible = "mpc5200", }, /* efika */
65 		{}
66 	};
67 	struct resource res;
68 
69 	/* map the whole register space */
70 	np = of_find_matching_node(NULL, immr_ids);
71 
72 	if (of_address_to_resource(np, 0, &res)) {
73 		pr_err("mpc52xx_pm_prepare(): could not get IMMR address\n");
74 		of_node_put(np);
75 		return -ENOSYS;
76 	}
77 
78 	mbar = ioremap(res.start, 0xc000); /* we should map whole region including SRAM */
79 
80 	of_node_put(np);
81 	if (!mbar) {
82 		pr_err("mpc52xx_pm_prepare(): could not map registers\n");
83 		return -ENOSYS;
84 	}
85 	/* these offsets are from mpc5200 users manual */
86 	sdram	= mbar + 0x100;
87 	cdm	= mbar + 0x200;
88 	intr	= mbar + 0x500;
89 	gpiow	= mbar + 0xc00;
90 	sram	= mbar + 0x8000;	/* Those will be handled by the */
91 	sram_size = 0x4000;		/* bestcomm driver soon */
92 
93 	/* call board suspend code, if applicable */
94 	if (mpc52xx_suspend.board_suspend_prepare)
95 		mpc52xx_suspend.board_suspend_prepare(mbar);
96 	else {
97 		printk(KERN_ALERT "%s: %i don't know how to wake up the board\n",
98 				__func__, __LINE__);
99 		goto out_unmap;
100 	}
101 
102 	return 0;
103 
104  out_unmap:
105 	iounmap(mbar);
106 	return -ENOSYS;
107 }
108 
109 
110 char saved_sram[0x4000];
111 
112 int mpc52xx_pm_enter(suspend_state_t state)
113 {
114 	u32 clk_enables;
115 	u32 msr, hid0;
116 	u32 intr_main_mask;
117 	void __iomem * irq_0x500 = (void __iomem *)CONFIG_KERNEL_START + 0x500;
118 	unsigned long irq_0x500_stop = (unsigned long)irq_0x500 + mpc52xx_ds_cached_size;
119 	char saved_0x500[mpc52xx_ds_cached_size];
120 
121 	/* disable all interrupts in PIC */
122 	intr_main_mask = in_be32(&intr->main_mask);
123 	out_be32(&intr->main_mask, intr_main_mask | 0x1ffff);
124 
125 	/* don't let DEC expire any time soon */
126 	mtspr(SPRN_DEC, 0x7fffffff);
127 
128 	/* save SRAM */
129 	memcpy(saved_sram, sram, sram_size);
130 
131 	/* copy low level suspend code to sram */
132 	memcpy(sram, mpc52xx_ds_sram, mpc52xx_ds_sram_size);
133 
134 	out_8(&cdm->ccs_sleep_enable, 1);
135 	out_8(&cdm->osc_sleep_enable, 1);
136 	out_8(&cdm->ccs_qreq_test, 1);
137 
138 	/* disable all but SDRAM and bestcomm (SRAM) clocks */
139 	clk_enables = in_be32(&cdm->clk_enables);
140 	out_be32(&cdm->clk_enables, clk_enables & 0x00088000);
141 
142 	/* disable power management */
143 	msr = mfmsr();
144 	mtmsr(msr & ~MSR_POW);
145 
146 	/* enable sleep mode, disable others */
147 	hid0 = mfspr(SPRN_HID0);
148 	mtspr(SPRN_HID0, (hid0 & ~(HID0_DOZE | HID0_NAP | HID0_DPM)) | HID0_SLEEP);
149 
150 	/* save original, copy our irq handler, flush from dcache and invalidate icache */
151 	memcpy(saved_0x500, irq_0x500, mpc52xx_ds_cached_size);
152 	memcpy(irq_0x500, mpc52xx_ds_cached, mpc52xx_ds_cached_size);
153 	flush_icache_range((unsigned long)irq_0x500, irq_0x500_stop);
154 
155 	/* call low-level sleep code */
156 	mpc52xx_deep_sleep(sram, sdram, cdm, intr);
157 
158 	/* restore original irq handler */
159 	memcpy(irq_0x500, saved_0x500, mpc52xx_ds_cached_size);
160 	flush_icache_range((unsigned long)irq_0x500, irq_0x500_stop);
161 
162 	/* restore old power mode */
163 	mtmsr(msr & ~MSR_POW);
164 	mtspr(SPRN_HID0, hid0);
165 	mtmsr(msr);
166 
167 	out_be32(&cdm->clk_enables, clk_enables);
168 	out_8(&cdm->ccs_sleep_enable, 0);
169 	out_8(&cdm->osc_sleep_enable, 0);
170 
171 	/* restore SRAM */
172 	memcpy(sram, saved_sram, sram_size);
173 
174 	/* reenable interrupts in PIC */
175 	out_be32(&intr->main_mask, intr_main_mask);
176 
177 	return 0;
178 }
179 
180 void mpc52xx_pm_finish(void)
181 {
182 	/* call board resume code */
183 	if (mpc52xx_suspend.board_resume_finish)
184 		mpc52xx_suspend.board_resume_finish(mbar);
185 
186 	iounmap(mbar);
187 }
188 
189 static const struct platform_suspend_ops mpc52xx_pm_ops = {
190 	.valid		= mpc52xx_pm_valid,
191 	.prepare	= mpc52xx_pm_prepare,
192 	.enter		= mpc52xx_pm_enter,
193 	.finish		= mpc52xx_pm_finish,
194 };
195 
196 int __init mpc52xx_pm_init(void)
197 {
198 	suspend_set_ops(&mpc52xx_pm_ops);
199 	return 0;
200 }
201