xref: /openbmc/linux/arch/sh/boards/mach-hp6xx/pm.c (revision ee7da21a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * hp6x0 Power Management Routines
4  *
5  * Copyright (c) 2006 Andriy Skulysh <askulsyh@gmail.com>
6  */
7 #include <linux/init.h>
8 #include <linux/suspend.h>
9 #include <linux/errno.h>
10 #include <linux/time.h>
11 #include <linux/delay.h>
12 #include <linux/gfp.h>
13 #include <asm/io.h>
14 #include <asm/hd64461.h>
15 #include <asm/bl_bit.h>
16 #include <mach/hp6xx.h>
17 #include <cpu/dac.h>
18 #include <asm/freq.h>
19 #include <asm/watchdog.h>
20 
21 #define INTR_OFFSET	0x600
22 
23 #define STBCR		0xffffff82
24 #define STBCR2		0xffffff88
25 
26 #define STBCR_STBY	0x80
27 #define STBCR_MSTP2	0x04
28 
29 #define MCR		0xffffff68
30 #define RTCNT		0xffffff70
31 
32 #define MCR_RMODE	2
33 #define MCR_RFSH	4
34 
35 extern u8 wakeup_start;
36 extern u8 wakeup_end;
37 
38 static void pm_enter(void)
39 {
40 	u8 stbcr, csr;
41 	u16 frqcr, mcr;
42 	u32 vbr_new, vbr_old;
43 
44 	set_bl_bit();
45 
46 	/* set wdt */
47 	csr = sh_wdt_read_csr();
48 	csr &= ~WTCSR_TME;
49 	csr |= WTCSR_CKS_4096;
50 	sh_wdt_write_csr(csr);
51 	csr = sh_wdt_read_csr();
52 	sh_wdt_write_cnt(0);
53 
54 	/* disable PLL1 */
55 	frqcr = __raw_readw(FRQCR);
56 	frqcr &= ~(FRQCR_PLLEN | FRQCR_PSTBY);
57 	__raw_writew(frqcr, FRQCR);
58 
59 	/* enable standby */
60 	stbcr = __raw_readb(STBCR);
61 	__raw_writeb(stbcr | STBCR_STBY | STBCR_MSTP2, STBCR);
62 
63 	/* set self-refresh */
64 	mcr = __raw_readw(MCR);
65 	__raw_writew(mcr & ~MCR_RFSH, MCR);
66 
67 	/* set interrupt handler */
68 	asm volatile("stc vbr, %0" : "=r" (vbr_old));
69 	vbr_new = get_zeroed_page(GFP_ATOMIC);
70 	udelay(50);
71 	memcpy((void*)(vbr_new + INTR_OFFSET),
72 	       &wakeup_start, &wakeup_end - &wakeup_start);
73 	asm volatile("ldc %0, vbr" : : "r" (vbr_new));
74 
75 	__raw_writew(0, RTCNT);
76 	__raw_writew(mcr | MCR_RFSH | MCR_RMODE, MCR);
77 
78 	cpu_sleep();
79 
80 	asm volatile("ldc %0, vbr" : : "r" (vbr_old));
81 
82 	free_page(vbr_new);
83 
84 	/* enable PLL1 */
85 	frqcr = __raw_readw(FRQCR);
86 	frqcr |= FRQCR_PSTBY;
87 	__raw_writew(frqcr, FRQCR);
88 	udelay(50);
89 	frqcr |= FRQCR_PLLEN;
90 	__raw_writew(frqcr, FRQCR);
91 
92 	__raw_writeb(stbcr, STBCR);
93 
94 	clear_bl_bit();
95 }
96 
97 static int hp6x0_pm_enter(suspend_state_t state)
98 {
99 	u8 stbcr, stbcr2;
100 #ifdef CONFIG_HD64461_ENABLER
101 	u8 scr;
102 	u16 hd64461_stbcr;
103 #endif
104 
105 #ifdef CONFIG_HD64461_ENABLER
106 	outb(0, HD64461_PCC1CSCIER);
107 
108 	scr = inb(HD64461_PCC1SCR);
109 	scr |= HD64461_PCCSCR_VCC1;
110 	outb(scr, HD64461_PCC1SCR);
111 
112 	hd64461_stbcr = inw(HD64461_STBCR);
113 	hd64461_stbcr |= HD64461_STBCR_SPC1ST;
114 	outw(hd64461_stbcr, HD64461_STBCR);
115 #endif
116 
117 	__raw_writeb(0x1f, DACR);
118 
119 	stbcr = __raw_readb(STBCR);
120 	__raw_writeb(0x01, STBCR);
121 
122 	stbcr2 = __raw_readb(STBCR2);
123 	__raw_writeb(0x7f , STBCR2);
124 
125 	outw(0xf07f, HD64461_SCPUCR);
126 
127 	pm_enter();
128 
129 	outw(0, HD64461_SCPUCR);
130 	__raw_writeb(stbcr, STBCR);
131 	__raw_writeb(stbcr2, STBCR2);
132 
133 #ifdef CONFIG_HD64461_ENABLER
134 	hd64461_stbcr = inw(HD64461_STBCR);
135 	hd64461_stbcr &= ~HD64461_STBCR_SPC1ST;
136 	outw(hd64461_stbcr, HD64461_STBCR);
137 
138 	outb(0x4c, HD64461_PCC1CSCIER);
139 	outb(0x00, HD64461_PCC1CSCR);
140 #endif
141 
142 	return 0;
143 }
144 
145 static const struct platform_suspend_ops hp6x0_pm_ops = {
146 	.enter		= hp6x0_pm_enter,
147 	.valid		= suspend_valid_only_mem,
148 };
149 
150 static int __init hp6x0_pm_init(void)
151 {
152 	suspend_set_ops(&hp6x0_pm_ops);
153 	return 0;
154 }
155 
156 late_initcall(hp6x0_pm_init);
157