xref: /openbmc/linux/drivers/rtc/rtc-imx-sc.c (revision 7942121b)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2018 NXP.
4  */
5 
6 #include <dt-bindings/firmware/imx/rsrc.h>
7 #include <linux/arm-smccc.h>
8 #include <linux/firmware/imx/sci.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/platform_device.h>
12 #include <linux/rtc.h>
13 
14 #define IMX_SC_TIMER_FUNC_GET_RTC_SEC1970	9
15 #define IMX_SC_TIMER_FUNC_SET_RTC_ALARM		8
16 #define IMX_SC_TIMER_FUNC_SET_RTC_TIME		6
17 
18 #define IMX_SIP_SRTC			0xC2000002
19 #define IMX_SIP_SRTC_SET_TIME		0x0
20 
21 #define SC_IRQ_GROUP_RTC    2
22 #define SC_IRQ_RTC          1
23 
24 static struct imx_sc_ipc *rtc_ipc_handle;
25 static struct rtc_device *imx_sc_rtc;
26 
27 struct imx_sc_msg_timer_get_rtc_time {
28 	struct imx_sc_rpc_msg hdr;
29 	u32 time;
30 } __packed;
31 
32 struct imx_sc_msg_timer_rtc_set_alarm {
33 	struct imx_sc_rpc_msg hdr;
34 	u16 year;
35 	u8 mon;
36 	u8 day;
37 	u8 hour;
38 	u8 min;
39 	u8 sec;
40 } __packed __aligned(4);
41 
imx_sc_rtc_read_time(struct device * dev,struct rtc_time * tm)42 static int imx_sc_rtc_read_time(struct device *dev, struct rtc_time *tm)
43 {
44 	struct imx_sc_msg_timer_get_rtc_time msg;
45 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
46 	int ret;
47 
48 	hdr->ver = IMX_SC_RPC_VERSION;
49 	hdr->svc = IMX_SC_RPC_SVC_TIMER;
50 	hdr->func = IMX_SC_TIMER_FUNC_GET_RTC_SEC1970;
51 	hdr->size = 1;
52 
53 	ret = imx_scu_call_rpc(rtc_ipc_handle, &msg, true);
54 	if (ret) {
55 		dev_err(dev, "read rtc time failed, ret %d\n", ret);
56 		return ret;
57 	}
58 
59 	rtc_time64_to_tm(msg.time, tm);
60 
61 	return 0;
62 }
63 
imx_sc_rtc_set_time(struct device * dev,struct rtc_time * tm)64 static int imx_sc_rtc_set_time(struct device *dev, struct rtc_time *tm)
65 {
66 	struct arm_smccc_res res;
67 
68 	/* pack 2 time parameters into 1 register, 16 bits for each */
69 	arm_smccc_smc(IMX_SIP_SRTC, IMX_SIP_SRTC_SET_TIME,
70 		      ((tm->tm_year + 1900) << 16) | (tm->tm_mon + 1),
71 		      (tm->tm_mday << 16) | tm->tm_hour,
72 		      (tm->tm_min << 16) | tm->tm_sec,
73 		      0, 0, 0, &res);
74 
75 	return res.a0;
76 }
77 
imx_sc_rtc_alarm_irq_enable(struct device * dev,unsigned int enable)78 static int imx_sc_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
79 {
80 	return imx_scu_irq_group_enable(SC_IRQ_GROUP_RTC, SC_IRQ_RTC, enable);
81 }
82 
imx_sc_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alrm)83 static int imx_sc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
84 {
85 	struct imx_sc_msg_timer_rtc_set_alarm msg;
86 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
87 	int ret;
88 	struct rtc_time *alrm_tm = &alrm->time;
89 
90 	hdr->ver = IMX_SC_RPC_VERSION;
91 	hdr->svc = IMX_SC_RPC_SVC_TIMER;
92 	hdr->func = IMX_SC_TIMER_FUNC_SET_RTC_ALARM;
93 	hdr->size = 3;
94 
95 	msg.year = alrm_tm->tm_year + 1900;
96 	msg.mon = alrm_tm->tm_mon + 1;
97 	msg.day = alrm_tm->tm_mday;
98 	msg.hour = alrm_tm->tm_hour;
99 	msg.min = alrm_tm->tm_min;
100 	msg.sec = alrm_tm->tm_sec;
101 
102 	ret = imx_scu_call_rpc(rtc_ipc_handle, &msg, true);
103 	if (ret) {
104 		dev_err(dev, "set rtc alarm failed, ret %d\n", ret);
105 		return ret;
106 	}
107 
108 	ret = imx_sc_rtc_alarm_irq_enable(dev, alrm->enabled);
109 	if (ret) {
110 		dev_err(dev, "enable rtc alarm failed, ret %d\n", ret);
111 		return ret;
112 	}
113 
114 	return 0;
115 }
116 
117 static const struct rtc_class_ops imx_sc_rtc_ops = {
118 	.read_time = imx_sc_rtc_read_time,
119 	.set_time = imx_sc_rtc_set_time,
120 	.set_alarm = imx_sc_rtc_set_alarm,
121 	.alarm_irq_enable = imx_sc_rtc_alarm_irq_enable,
122 };
123 
imx_sc_rtc_alarm_notify(struct notifier_block * nb,unsigned long event,void * group)124 static int imx_sc_rtc_alarm_notify(struct notifier_block *nb,
125 					unsigned long event, void *group)
126 {
127 	/* ignore non-rtc irq */
128 	if (!((event & SC_IRQ_RTC) && (*(u8 *)group == SC_IRQ_GROUP_RTC)))
129 		return 0;
130 
131 	rtc_update_irq(imx_sc_rtc, 1, RTC_IRQF | RTC_AF);
132 
133 	return 0;
134 }
135 
136 static struct notifier_block imx_sc_rtc_alarm_sc_notifier = {
137 	.notifier_call = imx_sc_rtc_alarm_notify,
138 };
139 
imx_sc_rtc_probe(struct platform_device * pdev)140 static int imx_sc_rtc_probe(struct platform_device *pdev)
141 {
142 	int ret;
143 
144 	ret = imx_scu_get_handle(&rtc_ipc_handle);
145 	if (ret)
146 		return ret;
147 
148 	device_init_wakeup(&pdev->dev, true);
149 
150 	imx_sc_rtc = devm_rtc_allocate_device(&pdev->dev);
151 	if (IS_ERR(imx_sc_rtc))
152 		return PTR_ERR(imx_sc_rtc);
153 
154 	imx_sc_rtc->ops = &imx_sc_rtc_ops;
155 	imx_sc_rtc->range_min = 0;
156 	imx_sc_rtc->range_max = U32_MAX;
157 
158 	ret = devm_rtc_register_device(imx_sc_rtc);
159 	if (ret)
160 		return ret;
161 
162 	imx_scu_irq_register_notifier(&imx_sc_rtc_alarm_sc_notifier);
163 
164 	return 0;
165 }
166 
167 static const struct of_device_id imx_sc_dt_ids[] = {
168 	{ .compatible = "fsl,imx8qxp-sc-rtc", },
169 	{}
170 };
171 MODULE_DEVICE_TABLE(of, imx_sc_dt_ids);
172 
173 static struct platform_driver imx_sc_rtc_driver = {
174 	.driver = {
175 		.name	= "imx-sc-rtc",
176 		.of_match_table = imx_sc_dt_ids,
177 	},
178 	.probe		= imx_sc_rtc_probe,
179 };
180 module_platform_driver(imx_sc_rtc_driver);
181 
182 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
183 MODULE_DESCRIPTION("NXP i.MX System Controller RTC Driver");
184 MODULE_LICENSE("GPL");
185