* [PATCH 0/2] rtc: Add ASPEED RTC
@ 2018-10-03 13:31 Joel Stanley
2018-10-03 13:31 ` [PATCH 1/2] rtc: Add ASPEED RTC driver Joel Stanley
2018-10-03 13:31 ` [PATCH 2/2] dt-bindings: rtc: Add ASPEED description Joel Stanley
0 siblings, 2 replies; 5+ messages in thread
From: Joel Stanley @ 2018-10-03 13:31 UTC (permalink / raw)
To: Alessandro Zummo, Alexandre Belloni, linux-rtc
Cc: Andrew Jeffery, Christian Svensson, linux-arm-kernel, linux-aspeed
This adds support for the ASPEED RTC hardware.
Joel Stanley (2):
rtc: Add ASPEED RTC driver
dt-bindings: rtc: Add ASPEED description
.../devicetree/bindings/rtc/rtc-aspeed.txt | 18 +++
drivers/rtc/Kconfig | 10 ++
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-aspeed.c | 142 ++++++++++++++++++
4 files changed, 171 insertions(+)
create mode 100644 Documentation/devicetree/bindings/rtc/rtc-aspeed.txt
create mode 100644 drivers/rtc/rtc-aspeed.c
--
2.17.1
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 1/2] rtc: Add ASPEED RTC driver
2018-10-03 13:31 [PATCH 0/2] rtc: Add ASPEED RTC Joel Stanley
@ 2018-10-03 13:31 ` Joel Stanley
2018-10-04 18:37 ` Alexandre Belloni
2018-10-03 13:31 ` [PATCH 2/2] dt-bindings: rtc: Add ASPEED description Joel Stanley
1 sibling, 1 reply; 5+ messages in thread
From: Joel Stanley @ 2018-10-03 13:31 UTC (permalink / raw)
To: Alessandro Zummo, Alexandre Belloni, linux-rtc
Cc: Andrew Jeffery, Christian Svensson, linux-arm-kernel, linux-aspeed
Read and writes the time to the non-battery backed RTC in the ASPEED
AST2400 and AST2500 system on chip.
Signed-off-by: Joel Stanley <joel@jms.id.au>
---
drivers/rtc/Kconfig | 10 +++
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-aspeed.c | 142 +++++++++++++++++++++++++++++++++++++++
3 files changed, 153 insertions(+)
create mode 100644 drivers/rtc/rtc-aspeed.c
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index a819ef07b7ec..372944b59b69 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1783,6 +1783,16 @@ config RTC_DRV_RTD119X
If you say yes here, you get support for the RTD1295 SoC
Real Time Clock.
+config RTC_DRV_ASPEED
+ tristate "Aspeed RTC"
+ depends on ARCH_ASPEED || COMPILE_TEST
+ help
+ If you say yes here you get support for the ASPEED AST2400 and
+ AST2500 SoC real time clocks.
+
+ This driver can also be built as a module, if so, the module
+ will be called "rtc-aspeed".
+
comment "HID Sensor RTC drivers"
config RTC_DRV_HID_SENSOR_TIME
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 290c1730fb0a..7d924577d133 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_RTC_DRV_AC100) += rtc-ac100.o
obj-$(CONFIG_RTC_DRV_ARMADA38X) += rtc-armada38x.o
obj-$(CONFIG_RTC_DRV_AS3722) += rtc-as3722.o
obj-$(CONFIG_RTC_DRV_ASM9260) += rtc-asm9260.o
+obj-$(CONFIG_RTC_DRV_ASPEED) += rtc-aspeed.o
obj-$(CONFIG_RTC_DRV_AT91RM9200)+= rtc-at91rm9200.o
obj-$(CONFIG_RTC_DRV_AT91SAM9) += rtc-at91sam9.o
obj-$(CONFIG_RTC_DRV_AU1XXX) += rtc-au1xxx.o
diff --git a/drivers/rtc/rtc-aspeed.c b/drivers/rtc/rtc-aspeed.c
new file mode 100644
index 000000000000..dce00e594910
--- /dev/null
+++ b/drivers/rtc/rtc-aspeed.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright 2015 IBM Corp.
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/io.h>
+
+struct aspeed_rtc {
+ struct rtc_device *rtc_dev;
+ void __iomem *base;
+ spinlock_t lock;
+};
+
+#define RTC_TIME 0x00
+#define RTC_YEAR 0x04
+#define RTC_CTRL 0x10
+
+#define RTC_UNLOCK 0x02
+#define RTC_ENABLE 0x01
+
+static int aspeed_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct aspeed_rtc *rtc = dev_get_drvdata(dev);
+ unsigned int cent, year, mon, day, hour, min, sec;
+ unsigned long flags;
+ u32 reg1, reg2;
+
+ spin_lock_irqsave(&rtc->lock, flags);
+
+ do {
+ reg2 = readl(rtc->base + RTC_YEAR);
+ reg1 = readl(rtc->base + RTC_TIME);
+ } while (reg2 != readl(rtc->base + RTC_YEAR));
+
+ day = (reg1 >> 24) & 0x1f;
+ hour = (reg1 >> 16) & 0x1f;
+ min = (reg1 >> 8) & 0x3f;
+ sec = (reg1 >> 0) & 0x3f;
+ cent = (reg2 >> 16) & 0x1f;
+ year = (reg2 >> 8) & 0x7f;
+ /*
+ * Month is 1-12 in hardware, and 0-11 in struct rtc_time, however we
+ * are using mktime64 which is 1-12, so no adjustment is necessary
+ */
+ mon = (reg2 >> 0) & 0x0f;
+
+ rtc_time64_to_tm(mktime64(cent * 100 + year, mon, day, hour, min, sec),
+ tm);
+
+ spin_unlock_irqrestore(&rtc->lock, flags);
+
+ return 0;
+}
+
+static int aspeed_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct aspeed_rtc *rtc = dev_get_drvdata(dev);
+ unsigned long flags;
+ u32 reg1, reg2, ctrl;
+ int year, cent;
+
+ spin_lock_irqsave(&rtc->lock, flags);
+
+ cent = (tm->tm_year + 1900) / 100;
+ year = tm->tm_year % 100;
+
+ reg1 = (tm->tm_mday << 24) | (tm->tm_hour << 16) | (tm->tm_min << 8) |
+ tm->tm_sec;
+
+ /* Hardware is 1-12, convert to 0-11 */
+ reg2 = ((cent & 0x1f) << 16) | ((year & 0x7f) << 8) |
+ ((tm->tm_mon & 0xf) + 1);
+
+ ctrl = readl(rtc->base + RTC_CTRL);
+ writel(ctrl | RTC_UNLOCK, rtc->base + RTC_CTRL);
+
+ writel(reg1, rtc->base + RTC_TIME);
+ writel(reg2, rtc->base + RTC_YEAR);
+
+ writel(ctrl, rtc->base + RTC_CTRL);
+
+ spin_unlock_irqrestore(&rtc->lock, flags);
+
+ return 0;
+}
+
+static const struct rtc_class_ops aspeed_rtc_ops = {
+ .read_time = aspeed_rtc_read_time,
+ .set_time = aspeed_rtc_set_time,
+};
+
+static int aspeed_rtc_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct aspeed_rtc *rtc;
+
+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rtc->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(rtc->base))
+ return PTR_ERR(rtc->base);
+
+ platform_set_drvdata(pdev, rtc);
+
+ rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &aspeed_rtc_ops, THIS_MODULE);
+
+ if (IS_ERR(rtc->rtc_dev))
+ return PTR_ERR(rtc->rtc_dev);
+
+ spin_lock_init(&rtc->lock);
+
+ /* Enable RTC and clear the unlock bit */
+ writel(RTC_ENABLE, rtc->base + RTC_CTRL);
+
+ return 0;
+}
+
+static const struct of_device_id aspeed_rtc_match[] = {
+ { .compatible = "aspeed,ast2400-rtc", },
+ { .compatible = "aspeed,ast2500-rtc", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, aspeed_rtc_match);
+
+static struct platform_driver aspeed_rtc_driver = {
+ .driver = {
+ .name = "aspeed-rtc",
+ .of_match_table = of_match_ptr(aspeed_rtc_match),
+ },
+};
+
+module_platform_driver_probe(aspeed_rtc_driver, aspeed_rtc_probe);
+
+MODULE_DESCRIPTION("Aspeed RTC driver");
+MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>");
+MODULE_LICENSE("GPL");
--
2.17.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 2/2] dt-bindings: rtc: Add ASPEED description
2018-10-03 13:31 [PATCH 0/2] rtc: Add ASPEED RTC Joel Stanley
2018-10-03 13:31 ` [PATCH 1/2] rtc: Add ASPEED RTC driver Joel Stanley
@ 2018-10-03 13:31 ` Joel Stanley
2018-10-04 18:37 ` Alexandre Belloni
1 sibling, 1 reply; 5+ messages in thread
From: Joel Stanley @ 2018-10-03 13:31 UTC (permalink / raw)
To: Alessandro Zummo, Alexandre Belloni, linux-rtc
Cc: Andrew Jeffery, Christian Svensson, linux-arm-kernel, linux-aspeed
Describe the RTC as used in the ASPEED ast2400 and ast2500 SoCs.
Signed-off-by: Joel Stanley <joel@jms.id.au>
---
.../devicetree/bindings/rtc/rtc-aspeed.txt | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
create mode 100644 Documentation/devicetree/bindings/rtc/rtc-aspeed.txt
diff --git a/Documentation/devicetree/bindings/rtc/rtc-aspeed.txt b/Documentation/devicetree/bindings/rtc/rtc-aspeed.txt
new file mode 100644
index 000000000000..d31a4d24c75f
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/rtc-aspeed.txt
@@ -0,0 +1,18 @@
+ASPEED BMC RTC
+==============
+
+Required properties:
+ - compatible: should be one of the following
+ * aspeed,ast2400-rtc for the ast2400
+ * aspeed,ast2500-rtc for the ast2500
+
+ - reg: physical base address of the controller and length of memory mapped
+ region
+
+Example:
+
+ rtc@1e781000 {
+ compatible = "aspeed,ast2400-rtc";
+ reg = <0x1e781000 0x18>;
+ status = "disabled";
+ };
--
2.17.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 1/2] rtc: Add ASPEED RTC driver
2018-10-03 13:31 ` [PATCH 1/2] rtc: Add ASPEED RTC driver Joel Stanley
@ 2018-10-04 18:37 ` Alexandre Belloni
0 siblings, 0 replies; 5+ messages in thread
From: Alexandre Belloni @ 2018-10-04 18:37 UTC (permalink / raw)
To: Joel Stanley
Cc: Alessandro Zummo, linux-rtc, Andrew Jeffery, Christian Svensson,
linux-arm-kernel, linux-aspeed
Hello,
On 03/10/2018 15:31:54+0200, Joel Stanley wrote:
> +static int aspeed_rtc_read_time(struct device *dev, struct rtc_time *tm)
> +{
> + struct aspeed_rtc *rtc = dev_get_drvdata(dev);
> + unsigned int cent, year, mon, day, hour, min, sec;
> + unsigned long flags;
> + u32 reg1, reg2;
> +
> + spin_lock_irqsave(&rtc->lock, flags);
> +
> + do {
> + reg2 = readl(rtc->base + RTC_YEAR);
> + reg1 = readl(rtc->base + RTC_TIME);
> + } while (reg2 != readl(rtc->base + RTC_YEAR));
> +
> + day = (reg1 >> 24) & 0x1f;
> + hour = (reg1 >> 16) & 0x1f;
> + min = (reg1 >> 8) & 0x3f;
> + sec = (reg1 >> 0) & 0x3f;
> + cent = (reg2 >> 16) & 0x1f;
> + year = (reg2 >> 8) & 0x7f;
> + /*
> + * Month is 1-12 in hardware, and 0-11 in struct rtc_time, however we
> + * are using mktime64 which is 1-12, so no adjustment is necessary
> + */
> + mon = (reg2 >> 0) & 0x0f;
> +
> + rtc_time64_to_tm(mktime64(cent * 100 + year, mon, day, hour, min, sec),
> + tm);
> +
This is quite wasteful. You already have the broken out time. Why don't
you directly fill the tm struct?
> +static int aspeed_rtc_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct aspeed_rtc *rtc;
> +
> + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
> + if (!rtc)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + rtc->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(rtc->base))
> + return PTR_ERR(rtc->base);
> +
> + platform_set_drvdata(pdev, rtc);
> +
> + rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name,
> + &aspeed_rtc_ops, THIS_MODULE);
> +
Please use devm_rtc_allocate_device to allocate the rtc and then
register it with rtc_register_device. Please also fill
rtc->range_{min,max} before the registration.
> + if (IS_ERR(rtc->rtc_dev))
> + return PTR_ERR(rtc->rtc_dev);
> +
> + spin_lock_init(&rtc->lock);
> +
> + /* Enable RTC and clear the unlock bit */
> + writel(RTC_ENABLE, rtc->base + RTC_CTRL);
> +
Maybe this should only be done in set_time so you can know whether the
time that is read in read_time has a chance to be valid.
For example you could return -EINVAL when RTC_ENABLE is not set if this
bit is readable.
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 2/2] dt-bindings: rtc: Add ASPEED description
2018-10-03 13:31 ` [PATCH 2/2] dt-bindings: rtc: Add ASPEED description Joel Stanley
@ 2018-10-04 18:37 ` Alexandre Belloni
0 siblings, 0 replies; 5+ messages in thread
From: Alexandre Belloni @ 2018-10-04 18:37 UTC (permalink / raw)
To: Joel Stanley
Cc: Alessandro Zummo, linux-rtc, Andrew Jeffery, Christian Svensson,
linux-arm-kernel, linux-aspeed
I think this patch should come first.
On 03/10/2018 15:31:55+0200, Joel Stanley wrote:
> Describe the RTC as used in the ASPEED ast2400 and ast2500 SoCs.
>
> Signed-off-by: Joel Stanley <joel@jms.id.au>
> ---
> .../devicetree/bindings/rtc/rtc-aspeed.txt | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/rtc/rtc-aspeed.txt
>
> diff --git a/Documentation/devicetree/bindings/rtc/rtc-aspeed.txt b/Documentation/devicetree/bindings/rtc/rtc-aspeed.txt
> new file mode 100644
> index 000000000000..d31a4d24c75f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/rtc/rtc-aspeed.txt
> @@ -0,0 +1,18 @@
> +ASPEED BMC RTC
> +==============
> +
> +Required properties:
> + - compatible: should be one of the following
> + * aspeed,ast2400-rtc for the ast2400
> + * aspeed,ast2500-rtc for the ast2500
> +
> + - reg: physical base address of the controller and length of memory mapped
> + region
> +
> +Example:
> +
> + rtc@1e781000 {
> + compatible = "aspeed,ast2400-rtc";
> + reg = <0x1e781000 0x18>;
> + status = "disabled";
> + };
> --
> 2.17.1
>
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2018-10-04 18:37 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2018-10-03 13:31 [PATCH 0/2] rtc: Add ASPEED RTC Joel Stanley
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2018-10-04 18:37 ` Alexandre Belloni
2018-10-03 13:31 ` [PATCH 2/2] dt-bindings: rtc: Add ASPEED description Joel Stanley
2018-10-04 18:37 ` Alexandre Belloni
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