1 files changed, 255 insertions, 63 deletions

diff --git a/drivers/rtc/rtc-armada38x.c b/drivers/rtc/rtc-armada38x.c
index 9a3f2a6f512e..21f355c37eab 100644
--- a/drivers/rtc/rtc-armada38x.c
+++ b/drivers/rtc/rtc-armada38x.c
@@ -16,6 +16,7 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/rtc.h>
 
@@ -23,17 +24,48 @@
 #define RTC_STATUS_ALARM1	    BIT(0)
 #define RTC_STATUS_ALARM2	    BIT(1)
 #define RTC_IRQ1_CONF	    0x4
-#define RTC_IRQ1_AL_EN		    BIT(0)
-#define RTC_IRQ1_FREQ_EN	    BIT(1)
-#define RTC_IRQ1_FREQ_1HZ	    BIT(2)
+#define RTC_IRQ2_CONF	    0x8
+#define RTC_IRQ_AL_EN		    BIT(0)
+#define RTC_IRQ_FREQ_EN		    BIT(1)
+#define RTC_IRQ_FREQ_1HZ	    BIT(2)
+
 #define RTC_TIME	    0xC
 #define RTC_ALARM1	    0x10
-
-#define SOC_RTC_INTERRUPT   0x8
-#define SOC_RTC_ALARM1		BIT(0)
-#define SOC_RTC_ALARM2		BIT(1)
-#define SOC_RTC_ALARM1_MASK	BIT(2)
-#define SOC_RTC_ALARM2_MASK	BIT(3)
+#define RTC_ALARM2	    0x14
+
+/* Armada38x SoC registers  */
+#define RTC_38X_BRIDGE_TIMING_CTL   0x0
+#define RTC_38X_PERIOD_OFFS		0
+#define RTC_38X_PERIOD_MASK		(0x3FF << RTC_38X_PERIOD_OFFS)
+#define RTC_38X_READ_DELAY_OFFS		26
+#define RTC_38X_READ_DELAY_MASK		(0x1F << RTC_38X_READ_DELAY_OFFS)
+
+/* Armada 7K/8K registers  */
+#define RTC_8K_BRIDGE_TIMING_CTL0    0x0
+#define RTC_8K_WRCLK_PERIOD_OFFS	0
+#define RTC_8K_WRCLK_PERIOD_MASK	(0xFFFF << RTC_8K_WRCLK_PERIOD_OFFS)
+#define RTC_8K_WRCLK_SETUP_OFFS		16
+#define RTC_8K_WRCLK_SETUP_MASK		(0xFFFF << RTC_8K_WRCLK_SETUP_OFFS)
+#define RTC_8K_BRIDGE_TIMING_CTL1   0x4
+#define RTC_8K_READ_DELAY_OFFS		0
+#define RTC_8K_READ_DELAY_MASK		(0xFFFF << RTC_8K_READ_DELAY_OFFS)
+
+#define RTC_8K_ISR		    0x10
+#define RTC_8K_IMR		    0x14
+#define RTC_8K_ALARM2			BIT(0)
+
+#define SOC_RTC_INTERRUPT	    0x8
+#define SOC_RTC_ALARM1			BIT(0)
+#define SOC_RTC_ALARM2			BIT(1)
+#define SOC_RTC_ALARM1_MASK		BIT(2)
+#define SOC_RTC_ALARM2_MASK		BIT(3)
+
+#define SAMPLE_NR 100
+
+struct value_to_freq {
+	u32 value;
+	u8 freq;
+};
 
 struct armada38x_rtc {
 	struct rtc_device   *rtc_dev;
@@ -41,38 +73,153 @@ struct armada38x_rtc {
 	void __iomem	    *regs_soc;
 	spinlock_t	    lock;
 	int		    irq;
+	struct value_to_freq *val_to_freq;
+	struct armada38x_rtc_data *data;
+};
+
+#define ALARM1	0
+#define ALARM2	1
+
+#define ALARM_REG(base, alarm)	 ((base) + (alarm) * sizeof(u32))
+
+struct armada38x_rtc_data {
+	/* Initialize the RTC-MBUS bridge timing */
+	void (*update_mbus_timing)(struct armada38x_rtc *rtc);
+	u32 (*read_rtc_reg)(struct armada38x_rtc *rtc, u8 rtc_reg);
+	void (*clear_isr)(struct armada38x_rtc *rtc);
+	void (*unmask_interrupt)(struct armada38x_rtc *rtc);
+	u32 alarm;
 };
 
 /*
  * According to the datasheet, the OS should wait 5us after every
  * register write to the RTC hard macro so that the required update
  * can occur without holding off the system bus
+ * According to errata RES-3124064, Write to any RTC register
+ * may fail. As a workaround, before writing to RTC
+ * register, issue a dummy write of 0x0 twice to RTC Status
+ * register.
  */
+
 static void rtc_delayed_write(u32 val, struct armada38x_rtc *rtc, int offset)
 {
+	writel(0, rtc->regs + RTC_STATUS);
+	writel(0, rtc->regs + RTC_STATUS);
 	writel(val, rtc->regs + offset);
 	udelay(5);
 }
 
+/* Update RTC-MBUS bridge timing parameters */
+static void rtc_update_38x_mbus_timing_params(struct armada38x_rtc *rtc)
+{
+	u32 reg;
+
+	reg = readl(rtc->regs_soc + RTC_38X_BRIDGE_TIMING_CTL);
+	reg &= ~RTC_38X_PERIOD_MASK;
+	reg |= 0x3FF << RTC_38X_PERIOD_OFFS; /* Maximum value */
+	reg &= ~RTC_38X_READ_DELAY_MASK;
+	reg |= 0x1F << RTC_38X_READ_DELAY_OFFS; /* Maximum value */
+	writel(reg, rtc->regs_soc + RTC_38X_BRIDGE_TIMING_CTL);
+}
+
+static void rtc_update_8k_mbus_timing_params(struct armada38x_rtc *rtc)
+{
+	u32 reg;
+
+	reg = readl(rtc->regs_soc + RTC_8K_BRIDGE_TIMING_CTL0);
+	reg &= ~RTC_8K_WRCLK_PERIOD_MASK;
+	reg |= 0x3FF << RTC_8K_WRCLK_PERIOD_OFFS;
+	reg &= ~RTC_8K_WRCLK_SETUP_MASK;
+	reg |= 0x29 << RTC_8K_WRCLK_SETUP_OFFS;
+	writel(reg, rtc->regs_soc + RTC_8K_BRIDGE_TIMING_CTL0);
+
+	reg = readl(rtc->regs_soc + RTC_8K_BRIDGE_TIMING_CTL1);
+	reg &= ~RTC_8K_READ_DELAY_MASK;
+	reg |= 0x3F << RTC_8K_READ_DELAY_OFFS;
+	writel(reg, rtc->regs_soc + RTC_8K_BRIDGE_TIMING_CTL1);
+}
+
+static u32 read_rtc_register(struct armada38x_rtc *rtc, u8 rtc_reg)
+{
+	return readl(rtc->regs + rtc_reg);
+}
+
+static u32 read_rtc_register_38x_wa(struct armada38x_rtc *rtc, u8 rtc_reg)
+{
+	int i, index_max = 0, max = 0;
+
+	for (i = 0; i < SAMPLE_NR; i++) {
+		rtc->val_to_freq[i].value = readl(rtc->regs + rtc_reg);
+		rtc->val_to_freq[i].freq = 0;
+	}
+
+	for (i = 0; i < SAMPLE_NR; i++) {
+		int j = 0;
+		u32 value = rtc->val_to_freq[i].value;
+
+		while (rtc->val_to_freq[j].freq) {
+			if (rtc->val_to_freq[j].value == value) {
+				rtc->val_to_freq[j].freq++;
+				break;
+			}
+			j++;
+		}
+
+		if (!rtc->val_to_freq[j].freq) {
+			rtc->val_to_freq[j].value = value;
+			rtc->val_to_freq[j].freq = 1;
+		}
+
+		if (rtc->val_to_freq[j].freq > max) {
+			index_max = j;
+			max = rtc->val_to_freq[j].freq;
+		}
+
+		/*
+		 * If a value already has half of the sample this is the most
+		 * frequent one and we can stop the research right now
+		 */
+		if (max > SAMPLE_NR / 2)
+			break;
+	}
+
+	return rtc->val_to_freq[index_max].value;
+}
+
+static void armada38x_clear_isr(struct armada38x_rtc *rtc)
+{
+	u32 val = readl(rtc->regs_soc + SOC_RTC_INTERRUPT);
+
+	writel(val & ~SOC_RTC_ALARM1, rtc->regs_soc + SOC_RTC_INTERRUPT);
+}
+
+static void armada38x_unmask_interrupt(struct armada38x_rtc *rtc)
+{
+	u32 val = readl(rtc->regs_soc + SOC_RTC_INTERRUPT);
+
+	writel(val | SOC_RTC_ALARM1_MASK, rtc->regs_soc + SOC_RTC_INTERRUPT);
+}
+
+static void armada8k_clear_isr(struct armada38x_rtc *rtc)
+{
+	writel(RTC_8K_ALARM2, rtc->regs_soc + RTC_8K_ISR);
+}
+
+static void armada8k_unmask_interrupt(struct armada38x_rtc *rtc)
+{
+	writel(RTC_8K_ALARM2, rtc->regs_soc + RTC_8K_IMR);
+}
+
 static int armada38x_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
 	struct armada38x_rtc *rtc = dev_get_drvdata(dev);
-	unsigned long time, time_check, flags;
+	unsigned long time, flags;
 
 	spin_lock_irqsave(&rtc->lock, flags);
-	time = readl(rtc->regs + RTC_TIME);
-	/*
-	 * WA for failing time set attempts. As stated in HW ERRATA if
-	 * more than one second between two time reads is detected
-	 * then read once again.
-	 */
-	time_check = readl(rtc->regs + RTC_TIME);
-	if ((time_check - time) > 1)
-		time_check = readl(rtc->regs + RTC_TIME);
-
+	time = rtc->data->read_rtc_reg(rtc, RTC_TIME);
 	spin_unlock_irqrestore(&rtc->lock, flags);
 
-	rtc_time_to_tm(time_check, tm);
+	rtc_time_to_tm(time, tm);
 
 	return 0;
 }
@@ -87,16 +234,9 @@ static int armada38x_rtc_set_time(struct device *dev, struct rtc_time *tm)
 
 	if (ret)
 		goto out;
-	/*
-	 * According to errata FE-3124064, Write to RTC TIME register
-	 * may fail. As a workaround, after writing to RTC TIME
-	 * register, issue a dummy write of 0x0 twice to RTC Status
-	 * register.
-	 */
+
 	spin_lock_irqsave(&rtc->lock, flags);
 	rtc_delayed_write(time, rtc, RTC_TIME);
-	rtc_delayed_write(0, rtc, RTC_STATUS);
-	rtc_delayed_write(0, rtc, RTC_STATUS);
 	spin_unlock_irqrestore(&rtc->lock, flags);
 
 out:
@@ -107,12 +247,14 @@ static int armada38x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct armada38x_rtc *rtc = dev_get_drvdata(dev);
 	unsigned long time, flags;
+	u32 reg = ALARM_REG(RTC_ALARM1, rtc->data->alarm);
+	u32 reg_irq = ALARM_REG(RTC_IRQ1_CONF, rtc->data->alarm);
 	u32 val;
 
 	spin_lock_irqsave(&rtc->lock, flags);
 
-	time = readl(rtc->regs + RTC_ALARM1);
-	val = readl(rtc->regs + RTC_IRQ1_CONF) & RTC_IRQ1_AL_EN;
+	time = rtc->data->read_rtc_reg(rtc, reg);
+	val = rtc->data->read_rtc_reg(rtc, reg_irq) & RTC_IRQ_AL_EN;
 
 	spin_unlock_irqrestore(&rtc->lock, flags);
 
@@ -125,9 +267,10 @@ static int armada38x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 static int armada38x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct armada38x_rtc *rtc = dev_get_drvdata(dev);
+	u32 reg = ALARM_REG(RTC_ALARM1, rtc->data->alarm);
+	u32 reg_irq = ALARM_REG(RTC_IRQ1_CONF, rtc->data->alarm);
 	unsigned long time, flags;
 	int ret = 0;
-	u32 val;
 
 	ret = rtc_tm_to_time(&alrm->time, &time);
 
@@ -136,13 +279,11 @@ static int armada38x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 
 	spin_lock_irqsave(&rtc->lock, flags);
 
-	rtc_delayed_write(time, rtc, RTC_ALARM1);
+	rtc_delayed_write(time, rtc, reg);
 
 	if (alrm->enabled) {
-			rtc_delayed_write(RTC_IRQ1_AL_EN, rtc, RTC_IRQ1_CONF);
-			val = readl(rtc->regs_soc + SOC_RTC_INTERRUPT);
-			writel(val | SOC_RTC_ALARM1_MASK,
-			       rtc->regs_soc + SOC_RTC_INTERRUPT);
+		rtc_delayed_write(RTC_IRQ_AL_EN, rtc, reg_irq);
+		rtc->data->unmask_interrupt(rtc);
 	}
 
 	spin_unlock_irqrestore(&rtc->lock, flags);
@@ -155,14 +296,15 @@ static int armada38x_rtc_alarm_irq_enable(struct device *dev,
 					 unsigned int enabled)
 {
 	struct armada38x_rtc *rtc = dev_get_drvdata(dev);
+	u32 reg_irq = ALARM_REG(RTC_IRQ1_CONF, rtc->data->alarm);
 	unsigned long flags;
 
 	spin_lock_irqsave(&rtc->lock, flags);
 
 	if (enabled)
-		rtc_delayed_write(RTC_IRQ1_AL_EN, rtc, RTC_IRQ1_CONF);
+		rtc_delayed_write(RTC_IRQ_AL_EN, rtc, reg_irq);
 	else
-		rtc_delayed_write(0, rtc, RTC_IRQ1_CONF);
+		rtc_delayed_write(0, rtc, reg_irq);
 
 	spin_unlock_irqrestore(&rtc->lock, flags);
 
@@ -174,24 +316,23 @@ static irqreturn_t armada38x_rtc_alarm_irq(int irq, void *data)
 	struct armada38x_rtc *rtc = data;
 	u32 val;
 	int event = RTC_IRQF | RTC_AF;
+	u32 reg_irq = ALARM_REG(RTC_IRQ1_CONF, rtc->data->alarm);
 
 	dev_dbg(&rtc->rtc_dev->dev, "%s:irq(%d)\n", __func__, irq);
 
 	spin_lock(&rtc->lock);
 
-	val = readl(rtc->regs_soc + SOC_RTC_INTERRUPT);
-
-	writel(val & ~SOC_RTC_ALARM1, rtc->regs_soc + SOC_RTC_INTERRUPT);
-	val = readl(rtc->regs + RTC_IRQ1_CONF);
-	/* disable all the interrupts for alarm 1 */
-	rtc_delayed_write(0, rtc, RTC_IRQ1_CONF);
+	rtc->data->clear_isr(rtc);
+	val = rtc->data->read_rtc_reg(rtc, reg_irq);
+	/* disable all the interrupts for alarm*/
+	rtc_delayed_write(0, rtc, reg_irq);
 	/* Ack the event */
-	rtc_delayed_write(RTC_STATUS_ALARM1, rtc, RTC_STATUS);
+	rtc_delayed_write(1 << rtc->data->alarm, rtc, RTC_STATUS);
 
 	spin_unlock(&rtc->lock);
 
-	if (val & RTC_IRQ1_FREQ_EN) {
-		if (val & RTC_IRQ1_FREQ_1HZ)
+	if (val & RTC_IRQ_FREQ_EN) {
+		if (val & RTC_IRQ_FREQ_1HZ)
 			event |= RTC_UF;
 		else
 			event |= RTC_PF;
@@ -202,7 +343,7 @@ static irqreturn_t armada38x_rtc_alarm_irq(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
-static struct rtc_class_ops armada38x_rtc_ops = {
+static const struct rtc_class_ops armada38x_rtc_ops = {
 	.read_time = armada38x_rtc_read_time,
 	.set_time = armada38x_rtc_set_time,
 	.read_alarm = armada38x_rtc_read_alarm,
@@ -210,17 +351,65 @@ static struct rtc_class_ops armada38x_rtc_ops = {
 	.alarm_irq_enable = armada38x_rtc_alarm_irq_enable,
 };
 
+static const struct rtc_class_ops armada38x_rtc_ops_noirq = {
+	.read_time = armada38x_rtc_read_time,
+	.set_time = armada38x_rtc_set_time,
+	.read_alarm = armada38x_rtc_read_alarm,
+};
+
+static const struct armada38x_rtc_data armada38x_data = {
+	.update_mbus_timing = rtc_update_38x_mbus_timing_params,
+	.read_rtc_reg = read_rtc_register_38x_wa,
+	.clear_isr = armada38x_clear_isr,
+	.unmask_interrupt = armada38x_unmask_interrupt,
+	.alarm = ALARM1,
+};
+
+static const struct armada38x_rtc_data armada8k_data = {
+	.update_mbus_timing = rtc_update_8k_mbus_timing_params,
+	.read_rtc_reg = read_rtc_register,
+	.clear_isr = armada8k_clear_isr,
+	.unmask_interrupt = armada8k_unmask_interrupt,
+	.alarm = ALARM2,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id armada38x_rtc_of_match_table[] = {
+	{
+		.compatible = "marvell,armada-380-rtc",
+		.data = &armada38x_data,
+	},
+	{
+		.compatible = "marvell,armada-8k-rtc",
+		.data = &armada8k_data,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, armada38x_rtc_of_match_table);
+#endif
+
 static __init int armada38x_rtc_probe(struct platform_device *pdev)
 {
+	const struct rtc_class_ops *ops;
 	struct resource *res;
 	struct armada38x_rtc *rtc;
+	const struct of_device_id *match;
 	int ret;
 
+	match = of_match_device(armada38x_rtc_of_match_table, &pdev->dev);
+	if (!match)
+		return -ENODEV;
+
 	rtc = devm_kzalloc(&pdev->dev, sizeof(struct armada38x_rtc),
 			    GFP_KERNEL);
 	if (!rtc)
 		return -ENOMEM;
 
+	rtc->val_to_freq = devm_kcalloc(&pdev->dev, SAMPLE_NR,
+				sizeof(struct value_to_freq), GFP_KERNEL);
+	if (!rtc->val_to_freq)
+		return -ENOMEM;
+
 	spin_lock_init(&rtc->lock);
 
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rtc");
@@ -242,19 +431,27 @@ static __init int armada38x_rtc_probe(struct platform_device *pdev)
 				0, pdev->name, rtc) < 0) {
 		dev_warn(&pdev->dev, "Interrupt not available.\n");
 		rtc->irq = -1;
+	}
+	platform_set_drvdata(pdev, rtc);
+
+	if (rtc->irq != -1) {
+		device_init_wakeup(&pdev->dev, 1);
+		ops = &armada38x_rtc_ops;
+	} else {
 		/*
 		 * If there is no interrupt available then we can't
 		 * use the alarm
 		 */
-		armada38x_rtc_ops.set_alarm = NULL;
-		armada38x_rtc_ops.alarm_irq_enable = NULL;
+		ops = &armada38x_rtc_ops_noirq;
 	}
-	platform_set_drvdata(pdev, rtc);
-	if (rtc->irq != -1)
-		device_init_wakeup(&pdev->dev, 1);
+	rtc->data = (struct armada38x_rtc_data *)match->data;
+
+
+	/* Update RTC-MBUS bridge timing parameters */
+	rtc->data->update_mbus_timing(rtc);
 
 	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name,
-					&armada38x_rtc_ops, THIS_MODULE);
+						ops, THIS_MODULE);
 	if (IS_ERR(rtc->rtc_dev)) {
 		ret = PTR_ERR(rtc->rtc_dev);
 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
@@ -280,6 +477,9 @@ static int armada38x_rtc_resume(struct device *dev)
 	if (device_may_wakeup(dev)) {
 		struct armada38x_rtc *rtc = dev_get_drvdata(dev);
 
+		/* Update RTC-MBUS bridge timing parameters */
+		rtc->data->update_mbus_timing(rtc);
+
 		return disable_irq_wake(rtc->irq);
 	}
 
@@ -290,14 +490,6 @@ static int armada38x_rtc_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(armada38x_rtc_pm_ops,
 			 armada38x_rtc_suspend, armada38x_rtc_resume);
 
-#ifdef CONFIG_OF
-static const struct of_device_id armada38x_rtc_of_match_table[] = {
-	{ .compatible = "marvell,armada-380-rtc", },
-	{}
-};
-MODULE_DEVICE_TABLE(of, armada38x_rtc_of_match_table);
-#endif
-
 static struct platform_driver armada38x_rtc_driver = {
 	.driver		= {
 		.name	= "armada38x-rtc",