[PATCH v9 2/4] rtc: s32g: add NXP S32G2/S32G3 SoC support

Ciprian Marian Costea ciprianmarian.costea at oss.nxp.com
Wed Apr 9 07:58:19 PDT 2025


On 4/9/2025 5:42 PM, Enric Balletbo i Serra wrote:
> Hi Ciprian,
> 
> 
> On Wed, Apr 9, 2025 at 4:26 PM Ciprian Marian Costea
> <ciprianmarian.costea at oss.nxp.com> wrote:
>>
>> On 4/9/2025 5:14 PM, Enric Balletbo i Serra wrote:
>>> Hi Ciprian,
>>>
>>> Many thanks for your patch.
>>>
>>> On Thu, Apr 3, 2025 at 12:34 PM Ciprian Costea
>>> <ciprianmarian.costea at oss.nxp.com> wrote:
>>>>
>>>> From: Ciprian Marian Costea <ciprianmarian.costea at oss.nxp.com>
>>>>
>>>> Add a RTC driver for NXP S32G2/S32G3 SoCs.
>>>>
>>>> RTC tracks clock time during system suspend. It can be a wakeup source
>>>> for the S32G2/S32G3 SoC based boards.
>>>>
>>>> The RTC module from S32G2/S32G3 is not battery-powered and it is not kept
>>>> alive during system reset.
>>>>
>>>> Co-developed-by: Bogdan Hamciuc <bogdan.hamciuc at nxp.com>
>>>> Signed-off-by: Bogdan Hamciuc <bogdan.hamciuc at nxp.com>
>>>> Co-developed-by: Ghennadi Procopciuc <Ghennadi.Procopciuc at nxp.com>
>>>> Signed-off-by: Ghennadi Procopciuc <Ghennadi.Procopciuc at nxp.com>
>>>> Signed-off-by: Ciprian Marian Costea <ciprianmarian.costea at oss.nxp.com>
>>>> Reviewed-by: Frank Li <Frank.Li at nxp.com>
>>>
>>> I went through the code and it looks good to me, so:
>>>
>>> However, I did a basic rtctest selftest in my S32G-VNP-RDB3 board,
>>> and some tests failed (it shows a small deviation), any idea what
>>> could be wrong?
>>>
>>> This is the output of the test:
>>>
>>> # ./rtctest
>>> TAP version 13
>>> 1..8
>>> # Starting 8 tests from 1 test cases.
>>> #  RUN           rtc.date_read ...
>>> # rtctest.c:59:date_read:Current RTC date/time is 28/01/2025 00:17:49.
>>> #            OK  rtc.date_read
>>> ok 1 rtc.date_read
>>> #  RUN           rtc.date_read_loop ...
>>> # rtctest.c:124:date_read_loop:Continuously reading RTC time for 30s
>>> (with 11ms breaks after every read).
>>> # rtctest.c:151:date_read_loop:Performed 2638 RTC time reads.
>>> #            OK  rtc.date_read_loop
>>> ok 2 rtc.date_read_loop
>>> #  RUN           rtc.uie_read ...
>>> #            OK  rtc.uie_read
>>> ok 3 rtc.uie_read
>>> #  RUN           rtc.uie_select ...
>>> #            OK  rtc.uie_select
>>> ok 4 rtc.uie_select
>>> #  RUN           rtc.alarm_alm_set ...
>>> # rtctest.c:262:alarm_alm_set:Alarm time now set to 00:18:31.
>>> # rtctest.c:282:alarm_alm_set:data: 1a0
>>> #            OK  rtc.alarm_alm_set
>>> ok 5 rtc.alarm_alm_set
>>> #  RUN           rtc.alarm_wkalm_set ...
>>> # rtctest.c:334:alarm_wkalm_set:Alarm time now set to 28/01/2025 00:18:34.
>>> # rtctest.c:353:alarm_wkalm_set:Expected new (1738023515) == secs (1738023514)
>>> # alarm_wkalm_set: Test terminated by assertion
>>> #          FAIL  rtc.alarm_wkalm_set
>>> not ok 6 rtc.alarm_wkalm_set
>>> #  RUN           rtc.alarm_alm_set_minute ...
>>> # rtctest.c:394:alarm_alm_set_minute:Alarm time now set to 00:19:00.
>>> # rtctest.c:414:alarm_alm_set_minute:data: 1a0
>>> # rtctest.c:420:alarm_alm_set_minute:Expected new (1738023541) == secs
>>> (1738023540)
>>> # alarm_alm_set_minute: Test terminated by assertion
>>> #          FAIL  rtc.alarm_alm_set_minute
>>> not ok 7 rtc.alarm_alm_set_minute
>>> #  RUN           rtc.alarm_wkalm_set_minute ...
>>> # rtctest.c:464:alarm_wkalm_set_minute:Alarm time now set to
>>> 28/01/2025 00:20:00.
>>> # rtctest.c:483:alarm_wkalm_set_minute:Expected new (1738023601) ==
>>> secs (1738023600)
>>> # alarm_wkalm_set_minute: Test terminated by assertion
>>> #          FAIL  rtc.alarm_wkalm_set_minute
>>> not ok 8 rtc.alarm_wkalm_set_minute
>>> # FAILED: 5 / 8 tests passed.
>>> # Totals: pass:5 fail:3 xfail:0 xpass:0 skip:0 error:0
>>>
>>> Best regards,
>>>     Enric
>>>
>>
>> Hello Enric,
>>
>> In order to obtain a better resolution/precision you could try to only
>> use DIV512 hardware divisor instead of both DIV32 and DIV512.
>>
> 
> That makes the tests pass, so I'm wondering if by default you should
> set DIV512 in platform data instead. With that change you can add my
> 
> Tested-by: Enric Balletbo i Serra <eballetbo at kernel.org>
> 

This change would decrease the RTC rollover time. Initially indeed only 
DIV512 was enabled, but during review [1] I've agreed enabling both 
hardware divisors to increase the RTC rollover time. Personally, I am ok 
with the current 1 second resolution capability.

Alexandre Belloni, are you ok with the current version of this driver ? 
Or should I send a V10 patch in which I enable back only the DIV512 
divisor in order to increase the RTC precision at the downside of losing 
rollover time.

[1] 
https://lore.kernel.org/all/9f4fc9d8-ec7f-43b4-8bdd-01a4ba4855c5@oss.nxp.com/

Regards,
Ciprian

> # ./rtctest
> TAP version 13
> 1..8
> # Starting 8 tests from 1 test cases.
> #  RUN           rtc.date_read ...
> # rtctest.c:59:date_read:Current RTC date/time is 28/01/2025 00:00:34.
> #            OK  rtc.date_read
> ok 1 rtc.date_read
> #  RUN           rtc.date_read_loop ...
> # rtctest.c:124:date_read_loop:Continuously reading RTC time for 30s
> (with 11ms breaks after every read).
> # rtctest.c:151:date_read_loop:Performed 2656 RTC time reads.
> #            OK  rtc.date_read_loop
> ok 2 rtc.date_read_loop
> #  RUN           rtc.uie_read ...
> #            OK  rtc.uie_read
> ok 3 rtc.uie_read
> #  RUN           rtc.uie_select ...
> #            OK  rtc.uie_select
> ok 4 rtc.uie_select
> #  RUN           rtc.alarm_alm_set ...
> # rtctest.c:262:alarm_alm_set:Alarm time now set to 00:01:14.
> # rtctest.c:282:alarm_alm_set:data: 1a0
> #            OK  rtc.alarm_alm_set
> ok 5 rtc.alarm_alm_set
> #  RUN           rtc.alarm_wkalm_set ...
> # rtctest.c:334:alarm_wkalm_set:Alarm time now set to 28/01/2025 00:01:17.
> #            OK  rtc.alarm_wkalm_set
> ok 6 rtc.alarm_wkalm_set
> #  RUN           rtc.alarm_alm_set_minute ...
> # rtctest.c:394:alarm_alm_set_minute:Alarm time now set to 00:02:00.
> # rtctest.c:414:alarm_alm_set_minute:data: 1a0
> #            OK  rtc.alarm_alm_set_minute
> ok 7 rtc.alarm_alm_set_minute
> #  RUN           rtc.alarm_wkalm_set_minute ...
> # rtctest.c:464:alarm_wkalm_set_minute:Alarm time now set to
> 28/01/2025 00:03:00.
> #            OK  rtc.alarm_wkalm_set_minute
> ok 8 rtc.alarm_wkalm_set_minute
> # PASSED: 8 / 8 tests passed.
> # Totals: pass:8 fail:0 xfail:0 xpass:0 skip:0 error:0
> 
> 
> Thanks,
>   Enric
> 
>> Regards,
>> Ciprian
>>
>>>> ---
>>>>    drivers/rtc/Kconfig    |  11 ++
>>>>    drivers/rtc/Makefile   |   1 +
>>>>    drivers/rtc/rtc-s32g.c | 385 +++++++++++++++++++++++++++++++++++++++++
>>>>    3 files changed, 397 insertions(+)
>>>>    create mode 100644 drivers/rtc/rtc-s32g.c
>>>>
>>>> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
>>>> index 0bbbf778ecfa..510dc2db745d 100644
>>>> --- a/drivers/rtc/Kconfig
>>>> +++ b/drivers/rtc/Kconfig
>>>> @@ -2103,4 +2103,15 @@ config RTC_DRV_AMLOGIC_A4
>>>>             This driver can also be built as a module. If so, the module
>>>>             will be called "rtc-amlogic-a4".
>>>>
>>>> +config RTC_DRV_S32G
>>>> +       tristate "RTC driver for S32G2/S32G3 SoCs"
>>>> +       depends on ARCH_S32 || COMPILE_TEST
>>>> +       depends on COMMON_CLK
>>>> +       help
>>>> +         Say yes to enable RTC driver for platforms based on the
>>>> +         S32G2/S32G3 SoC family.
>>>> +
>>>> +         This RTC module can be used as a wakeup source.
>>>> +         Please note that it is not battery-powered.
>>>> +
>>>>    endif # RTC_CLASS
>>>> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
>>>> index 489b4ab07068..e4b616ecd5ce 100644
>>>> --- a/drivers/rtc/Makefile
>>>> +++ b/drivers/rtc/Makefile
>>>> @@ -161,6 +161,7 @@ obj-$(CONFIG_RTC_DRV_RX8111)        += rtc-rx8111.o
>>>>    obj-$(CONFIG_RTC_DRV_RX8581)   += rtc-rx8581.o
>>>>    obj-$(CONFIG_RTC_DRV_RZN1)     += rtc-rzn1.o
>>>>    obj-$(CONFIG_RTC_DRV_RENESAS_RTCA3)    += rtc-renesas-rtca3.o
>>>> +obj-$(CONFIG_RTC_DRV_S32G)     += rtc-s32g.o
>>>>    obj-$(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-s32g.c b/drivers/rtc/rtc-s32g.c
>>>> new file mode 100644
>>>> index 000000000000..3a0818e972eb
>>>> --- /dev/null
>>>> +++ b/drivers/rtc/rtc-s32g.c
>>>> @@ -0,0 +1,385 @@
>>>> +// SPDX-License-Identifier: GPL-2.0-or-later
>>>> +/*
>>>> + * Copyright 2025 NXP
>>>> + */
>>>> +
>>>> +#include <linux/bitfield.h>
>>>> +#include <linux/clk.h>
>>>> +#include <linux/iopoll.h>
>>>> +#include <linux/of_irq.h>
>>>> +#include <linux/platform_device.h>
>>>> +#include <linux/rtc.h>
>>>> +
>>>> +#define RTCC_OFFSET    0x4ul
>>>> +#define RTCS_OFFSET    0x8ul
>>>> +#define APIVAL_OFFSET  0x10ul
>>>> +
>>>> +/* RTCC fields */
>>>> +#define RTCC_CNTEN                             BIT(31)
>>>> +#define RTCC_APIEN                             BIT(15)
>>>> +#define RTCC_APIIE                             BIT(14)
>>>> +#define RTCC_CLKSEL_MASK               GENMASK(13, 12)
>>>> +#define RTCC_DIV512EN                  BIT(11)
>>>> +#define RTCC_DIV32EN                   BIT(10)
>>>> +
>>>> +/* RTCS fields */
>>>> +#define RTCS_INV_API   BIT(17)
>>>> +#define RTCS_APIF              BIT(13)
>>>> +
>>>> +#define APIVAL_MAX_VAL         GENMASK(31, 0)
>>>> +#define RTC_SYNCH_TIMEOUT      (100 * USEC_PER_MSEC)
>>>> +
>>>> +/*
>>>> + * S32G2 and S32G3 SoCs have RTC clock source1 reserved and
>>>> + * should not be used.
>>>> + */
>>>> +#define RTC_CLK_SRC1_RESERVED          BIT(1)
>>>> +
>>>> +/*
>>>> + * S32G RTC module has a 512 value and a 32 value hardware frequency
>>>> + * divisors (DIV512 and DIV32) which could be used to achieve higher
>>>> + * counter ranges by lowering the RTC frequency.
>>>> + */
>>>> +enum {
>>>> +       DIV1 = 1,
>>>> +       DIV32 = 32,
>>>> +       DIV512 = 512,
>>>> +       DIV512_32 = 16384
>>>> +};
>>>> +
>>>> +static const char *const rtc_clk_src[] = {
>>>> +       "source0",
>>>> +       "source1",
>>>> +       "source2",
>>>> +       "source3"
>>>> +};
>>>> +
>>>> +struct rtc_priv {
>>>> +       struct rtc_device *rdev;
>>>> +       void __iomem *rtc_base;
>>>> +       struct clk *ipg;
>>>> +       struct clk *clk_src;
>>>> +       const struct rtc_soc_data *rtc_data;
>>>> +       u64 rtc_hz;
>>>> +       time64_t sleep_sec;
>>>> +       int irq;
>>>> +       u32 clk_src_idx;
>>>> +};
>>>> +
>>>> +struct rtc_soc_data {
>>>> +       u32 clk_div;
>>>> +       u32 reserved_clk_mask;
>>>> +};
>>>> +
>>>> +static const struct rtc_soc_data rtc_s32g2_data = {
>>>> +       .clk_div = DIV512_32,
>>>> +       .reserved_clk_mask = RTC_CLK_SRC1_RESERVED,
>>>> +};
>>>> +
>>>> +static irqreturn_t s32g_rtc_handler(int irq, void *dev)
>>>> +{
>>>> +       struct rtc_priv *priv = platform_get_drvdata(dev);
>>>> +       u32 status;
>>>> +
>>>> +       status = readl(priv->rtc_base + RTCS_OFFSET);
>>>> +
>>>> +       if (status & RTCS_APIF) {
>>>> +               writel(0x0, priv->rtc_base + APIVAL_OFFSET);
>>>> +               writel(status | RTCS_APIF, priv->rtc_base + RTCS_OFFSET);
>>>> +       }
>>>> +
>>>> +       rtc_update_irq(priv->rdev, 1, RTC_IRQF | RTC_AF);
>>>> +
>>>> +       return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +/*
>>>> + * The function is not really getting time from the RTC since the S32G RTC
>>>> + * has several limitations. Thus, to setup alarm use system time.
>>>> + */
>>>> +static int s32g_rtc_read_time(struct device *dev,
>>>> +                             struct rtc_time *tm)
>>>> +{
>>>> +       struct rtc_priv *priv = dev_get_drvdata(dev);
>>>> +       time64_t sec;
>>>> +
>>>> +       if (check_add_overflow(ktime_get_real_seconds(),
>>>> +                              priv->sleep_sec, &sec))
>>>> +               return -ERANGE;
>>>> +
>>>> +       rtc_time64_to_tm(sec, tm);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +static int s32g_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
>>>> +{
>>>> +       struct rtc_priv *priv = dev_get_drvdata(dev);
>>>> +       u32 rtcc, rtcs;
>>>> +
>>>> +       rtcc = readl(priv->rtc_base + RTCC_OFFSET);
>>>> +       rtcs = readl(priv->rtc_base + RTCS_OFFSET);
>>>> +
>>>> +       alrm->enabled = rtcc & RTCC_APIIE;
>>>> +       if (alrm->enabled)
>>>> +               alrm->pending = !(rtcs & RTCS_APIF);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +static int s32g_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
>>>> +{
>>>> +       struct rtc_priv *priv = dev_get_drvdata(dev);
>>>> +       u32 rtcc;
>>>> +
>>>> +       /* RTC API functionality is used both for triggering interrupts
>>>> +        * and as a wakeup event. Hence it should always be enabled.
>>>> +        */
>>>> +       rtcc = readl(priv->rtc_base + RTCC_OFFSET);
>>>> +       rtcc |= RTCC_APIEN | RTCC_APIIE;
>>>> +       writel(rtcc, priv->rtc_base + RTCC_OFFSET);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +static int s32g_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
>>>> +{
>>>> +       struct rtc_priv *priv = dev_get_drvdata(dev);
>>>> +       unsigned long long cycles;
>>>> +       long long t_offset;
>>>> +       time64_t alrm_time;
>>>> +       u32 rtcs;
>>>> +       int ret;
>>>> +
>>>> +       alrm_time = rtc_tm_to_time64(&alrm->time);
>>>> +       t_offset = alrm_time - ktime_get_real_seconds() - priv->sleep_sec;
>>>> +       if (t_offset < 0)
>>>> +               return -ERANGE;
>>>> +
>>>> +       cycles = t_offset * priv->rtc_hz;
>>>> +       if (cycles > APIVAL_MAX_VAL)
>>>> +               return -ERANGE;
>>>> +
>>>> +       /* APIVAL could have been reset from the IRQ handler.
>>>> +        * Hence, we wait in case there is a synchronization process.
>>>> +        */
>>>> +       ret = read_poll_timeout(readl, rtcs, !(rtcs & RTCS_INV_API),
>>>> +                               0, RTC_SYNCH_TIMEOUT, false, priv->rtc_base + RTCS_OFFSET);
>>>> +       if (ret)
>>>> +               return ret;
>>>> +
>>>> +       writel(cycles, priv->rtc_base + APIVAL_OFFSET);
>>>> +
>>>> +       return read_poll_timeout(readl, rtcs, !(rtcs & RTCS_INV_API),
>>>> +                               0, RTC_SYNCH_TIMEOUT, false, priv->rtc_base + RTCS_OFFSET);
>>>> +}
>>>> +
>>>> +/*
>>>> + * Disable the 32-bit free running counter.
>>>> + * This allows Clock Source and Divisors selection
>>>> + * to be performed without causing synchronization issues.
>>>> + */
>>>> +static void s32g_rtc_disable(struct rtc_priv *priv)
>>>> +{
>>>> +       u32 rtcc = readl(priv->rtc_base + RTCC_OFFSET);
>>>> +
>>>> +       rtcc &= ~RTCC_CNTEN;
>>>> +       writel(rtcc, priv->rtc_base + RTCC_OFFSET);
>>>> +}
>>>> +
>>>> +static void s32g_rtc_enable(struct rtc_priv *priv)
>>>> +{
>>>> +       u32 rtcc = readl(priv->rtc_base + RTCC_OFFSET);
>>>> +
>>>> +       rtcc |= RTCC_CNTEN;
>>>> +       writel(rtcc, priv->rtc_base + RTCC_OFFSET);
>>>> +}
>>>> +
>>>> +static int rtc_clk_src_setup(struct rtc_priv *priv)
>>>> +{
>>>> +       u32 rtcc;
>>>> +
>>>> +       rtcc = FIELD_PREP(RTCC_CLKSEL_MASK, priv->clk_src_idx);
>>>> +
>>>> +       switch (priv->rtc_data->clk_div) {
>>>> +       case DIV512_32:
>>>> +               rtcc |= RTCC_DIV512EN;
>>>> +               rtcc |= RTCC_DIV32EN;
>>>> +               break;
>>>> +       case DIV512:
>>>> +               rtcc |= RTCC_DIV512EN;
>>>> +               break;
>>>> +       case DIV32:
>>>> +               rtcc |= RTCC_DIV32EN;
>>>> +               break;
>>>> +       case DIV1:
>>>> +               break;
>>>> +       default:
>>>> +               return -EINVAL;
>>>> +       }
>>>> +
>>>> +       rtcc |= RTCC_APIEN | RTCC_APIIE;
>>>> +       /*
>>>> +        * Make sure the CNTEN is 0 before we configure
>>>> +        * the clock source and dividers.
>>>> +        */
>>>> +       s32g_rtc_disable(priv);
>>>> +       writel(rtcc, priv->rtc_base + RTCC_OFFSET);
>>>> +       s32g_rtc_enable(priv);
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +static const struct rtc_class_ops rtc_ops = {
>>>> +       .read_time = s32g_rtc_read_time,
>>>> +       .read_alarm = s32g_rtc_read_alarm,
>>>> +       .set_alarm = s32g_rtc_set_alarm,
>>>> +       .alarm_irq_enable = s32g_rtc_alarm_irq_enable,
>>>> +};
>>>> +
>>>> +static int rtc_clk_dts_setup(struct rtc_priv *priv,
>>>> +                            struct device *dev)
>>>> +{
>>>> +       u32 i;
>>>> +
>>>> +       priv->ipg = devm_clk_get_enabled(dev, "ipg");
>>>> +       if (IS_ERR(priv->ipg))
>>>> +               return dev_err_probe(dev, PTR_ERR(priv->ipg),
>>>> +                               "Failed to get 'ipg' clock\n");
>>>> +
>>>> +       for (i = 0; i < ARRAY_SIZE(rtc_clk_src); i++) {
>>>> +               if (priv->rtc_data->reserved_clk_mask & BIT(i))
>>>> +                       return -EOPNOTSUPP;
>>>> +
>>>> +               priv->clk_src = devm_clk_get_enabled(dev, rtc_clk_src[i]);
>>>> +               if (!IS_ERR(priv->clk_src)) {
>>>> +                       priv->clk_src_idx = i;
>>>> +                       break;
>>>> +               }
>>>> +       }
>>>> +
>>>> +       if (IS_ERR(priv->clk_src))
>>>> +               return dev_err_probe(dev, PTR_ERR(priv->clk_src),
>>>> +                               "Failed to get rtc module clock source\n");
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +static int s32g_rtc_probe(struct platform_device *pdev)
>>>> +{
>>>> +       struct device *dev = &pdev->dev;
>>>> +       struct rtc_priv *priv;
>>>> +       unsigned long rtc_hz;
>>>> +       int ret;
>>>> +
>>>> +       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>>>> +       if (!priv)
>>>> +               return -ENOMEM;
>>>> +
>>>> +       priv->rtc_data = of_device_get_match_data(dev);
>>>> +       if (!priv->rtc_data)
>>>> +               return -ENODEV;
>>>> +
>>>> +       priv->rtc_base = devm_platform_ioremap_resource(pdev, 0);
>>>> +       if (IS_ERR(priv->rtc_base))
>>>> +               return PTR_ERR(priv->rtc_base);
>>>> +
>>>> +       device_init_wakeup(dev, true);
>>>> +
>>>> +       ret = rtc_clk_dts_setup(priv, dev);
>>>> +       if (ret)
>>>> +               return ret;
>>>> +
>>>> +       priv->rdev = devm_rtc_allocate_device(dev);
>>>> +       if (IS_ERR(priv->rdev))
>>>> +               return PTR_ERR(priv->rdev);
>>>> +
>>>> +       ret = rtc_clk_src_setup(priv);
>>>> +       if (ret)
>>>> +               return ret;
>>>> +
>>>> +       priv->irq = platform_get_irq(pdev, 0);
>>>> +       if (priv->irq < 0) {
>>>> +               ret = priv->irq;
>>>> +               goto disable_rtc;
>>>> +       }
>>>> +
>>>> +       rtc_hz = clk_get_rate(priv->clk_src);
>>>> +       if (!rtc_hz) {
>>>> +               dev_err(dev, "Failed to get RTC frequency\n");
>>>> +               ret = -EINVAL;
>>>> +               goto disable_rtc;
>>>> +       }
>>>> +
>>>> +       priv->rtc_hz = DIV_ROUND_UP(rtc_hz, priv->rtc_data->clk_div);
>>>> +
>>>> +       platform_set_drvdata(pdev, priv);
>>>> +       priv->rdev->ops = &rtc_ops;
>>>> +
>>>> +       ret = devm_request_irq(dev, priv->irq,
>>>> +                              s32g_rtc_handler, 0, dev_name(dev), pdev);
>>>> +       if (ret) {
>>>> +               dev_err(dev, "Request interrupt %d failed, error: %d\n",
>>>> +                       priv->irq, ret);
>>>> +               goto disable_rtc;
>>>> +       }
>>>> +
>>>> +       ret = devm_rtc_register_device(priv->rdev);
>>>> +       if (ret)
>>>> +               goto disable_rtc;
>>>> +
>>>> +       return 0;
>>>> +
>>>> +disable_rtc:
>>>> +       s32g_rtc_disable(priv);
>>>> +       return ret;
>>>> +}
>>>> +
>>>> +static int s32g_rtc_suspend(struct device *dev)
>>>> +{
>>>> +       struct rtc_priv *priv = dev_get_drvdata(dev);
>>>> +       u32 apival = readl(priv->rtc_base + APIVAL_OFFSET);
>>>> +
>>>> +       if (check_add_overflow(priv->sleep_sec, div64_u64(apival, priv->rtc_hz),
>>>> +                              &priv->sleep_sec)) {
>>>> +               dev_warn(dev, "Overflow on sleep cycles occurred. Resetting to 0.\n");
>>>> +               priv->sleep_sec = 0;
>>>> +       }
>>>> +
>>>> +       return 0;
>>>> +}
>>>> +
>>>> +static int s32g_rtc_resume(struct device *dev)
>>>> +{
>>>> +       struct rtc_priv *priv = dev_get_drvdata(dev);
>>>> +
>>>> +       /* The transition from resume to run is a reset event.
>>>> +        * This leads to the RTC registers being reset after resume from
>>>> +        * suspend. It is uncommon, but this behaviour has been observed
>>>> +        * on S32G RTC after issuing a Suspend to RAM operation.
>>>> +        * Thus, reconfigure RTC registers on the resume path.
>>>> +        */
>>>> +       return rtc_clk_src_setup(priv);
>>>> +}
>>>> +
>>>> +static const struct of_device_id rtc_dt_ids[] = {
>>>> +       { .compatible = "nxp,s32g2-rtc", .data = &rtc_s32g2_data },
>>>> +       { /* sentinel */ },
>>>> +};
>>>> +
>>>> +static DEFINE_SIMPLE_DEV_PM_OPS(s32g_rtc_pm_ops,
>>>> +                        s32g_rtc_suspend, s32g_rtc_resume);
>>>> +
>>>> +static struct platform_driver s32g_rtc_driver = {
>>>> +       .driver = {
>>>> +               .name = "s32g-rtc",
>>>> +               .pm = pm_sleep_ptr(&s32g_rtc_pm_ops),
>>>> +               .of_match_table = rtc_dt_ids,
>>>> +       },
>>>> +       .probe = s32g_rtc_probe,
>>>> +};
>>>> +module_platform_driver(s32g_rtc_driver);
>>>> +
>>>> +MODULE_AUTHOR("NXP");
>>>> +MODULE_DESCRIPTION("NXP RTC driver for S32G2/S32G3");
>>>> +MODULE_LICENSE("GPL");
>>>> --
>>>> 2.45.2
>>>>
>>>
>>
> 




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