xref: /linux/arch/powerpc/platforms/52xx/mpc52xx_pm.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/init.h>
3 #include <linux/suspend.h>
4 #include <linux/io.h>
5 #include <linux/of_address.h>
6 
7 #include <asm/time.h>
8 #include <asm/cacheflush.h>
9 #include <asm/mpc52xx.h>
10 
11 /* these are defined in mpc52xx_sleep.S, and only used here */
12 extern void mpc52xx_deep_sleep(void __iomem *sram, void __iomem *sdram_regs,
13 		struct mpc52xx_cdm __iomem *, struct mpc52xx_intr __iomem*);
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 __iomem *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(void)
61 {
62 	struct device_node *np;
63 	static const struct of_device_id immr_ids[] = {
64 		{ .compatible = "fsl,mpc5200-immr", },
65 		{ .compatible = "fsl,mpc5200b-immr", },
66 		{ .type = "soc", .compatible = "mpc5200", }, /* lite5200 */
67 		{ .type = "builtin", .compatible = "mpc5200", }, /* efika */
68 		{}
69 	};
70 	struct resource res;
71 
72 	/* map the whole register space */
73 	np = of_find_matching_node(NULL, immr_ids);
74 
75 	if (of_address_to_resource(np, 0, &res)) {
76 		pr_err("mpc52xx_pm_prepare(): could not get IMMR address\n");
77 		of_node_put(np);
78 		return -ENOSYS;
79 	}
80 
81 	mbar = ioremap(res.start, 0xc000); /* we should map whole region including SRAM */
82 
83 	of_node_put(np);
84 	if (!mbar) {
85 		pr_err("mpc52xx_pm_prepare(): could not map registers\n");
86 		return -ENOSYS;
87 	}
88 	/* these offsets are from mpc5200 users manual */
89 	sdram	= mbar + 0x100;
90 	cdm	= mbar + 0x200;
91 	intr	= mbar + 0x500;
92 	gpiow	= mbar + 0xc00;
93 	sram	= mbar + 0x8000;	/* Those will be handled by the */
94 	sram_size = 0x4000;		/* bestcomm driver soon */
95 
96 	/* call board suspend code, if applicable */
97 	if (mpc52xx_suspend.board_suspend_prepare)
98 		mpc52xx_suspend.board_suspend_prepare(mbar);
99 	else {
100 		printk(KERN_ALERT "%s: %i don't know how to wake up the board\n",
101 				__func__, __LINE__);
102 		goto out_unmap;
103 	}
104 
105 	return 0;
106 
107  out_unmap:
108 	iounmap(mbar);
109 	return -ENOSYS;
110 }
111 
112 
113 char saved_sram[0x4000];
114 
115 int mpc52xx_pm_enter(suspend_state_t state)
116 {
117 	u32 clk_enables;
118 	u32 msr, hid0;
119 	u32 intr_main_mask;
120 	void __iomem * irq_0x500 = (void __iomem *)CONFIG_KERNEL_START + 0x500;
121 	unsigned long irq_0x500_stop = (unsigned long)irq_0x500 + mpc52xx_ds_cached_size;
122 	char saved_0x500[0x600-0x500];
123 
124 	if (WARN_ON(mpc52xx_ds_cached_size > sizeof(saved_0x500)))
125 		return -ENOMEM;
126 
127 	/* disable all interrupts in PIC */
128 	intr_main_mask = in_be32(&intr->main_mask);
129 	out_be32(&intr->main_mask, intr_main_mask | 0x1ffff);
130 
131 	/* don't let DEC expire any time soon */
132 	mtspr(SPRN_DEC, 0x7fffffff);
133 
134 	/* save SRAM */
135 	memcpy(saved_sram, sram, sram_size);
136 
137 	/* copy low level suspend code to sram */
138 	memcpy(sram, mpc52xx_ds_sram, mpc52xx_ds_sram_size);
139 
140 	out_8(&cdm->ccs_sleep_enable, 1);
141 	out_8(&cdm->osc_sleep_enable, 1);
142 	out_8(&cdm->ccs_qreq_test, 1);
143 
144 	/* disable all but SDRAM and bestcomm (SRAM) clocks */
145 	clk_enables = in_be32(&cdm->clk_enables);
146 	out_be32(&cdm->clk_enables, clk_enables & 0x00088000);
147 
148 	/* disable power management */
149 	msr = mfmsr();
150 	mtmsr(msr & ~MSR_POW);
151 
152 	/* enable sleep mode, disable others */
153 	hid0 = mfspr(SPRN_HID0);
154 	mtspr(SPRN_HID0, (hid0 & ~(HID0_DOZE | HID0_NAP | HID0_DPM)) | HID0_SLEEP);
155 
156 	/* save original, copy our irq handler, flush from dcache and invalidate icache */
157 	memcpy(saved_0x500, irq_0x500, mpc52xx_ds_cached_size);
158 	memcpy(irq_0x500, mpc52xx_ds_cached, mpc52xx_ds_cached_size);
159 	flush_icache_range((unsigned long)irq_0x500, irq_0x500_stop);
160 
161 	/* call low-level sleep code */
162 	mpc52xx_deep_sleep(sram, sdram, cdm, intr);
163 
164 	/* restore original irq handler */
165 	memcpy(irq_0x500, saved_0x500, mpc52xx_ds_cached_size);
166 	flush_icache_range((unsigned long)irq_0x500, irq_0x500_stop);
167 
168 	/* restore old power mode */
169 	mtmsr(msr & ~MSR_POW);
170 	mtspr(SPRN_HID0, hid0);
171 	mtmsr(msr);
172 
173 	out_be32(&cdm->clk_enables, clk_enables);
174 	out_8(&cdm->ccs_sleep_enable, 0);
175 	out_8(&cdm->osc_sleep_enable, 0);
176 
177 	/* restore SRAM */
178 	memcpy(sram, saved_sram, sram_size);
179 
180 	/* reenable interrupts in PIC */
181 	out_be32(&intr->main_mask, intr_main_mask);
182 
183 	return 0;
184 }
185 
186 void mpc52xx_pm_finish(void)
187 {
188 	/* call board resume code */
189 	if (mpc52xx_suspend.board_resume_finish)
190 		mpc52xx_suspend.board_resume_finish(mbar);
191 
192 	iounmap(mbar);
193 }
194 
195 static const struct platform_suspend_ops mpc52xx_pm_ops = {
196 	.valid		= mpc52xx_pm_valid,
197 	.prepare	= mpc52xx_pm_prepare,
198 	.enter		= mpc52xx_pm_enter,
199 	.finish		= mpc52xx_pm_finish,
200 };
201 
202 int __init mpc52xx_pm_init(void)
203 {
204 	suspend_set_ops(&mpc52xx_pm_ops);
205 	return 0;
206 }
207