1 files changed, 44 insertions, 62 deletions

diff --git a/arch/arm/mach-mmp/time.c b/arch/arm/mach-mmp/time.c
index 96ad1db0b04b..fcb190826dd1 100644
--- a/arch/arm/mach-mmp/time.c
+++ b/arch/arm/mach-mmp/time.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * linux/arch/arm/mach-mmp/time.c
  *
@@ -12,16 +13,13 @@
  * The timers module actually includes three timers, each timer with up to
  * three match comparators. Timer #0 is used here in free-running mode as
  * the clock source, and match comparator #1 used as clock event device.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
 #include <linux/clockchips.h>
+#include <linux/clk.h>
 
 #include <linux/io.h>
 #include <linux/irq.h>
@@ -31,39 +29,30 @@
 #include <linux/sched_clock.h>
 #include <asm/mach/time.h>
 
-#include "addr-map.h"
 #include "regs-timers.h"
-#include "regs-apbc.h"
-#include "irqs.h"
-#include "cputype.h"
-#include "clock.h"
-
-#ifdef CONFIG_CPU_MMP2
-#define MMP_CLOCK_FREQ		6500000
-#else
-#define MMP_CLOCK_FREQ		3250000
-#endif
-
-#define TIMERS_VIRT_BASE	TIMERS1_VIRT_BASE
+#include <linux/soc/mmp/cputype.h>
 
 #define MAX_DELTA		(0xfffffffe)
 #define MIN_DELTA		(16)
 
-static void __iomem *mmp_timer_base = TIMERS_VIRT_BASE;
+static void __iomem *mmp_timer_base;
 
 /*
- * FIXME: the timer needs some delay to stablize the counter capture
+ * Read the timer through the CVWR register. Delay is required after requesting
+ * a read. The CR register cannot be directly read due to metastability issues
+ * documented in the PXA168 software manual.
  */
 static inline uint32_t timer_read(void)
 {
-	int delay = 100;
+	uint32_t val;
+	int delay = 3;
 
 	__raw_writel(1, mmp_timer_base + TMR_CVWR(1));
 
 	while (delay--)
-		cpu_relax();
+		val = __raw_readl(mmp_timer_base + TMR_CVWR(1));
 
-	return __raw_readl(mmp_timer_base + TMR_CVWR(1));
+	return val;
 }
 
 static u64 notrace mmp_read_sched_clock(void)
@@ -163,7 +152,8 @@ static void __init timer_config(void)
 
 	__raw_writel(0x0, mmp_timer_base + TMR_CER); /* disable */
 
-	ccr &= (cpu_is_mmp2()) ? (TMR_CCR_CS_0(0) | TMR_CCR_CS_1(0)) :
+	ccr &= (cpu_is_mmp2() || cpu_is_mmp3()) ?
+		(TMR_CCR_CS_0(0) | TMR_CCR_CS_1(0)) :
 		(TMR_CCR_CS_0(3) | TMR_CCR_CS_1(3));
 	__raw_writel(ccr, mmp_timer_base + TMR_CCR);
 
@@ -182,58 +172,50 @@ static void __init timer_config(void)
 	__raw_writel(0x2, mmp_timer_base + TMR_CER);
 }
 
-static struct irqaction timer_irq = {
-	.name		= "timer",
-	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
-	.handler	= timer_interrupt,
-	.dev_id		= &ckevt,
-};
-
-void __init timer_init(int irq)
+static void __init mmp_timer_init(int irq, unsigned long rate)
 {
 	timer_config();
 
-	sched_clock_register(mmp_read_sched_clock, 32, MMP_CLOCK_FREQ);
+	sched_clock_register(mmp_read_sched_clock, 32, rate);
 
 	ckevt.cpumask = cpumask_of(0);
 
-	setup_irq(irq, &timer_irq);
+	if (request_irq(irq, timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			"timer", &ckevt))
+		pr_err("Failed to request irq %d (timer)\n", irq);
 
-	clocksource_register_hz(&cksrc, MMP_CLOCK_FREQ);
-	clockevents_config_and_register(&ckevt, MMP_CLOCK_FREQ,
-					MIN_DELTA, MAX_DELTA);
+	clocksource_register_hz(&cksrc, rate);
+	clockevents_config_and_register(&ckevt, rate, MIN_DELTA, MAX_DELTA);
 }
 
-#ifdef CONFIG_OF
-static const struct of_device_id mmp_timer_dt_ids[] = {
-	{ .compatible = "mrvl,mmp-timer", },
-	{}
-};
-
-void __init mmp_dt_init_timer(void)
+static int __init mmp_dt_init_timer(struct device_node *np)
 {
-	struct device_node *np;
+	struct clk *clk;
 	int irq, ret;
-
-	np = of_find_matching_node(NULL, mmp_timer_dt_ids);
-	if (!np) {
-		ret = -ENODEV;
-		goto out;
+	unsigned long rate;
+
+	clk = of_clk_get(np, 0);
+	if (!IS_ERR(clk)) {
+		ret = clk_prepare_enable(clk);
+		if (ret)
+			return ret;
+		rate = clk_get_rate(clk);
+	} else if (cpu_is_pj4()) {
+		rate = 6500000;
+	} else {
+		rate = 3250000;
 	}
 
 	irq = irq_of_parse_and_map(np, 0);
-	if (!irq) {
-		ret = -EINVAL;
-		goto out;
-	}
+	if (!irq)
+		return -EINVAL;
+
 	mmp_timer_base = of_iomap(np, 0);
-	if (!mmp_timer_base) {
-		ret = -ENOMEM;
-		goto out;
-	}
-	timer_init(irq);
-	return;
-out:
-	pr_err("Failed to get timer from device tree with error:%d\n", ret);
+	if (!mmp_timer_base)
+		return -ENOMEM;
+
+	mmp_timer_init(irq, rate);
+	return 0;
 }
-#endif
+
+TIMER_OF_DECLARE(mmp_timer, "mrvl,mmp-timer", mmp_dt_init_timer);