diff options
Diffstat (limited to 'drivers/clocksource/mips-gic-timer.c')
-rw-r--r-- | drivers/clocksource/mips-gic-timer.c | 59 |
1 files changed, 50 insertions, 9 deletions
diff --git a/drivers/clocksource/mips-gic-timer.c b/drivers/clocksource/mips-gic-timer.c index b3ae38f36720..7907b740497a 100644 --- a/drivers/clocksource/mips-gic-timer.c +++ b/drivers/clocksource/mips-gic-timer.c @@ -19,6 +19,7 @@ static DEFINE_PER_CPU(struct clock_event_device, gic_clockevent_device); static int gic_timer_irq; static unsigned int gic_frequency; +static unsigned int gic_count_width; static bool __read_mostly gic_clock_unstable; static void gic_clocksource_unstable(char *reason); @@ -165,6 +166,37 @@ static u64 gic_hpt_read(struct clocksource *cs) return gic_read_count(); } +static u64 gic_hpt_read_multicluster(struct clocksource *cs) +{ + unsigned int hi, hi2, lo; + u64 count; + + mips_cm_lock_other(0, 0, 0, CM_GCR_Cx_OTHER_BLOCK_GLOBAL); + + if (mips_cm_is64) { + count = read_gic_redir_counter(); + goto out; + } + + hi = read_gic_redir_counter_32h(); + while (true) { + lo = read_gic_redir_counter_32l(); + + /* If hi didn't change then lo didn't wrap & we're done */ + hi2 = read_gic_redir_counter_32h(); + if (hi2 == hi) + break; + + /* Otherwise, repeat with the latest hi value */ + hi = hi2; + } + + count = (((u64)hi) << 32) + lo; +out: + mips_cm_unlock_other(); + return count; +} + static struct clocksource gic_clocksource = { .name = "GIC", .read = gic_hpt_read, @@ -186,18 +218,26 @@ static void gic_clocksource_unstable(char *reason) static int __init __gic_clocksource_init(void) { - unsigned int count_width; int ret; /* Set clocksource mask. */ - count_width = read_gic_config() & GIC_CONFIG_COUNTBITS; - count_width >>= __ffs(GIC_CONFIG_COUNTBITS); - count_width *= 4; - count_width += 32; - gic_clocksource.mask = CLOCKSOURCE_MASK(count_width); + gic_count_width = read_gic_config() & GIC_CONFIG_COUNTBITS; + gic_count_width >>= __ffs(GIC_CONFIG_COUNTBITS); + gic_count_width *= 4; + gic_count_width += 32; + gic_clocksource.mask = CLOCKSOURCE_MASK(gic_count_width); /* Calculate a somewhat reasonable rating value. */ - gic_clocksource.rating = 200 + gic_frequency / 10000000; + if (mips_cm_revision() >= CM_REV_CM3 || !IS_ENABLED(CONFIG_CPU_FREQ)) + gic_clocksource.rating = 300; /* Good when frequecy is stable */ + else + gic_clocksource.rating = 200; + gic_clocksource.rating += clamp(gic_frequency / 10000000, 0, 99); + + if (mips_cps_multicluster_cpus()) { + gic_clocksource.read = &gic_hpt_read_multicluster; + gic_clocksource.vdso_clock_mode = VDSO_CLOCKMODE_NONE; + } ret = clocksource_register_hz(&gic_clocksource, gic_frequency); if (ret < 0) @@ -257,10 +297,11 @@ static int __init gic_clocksource_of_init(struct device_node *node) * stable CPU frequency or on the platforms with CM3 and CPU frequency * change performed by the CPC core clocks divider. */ - if (mips_cm_revision() >= CM_REV_CM3 || !IS_ENABLED(CONFIG_CPU_FREQ)) { + if ((mips_cm_revision() >= CM_REV_CM3 || !IS_ENABLED(CONFIG_CPU_FREQ)) && + !mips_cps_multicluster_cpus()) { sched_clock_register(mips_cm_is64 ? gic_read_count_64 : gic_read_count_2x32, - 64, gic_frequency); + gic_count_width, gic_frequency); } return 0; |