| Message ID | 20220421090016.79517-4-miquel.raynal@bootlin.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | RZN1 RTC support | expand |
Hi Miquel, On Thu, Apr 21, 2022 at 11:00 AM Miquel Raynal <miquel.raynal@bootlin.com> wrote: > From: Michel Pollet <michel.pollet@bp.renesas.com> > > Add a basic RTC driver for the RZ/N1. > > Signed-off-by: Michel Pollet <michel.pollet@bp.renesas.com> > Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com> > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Thanks for your patch! > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -1548,6 +1548,13 @@ config RTC_DRV_RS5C313 > help > If you say yes here you get support for the Ricoh RS5C313 RTC chips. > > +config RTC_DRV_RZN1 > + tristate "Renesas RZN1 RTC" RZ/N1 > + depends on ARCH_RZN1 || COMPILE_TEST > + depends on OF && HAS_IOMEM > + help > + If you say yes here you get support for the Renesas RZ/N1 RTC. > + > config RTC_DRV_GENERIC > tristate "Generic RTC support" > # Please consider writing a new RTC driver instead of using the generic > --- /dev/null > +++ b/drivers/rtc/rtc-rzn1.c > +static int rzn1_rtc_probe(struct platform_device *pdev) > +{ > + struct rzn1_rtc *rtc; > + int ret; > + > + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); > + if (!rtc) > + return -ENOMEM; > + > + platform_set_drvdata(pdev, rtc); > + > + rtc->clk = devm_clk_get(&pdev->dev, "hclk"); > + if (IS_ERR(rtc->clk)) > + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->clk), "Missing hclk\n"); As you don't care about the clock rate, only about enabling/disabling the clock, I recommend using Runtime PM instead of explicit clock handling. That does depend on: [PATCH v3 4/8] soc: renesas: rzn1: Select PM and PM_GENERIC_DOMAINS configs[1] [PATCH v3 5/8] ARM: dts: r9a06g032: Add missing '#power-domain-cells'[2] and on documenting the power-domains property to the RTC DT bindings, and on adding a proper power-domains property to the RTC node in DTS. [1] https://lore.kernel.org/linux-renesas-soc/20220422120850.769480-5-herve.codina@bootlin.com [2] https://lore.kernel.org/linux-renesas-soc/20220422120850.769480-6-herve.codina@bootlin.com Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
Hi Geert, geert@linux-m68k.org wrote on Thu, 28 Apr 2022 10:58:03 +0200: > Hi Miquel, > > On Thu, Apr 21, 2022 at 11:00 AM Miquel Raynal > <miquel.raynal@bootlin.com> wrote: > > From: Michel Pollet <michel.pollet@bp.renesas.com> > > > > Add a basic RTC driver for the RZ/N1. > > > > Signed-off-by: Michel Pollet <michel.pollet@bp.renesas.com> > > Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com> > > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> > > Thanks for your patch! > > > --- a/drivers/rtc/Kconfig > > +++ b/drivers/rtc/Kconfig > > @@ -1548,6 +1548,13 @@ config RTC_DRV_RS5C313 > > help > > If you say yes here you get support for the Ricoh RS5C313 RTC chips. > > > > +config RTC_DRV_RZN1 > > + tristate "Renesas RZN1 RTC" > > RZ/N1 > > > + depends on ARCH_RZN1 || COMPILE_TEST > > + depends on OF && HAS_IOMEM > > + help > > + If you say yes here you get support for the Renesas RZ/N1 RTC. > > + > > config RTC_DRV_GENERIC > > tristate "Generic RTC support" > > # Please consider writing a new RTC driver instead of using the generic > > > --- /dev/null > > +++ b/drivers/rtc/rtc-rzn1.c > > > +static int rzn1_rtc_probe(struct platform_device *pdev) > > +{ > > + struct rzn1_rtc *rtc; > > + int ret; > > + > > + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); > > + if (!rtc) > > + return -ENOMEM; > > + > > + platform_set_drvdata(pdev, rtc); > > + > > + rtc->clk = devm_clk_get(&pdev->dev, "hclk"); > > + if (IS_ERR(rtc->clk)) > > + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->clk), "Missing hclk\n"); > > As you don't care about the clock rate, only about enabling/disabling > the clock, I recommend using Runtime PM instead of explicit clock > handling. That's right. > That does depend on: > [PATCH v3 4/8] soc: renesas: rzn1: Select PM and PM_GENERIC_DOMAINS configs[1] > [PATCH v3 5/8] ARM: dts: r9a06g032: Add missing '#power-domain-cells'[2] There should not be any dependency with the RTC tree so that should not be too complex to handle. > and on documenting the power-domains property to the RTC DT bindings, > and on adding a proper power-domains property to the RTC node in DTS. Right. Do we need to define these properties in the UART, DMA and NAND controller nodes as well? I seem to remember that you mentioned it but I don't recall for which one and I was too focused (lazy?) on other features so I forgot about it. > [1] https://lore.kernel.org/linux-renesas-soc/20220422120850.769480-5-herve.codina@bootlin.com > [2] https://lore.kernel.org/linux-renesas-soc/20220422120850.769480-6-herve.codina@bootlin.com Thanks, Miquèl
Hi Miquel, On Thu, Apr 28, 2022 at 11:09 AM Miquel Raynal <miquel.raynal@bootlin.com> wrote: > geert@linux-m68k.org wrote on Thu, 28 Apr 2022 10:58:03 +0200: > > On Thu, Apr 21, 2022 at 11:00 AM Miquel Raynal > > <miquel.raynal@bootlin.com> wrote: > > > From: Michel Pollet <michel.pollet@bp.renesas.com> > > > > > > Add a basic RTC driver for the RZ/N1. > > > > > > Signed-off-by: Michel Pollet <michel.pollet@bp.renesas.com> > > > Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com> > > > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> > > > --- /dev/null > > > +++ b/drivers/rtc/rtc-rzn1.c > > > > > +static int rzn1_rtc_probe(struct platform_device *pdev) > > > +{ > > > + struct rzn1_rtc *rtc; > > > + int ret; > > > + > > > + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); > > > + if (!rtc) > > > + return -ENOMEM; > > > + > > > + platform_set_drvdata(pdev, rtc); > > > + > > > + rtc->clk = devm_clk_get(&pdev->dev, "hclk"); > > > + if (IS_ERR(rtc->clk)) > > > + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->clk), "Missing hclk\n"); > > > > As you don't care about the clock rate, only about enabling/disabling > > the clock, I recommend using Runtime PM instead of explicit clock > > handling. > > That's right. > > > That does depend on: > > [PATCH v3 4/8] soc: renesas: rzn1: Select PM and PM_GENERIC_DOMAINS configs[1] > > [PATCH v3 5/8] ARM: dts: r9a06g032: Add missing '#power-domain-cells'[2] > > There should not be any dependency with the RTC tree so that should not > be too complex to handle. Agreed. > > and on documenting the power-domains property to the RTC DT bindings, > > and on adding a proper power-domains property to the RTC node in DTS. > > Right. > > Do we need to define these properties in the UART, DMA and NAND > controller nodes as well? I seem to remember that you mentioned it but > I don't recall for which one and I was too focused (lazy?) on other > features so I forgot about it. It would be good to have them everywhere. The initial RZ/N1D DTS lacked them, as it only had the uart driver, which is not a Renesas IP core. The dw-dmac and 8250_dw drivers already use Runtime PM. The renesas-nand-controller driver can be updated later, after the power-domains properties have been added to the DTS. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 41c65b4d2baf..f4d72c5b99ea 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -1548,6 +1548,13 @@ config RTC_DRV_RS5C313 help If you say yes here you get support for the Ricoh RS5C313 RTC chips. +config RTC_DRV_RZN1 + tristate "Renesas RZN1 RTC" + depends on ARCH_RZN1 || COMPILE_TEST + depends on OF && HAS_IOMEM + help + If you say yes here you get support for the Renesas RZ/N1 RTC. + config RTC_DRV_GENERIC tristate "Generic RTC support" # Please consider writing a new RTC driver instead of using the generic diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 2d827d8261d5..fb04467b652d 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -151,6 +151,7 @@ obj-$(CONFIG_RTC_DRV_RX6110) += rtc-rx6110.o obj-$(CONFIG_RTC_DRV_RX8010) += rtc-rx8010.o obj-$(CONFIG_RTC_DRV_RX8025) += rtc-rx8025.o obj-$(CONFIG_RTC_DRV_RX8581) += rtc-rx8581.o +obj-$(CONFIG_RTC_DRV_RZN1) += rtc-rzn1.o obj-$(CONFIG_RTC_DRV_S35390A) += rtc-s35390a.o obj-$(CONFIG_RTC_DRV_S3C) += rtc-s3c.o obj-$(CONFIG_RTC_DRV_S5M) += rtc-s5m.o diff --git a/drivers/rtc/rtc-rzn1.c b/drivers/rtc/rtc-rzn1.c new file mode 100644 index 000000000000..a5dfb5bb163c --- /dev/null +++ b/drivers/rtc/rtc-rzn1.c @@ -0,0 +1,250 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Renesas RZN1 Real Time Clock interface for Linux + * + * Copyright: + * - 2014 Renesas Electronics Europe Limited + * - 2022 Schneider Electric + * + * Authors: + * - Michel Pollet <michel.pollet@bp.renesas.com>, <buserror@gmail.com> + * - Miquel Raynal <miquel.raynal@bootlin.com> + */ + +#include <linux/bcd.h> +#include <linux/clk.h> +#include <linux/init.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> +#include <linux/soc/renesas/r9a06g032-sysctrl.h> + +#define RZN1_RTC_CTL0 0x00 +#define RZN1_RTC_CTL0_SLSB_SUBU 0 +#define RZN1_RTC_CTL0_SLSB_SCMP BIT(4) +#define RZN1_RTC_CTL0_AMPM BIT(5) +#define RZN1_RTC_CTL0_CE BIT(7) + +#define RZN1_RTC_CTL1 0x04 +#define RZN1_RTC_CTL1_ALME BIT(4) + +#define RZN1_RTC_CTL2 0x08 +#define RZN1_RTC_CTL2_WAIT BIT(0) +#define RZN1_RTC_CTL2_WST BIT(1) +#define RZN1_RTC_CTL2_WUST BIT(5) +#define RZN1_RTC_CTL2_STOPPED (RZN1_RTC_CTL2_WAIT | RZN1_RTC_CTL2_WST) + +#define RZN1_RTC_SEC 0x14 +#define RZN1_RTC_MIN 0x18 +#define RZN1_RTC_HOUR 0x1c +#define RZN1_RTC_WEEK 0x20 +#define RZN1_RTC_DAY 0x24 +#define RZN1_RTC_MONTH 0x28 +#define RZN1_RTC_YEAR 0x2c + +#define RZN1_RTC_SUBU 0x38 +#define RZN1_RTC_SUBU_DEV BIT(7) +#define RZN1_RTC_SUBU_DECR BIT(6) + +#define RZN1_RTC_ALM 0x40 +#define RZN1_RTC_ALH 0x44 +#define RZN1_RTC_ALW 0x48 + +#define RZN1_RTC_SECC 0x4c +#define RZN1_RTC_MINC 0x50 +#define RZN1_RTC_HOURC 0x54 +#define RZN1_RTC_WEEKC 0x58 +#define RZN1_RTC_DAYC 0x5c +#define RZN1_RTC_MONTHC 0x60 +#define RZN1_RTC_YEARC 0x64 + +struct rzn1_rtc { + struct rtc_device *rtcdev; + void __iomem *base; + struct clk *clk; +}; + +static void rzn1_rtc_get_time_snapshot(struct rzn1_rtc *rtc, struct rtc_time *tm) +{ + tm->tm_sec = readl(rtc->base + RZN1_RTC_SECC); + tm->tm_min = readl(rtc->base + RZN1_RTC_MINC); + tm->tm_hour = readl(rtc->base + RZN1_RTC_HOURC); + tm->tm_wday = readl(rtc->base + RZN1_RTC_WEEKC); + tm->tm_mday = readl(rtc->base + RZN1_RTC_DAYC); + tm->tm_mon = readl(rtc->base + RZN1_RTC_MONTHC); + tm->tm_year = readl(rtc->base + RZN1_RTC_YEARC); +} + +static unsigned int rzn1_rtc_tm_to_wday(struct rtc_time *tm) +{ + time64_t time; + unsigned int days; + u32 secs; + + time = rtc_tm_to_time64(tm); + days = div_s64_rem(time, 86400, &secs); + + /* day of the week, 1970-01-01 was a Thursday */ + return (days + 4) % 7; +} + +static int rzn1_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct rzn1_rtc *rtc = dev_get_drvdata(dev); + u32 val, secs; + + /* + * The RTC was not started or is stopped and thus does not carry the + * proper time/date. + */ + val = readl(rtc->base + RZN1_RTC_CTL2); + if (val & RZN1_RTC_CTL2_STOPPED) + return -EINVAL; + + rzn1_rtc_get_time_snapshot(rtc, tm); + secs = readl(rtc->base + RZN1_RTC_SECC); + if (tm->tm_sec != secs) + rzn1_rtc_get_time_snapshot(rtc, tm); + + tm->tm_sec = bcd2bin(tm->tm_sec); + tm->tm_min = bcd2bin(tm->tm_min); + tm->tm_hour = bcd2bin(tm->tm_hour); + tm->tm_wday = bcd2bin(tm->tm_wday); + tm->tm_mday = bcd2bin(tm->tm_mday); + tm->tm_mon = bcd2bin(tm->tm_mon); + tm->tm_year = bcd2bin(tm->tm_year); + + return 0; +} + +static int rzn1_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct rzn1_rtc *rtc = dev_get_drvdata(dev); + u32 val; + int ret; + + tm->tm_sec = bin2bcd(tm->tm_sec); + tm->tm_min = bin2bcd(tm->tm_min); + tm->tm_hour = bin2bcd(tm->tm_hour); + tm->tm_wday = bin2bcd(rzn1_rtc_tm_to_wday(tm)); + tm->tm_mday = bin2bcd(tm->tm_mday); + tm->tm_mon = bin2bcd(tm->tm_mon); + tm->tm_year = bin2bcd(tm->tm_year); + + val = readl(rtc->base + RZN1_RTC_CTL2); + if (!(val & RZN1_RTC_CTL2_STOPPED)) { + /* Hold the counter if it was counting up */ + writel(RZN1_RTC_CTL2_WAIT, rtc->base + RZN1_RTC_CTL2); + + /* Wait for the counter to stop: two 32k clock cycles */ + usleep_range(61, 100); + ret = readl_poll_timeout(rtc->base + RZN1_RTC_CTL2, val, + val & RZN1_RTC_CTL2_WST, 0, 100); + if (ret) + return ret; + } + + writel(tm->tm_sec, rtc->base + RZN1_RTC_SEC); + writel(tm->tm_min, rtc->base + RZN1_RTC_MIN); + writel(tm->tm_hour, rtc->base + RZN1_RTC_HOUR); + writel(tm->tm_wday, rtc->base + RZN1_RTC_WEEK); + writel(tm->tm_mday, rtc->base + RZN1_RTC_DAY); + writel(tm->tm_mon, rtc->base + RZN1_RTC_MONTH); + writel(tm->tm_year, rtc->base + RZN1_RTC_YEAR); + writel(0, rtc->base + RZN1_RTC_CTL2); + + return 0; +} + +static const struct rtc_class_ops rzn1_rtc_ops = { + .read_time = rzn1_rtc_read_time, + .set_time = rzn1_rtc_set_time, +}; + +static int rzn1_rtc_probe(struct platform_device *pdev) +{ + struct rzn1_rtc *rtc; + int ret; + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + platform_set_drvdata(pdev, rtc); + + rtc->clk = devm_clk_get(&pdev->dev, "hclk"); + if (IS_ERR(rtc->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->clk), "Missing hclk\n"); + + rtc->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(rtc->base)) + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->base), "Missing reg\n"); + + rtc->rtcdev = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc->rtcdev)) + return PTR_ERR(rtc); + + rtc->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000; + rtc->rtcdev->range_max = RTC_TIMESTAMP_END_2099; + rtc->rtcdev->ops = &rzn1_rtc_ops; + clear_bit(RTC_FEATURE_ALARM, rtc->rtcdev->features); + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtcdev->features); + + ret = clk_prepare_enable(rtc->clk); + if (ret) + return ret; + + /* + * Ensure the clock counter is enabled. + * Set 24-hour mode and possible oscillator offset compensation in SUBU mode. + */ + writel(RZN1_RTC_CTL0_CE | RZN1_RTC_CTL0_AMPM | RZN1_RTC_CTL0_SLSB_SUBU, + rtc->base + RZN1_RTC_CTL0); + + /* Disable all interrupts */ + writel(0, rtc->base + RZN1_RTC_CTL1); + + ret = devm_rtc_register_device(rtc->rtcdev); + if (ret) + goto disable_clk; + + return 0; + +disable_clk: + clk_disable_unprepare(rtc->clk); + + return ret; +} + +static int rzn1_rtc_remove(struct platform_device *pdev) +{ + struct rzn1_rtc *rtc = platform_get_drvdata(pdev); + + clk_disable_unprepare(rtc->clk); + + return 0; +} + +static const struct of_device_id rzn1_rtc_of_match[] = { + { .compatible = "renesas,rzn1-rtc" }, + {}, +}; +MODULE_DEVICE_TABLE(of, rzn1_rtc_of_match); + +static struct platform_driver rzn1_rtc_driver = { + .probe = rzn1_rtc_probe, + .remove = rzn1_rtc_remove, + .driver = { + .name = "rzn1-rtc", + .owner = THIS_MODULE, + .of_match_table = rzn1_rtc_of_match, + }, +}; +module_platform_driver(rzn1_rtc_driver); + +MODULE_AUTHOR("Michel Pollet <Michel.Pollet@bp.renesas.com"); +MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com"); +MODULE_DESCRIPTION("RZ/N1 RTC driver"); +MODULE_LICENSE("GPL");