drivers/rtc/rtc-imx-sc.c

   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
  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
  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
  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
  83 static 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
  93 static 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
 127 static 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
 135 static 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
 147 static struct notifier_block imx_sc_rtc_alarm_sc_notifier = {
 148         .notifier_call = imx_sc_rtc_alarm_notify,
 149 };
 150
 151 static 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 = devm_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
 178 static const struct of_device_id imx_sc_dt_ids[] = {
 179         { .compatible = "fsl,imx8qxp-sc-rtc", },
 180         {}
 181 };
 182 MODULE_DEVICE_TABLE(of, imx_sc_dt_ids);
 183
 184 static 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 };
 191 module_platform_driver(imx_sc_rtc_driver);
 192
 193 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
 194 MODULE_DESCRIPTION("NXP i.MX System Controller RTC Driver");
 195 MODULE_LICENSE("GPL");