ASR_BASE

Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/rtc/rtc-sa1100.c b/marvell/linux/drivers/rtc/rtc-sa1100.c
new file mode 100644
index 0000000..b702dbe
--- /dev/null
+++ b/marvell/linux/drivers/rtc/rtc-sa1100.c
@@ -0,0 +1,428 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Real Time Clock interface for StrongARM SA1x00 and XScale PXA2xx
+ *
+ * Copyright (c) 2000 Nils Faerber
+ *
+ * Based on rtc.c by Paul Gortmaker
+ *
+ * Original Driver by Nils Faerber <nils@kernelconcepts.de>
+ *
+ * Modifications from:
+ *   CIH <cih@coventive.com>
+ *   Nicolas Pitre <nico@fluxnic.net>
+ *   Andrew Christian <andrew.christian@hp.com>
+ *
+ * Converted to the RTC subsystem and Driver Model
+ *   by Richard Purdie <rpurdie@rpsys.net>
+ */
+
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/clk.h>
+#include <linux/rtc.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/cputype.h>
+
+#define RCNR		0x00	/* RTC Count Register */
+#define RTAR		0x04	/* RTC Alarm Register */
+#define RTSR		0x08	/* RTC Status Register */
+#define RTTR		0x0C	/* RTC Timer Trim Register */
+#define RTSR_HZE		BIT(3)	/* HZ interrupt enable */
+#define RTSR_ALE		BIT(2)	/* RTC alarm interrupt enable */
+#define RTSR_HZ			BIT(1)	/* HZ rising-edge detected */
+#define RTSR_AL			BIT(0)	/* RTC alarm detected */
+
+#include "rtc-sa1100.h"
+
+#define RTC_DEF_DIVIDER		(32768 - 1)
+
+#ifdef CONFIG_CPU_ASR1903
+#define SCS_RTC_DEF_DIVIDER	 (32765 - 1)
+#else
+#define SCS_RTC_DEF_DIVIDER	 (32787 - 1)
+#endif
+
+#define RTC_DEF_TRIM		0
+#define RTC_FREQ		1024
+
+static s64 base_ticks;
+
+static void __iomem		*rtc_reg_base;
+int sync_time_to_soc(s64 ticks)
+{
+	s64 cur_ticks;
+
+	if (rtc_reg_base) {
+		cur_ticks = readl(rtc_reg_base + RCNR); 
+		base_ticks = ticks - cur_ticks;
+		pr_info("sync ticks: %lld %lld %lld\n",
+			ticks, cur_ticks, base_ticks);
+#if 0
+		writel(ticks, rtc_reg_base + RCNR);
+		/*
+		 * for soc rtc time setting, it needs some delay
+		 * to ensure setting to take effective
+		 */
+		udelay(200);
+#endif
+	}
+	return 0;
+}
+EXPORT_SYMBOL(sync_time_to_soc);
+
+static irqreturn_t sa1100_rtc_interrupt(int irq, void *dev_id)
+{
+	struct sa1100_rtc *info = dev_get_drvdata(dev_id);
+	struct rtc_device *rtc = info->rtc;
+	unsigned int rtsr;
+	unsigned long events = 0;
+
+	spin_lock(&info->lock);
+
+	rtsr = readl_relaxed(info->rtsr);
+	/* clear interrupt sources */
+	writel_relaxed(0, info->rtsr);
+	/* Fix for a nasty initialization problem the in SA11xx RTSR register.
+	 * See also the comments in sa1100_rtc_probe(). */
+	if (rtsr & (RTSR_ALE | RTSR_HZE)) {
+		/* This is the original code, before there was the if test
+		 * above. This code does not clear interrupts that were not
+		 * enabled. */
+		writel_relaxed((RTSR_AL | RTSR_HZ) & (rtsr >> 2), info->rtsr);
+	} else {
+		/* For some reason, it is possible to enter this routine
+		 * without interruptions enabled, it has been tested with
+		 * several units (Bug in SA11xx chip?).
+		 *
+		 * This situation leads to an infinite "loop" of interrupt
+		 * routine calling and as a result the processor seems to
+		 * lock on its first call to open(). */
+		writel_relaxed(RTSR_AL | RTSR_HZ, info->rtsr);
+	}
+
+	/* clear alarm interrupt if it has occurred */
+	if (rtsr & RTSR_AL)
+		rtsr &= ~RTSR_ALE;
+	writel_relaxed(rtsr & (RTSR_ALE | RTSR_HZE), info->rtsr);
+
+	/* update irq data & counter */
+	if (rtsr & RTSR_AL)
+		events |= RTC_AF | RTC_IRQF;
+	if (rtsr & RTSR_HZ)
+		events |= RTC_UF | RTC_IRQF;
+
+	rtc_update_irq(rtc, 1, events);
+
+	spin_unlock(&info->lock);
+
+	return IRQ_HANDLED;
+}
+
+static int sa1100_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	u32 rtsr;
+	unsigned long flags;
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+
+	spin_lock_irqsave(&info->lock, flags);
+	rtsr = readl_relaxed(info->rtsr);
+	if (enabled)
+		rtsr |= RTSR_ALE;
+	else
+		rtsr &= ~RTSR_ALE;
+	writel_relaxed(rtsr, info->rtsr);
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+static int sa1100_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	s64 ticks;
+
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+
+	ticks = readl_relaxed(info->rcnr) + base_ticks;
+	rtc_time64_to_tm(ticks, tm);
+	return 0;
+}
+
+static int sa1100_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+	s64 ticks;
+
+	/* to align with rtc-88pm80x/scs */
+	if ((tm->tm_year < 70) || (tm->tm_year > 300)) {
+		pr_err("SCSRTC: Set time %d out of range. Please set time between 1970 to 2200.\n",
+			1900 + tm->tm_year);
+		return -EINVAL;
+	}
+
+	ticks = rtc_tm_to_time64(tm);
+	ticks = ticks - base_ticks;
+	BUG_ON(ticks < 0);
+	writel_relaxed((u32)ticks, info->rcnr);
+	/* stabilize the register value */
+	udelay(200);
+	return 0;
+}
+
+static int sa1100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	u32	rtsr;
+	s64 time;
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+
+	time = base_ticks + readl_relaxed(info->rtar);
+	rtc_time64_to_tm(time,  &alrm->time);
+	rtsr = readl_relaxed(info->rtsr);
+	alrm->enabled = (rtsr & RTSR_ALE) ? 1 : 0;
+	alrm->pending = (rtsr & RTSR_AL) ? 1 : 0;
+	return 0;
+}
+
+static int sa1100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+	s64 time;
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	time = rtc_tm_to_time64(&alrm->time);
+	writel_relaxed(readl_relaxed(info->rtsr) &
+		(RTSR_HZE | RTSR_ALE | RTSR_AL), info->rtsr);
+	time = time - base_ticks;
+	writel_relaxed((u32)time, info->rtar);
+	BUG_ON(time < 0);
+	if (alrm->enabled)
+		writel_relaxed(readl_relaxed(info->rtsr) | RTSR_ALE, info->rtsr);
+	else
+		writel_relaxed(readl_relaxed(info->rtsr) & ~RTSR_ALE, info->rtsr);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	return ret;
+}
+
+static int sa1100_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+
+	seq_printf(seq, "trim/divider\t\t: 0x%08x\n", readl_relaxed(info->rttr));
+	seq_printf(seq, "RTSR\t\t\t: 0x%08x\n", readl_relaxed(info->rtsr));
+
+	return 0;
+}
+
+static const struct rtc_class_ops sa1100_rtc_ops = {
+	.read_time = sa1100_rtc_read_time,
+	.set_time = sa1100_rtc_set_time,
+	.read_alarm = sa1100_rtc_read_alarm,
+	.set_alarm = sa1100_rtc_set_alarm,
+	.proc = sa1100_rtc_proc,
+	.alarm_irq_enable = sa1100_rtc_alarm_irq_enable,
+};
+
+int sa1100_rtc_init(struct platform_device *pdev, struct sa1100_rtc *info)
+{
+	int ret;
+
+	spin_lock_init(&info->lock);
+
+	info->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(info->clk)) {
+		dev_err(&pdev->dev, "failed to find rtc clock source\n");
+		return PTR_ERR(info->clk);
+	}
+
+	ret = clk_prepare_enable(info->clk);
+	if (ret)
+		return ret;
+	/*
+	 * According to the manual we should be able to let RTTR be zero
+	 * and then a default diviser for a 32.768KHz clock is used.
+	 * Apparently this doesn't work, at least for my SA1110 rev 5.
+	 * If the clock divider is uninitialized then reset it to the
+	 * default value to get the 1Hz clock.
+	 */
+	if (readl_relaxed(info->rttr) == 0) {
+		writel_relaxed(RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16), info->rttr);
+		dev_warn(&pdev->dev, "warning: "
+			"initializing default clock divider/trim value\n");
+		/* The current RTC value probably doesn't make sense either */
+		writel_relaxed(0, info->rcnr);
+	} else if (cpu_is_asr1803() || cpu_is_asr1806()) {
+		writel_relaxed(SCS_RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16), info->rttr);
+	}
+
+	info->rtc->ops = &sa1100_rtc_ops;
+	info->rtc->max_user_freq = RTC_FREQ;
+
+	ret = rtc_register_device(info->rtc);
+	if (ret) {
+		clk_disable_unprepare(info->clk);
+		return ret;
+	}
+
+	/* Fix for a nasty initialization problem the in SA11xx RTSR register.
+	 * See also the comments in sa1100_rtc_interrupt().
+	 *
+	 * Sometimes bit 1 of the RTSR (RTSR_HZ) will wake up 1, which means an
+	 * interrupt pending, even though interrupts were never enabled.
+	 * In this case, this bit it must be reset before enabling
+	 * interruptions to avoid a nonexistent interrupt to occur.
+	 *
+	 * In principle, the same problem would apply to bit 0, although it has
+	 * never been observed to happen.
+	 *
+	 * This issue is addressed both here and in sa1100_rtc_interrupt().
+	 * If the issue is not addressed here, in the times when the processor
+	 * wakes up with the bit set there will be one spurious interrupt.
+	 *
+	 * The issue is also dealt with in sa1100_rtc_interrupt() to be on the
+	 * safe side, once the condition that lead to this strange
+	 * initialization is unknown and could in principle happen during
+	 * normal processing.
+	 *
+	 * Notice that clearing bit 1 and 0 is accomplished by writting ONES to
+	 * the corresponding bits in RTSR. */
+	writel_relaxed(RTSR_AL | RTSR_HZ, info->rtsr);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sa1100_rtc_init);
+
+static int sa1100_rtc_probe(struct platform_device *pdev)
+{
+	struct sa1100_rtc *info;
+	struct resource *iores;
+	void __iomem *base;
+	int irq_1hz, irq_alarm;
+	int ret;
+
+	irq_1hz = platform_get_irq_byname(pdev, "rtc 1Hz");
+	irq_alarm = platform_get_irq_byname(pdev, "rtc alarm");
+	if (irq_1hz < 0 || irq_alarm < 0)
+		return -ENODEV;
+
+	info = devm_kzalloc(&pdev->dev, sizeof(struct sa1100_rtc), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+	info->irq_1hz = irq_1hz;
+	info->irq_alarm = irq_alarm;
+
+	info->rtc = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(info->rtc))
+		return PTR_ERR(info->rtc);
+
+	ret = devm_request_irq(&pdev->dev, irq_1hz, sa1100_rtc_interrupt, 0,
+			       "rtc 1Hz", &pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "IRQ %d already in use.\n", irq_1hz);
+		return ret;
+	}
+	ret = devm_request_irq(&pdev->dev, irq_alarm, sa1100_rtc_interrupt, 0,
+			       "rtc Alrm", &pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "IRQ %d already in use.\n", irq_alarm);
+		return ret;
+	}
+
+	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, iores);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+	rtc_reg_base = base;
+
+	if (IS_ENABLED(CONFIG_ARCH_SA1100) ||
+	    of_device_is_compatible(pdev->dev.of_node, "mrvl,sa1100-rtc")) {
+		info->rcnr = base + 0x04;
+		info->rtsr = base + 0x10;
+		info->rtar = base + 0x00;
+		info->rttr = base + 0x08;
+	} else {
+		info->rcnr = base + 0x0;
+		info->rtsr = base + 0x8;
+		info->rtar = base + 0x4;
+		info->rttr = base + 0xc;
+	}
+
+	platform_set_drvdata(pdev, info);
+	device_init_wakeup(&pdev->dev, 1);
+
+	return sa1100_rtc_init(pdev, info);
+}
+
+static int sa1100_rtc_remove(struct platform_device *pdev)
+{
+	unsigned long flags;
+	struct sa1100_rtc *info = platform_get_drvdata(pdev);
+
+	if (info) {
+		spin_lock_irqsave(&info->lock, flags);
+		writel_relaxed(0, info->rtsr);
+		spin_unlock_irqrestore(&info->lock, flags);
+		clk_disable_unprepare(info->clk);
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sa1100_rtc_suspend(struct device *dev)
+{
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+	if (device_may_wakeup(dev))
+		enable_irq_wake(info->irq_alarm);
+	return 0;
+}
+
+static int sa1100_rtc_resume(struct device *dev)
+{
+	struct sa1100_rtc *info = dev_get_drvdata(dev);
+	if (device_may_wakeup(dev))
+		disable_irq_wake(info->irq_alarm);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(sa1100_rtc_pm_ops, sa1100_rtc_suspend,
+			sa1100_rtc_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id sa1100_rtc_dt_ids[] = {
+	{ .compatible = "mrvl,sa1100-rtc", },
+	{ .compatible = "mrvl,mmp-rtc", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, sa1100_rtc_dt_ids);
+#endif
+
+static struct platform_driver sa1100_rtc_driver = {
+	.probe		= sa1100_rtc_probe,
+	.remove		= sa1100_rtc_remove,
+	.driver		= {
+		.name	= "sa1100-rtc",
+		.pm	= &sa1100_rtc_pm_ops,
+		.of_match_table = of_match_ptr(sa1100_rtc_dt_ids),
+	},
+};
+
+module_platform_driver(sa1100_rtc_driver);
+
+MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
+MODULE_DESCRIPTION("SA11x0/PXA2xx Realtime Clock Driver (RTC)");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:sa1100-rtc");