Commit e01b5781 authored by Anson Huang's avatar Anson Huang Committed by Alexandre Belloni
Browse files

rtc: add i.MX system controller RTC support 



i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
inside, the system controller is in charge of controlling power,
clock and secure rtc etc..

This patch adds i.MX system controller RTC driver support,
Linux kernel has to communicate with system controller via MU
(message unit) IPC to set/get RTC time and other alarm functions,
since the RTC set time needs to be done in secure EL3 mode (required
by system controller firmware) and alarm functions needs to be done
with general MU IRQ handle, these depend on other components which
are NOT ready, so this patch ONLY enables the RTC time read.

Signed-off-by: default avatarAnson Huang <Anson.Huang@nxp.com>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 2ea44ca1

drivers/rtc/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -1677,6 +1677,13 @@ config RTC_DRV_SNVS 
	   This driver can also be built as a module, if so, the module

	   will be called "rtc-snvs".



config RTC_DRV_IMX_SC

	depends on IMX_SCU

	tristate "NXP i.MX System Controller RTC support"

	help

	   If you say yes here you get support for the NXP i.MX System

	   Controller RTC module.



config RTC_DRV_SIRFSOC

	tristate "SiRFSOC RTC"

	depends on ARCH_SIRF

drivers/rtc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -75,6 +75,7 @@ obj-$(CONFIG_RTC_DRV_GOLDFISH) += rtc-goldfish.o 
obj-$(CONFIG_RTC_DRV_HID_SENSOR_TIME) += rtc-hid-sensor-time.o

obj-$(CONFIG_RTC_DRV_HYM8563)	+= rtc-hym8563.o

obj-$(CONFIG_RTC_DRV_IMXDI)	+= rtc-imxdi.o

obj-$(CONFIG_RTC_DRV_IMX_SC)	+= rtc-imx-sc.o

obj-$(CONFIG_RTC_DRV_ISL12022)	+= rtc-isl12022.o

obj-$(CONFIG_RTC_DRV_ISL12026)	+= rtc-isl12026.o

obj-$(CONFIG_RTC_DRV_ISL1208)	+= rtc-isl1208.o

drivers/rtc/rtc-imx-sc.c

0 → 100644
+91 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0+

/*

 * Copyright 2018 NXP.

 */



#include <linux/firmware/imx/sci.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/rtc.h>



#define IMX_SC_TIMER_FUNC_GET_RTC_SEC1970	9

#define IMX_SC_TIMER_FUNC_SET_RTC_TIME		6



static struct imx_sc_ipc *rtc_ipc_handle;

static struct rtc_device *imx_sc_rtc;



struct imx_sc_msg_timer_get_rtc_time {

	struct imx_sc_rpc_msg hdr;

	u32 time;

} __packed;



static int imx_sc_rtc_read_time(struct device *dev, struct rtc_time *tm)

{

	struct imx_sc_msg_timer_get_rtc_time msg;

	struct imx_sc_rpc_msg *hdr = &msg.hdr;

	int ret;



	hdr->ver = IMX_SC_RPC_VERSION;

	hdr->svc = IMX_SC_RPC_SVC_TIMER;

	hdr->func = IMX_SC_TIMER_FUNC_GET_RTC_SEC1970;

	hdr->size = 1;



	ret = imx_scu_call_rpc(rtc_ipc_handle, &msg, true);

	if (ret) {

		dev_err(dev, "read rtc time failed, ret %d\n", ret);

		return ret;

	}



	rtc_time_to_tm(msg.time, tm);



	return 0;

}



static const struct rtc_class_ops imx_sc_rtc_ops = {

	.read_time = imx_sc_rtc_read_time,

};



static int imx_sc_rtc_probe(struct platform_device *pdev)

{

	int ret;



	ret = imx_scu_get_handle(&rtc_ipc_handle);

	if (ret)

		return ret;



	imx_sc_rtc = devm_rtc_allocate_device(&pdev->dev);

	if (IS_ERR(imx_sc_rtc))

		return PTR_ERR(imx_sc_rtc);



	imx_sc_rtc->ops = &imx_sc_rtc_ops;

	imx_sc_rtc->range_min = 0;

	imx_sc_rtc->range_max = U32_MAX;



	ret = rtc_register_device(imx_sc_rtc);

	if (ret) {

		dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);

		return ret;

	}



	return 0;

}



static const struct of_device_id imx_sc_dt_ids[] = {

	{ .compatible = "fsl,imx8qxp-sc-rtc", },

	{}

};

MODULE_DEVICE_TABLE(of, imx_sc_dt_ids);



static struct platform_driver imx_sc_rtc_driver = {

	.driver = {

		.name	= "imx-sc-rtc",

		.of_match_table = imx_sc_dt_ids,

	},

	.probe		= imx_sc_rtc_probe,

};

module_platform_driver(imx_sc_rtc_driver);



MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");

MODULE_DESCRIPTION("NXP i.MX System Controller RTC Driver");

MODULE_LICENSE("GPL");

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