From: Andrew Ruder <andrew.ru...@elecsyscorp.com>
This patch moves mx35 to the common timer functions added in commit
8dfafdd - Introduce common timer functions <Rob Herring>
The (removed) mx35 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
locks the processor. Rather than patch the specific mx35 issues, simply
move everything over to the common code.
Signed-off-by: Andrew Ruder <andrew.ru...@elecsyscorp.com>
Cc: Marek Vasut <ma...@denx.de>
Cc: Stefano Babic <sba...@denx.de>
---
This patch has been COMPILE tested only. The situation isn't quite as
bad on mx35 as 32-bit rollover occurs in about a day and a half.
Before patch:
Configuring for woodburn board...
308 -rw-r--r-- 1 andy andy 314232 Aug 12 08:36 u-boot.bin
After patch:
Configuring for woodburn board...
308 -rw-r--r-- 1 andy andy 314208 Aug 12 08:37 u-boot.bin
arch/arm/cpu/arm1136/mx35/timer.c | 83 -------------------------------
arch/arm/include/asm/arch-mx35/imx-regs.h | 12 +++++
2 files changed, 12 insertions(+), 83 deletions(-)
diff --git a/arch/arm/cpu/arm1136/mx35/timer.c
b/arch/arm/cpu/arm1136/mx35/timer.c
index cc6166f..4edf533 100644
--- a/arch/arm/cpu/arm1136/mx35/timer.c
+++ b/arch/arm/cpu/arm1136/mx35/timer.c
@@ -9,16 +9,11 @@
#include <common.h>
#include <asm/io.h>
-#include <div64.h>
#include <asm/arch/imx-regs.h>
#include <asm/arch/crm_regs.h>
-#include <asm/arch/clock.h>
DECLARE_GLOBAL_DATA_PTR;
-#define timestamp (gd->arch.tbl)
-#define lastinc (gd->arch.lastinc)
-
/* General purpose timers bitfields */
#define GPTCR_SWR (1<<15) /* Software reset */
#define GPTCR_FRR (1<<9) /* Freerun / restart */
@@ -26,27 +21,6 @@ DECLARE_GLOBAL_DATA_PTR;
#define GPTCR_TEN (1) /* Timer enable */
/*
- * "time" is measured in 1 / CONFIG_SYS_HZ seconds,
- * "tick" is internal timer period
- */
-/* ~0.4% error - measured with stop-watch on 100s boot-delay */
-static inline unsigned long long tick_to_time(unsigned long long tick)
-{
- tick *= CONFIG_SYS_HZ;
- do_div(tick, MXC_CLK32);
-
- return tick;
-}
-
-static inline unsigned long long us_to_tick(unsigned long long us)
-{
- us = us * MXC_CLK32 + 999999;
- do_div(us, 1000000);
-
- return us;
-}
-
-/*
* nothing really to do with interrupts, just starts up a counter.
* The 32KHz 32-bit timer overruns in 134217 seconds
*/
@@ -71,60 +45,3 @@ int timer_init(void)
return 0;
}
-
-unsigned long long get_ticks(void)
-{
- struct gpt_regs *gpt = (struct gpt_regs *)GPT1_BASE_ADDR;
- ulong now = readl(&gpt->counter); /* current tick value */
-
- if (now >= lastinc) {
- /*
- * normal mode (non roll)
- * move stamp forward with absolut diff ticks
- */
- timestamp += (now - lastinc);
- } else {
- /* we have rollover of incrementer */
- timestamp += (0xFFFFFFFF - lastinc) + now;
- }
- lastinc = now;
- return timestamp;
-}
-
-ulong get_timer_masked(void)
-{
- /*
- * get_ticks() returns a long long (64 bit), it wraps in
- * 2^64 / MXC_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~
- * 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
- * 5 * 10^6 days - long enough.
- */
- return tick_to_time(get_ticks());
-}
-
-ulong get_timer(ulong base)
-{
- return get_timer_masked() - base;
-}
-
-/* delay x useconds AND preserve advance timstamp value */
-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*/;
-}
-
-/*
- * This function is derived from PowerPC code (timebase clock frequency).
- * On ARM it returns the number of timer ticks per second.
- */
-ulong get_tbclk(void)
-{
- return MXC_CLK32;
-}
diff --git a/arch/arm/include/asm/arch-mx35/imx-regs.h
b/arch/arm/include/asm/arch-mx35/imx-regs.h
index b530029..28a47ed 100644
--- a/arch/arm/include/asm/arch-mx35/imx-regs.h
+++ b/arch/arm/include/asm/arch-mx35/imx-regs.h
@@ -372,4 +372,16 @@ struct aips_regs {
#define CCM_RCSR_NF_16BIT_SEL (1 << 14)
#endif
+
+/*
+ * Generic timer support
+ */
+#ifdef CONFIG_MX35_CLK32
+#define CONFIG_SYS_TIMER_RATE CONFIG_MX35_CLK32
+#else
+#define CONFIG_SYS_TIMER_RATE 32768
+#endif
+
+#define CONFIG_SYS_TIMER_COUNTER (GPT1_BASE_ADDR+36)
+
#endif /* __ASM_ARCH_MX35_H */
--
2.0.1
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