From mboxrd@z Thu Jan  1 00:00:00 1970
From: andrew.ruder at elecsyscorp.com <andrew.ruder@elecsyscorp.com>
Date: Tue, 12 Aug 2014 09:25:59 -0500
Subject: [U-Boot] [PATCH 1/3] arm: pxa: use common timer functions
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From: Andrew Ruder <andrew.ruder@elecsyscorp.com>

This patch moves pxa to the common timer functions added in commit

  8dfafdd - Introduce common timer functions <Rob Herring>

The (removed) pxa timer code (specifically __udelay()) could deadlock at
the 32-bit boundary of get_ticks().  get_ticks() returned a 32-bit value
cast up to a 64-bit value.  If get_ticks() + tmo in __udelay() crossed
the 32-bit boundary, the while condition became unconditionally true and
locked the processor.  Rather than patch the specific pxa issues, simply
move everything over to the common code.

Signed-off-by: Andrew Ruder <andrew.ruder@elecsyscorp.com>
Cc: Marek Vasut <marex@denx.de>
---

32-bit rollover occurs every 22 minutes so even a long y-modem
transfer was enough to hit this issue fairly regularly.  This has been
tested.

 arch/arm/cpu/pxa/timer.c     | 69 +-------------------------------------------
 include/configs/pxa-common.h | 13 +++++++++
 2 files changed, 14 insertions(+), 68 deletions(-)

diff --git a/arch/arm/cpu/pxa/timer.c b/arch/arm/cpu/pxa/timer.c
index c4717de..11fefd5 100644
--- a/arch/arm/cpu/pxa/timer.c
+++ b/arch/arm/cpu/pxa/timer.c
@@ -6,80 +6,13 @@
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
-#include <asm/arch/pxa-regs.h>
 #include <asm/io.h>
 #include <common.h>
-#include <div64.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
-#define	TIMER_LOAD_VAL	0xffffffff
-
-#define	timestamp	(gd->arch.tbl)
-#define	lastinc		(gd->arch.lastinc)
-
-#if defined(CONFIG_CPU_PXA27X) || defined(CONFIG_CPU_MONAHANS)
-#define	TIMER_FREQ_HZ	3250000
-#elif defined(CONFIG_CPU_PXA25X)
-#define	TIMER_FREQ_HZ	3686400
-#else
-#error "Timer frequency unknown - please config PXA CPU type"
-#endif
-
-static unsigned long long tick_to_time(unsigned long long tick)
-{
-	return lldiv(tick * CONFIG_SYS_HZ, TIMER_FREQ_HZ);
-}
-
-static unsigned long long us_to_tick(unsigned long long us)
-{
-	return lldiv(us * TIMER_FREQ_HZ, 1000000);
-}
-
 int timer_init(void)
 {
-	writel(0, OSCR);
+	writel(0, CONFIG_SYS_TIMER_COUNTER);
 	return 0;
 }
-
-unsigned long long get_ticks(void)
-{
-	/* Current tick value */
-	uint32_t now = readl(OSCR);
-
-	if (now >= lastinc) {
-		/*
-		 * Normal mode (non roll)
-		 * Move stamp forward with absolute diff ticks
-		 */
-		timestamp += (now - lastinc);
-	} else {
-		/* We have rollover of incrementer */
-		timestamp += (TIMER_LOAD_VAL - lastinc) + now;
-	}
-
-	lastinc = now;
-	return timestamp;
-}
-
-ulong get_timer(ulong base)
-{
-	return tick_to_time(get_ticks()) - base;
-}
-
-void __udelay(unsigned long usec)
-{
-	unsigned long long tmp;
-	ulong tmo;
-
-	tmo = us_to_tick(usec);
-	tmp = get_ticks() + tmo;	/* get current timestamp */
-
-	while (get_ticks() < tmp)	/* loop till event */
-		 /*NOP*/;
-}
-
-ulong get_tbclk(void)
-{
-	return TIMER_FREQ_HZ;
-}
diff --git a/include/configs/pxa-common.h b/include/configs/pxa-common.h
index f0ecc34..8da37a3 100644
--- a/include/configs/pxa-common.h
+++ b/include/configs/pxa-common.h
@@ -43,4 +43,17 @@
 #define	CONFIG_USB_STORAGE
 #endif
 
+/*
+ * Generic timer support
+ */
+#if defined(CONFIG_CPU_PXA27X) || defined(CONFIG_CPU_MONAHANS)
+#define	CONFIG_SYS_TIMER_RATE	3250000
+#elif defined(CONFIG_CPU_PXA25X)
+#define	CONFIG_SYS_TIMER_RATE	3686400
+#else
+#error "Timer frequency unknown - please config PXA CPU type"
+#endif
+
+#define CONFIG_SYS_TIMER_COUNTER	0x40A00010  /* OSCR */
+
 #endif	/* __CONFIG_PXA_COMMON_H__ */
-- 
2.0.1