1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright 2008 Openmoko, Inc.
4 // Copyright 2008 Simtec Electronics
5 //      Ben Dooks <ben@simtec.co.uk>
6 //      http://armlinux.simtec.co.uk/
7 //
8 // S3C64XX - Interrupt handling Power Management
9 
10 /*
11  * NOTE: Code in this file is not used when booting with Device Tree support.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/syscore_ops.h>
16 #include <linux/interrupt.h>
17 #include <linux/serial_core.h>
18 #include <linux/serial_s3c.h>
19 #include <linux/irq.h>
20 #include <linux/io.h>
21 #include <linux/of.h>
22 
23 #include "map.h"
24 
25 #include "regs-gpio.h"
26 #include "cpu.h"
27 #include "pm.h"
28 
29 /* We handled all the IRQ types in this code, to save having to make several
30  * small files to handle each different type separately. Having the EINT_GRP
31  * code here shouldn't be as much bloat as the IRQ table space needed when
32  * they are enabled. The added benefit is we ensure that these registers are
33  * in the same state as we suspended.
34  */
35 
36 static struct sleep_save irq_save[] = {
37 	SAVE_ITEM(S3C64XX_PRIORITY),
38 	SAVE_ITEM(S3C64XX_EINT0CON0),
39 	SAVE_ITEM(S3C64XX_EINT0CON1),
40 	SAVE_ITEM(S3C64XX_EINT0FLTCON0),
41 	SAVE_ITEM(S3C64XX_EINT0FLTCON1),
42 	SAVE_ITEM(S3C64XX_EINT0FLTCON2),
43 	SAVE_ITEM(S3C64XX_EINT0FLTCON3),
44 	SAVE_ITEM(S3C64XX_EINT0MASK),
45 };
46 
47 static struct irq_grp_save {
48 	u32	fltcon;
49 	u32	con;
50 	u32	mask;
51 } eint_grp_save[5];
52 
53 #ifndef CONFIG_SERIAL_SAMSUNG_UARTS
54 #define SERIAL_SAMSUNG_UARTS 0
55 #else
56 #define	SERIAL_SAMSUNG_UARTS CONFIG_SERIAL_SAMSUNG_UARTS
57 #endif
58 
59 static u32 irq_uart_mask[SERIAL_SAMSUNG_UARTS];
60 
61 static int s3c64xx_irq_pm_suspend(void)
62 {
63 	struct irq_grp_save *grp = eint_grp_save;
64 	int i;
65 
66 	S3C_PMDBG("%s: suspending IRQs\n", __func__);
67 
68 	s3c_pm_do_save(irq_save, ARRAY_SIZE(irq_save));
69 
70 	for (i = 0; i < SERIAL_SAMSUNG_UARTS; i++)
71 		irq_uart_mask[i] = __raw_readl(S3C_VA_UARTx(i) + S3C64XX_UINTM);
72 
73 	for (i = 0; i < ARRAY_SIZE(eint_grp_save); i++, grp++) {
74 		grp->con = __raw_readl(S3C64XX_EINT12CON + (i * 4));
75 		grp->mask = __raw_readl(S3C64XX_EINT12MASK + (i * 4));
76 		grp->fltcon = __raw_readl(S3C64XX_EINT12FLTCON + (i * 4));
77 	}
78 
79 	return 0;
80 }
81 
82 static void s3c64xx_irq_pm_resume(void)
83 {
84 	struct irq_grp_save *grp = eint_grp_save;
85 	int i;
86 
87 	S3C_PMDBG("%s: resuming IRQs\n", __func__);
88 
89 	s3c_pm_do_restore(irq_save, ARRAY_SIZE(irq_save));
90 
91 	for (i = 0; i < SERIAL_SAMSUNG_UARTS; i++)
92 		__raw_writel(irq_uart_mask[i], S3C_VA_UARTx(i) + S3C64XX_UINTM);
93 
94 	for (i = 0; i < ARRAY_SIZE(eint_grp_save); i++, grp++) {
95 		__raw_writel(grp->con, S3C64XX_EINT12CON + (i * 4));
96 		__raw_writel(grp->mask, S3C64XX_EINT12MASK + (i * 4));
97 		__raw_writel(grp->fltcon, S3C64XX_EINT12FLTCON + (i * 4));
98 	}
99 
100 	S3C_PMDBG("%s: IRQ configuration restored\n", __func__);
101 }
102 
103 static struct syscore_ops s3c64xx_irq_syscore_ops = {
104 	.suspend = s3c64xx_irq_pm_suspend,
105 	.resume	 = s3c64xx_irq_pm_resume,
106 };
107 
108 static __init int s3c64xx_syscore_init(void)
109 {
110 	/* Appropriate drivers (pinctrl, uart) handle this when using DT. */
111 	if (of_have_populated_dt() || !soc_is_s3c64xx())
112 		return 0;
113 
114 	register_syscore_ops(&s3c64xx_irq_syscore_ops);
115 
116 	return 0;
117 }
118 
119 core_initcall(s3c64xx_syscore_init);
120