* [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC
@ 2019-06-07 19:43 Kevin Hilman
2019-06-07 19:43 ` [PATCH 2/2] rtc: Add Amlogic Virtual Wake RTC Kevin Hilman
2019-07-09 2:07 ` [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC Rob Herring
0 siblings, 2 replies; 4+ messages in thread
From: Kevin Hilman @ 2019-06-07 19:43 UTC (permalink / raw)
To: linux-rtc, Alexandre Belloni
Cc: linux-amlogic, linux-arm-kernel, linux-kernel, devicetree, Kevin Hilman
From: Kevin Hilman <khilman@baylibre.com>
Add binding fo the new VRTC driver for Amlogic SoCs. The 64-bit
family of SoCs only has an RTC managed by firmware, and this VRTC
driver provides the simple, one-register firmware interface.
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
---
.../devicetree/bindings/rtc/rtc-meson-vrtc.txt | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
create mode 100644 Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt
diff --git a/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt b/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt
new file mode 100644
index 000000000000..f02886179788
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt
@@ -0,0 +1,16 @@
+* Amlogic Virtual RTC (VRTC)
+
+This is a Linux interface to an RTC managed by firmware, hence it's
+virtual from a Linux perspective. The interface is 1 register where
+an alarm time is to be written.
+
+Required properties:
+- compatible: should be "amlogic,meson-vrtc"
+- reg: physical address for the alarm register
+
+Example:
+
+ vrtc: rtc@0a8 {
+ compatible = "amlogic,meson-vrtc";
+ reg = <0x0 0x000a8 0x0 0x4>;
+ };
--
2.21.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/2] rtc: Add Amlogic Virtual Wake RTC
2019-06-07 19:43 [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC Kevin Hilman
@ 2019-06-07 19:43 ` Kevin Hilman
2019-06-20 21:17 ` Alexandre Belloni
2019-07-09 2:07 ` [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC Rob Herring
1 sibling, 1 reply; 4+ messages in thread
From: Kevin Hilman @ 2019-06-07 19:43 UTC (permalink / raw)
To: linux-rtc, Alexandre Belloni
Cc: linux-amlogic, linux-arm-kernel, linux-kernel, devicetree,
Neil Armstrong, Kevin Hilman
From: Neil Armstrong <narmstrong@baylibre.com>
The 64-bit Amlogic SoCs uses a special register to store the time in
seconds to wakeup after a system suspend.
In order to be able to reuse the RTC wakealarm feature, this
driver implements a fake RTC device which uses the system time
to deduce a suspend delay.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[khilman: rebase to v5.2-rc, moved from do_gettimeofday()]
Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
---
Originally written/sumbmitted by Neil as part of a broader/suspend
resume series[1] for the GXBB family. Newer SoCs support PSCI
properly, so don't need the PSCI changes there, and this driver alone
enables RTC wakeups from suspend.
[1] https://lore.kernel.org/lkml/1478183365-23708-1-git-send-email-narmstrong@baylibre.com/
drivers/rtc/Kconfig | 11 +++
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-meson-vrtc.c | 149 +++++++++++++++++++++++++++++++++++
3 files changed, 161 insertions(+)
create mode 100644 drivers/rtc/rtc-meson-vrtc.c
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 5c0790eed656..78d2967d5ee3 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -373,6 +373,17 @@ config RTC_DRV_MAX77686
This driver can also be built as a module. If so, the module
will be called rtc-max77686.
+config RTC_DRV_MESON_VRTC
+ tristate "Amlogic Meson Virtual RTC"
+ depends on ARCH_MESON || COMPILE_TEST
+ default m if ARCH_MESON
+ help
+ If you say yes here you will get support for the
+ Virtual RTC of Amlogic SoCs.
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-meson-vrtc.
+
config RTC_DRV_RK808
tristate "Rockchip RK805/RK808/RK818 RTC"
depends on MFD_RK808
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 9d997faa2c26..9485fb46b023 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -101,6 +101,7 @@ obj-$(CONFIG_RTC_DRV_MAX8907) += rtc-max8907.o
obj-$(CONFIG_RTC_DRV_MAX8925) += rtc-max8925.o
obj-$(CONFIG_RTC_DRV_MAX8997) += rtc-max8997.o
obj-$(CONFIG_RTC_DRV_MAX8998) += rtc-max8998.o
+obj-$(CONFIG_RTC_DRV_MESON_VRTC)+= rtc-meson-vrtc.o
obj-$(CONFIG_RTC_DRV_MC13XXX) += rtc-mc13xxx.o
obj-$(CONFIG_RTC_DRV_MCP795) += rtc-mcp795.o
obj-$(CONFIG_RTC_DRV_MESON) += rtc-meson.o
diff --git a/drivers/rtc/rtc-meson-vrtc.c b/drivers/rtc/rtc-meson-vrtc.c
new file mode 100644
index 000000000000..f695f65ab199
--- /dev/null
+++ b/drivers/rtc/rtc-meson-vrtc.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
+ */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/time64.h>
+
+struct meson_vrtc_data {
+ struct platform_device *pdev;
+ void __iomem *io_alarm;
+ struct rtc_device *rtc;
+ unsigned long alarm_time;
+};
+
+static int meson_vrtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned long local_time;
+ struct timespec64 time;
+
+ ktime_get_raw_ts64(&time);
+ local_time = time.tv_sec - (sys_tz.tz_minuteswest * 60);
+ rtc_time_to_tm(local_time, tm);
+
+ return 0;
+}
+
+static void meson_vrtc_set_wakeup_time(struct meson_vrtc_data *vrtc,
+ unsigned long time)
+{
+ writel_relaxed(time, vrtc->io_alarm);
+
+ dev_dbg(&vrtc->pdev->dev, "set_wakeup_time: %lu\n", time);
+}
+
+static int meson_vrtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
+ struct timespec64 time;
+ unsigned long local_time;
+ unsigned long alarm_secs;
+ int ret;
+
+ if (alarm->enabled) {
+ ret = rtc_tm_to_time(&alarm->time, &alarm_secs);
+ if (ret)
+ return ret;
+
+ ktime_get_raw_ts64(&time);
+ local_time = time.tv_sec - (sys_tz.tz_minuteswest * 60);
+
+ vrtc->alarm_time = alarm_secs;
+
+ if (alarm_secs >= local_time) {
+ alarm_secs = alarm_secs - local_time;
+
+ meson_vrtc_set_wakeup_time(vrtc, alarm_secs);
+
+ pr_debug("system will wakeup %lus later\n", alarm_secs);
+ }
+ } else {
+ vrtc->alarm_time = 0;
+ meson_vrtc_set_wakeup_time(vrtc, 0);
+ }
+
+ return 0;
+}
+
+static int meson_vrtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
+
+ if (!vrtc->alarm_time) {
+ alm->enabled = true;
+
+ rtc_time_to_tm(vrtc->alarm_time, &alm->time);
+ }
+
+ return 0;
+}
+
+static const struct rtc_class_ops meson_vrtc_ops = {
+ .read_time = meson_vrtc_read_time,
+ .set_alarm = meson_vrtc_set_alarm,
+ .read_alarm = meson_vrtc_read_alarm,
+};
+
+static int meson_vrtc_probe(struct platform_device *pdev)
+{
+ struct meson_vrtc_data *vrtc;
+ struct resource *res;
+
+ vrtc = devm_kzalloc(&pdev->dev, sizeof(*vrtc), GFP_KERNEL);
+ if (!vrtc)
+ return -ENOMEM;
+
+ vrtc->pdev = pdev;
+
+ /* Alarm registers */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ vrtc->io_alarm = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(vrtc->io_alarm))
+ return PTR_ERR(vrtc->io_alarm);
+
+ device_init_wakeup(&pdev->dev, 1);
+
+ platform_set_drvdata(pdev, vrtc);
+
+ vrtc->rtc = devm_rtc_device_register(&pdev->dev, "meson-vrtc",
+ &meson_vrtc_ops, THIS_MODULE);
+ if (IS_ERR(vrtc->rtc))
+ return PTR_ERR(vrtc->rtc);
+
+ return 0;
+}
+
+int meson_vrtc_resume(struct platform_device *pdev)
+{
+ struct meson_vrtc_data *vrtc = platform_get_drvdata(pdev);
+
+ meson_vrtc_set_wakeup_time(vrtc, 0);
+
+ return 0;
+}
+
+static const struct of_device_id meson_vrtc_dt_match[] = {
+ { .compatible = "amlogic,meson-vrtc"},
+ {},
+};
+MODULE_DEVICE_TABLE(of, meson_vrtc_dt_match);
+
+struct platform_driver meson_vrtc_driver = {
+ .driver = {
+ .name = "meson-vrtc",
+ .of_match_table = meson_vrtc_dt_match,
+ },
+ .probe = meson_vrtc_probe,
+ .resume = meson_vrtc_resume,
+};
+
+module_platform_driver(meson_vrtc_driver);
+
+MODULE_DESCRIPTION("Amlogic Virtual Wakeup RTC Timer driver");
+MODULE_LICENSE("GPL");
--
2.21.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 2/2] rtc: Add Amlogic Virtual Wake RTC
2019-06-07 19:43 ` [PATCH 2/2] rtc: Add Amlogic Virtual Wake RTC Kevin Hilman
@ 2019-06-20 21:17 ` Alexandre Belloni
0 siblings, 0 replies; 4+ messages in thread
From: Alexandre Belloni @ 2019-06-20 21:17 UTC (permalink / raw)
To: Kevin Hilman
Cc: linux-rtc, linux-amlogic, linux-arm-kernel, linux-kernel,
devicetree, Neil Armstrong, Kevin Hilman
Hello Kevin,
On 07/06/2019 12:43:43-0700, Kevin Hilman wrote:
> +static int meson_vrtc_read_time(struct device *dev, struct rtc_time *tm)
> +{
> + unsigned long local_time;
> + struct timespec64 time;
> +
> + ktime_get_raw_ts64(&time);
> + local_time = time.tv_sec - (sys_tz.tz_minuteswest * 60);
The RTC is supposed to be set to UTC so the TZ adjustment is not
necessary.
> + rtc_time_to_tm(local_time, tm);
> +
Please use the 64 bit version.
> + return 0;
> +}
> +
> +static void meson_vrtc_set_wakeup_time(struct meson_vrtc_data *vrtc,
> + unsigned long time)
> +{
> + writel_relaxed(time, vrtc->io_alarm);
> +
> + dev_dbg(&vrtc->pdev->dev, "set_wakeup_time: %lu\n", time);
> +}
> +
> +static int meson_vrtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
> +{
> + struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
> + struct timespec64 time;
> + unsigned long local_time;
> + unsigned long alarm_secs;
> + int ret;
> +
> + if (alarm->enabled) {
> + ret = rtc_tm_to_time(&alarm->time, &alarm_secs);
> + if (ret)
> + return ret;
> +
Use the 64bit version which makes it clear that it never fails (checking
ret is useless).
> + ktime_get_raw_ts64(&time);
> + local_time = time.tv_sec - (sys_tz.tz_minuteswest * 60);
> +
> + vrtc->alarm_time = alarm_secs;
> +
> + if (alarm_secs >= local_time) {
This is already ensured by the core so no need to check here.
> + alarm_secs = alarm_secs - local_time;
> +
> + meson_vrtc_set_wakeup_time(vrtc, alarm_secs);
> +
> + pr_debug("system will wakeup %lus later\n", alarm_secs);
> + }
> + } else {
> + vrtc->alarm_time = 0;
> + meson_vrtc_set_wakeup_time(vrtc, 0);
> + }
> +
> + return 0;
> +}
> +
> +static int meson_vrtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
> +{
> + struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
> +
> + if (!vrtc->alarm_time) {
I think this test is inverted.
> + alm->enabled = true;
> +
> + rtc_time_to_tm(vrtc->alarm_time, &alm->time);
> + }
> +
> + return 0;
> +}
> +
> +static const struct rtc_class_ops meson_vrtc_ops = {
> + .read_time = meson_vrtc_read_time,
> + .set_alarm = meson_vrtc_set_alarm,
> + .read_alarm = meson_vrtc_read_alarm,
> +};
> +
> +static int meson_vrtc_probe(struct platform_device *pdev)
> +{
> + struct meson_vrtc_data *vrtc;
> + struct resource *res;
> +
> + vrtc = devm_kzalloc(&pdev->dev, sizeof(*vrtc), GFP_KERNEL);
> + if (!vrtc)
> + return -ENOMEM;
> +
> + vrtc->pdev = pdev;
> +
> + /* Alarm registers */
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + vrtc->io_alarm = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(vrtc->io_alarm))
> + return PTR_ERR(vrtc->io_alarm);
> +
> + device_init_wakeup(&pdev->dev, 1);
> +
> + platform_set_drvdata(pdev, vrtc);
> +
> + vrtc->rtc = devm_rtc_device_register(&pdev->dev, "meson-vrtc",
> + &meson_vrtc_ops, THIS_MODULE);
> + if (IS_ERR(vrtc->rtc))
> + return PTR_ERR(vrtc->rtc);
> +
Please use devm_rtc_allocate_device and rtc_register_device. This
doesn't help much but my plan is to get rid of devm_rtc_device_register.
I suppose you don't get any interrupt for the alarm?
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC
2019-06-07 19:43 [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC Kevin Hilman
2019-06-07 19:43 ` [PATCH 2/2] rtc: Add Amlogic Virtual Wake RTC Kevin Hilman
@ 2019-07-09 2:07 ` Rob Herring
1 sibling, 0 replies; 4+ messages in thread
From: Rob Herring @ 2019-07-09 2:07 UTC (permalink / raw)
To: Kevin Hilman
Cc: linux-rtc, Alexandre Belloni, linux-amlogic, linux-arm-kernel,
linux-kernel, devicetree, Kevin Hilman
On Fri, 7 Jun 2019 12:43:42 -0700, Kevin Hilman wrote:
> From: Kevin Hilman <khilman@baylibre.com>
>
> Add binding fo the new VRTC driver for Amlogic SoCs. The 64-bit
> family of SoCs only has an RTC managed by firmware, and this VRTC
> driver provides the simple, one-register firmware interface.
>
> Signed-off-by: Kevin Hilman <khilman@baylibre.com>
> ---
> .../devicetree/bindings/rtc/rtc-meson-vrtc.txt | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt
>
Reviewed-by: Rob Herring <robh@kernel.org>
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2019-07-09 2:07 UTC | newest]
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2019-06-07 19:43 [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC Kevin Hilman
2019-06-07 19:43 ` [PATCH 2/2] rtc: Add Amlogic Virtual Wake RTC Kevin Hilman
2019-06-20 21:17 ` Alexandre Belloni
2019-07-09 2:07 ` [PATCH 1/2] dt-bindings: rtc: new binding for Amlogic VRTC Rob Herring
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