From: Stanley Chu <ys...@nuvoton.com>
The counter value read from TDR register may not be correct.
Read SECCNT and CNTR25M instead to get the correct timestamp.
Signed-off-by: Stanley Chu <ys...@nuvoton.com>
---
arch/arm/dts/nuvoton-common-npcm7xx.dtsi | 12 ++--
arch/arm/dts/nuvoton-common-npcm8xx.dtsi | 13 ++--
drivers/timer/npcm-timer.c | 81 ++++++------------------
3 files changed, 30 insertions(+), 76 deletions(-)
diff --git a/arch/arm/dts/nuvoton-common-npcm7xx.dtsi
b/arch/arm/dts/nuvoton-common-npcm7xx.dtsi
index feb88872fc..093d5427e3 100644
--- a/arch/arm/dts/nuvoton-common-npcm7xx.dtsi
+++ b/arch/arm/dts/nuvoton-common-npcm7xx.dtsi
@@ -95,6 +95,11 @@
compatible = "nuvoton,npcm750-rst", "syscon",
"simple-mfd";
reg = <0x801000 0x6C>;
};
+
+ timer0: timer@f0801068 {
+ compatible = "nuvoton,npcm750-timer";
+ reg = <0x801068 0x8>;
+ };
};
ahb {
@@ -245,13 +250,6 @@
status = "disabled";
};
- timer0: timer@8000 {
- compatible = "nuvoton,npcm750-timer";
- interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
- reg = <0x8000 0x1C>;
- clocks = <&clk NPCM7XX_CLK_TIMER>;
- };
-
watchdog0: watchdog@801C {
compatible = "nuvoton,npcm750-wdt";
interrupts = <GIC_SPI 47 IRQ_TYPE_LEVEL_HIGH>;
diff --git a/arch/arm/dts/nuvoton-common-npcm8xx.dtsi
b/arch/arm/dts/nuvoton-common-npcm8xx.dtsi
index db7517cc9b..be06b2a0ca 100644
--- a/arch/arm/dts/nuvoton-common-npcm8xx.dtsi
+++ b/arch/arm/dts/nuvoton-common-npcm8xx.dtsi
@@ -62,6 +62,11 @@
reg = <0x0 0xf0801000 0x0 0x1000>;
};
+ timer0: timer@f0801068 {
+ compatible = "nuvoton,npcm845-timer";
+ reg = <0x0 0xf0801068 0x0 0x8>;
+ };
+
sdhci0: sdhci@f0842000 {
compatible = "nuvoton,npcm845-sdhci";
reg = <0x0 0xf0842000 0x0 0x100>;
@@ -157,14 +162,6 @@
status = "disabled";
};
- timer0: timer@8000 {
- compatible = "nuvoton,npcm845-timer";
- interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
- reg = <0x8000 0x1C>;
- clocks = <&clk NPCM8XX_CLK_REFCLK>;
- clock-names = "refclk";
- };
-
serial0: serial@0 {
compatible = "nuvoton,npcm845-uart",
"nuvoton,npcm750-uart";
reg = <0x0 0x1000>;
diff --git a/drivers/timer/npcm-timer.c b/drivers/timer/npcm-timer.c
index 4562a6f231..af683b4c11 100644
--- a/drivers/timer/npcm-timer.c
+++ b/drivers/timer/npcm-timer.c
@@ -4,93 +4,52 @@
*/
#include <common.h>
-#include <clk.h>
#include <dm.h>
#include <timer.h>
#include <asm/io.h>
-#define NPCM_TIMER_CLOCK_RATE 1000000UL /* 1MHz timer */
-#define NPCM_TIMER_INPUT_RATE 25000000UL /* Rate of input clock
*/
-#define NPCM_TIMER_TDR_MASK GENMASK(23, 0)
-#define NPCM_TIMER_MAX_VAL NPCM_TIMER_TDR_MASK /* max counter value */
+#define NPCM_TIMER_CLOCK_RATE 25000000UL /* 25MHz */
/* Register offsets */
-#define TCR0 0x0 /* Timer Control and Status Register */
-#define TICR0 0x8 /* Timer Initial Count Register */
-#define TDR0 0x10 /* Timer Data Register */
+#define SECCNT 0x0 /* Seconds Counter Register */
+#define CNTR25M 0x4 /* 25MHz Counter Register */
-/* TCR fields */
-#define TCR_MODE_PERIODIC BIT(27)
-#define TCR_EN BIT(30)
-#define TCR_PRESCALE (NPCM_TIMER_INPUT_RATE / NPCM_TIMER_CLOCK_RATE
- 1)
-
-enum input_clock_type {
- INPUT_CLOCK_FIXED, /* input clock rate is fixed */
- INPUT_CLOCK_NON_FIXED
-};
-
-/**
- * struct npcm_timer_priv - private data for npcm timer driver
- * npcm timer is a 24-bits down-counting timer.
- *
- * @last_count: last hw counter value
- * @counter: the value to be returned for get_count ops
- */
struct npcm_timer_priv {
void __iomem *base;
- u32 last_count;
- u64 counter;
};
static u64 npcm_timer_get_count(struct udevice *dev)
{
struct npcm_timer_priv *priv = dev_get_priv(dev);
- u32 val;
+ u64 counter, reg_sec, reg_25m;
- /* The timer is counting down */
- val = readl(priv->base + TDR0) & NPCM_TIMER_TDR_MASK;
- if (val <= priv->last_count)
- priv->counter += priv->last_count - val;
- else
- priv->counter += priv->last_count + (NPCM_TIMER_MAX_VAL + 1 -
val);
- priv->last_count = val;
+ reg_sec = readl(priv->base + SECCNT);
+ reg_25m = readl(priv->base + CNTR25M);
+ /*
+ * When CNTR25M reaches 25M, it goes to 0 and SECCNT is increased by 1.
+ * When CNTR25M is zero, wait for CNTR25M to become non-zero in case
+ * SECCNT is not updated yet.
+ */
+ if (reg_25m == 0) {
+ while (reg_25m == 0)
+ reg_25m = readl(priv->base + CNTR25M);
+ reg_sec = readl(priv->base + SECCNT);
+ }
+ counter = reg_sec * NPCM_TIMER_CLOCK_RATE + reg_25m;
- return priv->counter;
+ return counter;
}
static int npcm_timer_probe(struct udevice *dev)
{
struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
struct npcm_timer_priv *priv = dev_get_priv(dev);
- enum input_clock_type type = dev_get_driver_data(dev);
- struct clk clk;
- int ret;
priv->base = dev_read_addr_ptr(dev);
if (!priv->base)
return -EINVAL;
uc_priv->clock_rate = NPCM_TIMER_CLOCK_RATE;
- if (type == INPUT_CLOCK_NON_FIXED) {
- ret = clk_get_by_index(dev, 0, &clk);
- if (ret < 0)
- return ret;
-
- ret = clk_set_rate(&clk, NPCM_TIMER_INPUT_RATE);
- if (ret < 0)
- return ret;
- }
-
- /*
- * Configure timer and start
- * periodic mode
- * timer clock rate = input clock / prescale
- */
- writel(0, priv->base + TCR0);
- writel(NPCM_TIMER_MAX_VAL, priv->base + TICR0);
- writel(TCR_EN | TCR_MODE_PERIODIC | TCR_PRESCALE,
- priv->base + TCR0);
-
return 0;
}
@@ -99,8 +58,8 @@ static const struct timer_ops npcm_timer_ops = {
};
static const struct udevice_id npcm_timer_ids[] = {
- { .compatible = "nuvoton,npcm845-timer", .data = INPUT_CLOCK_FIXED},
- { .compatible = "nuvoton,npcm750-timer", .data = INPUT_CLOCK_NON_FIXED},
+ { .compatible = "nuvoton,npcm845-timer"},
+ { .compatible = "nuvoton,npcm750-timer"},
{}
};
--
2.25.1
