[PATCH v2 1/3] rtc: armada38x: Prepare driver to manage different versions

Gregory CLEMENT
2017-02-17T10:19:05Z

In order to prepare the introduction of the A7K/A8K version of the RTC,
this commit introduces a new data structure. This structure allows to
handle the differences between the integration of the RTC IP in the
SoCs. It will be:
- MBUS bridge timing initialization
- IRQ configuration at SoC level

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
drivers/rtc/rtc-armada38x.c | 152 +++++++++++++++++++++++++++++---------------
1 file changed, 99 insertions(+), 53 deletions(-)

diff --git a/drivers/rtc/rtc-armada38x.c b/drivers/rtc/rtc-armada38x.c
index 7cb5b27189db..b2a8e2ed71ca 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>

@@ -23,23 +24,23 @@
#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_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_BRIDGE_TIMING_CTL 0x0
-#define SOC_RTC_PERIOD_OFFS 0
-#define SOC_RTC_PERIOD_MASK (0x3FF << SOC_RTC_PERIOD_OFFS)
-#define SOC_RTC_READ_DELAY_OFFS 26
-#define SOC_RTC_READ_DELAY_MASK (0x1F << SOC_RTC_READ_DELAY_OFFS)
-
-#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_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)
+
+#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

@@ -55,6 +56,19 @@ struct armada38x_rtc {
spinlock_t lock;
int irq;
struct value_to_freq *val_to_freq;
+ struct armada38x_rtc_data *data;
+};
+
+#define ALARM1 0
+#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;
};

/*
@@ -76,19 +90,19 @@ static void rtc_delayed_write(u32 val, struct armada38x_rtc *rtc, int offset)
}

/* Update RTC-MBUS bridge timing parameters */
-static void rtc_update_mbus_timing_params(struct armada38x_rtc *rtc)
+static void rtc_update_38x_mbus_timing_params(struct armada38x_rtc *rtc)
{
u32 reg;

- reg = readl(rtc->regs_soc + SOC_RTC_BRIDGE_TIMING_CTL);
- reg &= ~SOC_RTC_PERIOD_MASK;
- reg |= 0x3FF << SOC_RTC_PERIOD_OFFS; /* Maximum value */
- reg &= ~SOC_RTC_READ_DELAY_MASK;
- reg |= 0x1F << SOC_RTC_READ_DELAY_OFFS; /* Maximum value */
- writel(reg, rtc->regs_soc + SOC_RTC_BRIDGE_TIMING_CTL);
+ 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 u32 read_rtc_register_wa(struct armada38x_rtc *rtc, u8 rtc_reg)
+static u32 read_rtc_register_38x_wa(struct armada38x_rtc *rtc, u8 rtc_reg)
{
int i, index_max = 0, max = 0;

@@ -130,13 +144,26 @@ static u32 read_rtc_register_wa(struct armada38x_rtc *rtc, u8 rtc_reg)
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 int armada38x_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct armada38x_rtc *rtc = dev_get_drvdata(dev);
unsigned long time, flags;

spin_lock_irqsave(&rtc->lock, flags);
- time = read_rtc_register_wa(rtc, RTC_TIME);
+ time = rtc->data->read_rtc_reg(rtc, RTC_TIME);
spin_unlock_irqrestore(&rtc->lock, flags);

rtc_time_to_tm(time, tm);
@@ -167,12 +194,14 @@ 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 = read_rtc_register_wa(rtc, RTC_ALARM1);
- val = read_rtc_register_wa(rtc, 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);

@@ -185,9 +214,10 @@ 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);

@@ -196,13 +226,11 @@ 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);
@@ -215,14 +243,15 @@ 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);

@@ -234,24 +263,23 @@ 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 = read_rtc_register_wa(rtc, 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;
@@ -276,13 +304,37 @@ static const struct rtc_class_ops armada38x_rtc_ops_noirq = {
.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,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id armada38x_rtc_of_match_table[] = {
+ {
+ .compatible = "marvell,armada-380-rtc",
+ .data = &armada38x_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)
@@ -327,9 +379,11 @@ static __init int armada38x_rtc_probe(struct platform_device *pdev)
*/
ops = &armada38x_rtc_ops_noirq;
}
+ rtc->data = (struct armada38x_rtc_data *)match->data;
+

/* Update RTC-MBUS bridge timing parameters */
- rtc_update_mbus_timing_params(rtc);
+ rtc->data->update_mbus_timing(rtc);

rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name,
ops, THIS_MODULE);
@@ -359,7 +413,7 @@ static int armada38x_rtc_resume(struct device *dev)
struct armada38x_rtc *rtc = dev_get_drvdata(dev);

/* Update RTC-MBUS bridge timing parameters */
- rtc_update_mbus_timing_params(rtc);
+ rtc->data->update_mbus_timing(rtc);

return disable_irq_wake(rtc->irq);
}
@@ -371,14 +425,6 @@ 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",
--
2.11.0