| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Andrew Chew | 1263 | 76.22% | 1 | 4.17% |
| Thierry Reding | 240 | 14.48% | 7 | 29.17% |
| Alexandre Belloni | 63 | 3.80% | 3 | 12.50% |
| Laxman Dewangan | 31 | 1.87% | 3 | 12.50% |
| Joseph Lo | 28 | 1.69% | 1 | 4.17% |
| Hannu Heikkinen | 17 | 1.03% | 1 | 4.17% |
| Joe Perches | 3 | 0.18% | 1 | 4.17% |
| Randy Dunlap | 3 | 0.18% | 1 | 4.17% |
| Uwe Kleine-König | 2 | 0.12% | 1 | 4.17% |
| Xiaofei Tan | 2 | 0.12% | 1 | 4.17% |
| Yue haibing | 2 | 0.12% | 1 | 4.17% |
| Andy Shevchenko | 1 | 0.06% | 1 | 4.17% |
| Bartosz Golaszewski | 1 | 0.06% | 1 | 4.17% |
| Julia Lawall | 1 | 0.06% | 1 | 4.17% |
| Total | 1657 | 24 |
// SPDX-License-Identifier: GPL-2.0+ /* * An RTC driver for the NVIDIA Tegra 200 series internal RTC. * * Copyright (c) 2010-2019, NVIDIA Corporation. */ #include <linux/clk.h> #include <linux/delay.h> #include <linux/init.h> #include <linux/io.h> #include <linux/irq.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/platform_device.h> #include <linux/pm.h> #include <linux/rtc.h> #include <linux/slab.h> /* Set to 1 = busy every eight 32 kHz clocks during copy of sec+msec to AHB. */ #define TEGRA_RTC_REG_BUSY 0x004 #define TEGRA_RTC_REG_SECONDS 0x008 /* When msec is read, the seconds are buffered into shadow seconds. */ #define TEGRA_RTC_REG_SHADOW_SECONDS 0x00c #define TEGRA_RTC_REG_MILLI_SECONDS 0x010 #define TEGRA_RTC_REG_SECONDS_ALARM0 0x014 #define TEGRA_RTC_REG_SECONDS_ALARM1 0x018 #define TEGRA_RTC_REG_MILLI_SECONDS_ALARM0 0x01c #define TEGRA_RTC_REG_INTR_MASK 0x028 /* write 1 bits to clear status bits */ #define TEGRA_RTC_REG_INTR_STATUS 0x02c /* bits in INTR_MASK */ #define TEGRA_RTC_INTR_MASK_MSEC_CDN_ALARM (1<<4) #define TEGRA_RTC_INTR_MASK_SEC_CDN_ALARM (1<<3) #define TEGRA_RTC_INTR_MASK_MSEC_ALARM (1<<2) #define TEGRA_RTC_INTR_MASK_SEC_ALARM1 (1<<1) #define TEGRA_RTC_INTR_MASK_SEC_ALARM0 (1<<0) /* bits in INTR_STATUS */ #define TEGRA_RTC_INTR_STATUS_MSEC_CDN_ALARM (1<<4) #define TEGRA_RTC_INTR_STATUS_SEC_CDN_ALARM (1<<3) #define TEGRA_RTC_INTR_STATUS_MSEC_ALARM (1<<2) #define TEGRA_RTC_INTR_STATUS_SEC_ALARM1 (1<<1) #define TEGRA_RTC_INTR_STATUS_SEC_ALARM0 (1<<0) struct tegra_rtc_info { struct platform_device *pdev; struct rtc_device *rtc; void __iomem *base; /* NULL if not initialized */ struct clk *clk; int irq; /* alarm and periodic IRQ */ spinlock_t lock; }; /* * RTC hardware is busy when it is updating its values over AHB once every * eight 32 kHz clocks (~250 us). Outside of these updates the CPU is free to * write. CPU is always free to read. */ static inline u32 tegra_rtc_check_busy(struct tegra_rtc_info *info) { return readl(info->base + TEGRA_RTC_REG_BUSY) & 1; } /* * Wait for hardware to be ready for writing. This function tries to maximize * the amount of time before the next update. It does this by waiting for the * RTC to become busy with its periodic update, then returning once the RTC * first becomes not busy. * * This periodic update (where the seconds and milliseconds are copied to the * AHB side) occurs every eight 32 kHz clocks (~250 us). The behavior of this * function allows us to make some assumptions without introducing a race, * because 250 us is plenty of time to read/write a value. */ static int tegra_rtc_wait_while_busy(struct device *dev) { struct tegra_rtc_info *info = dev_get_drvdata(dev); int retries = 500; /* ~490 us is the worst case, ~250 us is best */ /* * First wait for the RTC to become busy. This is when it posts its * updated seconds+msec registers to AHB side. */ while (tegra_rtc_check_busy(info)) { if (!retries--) goto retry_failed; udelay(1); } /* now we have about 250 us to manipulate registers */ return 0; retry_failed: dev_err(dev, "write failed: retry count exceeded\n"); return -ETIMEDOUT; } static int tegra_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct tegra_rtc_info *info = dev_get_drvdata(dev); unsigned long flags; u32 sec; /* * RTC hardware copies seconds to shadow seconds when a read of * milliseconds occurs. use a lock to keep other threads out. */ spin_lock_irqsave(&info->lock, flags); readl(info->base + TEGRA_RTC_REG_MILLI_SECONDS); sec = readl(info->base + TEGRA_RTC_REG_SHADOW_SECONDS); spin_unlock_irqrestore(&info->lock, flags); rtc_time64_to_tm(sec, tm); dev_vdbg(dev, "time read as %u, %ptR\n", sec, tm); return 0; } static int tegra_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct tegra_rtc_info *info = dev_get_drvdata(dev); u32 sec; int ret; /* convert tm to seconds */ sec = rtc_tm_to_time64(tm); dev_vdbg(dev, "time set to %u, %ptR\n", sec, tm); /* seconds only written if wait succeeded */ ret = tegra_rtc_wait_while_busy(dev); if (!ret) writel(sec, info->base + TEGRA_RTC_REG_SECONDS); dev_vdbg(dev, "time read back as %d\n", readl(info->base + TEGRA_RTC_REG_SECONDS)); return ret; } static int tegra_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) { struct tegra_rtc_info *info = dev_get_drvdata(dev); u32 sec, value; sec = readl(info->base + TEGRA_RTC_REG_SECONDS_ALARM0); if (sec == 0) { /* alarm is disabled */ alarm->enabled = 0; } else { /* alarm is enabled */ alarm->enabled = 1; rtc_time64_to_tm(sec, &alarm->time); } value = readl(info->base + TEGRA_RTC_REG_INTR_STATUS); alarm->pending = (value & TEGRA_RTC_INTR_STATUS_SEC_ALARM0) != 0; return 0; } static int tegra_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct tegra_rtc_info *info = dev_get_drvdata(dev); unsigned long flags; u32 status; tegra_rtc_wait_while_busy(dev); spin_lock_irqsave(&info->lock, flags); /* read the original value, and OR in the flag */ status = readl(info->base + TEGRA_RTC_REG_INTR_MASK); if (enabled) status |= TEGRA_RTC_INTR_MASK_SEC_ALARM0; /* set it */ else status &= ~TEGRA_RTC_INTR_MASK_SEC_ALARM0; /* clear it */ writel(status, info->base + TEGRA_RTC_REG_INTR_MASK); spin_unlock_irqrestore(&info->lock, flags); return 0; } static int tegra_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) { struct tegra_rtc_info *info = dev_get_drvdata(dev); u32 sec; if (alarm->enabled) sec = rtc_tm_to_time64(&alarm->time); else sec = 0; tegra_rtc_wait_while_busy(dev); writel(sec, info->base + TEGRA_RTC_REG_SECONDS_ALARM0); dev_vdbg(dev, "alarm read back as %d\n", readl(info->base + TEGRA_RTC_REG_SECONDS_ALARM0)); /* if successfully written and alarm is enabled ... */ if (sec) { tegra_rtc_alarm_irq_enable(dev, 1); dev_vdbg(dev, "alarm set as %u, %ptR\n", sec, &alarm->time); } else { /* disable alarm if 0 or write error */ dev_vdbg(dev, "alarm disabled\n"); tegra_rtc_alarm_irq_enable(dev, 0); } return 0; } static int tegra_rtc_proc(struct device *dev, struct seq_file *seq) { if (!dev || !dev->driver) return 0; seq_printf(seq, "name\t\t: %s\n", dev_name(dev)); return 0; } static irqreturn_t tegra_rtc_irq_handler(int irq, void *data) { struct device *dev = data; struct tegra_rtc_info *info = dev_get_drvdata(dev); unsigned long events = 0; u32 status; status = readl(info->base + TEGRA_RTC_REG_INTR_STATUS); if (status) { /* clear the interrupt masks and status on any IRQ */ tegra_rtc_wait_while_busy(dev); spin_lock(&info->lock); writel(0, info->base + TEGRA_RTC_REG_INTR_MASK); writel(status, info->base + TEGRA_RTC_REG_INTR_STATUS); spin_unlock(&info->lock); } /* check if alarm */ if (status & TEGRA_RTC_INTR_STATUS_SEC_ALARM0) events |= RTC_IRQF | RTC_AF; /* check if periodic */ if (status & TEGRA_RTC_INTR_STATUS_SEC_CDN_ALARM) events |= RTC_IRQF | RTC_PF; rtc_update_irq(info->rtc, 1, events); return IRQ_HANDLED; } static const struct rtc_class_ops tegra_rtc_ops = { .read_time = tegra_rtc_read_time, .set_time = tegra_rtc_set_time, .read_alarm = tegra_rtc_read_alarm, .set_alarm = tegra_rtc_set_alarm, .proc = tegra_rtc_proc, .alarm_irq_enable = tegra_rtc_alarm_irq_enable, }; static const struct of_device_id tegra_rtc_dt_match[] = { { .compatible = "nvidia,tegra20-rtc", }, {} }; MODULE_DEVICE_TABLE(of, tegra_rtc_dt_match); static int tegra_rtc_probe(struct platform_device *pdev) { struct tegra_rtc_info *info; int ret; info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); if (!info) return -ENOMEM; info->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(info->base)) return PTR_ERR(info->base); ret = platform_get_irq(pdev, 0); if (ret <= 0) return ret; info->irq = ret; info->rtc = devm_rtc_allocate_device(&pdev->dev); if (IS_ERR(info->rtc)) return PTR_ERR(info->rtc); info->rtc->ops = &tegra_rtc_ops; info->rtc->range_max = U32_MAX; info->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(info->clk)) return PTR_ERR(info->clk); ret = clk_prepare_enable(info->clk); if (ret < 0) return ret; /* set context info */ info->pdev = pdev; spin_lock_init(&info->lock); platform_set_drvdata(pdev, info); /* clear out the hardware */ writel(0, info->base + TEGRA_RTC_REG_SECONDS_ALARM0); writel(0xffffffff, info->base + TEGRA_RTC_REG_INTR_STATUS); writel(0, info->base + TEGRA_RTC_REG_INTR_MASK); device_init_wakeup(&pdev->dev, 1); ret = devm_request_irq(&pdev->dev, info->irq, tegra_rtc_irq_handler, IRQF_TRIGGER_HIGH, dev_name(&pdev->dev), &pdev->dev); if (ret) { dev_err(&pdev->dev, "failed to request interrupt: %d\n", ret); goto disable_clk; } ret = devm_rtc_register_device(info->rtc); if (ret) goto disable_clk; dev_notice(&pdev->dev, "Tegra internal Real Time Clock\n"); return 0; disable_clk: clk_disable_unprepare(info->clk); return ret; } static int tegra_rtc_remove(struct platform_device *pdev) { struct tegra_rtc_info *info = platform_get_drvdata(pdev); clk_disable_unprepare(info->clk); return 0; } #ifdef CONFIG_PM_SLEEP static int tegra_rtc_suspend(struct device *dev) { struct tegra_rtc_info *info = dev_get_drvdata(dev); tegra_rtc_wait_while_busy(dev); /* only use ALARM0 as a wake source */ writel(0xffffffff, info->base + TEGRA_RTC_REG_INTR_STATUS); writel(TEGRA_RTC_INTR_STATUS_SEC_ALARM0, info->base + TEGRA_RTC_REG_INTR_MASK); dev_vdbg(dev, "alarm sec = %d\n", readl(info->base + TEGRA_RTC_REG_SECONDS_ALARM0)); dev_vdbg(dev, "Suspend (device_may_wakeup=%d) IRQ:%d\n", device_may_wakeup(dev), info->irq); /* leave the alarms on as a wake source */ if (device_may_wakeup(dev)) enable_irq_wake(info->irq); return 0; } static int tegra_rtc_resume(struct device *dev) { struct tegra_rtc_info *info = dev_get_drvdata(dev); dev_vdbg(dev, "Resume (device_may_wakeup=%d)\n", device_may_wakeup(dev)); /* alarms were left on as a wake source, turn them off */ if (device_may_wakeup(dev)) disable_irq_wake(info->irq); return 0; } #endif static SIMPLE_DEV_PM_OPS(tegra_rtc_pm_ops, tegra_rtc_suspend, tegra_rtc_resume); static void tegra_rtc_shutdown(struct platform_device *pdev) { dev_vdbg(&pdev->dev, "disabling interrupts\n"); tegra_rtc_alarm_irq_enable(&pdev->dev, 0); } static struct platform_driver tegra_rtc_driver = { .probe = tegra_rtc_probe, .remove = tegra_rtc_remove, .shutdown = tegra_rtc_shutdown, .driver = { .name = "tegra_rtc", .of_match_table = tegra_rtc_dt_match, .pm = &tegra_rtc_pm_ops, }, }; module_platform_driver(tegra_rtc_driver); MODULE_AUTHOR("Jon Mayo <jmayo@nvidia.com>"); MODULE_DESCRIPTION("driver for Tegra internal RTC"); MODULE_LICENSE("GPL");
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