arm: mx31: use common timer functions

This patch moves mx31 to the common timer functions added in commit 8dfafdd - Introduce common timer functions <Rob Herring> The (removed) mx31 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 mx31 issues, simply move everything over to the common code. Signed-off-by: Andrew Ruder <andrew.ruder@elecsyscorp.com> Cc: Marek Vasut <marex@denx.de> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Wolfgang Denk <wd@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Helmut Raiger <helmut.raiger@hale.at>

arm: mx31: use common timer functions
This patch moves mx31 to the common timer functions added in commit 8dfafdd - Introduce common timer functions <Rob Herring> The (removed) mx31 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 mx31 issues, simply move everything over to the common code. Signed-off-by: Andrew Ruder <andrew.ruder@elecsyscorp.com> Cc: Marek Vasut <marex@denx.de> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Wolfgang Denk <wd@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Helmut Raiger <helmut.raiger@hale.at>
Andrew Ruder · Stefano Babic
1 parent 4c97f16911
Showing 2 changed files with 12 additions and 102 deletions Side-by-side Diff
arch/arm/cpu/arm1136/mx31/timer.c
arch/arm/include/asm/arch-mx31/imx-regs.h
@@ -7,9 +7,6 @@
  
 #include <common.h>
 #include <asm/arch/imx-regs.h>
-#include <asm/arch/clock.h>
-#include <div64.h>
-#include <watchdog.h>
 #include <asm/io.h>
  
 #define TIMER_BASE 0x53f90000 /* General purpose timer 1 */
@@ -28,57 +25,6 @@
  
 DECLARE_GLOBAL_DATA_PTR;
  
-/*
- * "time" is measured in 1 / CONFIG_SYS_HZ seconds,
- * "tick" is internal timer period
- */
-
-#ifdef CONFIG_MX31_TIMER_HIGH_PRECISION
-/* ~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 time_to_tick(unsigned long long time)
-{
-	time *= MXC_CLK32;
-	do_div(time, CONFIG_SYS_HZ);
-	return time;
-}
-
-static inline unsigned long long us_to_tick(unsigned long long us)
-{
-	us = us * MXC_CLK32 + 999999;
-	do_div(us, 1000000);
-	return us;
-}
-#else
-/* ~2% error */
-#define TICK_PER_TIME	((MXC_CLK32 + CONFIG_SYS_HZ / 2) / CONFIG_SYS_HZ)
-#define US_PER_TICK	(1000000 / MXC_CLK32)
-
-static inline unsigned long long tick_to_time(unsigned long long tick)
-{
-	do_div(tick, TICK_PER_TIME);
-	return tick;
-}
-
-static inline unsigned long long time_to_tick(unsigned long long time)
-{
-	return time * TICK_PER_TIME;
-}
-
-static inline unsigned long long us_to_tick(unsigned long long us)
-{
-	us += US_PER_TICK - 1;
-	do_div(us, US_PER_TICK);
-	return us;
-}
-#endif
-
 /* The 32768Hz 32-bit timer overruns in 131072 seconds */
 int timer_init(void)
 {
  
@@ -95,54 +41,8 @@
 	return 0;
 }
  
-unsigned long long get_ticks(void)
+unsigned long timer_read_counter(void)
 {
-	ulong now = GPTCNT; /* current tick value */
-
-	if (now >= gd->arch.lastinc)	/* normal mode (non roll) */
-		/* move stamp forward with absolut diff ticks */
-		gd->arch.tbl += (now - gd->arch.lastinc);
-	else			/* we have rollover of incrementer */
-		gd->arch.tbl += (0xFFFFFFFF - gd->arch.lastinc) + now;
-	gd->arch.lastinc = now;
-	return gd->arch.tbl;
-}
-
-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 timestamp 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;
+	return GPTCNT;
 }
@@ -909,10 +909,20 @@
 #define MXC_CSPIPERIOD_32KHZ	(1 << 15)
 #define MAX_SPI_BYTES	4
  
+
 #define MXC_SPI_BASE_ADDRESSES \
 	0x43fa4000, \
 	0x50010000, \
 	0x53f84000,
+
+/*
+ * Generic timer support
+ */
+#ifdef CONFIG_MX31_CLK32
+#define	CONFIG_SYS_TIMER_RATE	CONFIG_MX31_CLK32
+#else
+#define	CONFIG_SYS_TIMER_RATE	32768
+#endif
  
 #endif /* __ASM_ARCH_MX31_IMX_REGS_H */
...	...	@@ -7,9 +7,6 @@
7	7
8	8	#include <common.h>
9	9	#include <asm/arch/imx-regs.h>
10		-#include <asm/arch/clock.h>
11		-#include <div64.h>
12		-#include <watchdog.h>
13	10	#include <asm/io.h>
14	11
15	12	#define TIMER_BASE 0x53f90000 /* General purpose timer 1 */
...	...	@@ -28,57 +25,6 @@
28	25
29	26	DECLARE_GLOBAL_DATA_PTR;
30	27
31		-/*
32		- * "time" is measured in 1 / CONFIG_SYS_HZ seconds,
33		- * "tick" is internal timer period
34		- */
35		-
36		-#ifdef CONFIG_MX31_TIMER_HIGH_PRECISION
37		-/* ~0.4% error - measured with stop-watch on 100s boot-delay */
38		-static inline unsigned long long tick_to_time(unsigned long long tick)
39		-{
40		- tick *= CONFIG_SYS_HZ;
41		- do_div(tick, MXC_CLK32);
42		- return tick;
43		-}
44		-
45		-static inline unsigned long long time_to_tick(unsigned long long time)
46		-{
47		- time *= MXC_CLK32;
48		- do_div(time, CONFIG_SYS_HZ);
49		- return time;
50		-}
51		-
52		-static inline unsigned long long us_to_tick(unsigned long long us)
53		-{
54		- us = us * MXC_CLK32 + 999999;
55		- do_div(us, 1000000);
56		- return us;
57		-}
58		-#else
59		-/* ~2% error */
60		-#define TICK_PER_TIME ((MXC_CLK32 + CONFIG_SYS_HZ / 2) / CONFIG_SYS_HZ)
61		-#define US_PER_TICK (1000000 / MXC_CLK32)
62		-
63		-static inline unsigned long long tick_to_time(unsigned long long tick)
64		-{
65		- do_div(tick, TICK_PER_TIME);
66		- return tick;
67		-}
68		-
69		-static inline unsigned long long time_to_tick(unsigned long long time)
70		-{
71		- return time * TICK_PER_TIME;
72		-}
73		-
74		-static inline unsigned long long us_to_tick(unsigned long long us)
75		-{
76		- us += US_PER_TICK - 1;
77		- do_div(us, US_PER_TICK);
78		- return us;
79		-}
80		-#endif
81		-
82	28	/* The 32768Hz 32-bit timer overruns in 131072 seconds */
83	29	int timer_init(void)
84	30	{
85	31
...	...	@@ -95,54 +41,8 @@
95	41	return 0;
96	42	}
97	43
98		-unsigned long long get_ticks(void)
	44	+unsigned long timer_read_counter(void)
99	45	{
100		- ulong now = GPTCNT; /* current tick value */
101		-
102		- if (now >= gd->arch.lastinc) /* normal mode (non roll) */
103		- /* move stamp forward with absolut diff ticks */
104		- gd->arch.tbl += (now - gd->arch.lastinc);
105		- else /* we have rollover of incrementer */
106		- gd->arch.tbl += (0xFFFFFFFF - gd->arch.lastinc) + now;
107		- gd->arch.lastinc = now;
108		- return gd->arch.tbl;
109		-}
110		-
111		-ulong get_timer_masked(void)
112		-{
113		- /*
114		- * get_ticks() returns a long long (64 bit), it wraps in
115		- * 2^64 / MXC_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~
116		- * 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
117		- * 5 * 10^6 days - long enough.
118		- */
119		- return tick_to_time(get_ticks());
120		-}
121		-
122		-ulong get_timer(ulong base)
123		-{
124		- return get_timer_masked() - base;
125		-}
126		-
127		-/* delay x useconds AND preserve advance timestamp value */
128		-void __udelay(unsigned long usec)
129		-{
130		- unsigned long long tmp;
131		- ulong tmo;
132		-
133		- tmo = us_to_tick(usec);
134		- tmp = get_ticks() + tmo; /* get current timestamp */
135		-
136		- while (get_ticks() < tmp) /* loop till event */
137		- /NOP/;
138		-}
139		-
140		-/*
141		- * This function is derived from PowerPC code (timebase clock frequency).
142		- * On ARM it returns the number of timer ticks per second.
143		- */
144		-ulong get_tbclk(void)
145		-{
146		- return MXC_CLK32;
	46	+ return GPTCNT;
147	47	}
...	...	@@ -909,10 +909,20 @@
909	909	#define MXC_CSPIPERIOD_32KHZ (1 << 15)
910	910	#define MAX_SPI_BYTES 4
911	911
	912	+
912	913	#define MXC_SPI_BASE_ADDRESSES \
913	914	0x43fa4000, \
914	915	0x50010000, \
915	916	0x53f84000,
	917	+
	918	+/*
	919	+ * Generic timer support
	920	+ */
	921	+#ifdef CONFIG_MX31_CLK32
	922	+#define CONFIG_SYS_TIMER_RATE CONFIG_MX31_CLK32
	923	+#else
	924	+#define CONFIG_SYS_TIMER_RATE 32768
	925	+#endif
916	926
917	927	#endif /* __ASM_ARCH_MX31_IMX_REGS_H */