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
 24static struct imx_sc_ipc *rtc_ipc_handle;
 25static struct rtc_device *imx_sc_rtc;
 26
 27struct imx_sc_msg_timer_get_rtc_time {
 28	struct imx_sc_rpc_msg hdr;
 29	u32 time;
 30} __packed;
 31
 32struct 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
 42static 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
 64static 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
 78static 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
 83static int imx_sc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 84{
 85	/*
 86	 * SCU firmware does NOT provide read alarm API, but .read_alarm
 87	 * callback is required by RTC framework to support alarm function,
 88	 * so just return here.
 89	 */
 90	return 0;
 91}
 92
 93static int imx_sc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 94{
 95	struct imx_sc_msg_timer_rtc_set_alarm msg;
 96	struct imx_sc_rpc_msg *hdr = &msg.hdr;
 97	int ret;
 98	struct rtc_time *alrm_tm = &alrm->time;
 99
100	hdr->ver = IMX_SC_RPC_VERSION;
101	hdr->svc = IMX_SC_RPC_SVC_TIMER;
102	hdr->func = IMX_SC_TIMER_FUNC_SET_RTC_ALARM;
103	hdr->size = 3;
104
105	msg.year = alrm_tm->tm_year + 1900;
106	msg.mon = alrm_tm->tm_mon + 1;
107	msg.day = alrm_tm->tm_mday;
108	msg.hour = alrm_tm->tm_hour;
109	msg.min = alrm_tm->tm_min;
110	msg.sec = alrm_tm->tm_sec;
111
112	ret = imx_scu_call_rpc(rtc_ipc_handle, &msg, true);
113	if (ret) {
114		dev_err(dev, "set rtc alarm failed, ret %d\n", ret);
115		return ret;
116	}
117
118	ret = imx_sc_rtc_alarm_irq_enable(dev, alrm->enabled);
119	if (ret) {
120		dev_err(dev, "enable rtc alarm failed, ret %d\n", ret);
121		return ret;
122	}
123
124	return 0;
125}
126
127static const struct rtc_class_ops imx_sc_rtc_ops = {
128	.read_time = imx_sc_rtc_read_time,
129	.set_time = imx_sc_rtc_set_time,
130	.read_alarm = imx_sc_rtc_read_alarm,
131	.set_alarm = imx_sc_rtc_set_alarm,
132	.alarm_irq_enable = imx_sc_rtc_alarm_irq_enable,
133};
134
135static int imx_sc_rtc_alarm_notify(struct notifier_block *nb,
136					unsigned long event, void *group)
137{
138	/* ignore non-rtc irq */
139	if (!((event & SC_IRQ_RTC) && (*(u8 *)group == SC_IRQ_GROUP_RTC)))
140		return 0;
141
142	rtc_update_irq(imx_sc_rtc, 1, RTC_IRQF | RTC_AF);
143
144	return 0;
145}
146
147static struct notifier_block imx_sc_rtc_alarm_sc_notifier = {
148	.notifier_call = imx_sc_rtc_alarm_notify,
149};
150
151static int imx_sc_rtc_probe(struct platform_device *pdev)
152{
153	int ret;
154
155	ret = imx_scu_get_handle(&rtc_ipc_handle);
156	if (ret)
157		return ret;
158
159	device_init_wakeup(&pdev->dev, true);
160
161	imx_sc_rtc = devm_rtc_allocate_device(&pdev->dev);
162	if (IS_ERR(imx_sc_rtc))
163		return PTR_ERR(imx_sc_rtc);
164
165	imx_sc_rtc->ops = &imx_sc_rtc_ops;
166	imx_sc_rtc->range_min = 0;
167	imx_sc_rtc->range_max = U32_MAX;
168
169	ret = rtc_register_device(imx_sc_rtc);
170	if (ret)
171		return ret;
172
173	imx_scu_irq_register_notifier(&imx_sc_rtc_alarm_sc_notifier);
174
175	return 0;
176}
177
178static const struct of_device_id imx_sc_dt_ids[] = {
179	{ .compatible = "fsl,imx8qxp-sc-rtc", },
180	{}
181};
182MODULE_DEVICE_TABLE(of, imx_sc_dt_ids);
183
184static struct platform_driver imx_sc_rtc_driver = {
185	.driver = {
186		.name	= "imx-sc-rtc",
187		.of_match_table = imx_sc_dt_ids,
188	},
189	.probe		= imx_sc_rtc_probe,
190};
191module_platform_driver(imx_sc_rtc_driver);
192
193MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
194MODULE_DESCRIPTION("NXP i.MX System Controller RTC Driver");
195MODULE_LICENSE("GPL");