aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAtsushi Nemoto <anemo@mba.ocn.ne.jp>2006-10-24 00:21:27 +0900
committerRalf Baechle <ralf@linux-mips.org>2006-10-31 20:13:23 +0000
commit16b7b2ac0148e839da86af8747b6fa4aad43a9b7 (patch)
tree93912ae2e9c64f71a8cca028677fd918b9edf0fa
parent70e46f48cb5933119712ee27945309a4bfc98282 (diff)
[MIPS] Fixup migration to GENERIC_TIME
Since we already moved to GENERIC_TIME, we should implement alternatives of old do_gettimeoffset routines to get sub-jiffies resolution from gettimeofday(). This patch includes: * MIPS clocksource support (based on works by Manish Lachwani). * remove unused gettimeoffset routines and related codes. * remove unised 64bit do_div64_32(). * simplify mips_hpt_init. (no argument needed, __init tag) * simplify c0_hpt_timer_init. (no need to write to c0_count) * remove some hpt_init routines. * mips_hpt_mask variable to specify bitmask of hpt value. * convert jmr3927_do_gettimeoffset to jmr3927_hpt_read. * convert ip27_do_gettimeoffset to ip27_hpt_read. * convert bcm1480_do_gettimeoffset to bcm1480_hpt_read. * simplify sb1250 hpt functions. (no need to subtract and shift) Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
-rw-r--r--Documentation/mips/time.README39
-rw-r--r--arch/mips/au1000/common/time.c98
-rw-r--r--arch/mips/dec/time.c9
-rw-r--r--arch/mips/jmr3927/rbhma3100/setup.c40
-rw-r--r--arch/mips/kernel/time.c319
-rw-r--r--arch/mips/philips/pnx8550/common/time.c4
-rw-r--r--arch/mips/pmc-sierra/yosemite/smp.c6
-rw-r--r--arch/mips/sgi-ip27/ip27-timer.c16
-rw-r--r--arch/mips/sibyte/bcm1480/time.c33
-rw-r--r--arch/mips/sibyte/sb1250/time.c28
-rw-r--r--include/asm-mips/div64.h21
-rw-r--r--include/asm-mips/sibyte/sb1250.h2
-rw-r--r--include/asm-mips/time.h10
13 files changed, 103 insertions, 522 deletions
diff --git a/Documentation/mips/time.README b/Documentation/mips/time.README
index e1304b6bc48..a4ce603ed3b 100644
--- a/Documentation/mips/time.README
+++ b/Documentation/mips/time.README
@@ -38,19 +38,14 @@ The new time code provide the following services:
a) Implements functions required by Linux common code:
time_init
- do_gettimeofday
- do_settimeofday
b) provides an abstraction of RTC and null RTC implementation as default.
extern unsigned long (*rtc_get_time)(void);
extern int (*rtc_set_time)(unsigned long);
- c) a set of gettimeoffset functions for different CPUs and different
- needs.
-
- d) high-level and low-level timer interrupt routines where the timer
- interrupt source may or may not be the CPU timer. The high-level
- routine is dispatched through do_IRQ() while the low-level is
+ c) high-level and low-level timer interrupt routines where the timer
+ interrupt source may or may not be the CPU timer. The high-level
+ routine is dispatched through do_IRQ() while the low-level is
dispatched in assemably code (usually int-handler.S)
@@ -73,8 +68,7 @@ the following functions or values:
c) (optional) board-specific RTC routines.
d) (optional) mips_hpt_frequency - It must be definied if the board
- is using CPU counter for timer interrupt or it is using fixed rate
- gettimeoffset().
+ is using CPU counter for timer interrupt.
PORTING GUIDE
@@ -89,16 +83,6 @@ Step 1: decide how you like to implement the time services.
If the answer is no, you need a timer to provide the timer interrupt
at 100 HZ speed.
- You cannot use the fast gettimeoffset functions, i.e.,
-
- unsigned long fixed_rate_gettimeoffset(void);
- unsigned long calibrate_div32_gettimeoffset(void);
- unsigned long calibrate_div64_gettimeoffset(void);
-
- You can use null_gettimeoffset() will gives the same time resolution as
- jiffy. Or you can implement your own gettimeoffset (probably based on
- some ad hoc hardware on your machine.)
-
c) The following sub steps assume your CPU has counter register.
Do you plan to use the CPU counter register as the timer interrupt
or use an exnternal timer?
@@ -123,8 +107,8 @@ Step 3: implement rtc routines, board_time_init() and plat_timer_setup()
board_time_init() -
a) (optional) set up RTC routines,
b) (optional) calibrate and set the mips_hpt_frequency
- (only needed if you intended to use fixed_rate_gettimeoffset
- or use cpu counter as timer interrupt source)
+ (only needed if you intended to use cpu counter as timer interrupt
+ source)
plat_timer_setup() -
a) (optional) over-write any choices made above by time_init().
@@ -154,8 +138,8 @@ for some of the functions in time.c.
For example, you may define your own timer interrupt routine, which does
some of its own processing and then calls timer_interrupt().
-You can also over-ride any of the built-in functions (gettimeoffset,
-RTC routines and/or timer interrupt routine).
+You can also over-ride any of the built-in functions (RTC routines
+and/or timer interrupt routine).
PORTING NOTES FOR SMP
@@ -187,10 +171,3 @@ You need to decide on your timer interrupt sources.
You can also do the low-level version of those interrupt routines,
following similar dispatching routes described above.
-
-Note about do_gettimeoffset():
-
- It is very likely the CPU counter registers are not sync'ed up in a SMP box.
- Therefore you cannot really use the many of the existing routines that
- are based on CPU counter. You should wirte your own gettimeoffset rouinte
- if you want intra-jiffy resolution.
diff --git a/arch/mips/au1000/common/time.c b/arch/mips/au1000/common/time.c
index 6768638883e..fa1c62f0551 100644
--- a/arch/mips/au1000/common/time.c
+++ b/arch/mips/au1000/common/time.c
@@ -53,9 +53,6 @@ static unsigned long r4k_cur; /* What counter should be at next timer irq */
int no_au1xxx_32khz;
extern int allow_au1k_wait; /* default off for CP0 Counter */
-/* Cycle counter value at the previous timer interrupt.. */
-static unsigned int timerhi = 0, timerlo = 0;
-
#ifdef CONFIG_PM
#if HZ < 100 || HZ > 1000
#error "unsupported HZ value! Must be in [100,1000]"
@@ -90,10 +87,6 @@ void mips_timer_interrupt(void)
goto null;
do {
- count = read_c0_count();
- timerhi += (count < timerlo); /* Wrap around */
- timerlo = count;
-
kstat_this_cpu.irqs[irq]++;
do_timer(1);
#ifndef CONFIG_SMP
@@ -297,88 +290,6 @@ unsigned long cal_r4koff(void)
return (cpu_speed / HZ);
}
-/* This is for machines which generate the exact clock. */
-#define USECS_PER_JIFFY (1000000/HZ)
-#define USECS_PER_JIFFY_FRAC (0x100000000LL*1000000/HZ&0xffffffff)
-
-static unsigned long
-div64_32(unsigned long v1, unsigned long v2, unsigned long v3)
-{
- unsigned long r0;
- do_div64_32(r0, v1, v2, v3);
- return r0;
-}
-
-static unsigned long do_fast_cp0_gettimeoffset(void)
-{
- u32 count;
- unsigned long res, tmp;
- unsigned long r0;
-
- /* Last jiffy when do_fast_gettimeoffset() was called. */
- static unsigned long last_jiffies=0;
- unsigned long quotient;
-
- /*
- * Cached "1/(clocks per usec)*2^32" value.
- * It has to be recalculated once each jiffy.
- */
- static unsigned long cached_quotient=0;
-
- tmp = jiffies;
-
- quotient = cached_quotient;
-
- if (tmp && last_jiffies != tmp) {
- last_jiffies = tmp;
- if (last_jiffies != 0) {
- r0 = div64_32(timerhi, timerlo, tmp);
- quotient = div64_32(USECS_PER_JIFFY, USECS_PER_JIFFY_FRAC, r0);
- cached_quotient = quotient;
- }
- }
-
- /* Get last timer tick in absolute kernel time */
- count = read_c0_count();
-
- /* .. relative to previous jiffy (32 bits is enough) */
- count -= timerlo;
-
- __asm__("multu\t%1,%2\n\t"
- "mfhi\t%0"
- : "=r" (res)
- : "r" (count), "r" (quotient)
- : "hi", "lo", GCC_REG_ACCUM);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY-1;
-
- return res;
-}
-
-#ifdef CONFIG_PM
-static unsigned long do_fast_pm_gettimeoffset(void)
-{
- unsigned long pc0;
- unsigned long offset;
-
- pc0 = au_readl(SYS_TOYREAD);
- au_sync();
- offset = pc0 - last_pc0;
- if (offset > 2*MATCH20_INC) {
- printk("huge offset %x, last_pc0 %x last_match20 %x pc0 %x\n",
- (unsigned)offset, (unsigned)last_pc0,
- (unsigned)last_match20, (unsigned)pc0);
- }
- offset = (unsigned long)((offset * 305) / 10);
- return offset;
-}
-#endif
-
void __init plat_timer_setup(struct irqaction *irq)
{
unsigned int est_freq;
@@ -416,7 +327,6 @@ void __init plat_timer_setup(struct irqaction *irq)
unsigned int c0_status;
printk("WARNING: no 32KHz clock found.\n");
- do_gettimeoffset = do_fast_cp0_gettimeoffset;
/* Ensure we get CPO_COUNTER interrupts.
*/
@@ -441,19 +351,11 @@ void __init plat_timer_setup(struct irqaction *irq)
while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20);
startup_match20_interrupt(counter0_irq);
- do_gettimeoffset = do_fast_pm_gettimeoffset;
-
/* We can use the real 'wait' instruction.
*/
allow_au1k_wait = 1;
}
-#else
- /* We have to do this here instead of in timer_init because
- * the generic code in arch/mips/kernel/time.c will write
- * over our function pointer.
- */
- do_gettimeoffset = do_fast_cp0_gettimeoffset;
#endif
}
diff --git a/arch/mips/dec/time.c b/arch/mips/dec/time.c
index 4cf0c06e241..69e424e9ab6 100644
--- a/arch/mips/dec/time.c
+++ b/arch/mips/dec/time.c
@@ -160,11 +160,6 @@ static unsigned int dec_ioasic_hpt_read(void)
return ioasic_read(IO_REG_FCTR);
}
-static void dec_ioasic_hpt_init(unsigned int count)
-{
- ioasic_write(IO_REG_FCTR, ioasic_read(IO_REG_FCTR) - count);
-}
-
void __init dec_time_init(void)
{
@@ -174,11 +169,9 @@ void __init dec_time_init(void)
mips_timer_state = dec_timer_state;
mips_timer_ack = dec_timer_ack;
- if (!cpu_has_counter && IOASIC) {
+ if (!cpu_has_counter && IOASIC)
/* For pre-R4k systems we use the I/O ASIC's counter. */
mips_hpt_read = dec_ioasic_hpt_read;
- mips_hpt_init = dec_ioasic_hpt_init;
- }
/* Set up the rate of periodic DS1287 interrupts. */
CMOS_WRITE(RTC_REF_CLCK_32KHZ | (16 - __ffs(HZ)), RTC_REG_A);
diff --git a/arch/mips/jmr3927/rbhma3100/setup.c b/arch/mips/jmr3927/rbhma3100/setup.c
index 025434054ed..16e5dfe7aa8 100644
--- a/arch/mips/jmr3927/rbhma3100/setup.c
+++ b/arch/mips/jmr3927/rbhma3100/setup.c
@@ -170,12 +170,20 @@ static void jmr3927_machine_power_off(void)
while (1);
}
+static unsigned int jmr3927_hpt_read(void)
+{
+ /* We assume this function is called xtime_lock held. */
+ return jiffies * (JMR3927_TIMER_CLK / HZ) + jmr3927_tmrptr->trr;
+}
+
#define USE_RTC_DS1742
#ifdef USE_RTC_DS1742
extern void rtc_ds1742_init(unsigned long base);
#endif
static void __init jmr3927_time_init(void)
{
+ mips_hpt_read = jmr3927_hpt_read;
+ mips_hpt_frequency = JMR3927_TIMER_CLK;
#ifdef USE_RTC_DS1742
if (jmr3927_have_nvram()) {
rtc_ds1742_init(JMR3927_IOC_NVRAMB_ADDR);
@@ -183,12 +191,8 @@ static void __init jmr3927_time_init(void)
#endif
}
-unsigned long jmr3927_do_gettimeoffset(void);
-
void __init plat_timer_setup(struct irqaction *irq)
{
- do_gettimeoffset = jmr3927_do_gettimeoffset;
-
jmr3927_tmrptr->cpra = JMR3927_TIMER_CLK / HZ;
jmr3927_tmrptr->itmr = TXx927_TMTITMR_TIIE | TXx927_TMTITMR_TZCE;
jmr3927_tmrptr->ccdr = JMR3927_TIMER_CCD;
@@ -200,34 +204,6 @@ void __init plat_timer_setup(struct irqaction *irq)
#define USECS_PER_JIFFY (1000000/HZ)
-unsigned long jmr3927_do_gettimeoffset(void)
-{
- unsigned long count;
- unsigned long res = 0;
-
- /* MUST read TRR before TISR. */
- count = jmr3927_tmrptr->trr;
-
- if (jmr3927_tmrptr->tisr & TXx927_TMTISR_TIIS) {
- /* timer interrupt is pending. use Max value. */
- res = USECS_PER_JIFFY - 1;
- } else {
- /* convert to usec */
- /* res = count / (JMR3927_TIMER_CLK / 1000000); */
- res = (count << 7) / ((JMR3927_TIMER_CLK << 7) / 1000000);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY-1;
- }
-
- return res;
-}
-
-
//#undef DO_WRITE_THROUGH
#define DO_WRITE_THROUGH
#define DO_ENABLE_CACHE
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
index debe86c2f69..e535f86efa2 100644
--- a/arch/mips/kernel/time.c
+++ b/arch/mips/kernel/time.c
@@ -11,6 +11,7 @@
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
+#include <linux/clocksource.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
@@ -67,15 +68,9 @@ int (*rtc_mips_set_time)(unsigned long) = null_rtc_set_time;
int (*rtc_mips_set_mmss)(unsigned long);
-/* usecs per counter cycle, shifted to left by 32 bits */
-static unsigned int sll32_usecs_per_cycle;
-
/* how many counter cycles in a jiffy */
static unsigned long cycles_per_jiffy __read_mostly;
-/* Cycle counter value at the previous timer interrupt.. */
-static unsigned int timerhi, timerlo;
-
/* expirelo is the count value for next CPU timer interrupt */
static unsigned int expirelo;
@@ -93,7 +88,7 @@ static unsigned int null_hpt_read(void)
return 0;
}
-static void null_hpt_init(unsigned int count)
+static void __init null_hpt_init(void)
{
/* nothing */
}
@@ -128,186 +123,18 @@ static unsigned int c0_hpt_read(void)
return read_c0_count();
}
-/* For use solely as a high precision timer. */
-static void c0_hpt_init(unsigned int count)
-{
- write_c0_count(read_c0_count() - count);
-}
-
/* For use both as a high precision timer and an interrupt source. */
-static void c0_hpt_timer_init(unsigned int count)
+static void __init c0_hpt_timer_init(void)
{
- count = read_c0_count() - count;
- expirelo = (count / cycles_per_jiffy + 1) * cycles_per_jiffy;
- write_c0_count(expirelo - cycles_per_jiffy);
+ expirelo = read_c0_count() + cycles_per_jiffy;
write_c0_compare(expirelo);
- write_c0_count(count);
}
int (*mips_timer_state)(void);
void (*mips_timer_ack)(void);
unsigned int (*mips_hpt_read)(void);
-void (*mips_hpt_init)(unsigned int);
-
-/*
- * Gettimeoffset routines. These routines returns the time duration
- * since last timer interrupt in usecs.
- *
- * If the exact CPU counter frequency is known, use fixed_rate_gettimeoffset.
- * Otherwise use calibrate_gettimeoffset()
- *
- * If the CPU does not have the counter register, you can either supply
- * your own gettimeoffset() routine, or use null_gettimeoffset(), which
- * gives the same resolution as HZ.
- */
-
-static unsigned long null_gettimeoffset(void)
-{
- return 0;
-}
-
-
-/* The function pointer to one of the gettimeoffset funcs. */
-unsigned long (*do_gettimeoffset)(void) = null_gettimeoffset;
-
-
-static unsigned long fixed_rate_gettimeoffset(void)
-{
- u32 count;
- unsigned long res;
-
- /* Get last timer tick in absolute kernel time */
- count = mips_hpt_read();
-
- /* .. relative to previous jiffy (32 bits is enough) */
- count -= timerlo;
-
- __asm__("multu %1,%2"
- : "=h" (res)
- : "r" (count), "r" (sll32_usecs_per_cycle)
- : "lo", GCC_REG_ACCUM);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY - 1;
-
- return res;
-}
-
-
-/*
- * Cached "1/(clocks per usec) * 2^32" value.
- * It has to be recalculated once each jiffy.
- */
-static unsigned long cached_quotient;
-
-/* Last jiffy when calibrate_divXX_gettimeoffset() was called. */
-static unsigned long last_jiffies;
-
-/*
- * This is moved from dec/time.c:do_ioasic_gettimeoffset() by Maciej.
- */
-static unsigned long calibrate_div32_gettimeoffset(void)
-{
- u32 count;
- unsigned long res, tmp;
- unsigned long quotient;
-
- tmp = jiffies;
-
- quotient = cached_quotient;
-
- if (last_jiffies != tmp) {
- last_jiffies = tmp;
- if (last_jiffies != 0) {
- unsigned long r0;
- do_div64_32(r0, timerhi, timerlo, tmp);
- do_div64_32(quotient, USECS_PER_JIFFY,
- USECS_PER_JIFFY_FRAC, r0);
- cached_quotient = quotient;
- }
- }
-
- /* Get last timer tick in absolute kernel time */
- count = mips_hpt_read();
-
- /* .. relative to previous jiffy (32 bits is enough) */
- count -= timerlo;
-
- __asm__("multu %1,%2"
- : "=h" (res)
- : "r" (count), "r" (quotient)
- : "lo", GCC_REG_ACCUM);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY - 1;
-
- return res;
-}
-
-static unsigned long calibrate_div64_gettimeoffset(void)
-{
- u32 count;
- unsigned long res, tmp;
- unsigned long quotient;
-
- tmp = jiffies;
-
- quotient = cached_quotient;
-
- if (last_jiffies != tmp) {
- last_jiffies = tmp;
- if (last_jiffies) {
- unsigned long r0;
- __asm__(".set push\n\t"
- ".set mips3\n\t"
- "lwu %0,%3\n\t"
- "dsll32 %1,%2,0\n\t"
- "or %1,%1,%0\n\t"
- "ddivu $0,%1,%4\n\t"
- "mflo %1\n\t"
- "dsll32 %0,%5,0\n\t"
- "or %0,%0,%6\n\t"
- "ddivu $0,%0,%1\n\t"
- "mflo %0\n\t"
- ".set pop"
- : "=&r" (quotient), "=&r" (r0)
- : "r" (timerhi), "m" (timerlo),
- "r" (tmp), "r" (USECS_PER_JIFFY),
- "r" (USECS_PER_JIFFY_FRAC)
- : "hi", "lo", GCC_REG_ACCUM);
- cached_quotient = quotient;
- }
- }
-
- /* Get last timer tick in absolute kernel time */
- count = mips_hpt_read();
-
- /* .. relative to previous jiffy (32 bits is enough) */
- count -= timerlo;
-
- __asm__("multu %1,%2"
- : "=h" (res)
- : "r" (count), "r" (quotient)
- : "lo", GCC_REG_ACCUM);
-
- /*
- * Due to possible jiffies inconsistencies, we need to check
- * the result so that we'll get a timer that is monotonic.
- */
- if (res >= USECS_PER_JIFFY)
- res = USECS_PER_JIFFY - 1;
-
- return res;
-}
-
+void (*mips_hpt_init)(void) __initdata = null_hpt_init;
+unsigned int mips_hpt_mask = 0xffffffff;
/* last time when xtime and rtc are sync'ed up */
static long last_rtc_update;
@@ -334,18 +161,10 @@ void local_timer_interrupt(int irq, void *dev_id)
*/
irqreturn_t timer_interrupt(int irq, void *dev_id)
{
- unsigned long j;
- unsigned int count;
-
write_seqlock(&xtime_lock);
- count = mips_hpt_read();
mips_timer_ack();
- /* Update timerhi/timerlo for intra-jiffy calibration. */
- timerhi += count < timerlo; /* Wrap around */
- timerlo = count;
-
/*
* call the generic timer interrupt handling
*/
@@ -368,47 +187,6 @@ irqreturn_t timer_interrupt(int irq, void *dev_id)
}
}
- /*
- * If jiffies has overflown in this timer_interrupt, we must
- * update the timer[hi]/[lo] to make fast gettimeoffset funcs
- * quotient calc still valid. -arca
- *
- * The first timer interrupt comes late as interrupts are
- * enabled long after timers are initialized. Therefore the
- * high precision timer is fast, leading to wrong gettimeoffset()
- * calculations. We deal with it by setting it based on the
- * number of its ticks between the second and the third interrupt.
- * That is still somewhat imprecise, but it's a good estimate.
- * --macro
- */
- j = jiffies;
- if (j < 4) {
- static unsigned int prev_count;
- static int hpt_initialized;
-
- switch (j) {
- case 0:
- timerhi = timerlo = 0;
- mips_hpt_init(count);
- break;
- case 2:
- prev_count = count;
- break;
- case 3:
- if (!hpt_initialized) {
- unsigned int c3 = 3 * (count - prev_count);
-
- timerhi = 0;
- timerlo = c3;
- mips_hpt_init(count - c3);
- hpt_initialized = 1;
- }
- break;
- default:
- break;
- }
- }
-
write_sequnlock(&xtime_lock);
/*
@@ -476,12 +254,11 @@ asmlinkage void ll_local_timer_interrupt(int irq)
* 1) board_time_init() -
* a) (optional) set up RTC routines,
* b) (optional) calibrate and set the mips_hpt_frequency
- * (only needed if you intended to use fixed_rate_gettimeoffset
- * or use cpu counter as timer interrupt source)
+ * (only needed if you intended to use cpu counter as timer interrupt
+ * source)
* 2) setup xtime based on rtc_mips_get_time().
- * 3) choose a appropriate gettimeoffset routine.
- * 4) calculate a couple of cached variables for later usage
- * 5) plat_timer_setup() -
+ * 3) calculate a couple of cached variables for later usage
+ * 4) plat_timer_setup() -
* a) (optional) over-write any choices made above by time_init().
* b) machine specific code should setup the timer irqaction.
* c) enable the timer interrupt
@@ -533,13 +310,48 @@ static unsigned int __init calibrate_hpt(void)
} while (--i);
hpt_end = mips_hpt_read();
- hpt_count = hpt_end - hpt_start;
+ hpt_count = (hpt_end - hpt_start) & mips_hpt_mask;
hz = HZ;
frequency = (u64)hpt_count * (u64)hz;
return frequency >> log_2_loops;
}
+static cycle_t read_mips_hpt(void)
+{
+ return (cycle_t)mips_hpt_read();
+}
+
+static struct clocksource clocksource_mips = {
+ .name = "MIPS",
+ .read = read_mips_hpt,
+ .is_continuous = 1,
+};
+
+static void __init init_mips_clocksource(void)
+{
+ u64 temp;
+ u32 shift;
+
+ if (!mips_hpt_frequency || mips_hpt_read == null_hpt_read)
+ return;
+
+ /* Calclate a somewhat reasonable rating value */
+ clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000;
+ /* Find a shift value */
+ for (shift = 32; shift > 0; shift--) {
+ temp = (u64) NSEC_PER_SEC << shift;
+ do_div(temp, mips_hpt_frequency);
+ if ((temp >> 32) == 0)
+ break;
+ }
+ clocksource_mips.shift = shift;
+ clocksource_mips.mult = (u32)temp;
+ clocksource_mips.mask = mips_hpt_mask;
+
+ clocksource_register(&clocksource_mips);
+}
+
void __init time_init(void)
{
if (board_time_init)
@@ -555,41 +367,21 @@ void __init time_init(void)
-xtime.tv_sec, -xtime.tv_nsec);
/* Choose appropriate high precision timer routines. */
- if (!cpu_has_counter && !mips_hpt_read) {
+ if (!cpu_has_counter && !mips_hpt_read)
/* No high precision timer -- sorry. */
mips_hpt_read = null_hpt_read;
- mips_hpt_init = null_hpt_init;
- } else if (!mips_hpt_frequency && !mips_timer_state) {
+ else if (!mips_hpt_frequency && !mips_timer_state) {
/* A high precision timer of unknown frequency. */
- if (!mips_hpt_read) {
+ if (!mips_hpt_read)
/* No external high precision timer -- use R4k. */
mips_hpt_read = c0_hpt_read;
- mips_hpt_init = c0_hpt_init;
- }
-
- if (cpu_has_mips32r1 || cpu_has_mips32r2 ||
- (current_cpu_data.isa_level == MIPS_CPU_ISA_I) ||
- (current_cpu_data.isa_level == MIPS_CPU_ISA_II))
- /*
- * We need to calibrate the counter but we don't have
- * 64-bit division.
- */
- do_gettimeoffset = calibrate_div32_gettimeoffset;
- else
- /*
- * We need to calibrate the counter but we *do* have
- * 64-bit division.
- */
- do_gettimeoffset = calibrate_div64_gettimeoffset;
} else {
/* We know counter frequency. Or we can get it. */
if (!mips_hpt_read) {
/* No external high precision timer -- use R4k. */
mips_hpt_read = c0_hpt_read;
- if (mips_timer_state)
- mips_hpt_init = c0_hpt_init;
- else {
+ if (!mips_timer_state) {
/* No external timer interrupt -- use R4k. */
mips_hpt_init = c0_hpt_timer_init;
mips_timer_ack = c0_timer_ack;
@@ -598,16 +390,9 @@ void __init time_init(void)
if (!mips_hpt_frequency)
mips_hpt_frequency = calibrate_hpt();
- do_gettimeoffset = fixed_rate_gettimeoffset;
-
/* Calculate cache parameters. */
cycles_per_jiffy = (mips_hpt_frequency + HZ / 2) / HZ;
- /* sll32_usecs_per_cycle = 10^6 * 2^32 / mips_counter_freq */
- do_div64_32(sll32_usecs_per_cycle,
- 1000000, mips_hpt_frequency / 2,
- mips_hpt_frequency);
-
/* Report the high precision timer rate for a reference. */
printk("Using %u.%03u MHz high precision timer.\n",
((mips_hpt_frequency + 500) / 1000) / 1000,
@@ -619,7 +404,7 @@ void __init time_init(void)
mips_timer_ack = null_timer_ack;
/* This sets up the high precision timer for the first interrupt. */
- mips_hpt_init(mips_hpt_read());
+ mips_hpt_init();
/*
* Call board specific timer interrupt setup.
@@ -633,6 +418,8 @@ void __init time_init(void)
* is not invoked accidentally.
*/
plat_timer_setup(&timer_irqaction);
+
+ init_mips_clocksource();
}
#define FEBRUARY 2
diff --git a/arch/mips/philips/pnx8550/common/time.c b/arch/mips/philips/pnx8550/common/time.c
index 0af655b1f33..65c440e8480 100644
--- a/arch/mips/philips/pnx8550/common/time.c
+++ b/arch/mips/philips/pnx8550/common/time.c
@@ -41,8 +41,8 @@ extern unsigned int mips_hpt_frequency;
* 1) board_time_init() -
* a) (optional) set up RTC routines,
* b) (optional) calibrate and set the mips_hpt_frequency
- * (only needed if you intended to use fixed_rate_gettimeoffset
- * or use cpu counter as timer interrupt source)
+ * (only needed if you intended to use cpu counter as timer interrupt
+ * source)
*/
void pnx8550_time_init(void)
diff --git a/arch/mips/pmc-sierra/yosemite/smp.c b/arch/mips/pmc-sierra/yosemite/smp.c
index 65fa3a23ea5..3cc0436db6c 100644
--- a/arch/mips/pmc-sierra/yosemite/smp.c
+++ b/arch/mips/pmc-sierra/yosemite/smp.c
@@ -3,9 +3,7 @@
#include <asm/pmon.h>
#include <asm/titan_dep.h>
-
-extern unsigned int (*mips_hpt_read)(void);
-extern void (*mips_hpt_init)(unsigned int);
+#include <asm/time.h>
#define LAUNCHSTACK_SIZE 256
@@ -101,7 +99,7 @@ void prom_cpus_done(void)
*/
void prom_init_secondary(void)
{
- mips_hpt_init(mips_hpt_read());
+ mips_hpt_init();
set_c0_status(ST0_CO | ST0_IE | ST0_IM);
}
diff --git a/arch/mips/sgi-ip27/ip27-timer.c b/arch/mips/sgi-ip27/ip27-timer.c
index 4e870fc4469..c965705f342 100644
--- a/arch/mips/sgi-ip27/ip27-timer.c
+++ b/arch/mips/sgi-ip27/ip27-timer.c
@@ -134,13 +134,6 @@ again:
irq_exit();
}
-unsigned long ip27_do_gettimeoffset(void)
-{
- unsigned long ct_cur1;
- ct_cur1 = REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT) + CYCLES_PER_JIFFY;
- return (ct_cur1 - ct_cur[0]) * NSEC_PER_CYCLE / 1000;
-}
-
/* Includes for ioc3_init(). */
#include <asm/sn/types.h>
#include <asm/sn/sn0/addrs.h>
@@ -248,12 +241,17 @@ void __init plat_timer_setup(struct irqaction *irq)
setup_irq(irqno, &rt_irqaction);
}
+static unsigned int ip27_hpt_read(void)
+{
+ return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
+}
+
void __init ip27_time_init(void)
{
+ mips_hpt_read = ip27_hpt_read;
+ mips_hpt_frequency = CYCLES_PER_SEC;
xtime.tv_sec = get_m48t35_time();
xtime.tv_nsec = 0;
-
- do_gettimeoffset = ip27_do_gettimeoffset;
}
void __init cpu_time_init(void)
diff --git a/arch/mips/sibyte/bcm1480/time.c b/arch/mips/sibyte/bcm1480/time.c
index bf12af46132..e136bde5248 100644
--- a/arch/mips/sibyte/bcm1480/time.c
+++ b/arch/mips/sibyte/bcm1480/time.c
@@ -47,6 +47,12 @@
#define IMR_IP3_VAL K_BCM1480_INT_MAP_I1
#define IMR_IP4_VAL K_BCM1480_INT_MAP_I2
+#ifdef CONFIG_SIMULATION
+#define BCM1480_HPT_VALUE 50000
+#else
+#define BCM1480_HPT_VALUE 1000000
+#endif
+
extern int bcm1480_steal_irq(int irq);
void bcm1480_time_init(void)
@@ -59,11 +65,6 @@ void bcm1480_time_init(void)
BUG();
}
- if (!cpu) {
- /* Use our own gettimeoffset() routine */
- do_gettimeoffset = bcm1480_gettimeoffset;
- }
-
bcm1480_mask_irq(cpu, irq);
/* Map the timer interrupt to ip[4] of this cpu */
@@ -74,11 +75,7 @@ void bcm1480_time_init(void)
/* Disable the timer and set up the count */
__raw_writeq(0, IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
__raw_writeq(
-#ifndef CONFIG_SIMULATION
- 1000000/HZ
-#else
- 50000/HZ
-#endif
+ BCM1480_HPT_VALUE/HZ
, IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)));
/* Set the timer running */
@@ -122,16 +119,16 @@ void bcm1480_timer_interrupt(void)
}
}
-/*
- * We use our own do_gettimeoffset() instead of the generic one,
- * because the generic one does not work for SMP case.
- * In addition, since we use general timer 0 for system time,
- * we can get accurate intra-jiffy offset without calibration.
- */
-unsigned long bcm1480_gettimeoffset(void)
+static unsigned int bcm1480_hpt_read(void)
{
+ /* We assume this function is called xtime_lock held. */
unsigned long count =
__raw_readq(IOADDR(A_SCD_TIMER_REGISTER(0, R_SCD_TIMER_CNT)));
+ return (jiffies + 1) * (BCM1480_HPT_VALUE / HZ) - count;
+}
- return 1000000/HZ - count;
+void __init bcm1480_hpt_setup(void)
+{
+ mips_hpt_read = bcm1480_hpt_read;
+ mips_hpt_frequency = BCM1480_HPT_VALUE;
}
diff --git a/arch/mips/sibyte/sb1250/time.c b/arch/mips/sibyte/sb1250/time.c
index 0ccf1796dd7..bcb74f2c194 100644
--- a/arch/mips/sibyte/sb1250/time.c
+++ b/arch/mips/sibyte/sb1250/time.c
@@ -47,15 +47,11 @@
#define SB1250_HPT_NUM 3
#define SB1250_HPT_VALUE M_SCD_TIMER_CNT /* max value */
-#define SB1250_HPT_SHIFT ((sizeof(unsigned int)*8)-V_SCD_TIMER_WIDTH)
extern int sb1250_steal_irq(int irq);
static unsigned int sb1250_hpt_read(void);
-static void sb1250_hpt_init(unsigned int);
-
-static unsigned int hpt_offset;
void __init sb1250_hpt_setup(void)
{
@@ -69,13 +65,9 @@ void __init sb1250_hpt_setup(void)
__raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM, R_SCD_TIMER_CFG)));
- /*
- * we need to fill 32 bits, so just use the upper 23 bits and pretend
- * the timer is going 512Mhz instead of 1Mhz
- */
- mips_hpt_frequency = V_SCD_TIMER_FREQ << SB1250_HPT_SHIFT;
- mips_hpt_init = sb1250_hpt_init;
+ mips_hpt_frequency = V_SCD_TIMER_FREQ;
mips_hpt_read = sb1250_hpt_read;
+ mips_hpt_mask = M_SCD_TIMER_INIT;
}
}
@@ -149,11 +141,7 @@ void sb1250_timer_interrupt(void)
/*
* The HPT is free running from SB1250_HPT_VALUE down to 0 then starts over
- * again. There's no easy way to set to a specific value so store init value
- * in hpt_offset and subtract each time.
- *
- * Note: Timer isn't full 32bits so shift it into the upper part making
- * it appear to run at a higher frequency.
+ * again.
*/
static unsigned int sb1250_hpt_read(void)
{
@@ -161,13 +149,5 @@ static unsigned int sb1250_hpt_read(void)
count = G_SCD_TIMER_CNT(__raw_readq(IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM, R_SCD_TIMER_CNT))));
- count = (SB1250_HPT_VALUE - count) << SB1250_HPT_SHIFT;
-
- return count - hpt_offset;
-}
-
-static void sb1250_hpt_init(unsigned int count)
-{
- hpt_offset = count;
- return;
+ return SB1250_HPT_VALUE - count;
}
diff --git a/include/asm-mips/div64.h b/include/asm-mips/div64.h
index 5f7dcf5452e..d107832de1b 100644
--- a/include/asm-mips/div64.h
+++ b/include/asm-mips/div64.h
@@ -83,27 +83,6 @@
#if (_MIPS_SZLONG == 64)
/*
- * Don't use this one in new code
- */
-#define do_div64_32(res, high, low, base) ({ \
- unsigned int __quot, __mod; \
- unsigned long __div; \
- unsigned int __low, __high, __base; \
- \
- __high = (high); \
- __low = (low); \
- __div = __high; \
- __div = __div << 32 | __low; \
- __base = (base); \
- \
- __mod = __div % __base; \
- __div = __div / __base; \
- \
- __quot = __div; \
- (res) = __quot; \
- __mod; })
-
-/*
* Hey, we're already 64-bit, no
* need to play games..
*/
diff --git a/include/asm-mips/sibyte/sb1250.h b/include/asm-mips/sibyte/sb1250.h
index b09e16c93ca..2ba6988ddc8 100644
--- a/include/asm-mips/sibyte/sb1250.h
+++ b/include/asm-mips/sibyte/sb1250.h
@@ -51,8 +51,8 @@ extern void sb1250_mask_irq(int cpu, int irq);
extern void sb1250_unmask_irq(int cpu, int irq);
extern void sb1250_smp_finish(void);
+extern void bcm1480_hpt_setup(void);
extern void bcm1480_time_init(void);
-extern unsigned long bcm1480_gettimeoffset(void);
extern void bcm1480_mask_irq(int cpu, int irq);
extern void bcm1480_unmask_irq(int cpu, int irq);
extern void bcm1480_smp_finish(void);
diff --git a/include/asm-mips/time.h b/include/asm-mips/time.h
index 28512ba2266..625acd337bc 100644
--- a/include/asm-mips/time.h
+++ b/include/asm-mips/time.h
@@ -48,7 +48,8 @@ extern void (*mips_timer_ack)(void);
* If mips_hpt_read is NULL, an R4k-compatible timer setup is attempted.
*/
extern unsigned int (*mips_hpt_read)(void);
-extern void (*mips_hpt_init)(unsigned int);
+extern void (*mips_hpt_init)(void);
+extern unsigned int mips_hpt_mask;
/*
* to_tm() converts system time back to (year, mon, day, hour, min, sec).
@@ -58,13 +59,6 @@ extern void (*mips_hpt_init)(unsigned int);
extern void to_tm(unsigned long tim, struct rtc_time *tm);
/*
- * do_gettimeoffset(). By default, this func pointer points to
- * do_null_gettimeoffset(), which leads to the same resolution as HZ.
- * Higher resolution versions are available, which give ~1us resolution.
- */
-extern unsigned long (*do_gettimeoffset)(void);
-
-/*
* high-level timer interrupt routines.
*/
extern irqreturn_t timer_interrupt(int irq, void *dev_id);