[PATCH v2 3/3] clocksource/drivers/imx-sysctr: support i.MX95

From: Peng Fan (OSS)
Date: Thu Jan 25 2024 - 06:13:28 EST


From: Peng Fan <peng.fan@xxxxxxx>

To i.MX95 System counter module, we use Read register space to get
the counter, not the Control register space to get the counter, because
System Manager firmware not allow Linux to read Control register space,
so add a new TIMER_OF_DECLARE entry for i.MX95.

Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
---
drivers/clocksource/timer-imx-sysctr.c | 53 +++++++++++++++++++++++++++++++---
1 file changed, 49 insertions(+), 4 deletions(-)

diff --git a/drivers/clocksource/timer-imx-sysctr.c b/drivers/clocksource/timer-imx-sysctr.c
index 8d5bfb8470fb..9b7c021c3b46 100644
--- a/drivers/clocksource/timer-imx-sysctr.c
+++ b/drivers/clocksource/timer-imx-sysctr.c
@@ -8,12 +8,15 @@
#include "timer-of.h"

#define CMP_OFFSET 0x10000
+#define RD_OFFSET 0x20000

#define CNTCV_LO 0x8
#define CNTCV_HI 0xc
#define CMPCV_LO (CMP_OFFSET + 0x20)
#define CMPCV_HI (CMP_OFFSET + 0x24)
#define CMPCR (CMP_OFFSET + 0x2c)
+#define CNTCV_LO_IMX95 (RD_OFFSET + 0x8)
+#define CNTCV_HI_IMX95 (RD_OFFSET + 0xc)

#define SYS_CTR_EN 0x1
#define SYS_CTR_IRQ_MASK 0x2
@@ -22,6 +25,8 @@

struct sysctr_private {
u32 cmpcr;
+ u32 lo_off;
+ u32 hi_off;
};

static void sysctr_timer_enable(struct clock_event_device *evt, bool enable)
@@ -46,13 +51,14 @@ static void sysctr_irq_acknowledge(struct clock_event_device *evt)
static inline u64 sysctr_read_counter(struct clock_event_device *evt)
{
struct timer_of *to = to_timer_of(evt);
+ struct sysctr_private *priv = to->private_data;
void __iomem *base = timer_of_base(to);
u32 cnt_hi, tmp_hi, cnt_lo;

do {
- cnt_hi = readl_relaxed(base + CNTCV_HI);
- cnt_lo = readl_relaxed(base + CNTCV_LO);
- tmp_hi = readl_relaxed(base + CNTCV_HI);
+ cnt_hi = readl_relaxed(base + priv->hi_off);
+ cnt_lo = readl_relaxed(base + priv->lo_off);
+ tmp_hi = readl_relaxed(base + priv->hi_off);
} while (tmp_hi != cnt_hi);

return ((u64) cnt_hi << 32) | cnt_lo;
@@ -126,7 +132,7 @@ static struct timer_of to_sysctr = {
},
};

-static int __init sysctr_timer_init(struct device_node *np)
+static int __init __sysctr_timer_init(struct device_node *np)
{
struct sysctr_private *priv;
void __iomem *base;
@@ -153,9 +159,48 @@ static int __init sysctr_timer_init(struct device_node *np)
base = timer_of_base(&to_sysctr);
priv->cmpcr = readl(base + CMPCR) & ~SYS_CTR_EN;

+ return 0;
+}
+
+static int __init sysctr_timer_init(struct device_node *np)
+{
+ struct sysctr_private *priv;
+ int ret;
+
+ ret = __sysctr_timer_init(np);
+ if (ret)
+ return ret;
+
+ priv = to_sysctr.private_data;
+ priv->lo_off = CNTCV_LO;
+ priv->hi_off = CNTCV_HI;
+
clockevents_config_and_register(&to_sysctr.clkevt,
timer_of_rate(&to_sysctr),
0xff, 0x7fffffff);
+
return 0;
}
+
+static int __init sysctr_timer_imx95_init(struct device_node *np)
+{
+ struct sysctr_private *priv;
+ int ret;
+
+ ret = __sysctr_timer_init(np);
+ if (ret)
+ return ret;
+
+ priv = to_sysctr.private_data;
+ priv->lo_off = CNTCV_LO_IMX95;
+ priv->hi_off = CNTCV_HI_IMX95;
+
+ clockevents_config_and_register(&to_sysctr.clkevt,
+ timer_of_rate(&to_sysctr),
+ 0xff, 0x7fffffff);
+
+ return 0;
+}
+
TIMER_OF_DECLARE(sysctr_timer, "nxp,sysctr-timer", sysctr_timer_init);
+TIMER_OF_DECLARE(sysctr_timer_imx95, "nxp,imx95-sysctr-timer", sysctr_timer_imx95_init);

--
2.37.1