1 /*
2  * Copyright 2011 Freescale Semiconductor, Inc.
3  * Copyright 2011 Linaro Ltd.
4  *
5  * The code contained herein is licensed under the GNU General Public
6  * License. You may obtain a copy of the GNU General Public License
7  * Version 2 or later at the following locations:
8  *
9  * http://www.opensource.org/licenses/gpl-license.html
10  * http://www.gnu.org/copyleft/gpl.html
11  */
12 
13 #include <linux/io.h>
14 #include <linux/irq.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <asm/hardware/gic.h>
19 
20 #define GPC_IMR1		0x008
21 #define GPC_PGC_CPU_PDN		0x2a0
22 
23 #define IMR_NUM			4
24 
25 static void __iomem *gpc_base;
26 static u32 gpc_wake_irqs[IMR_NUM];
27 static u32 gpc_saved_imrs[IMR_NUM];
28 
imx_gpc_pre_suspend(void)29 void imx_gpc_pre_suspend(void)
30 {
31 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
32 	int i;
33 
34 	/* Tell GPC to power off ARM core when suspend */
35 	writel_relaxed(0x1, gpc_base + GPC_PGC_CPU_PDN);
36 
37 	for (i = 0; i < IMR_NUM; i++) {
38 		gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
39 		writel_relaxed(~gpc_wake_irqs[i], reg_imr1 + i * 4);
40 	}
41 }
42 
imx_gpc_post_resume(void)43 void imx_gpc_post_resume(void)
44 {
45 	void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
46 	int i;
47 
48 	/* Keep ARM core powered on for other low-power modes */
49 	writel_relaxed(0x0, gpc_base + GPC_PGC_CPU_PDN);
50 
51 	for (i = 0; i < IMR_NUM; i++)
52 		writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
53 }
54 
imx_gpc_irq_set_wake(struct irq_data * d,unsigned int on)55 static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
56 {
57 	unsigned int idx = d->irq / 32 - 1;
58 	u32 mask;
59 
60 	/* Sanity check for SPI irq */
61 	if (d->irq < 32)
62 		return -EINVAL;
63 
64 	mask = 1 << d->irq % 32;
65 	gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
66 				  gpc_wake_irqs[idx] & ~mask;
67 
68 	return 0;
69 }
70 
imx_gpc_irq_unmask(struct irq_data * d)71 static void imx_gpc_irq_unmask(struct irq_data *d)
72 {
73 	void __iomem *reg;
74 	u32 val;
75 
76 	/* Sanity check for SPI irq */
77 	if (d->irq < 32)
78 		return;
79 
80 	reg = gpc_base + GPC_IMR1 + (d->irq / 32 - 1) * 4;
81 	val = readl_relaxed(reg);
82 	val &= ~(1 << d->irq % 32);
83 	writel_relaxed(val, reg);
84 }
85 
imx_gpc_irq_mask(struct irq_data * d)86 static void imx_gpc_irq_mask(struct irq_data *d)
87 {
88 	void __iomem *reg;
89 	u32 val;
90 
91 	/* Sanity check for SPI irq */
92 	if (d->irq < 32)
93 		return;
94 
95 	reg = gpc_base + GPC_IMR1 + (d->irq / 32 - 1) * 4;
96 	val = readl_relaxed(reg);
97 	val |= 1 << (d->irq % 32);
98 	writel_relaxed(val, reg);
99 }
100 
imx_gpc_init(void)101 void __init imx_gpc_init(void)
102 {
103 	struct device_node *np;
104 
105 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
106 	gpc_base = of_iomap(np, 0);
107 	WARN_ON(!gpc_base);
108 
109 	/* Register GPC as the secondary interrupt controller behind GIC */
110 	gic_arch_extn.irq_mask = imx_gpc_irq_mask;
111 	gic_arch_extn.irq_unmask = imx_gpc_irq_unmask;
112 	gic_arch_extn.irq_set_wake = imx_gpc_irq_set_wake;
113 }
114