| Message ID | 1359143205-20279-2-git-send-email-mark.langsdorf@calxeda.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Friday, January 25, 2013 01:46:42 PM Mark Langsdorf wrote: > From: Rob Herring <rob.herring@calxeda.com> > > Move clk setup to twd_local_timer_common_register and rely on > twd_timer_rate being 0 to force calibration if there is no clock. > Remove common_setup_called as it is no longer needed. > > Signed-off-by: Rob Herring <rob.herring@calxeda.com> > Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com> Russell, is this fine with you? Rafael > --- > Changes from v10 > Reworked to simplify the logic as suggested by Russell King. > Changes from v9 > Updated to work with 3.8 kernel. > Changes from v4, v5, v6, v7, v8 > None. > Changes from v3 > No longer setting *clk to NULL in twd_get_clock(). > Changes from v2 > Turned the check for the node pointer into an if-then-else statement. > Removed the second, redundant clk_get_rate. > Changes from v1 > None. > > arch/arm/kernel/smp_twd.c | 53 +++++++++++++++++------------------------------ > 1 file changed, 19 insertions(+), 34 deletions(-) > > diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c > index 49f335d..ae0c7bb 100644 > --- a/arch/arm/kernel/smp_twd.c > +++ b/arch/arm/kernel/smp_twd.c > @@ -31,7 +31,6 @@ static void __iomem *twd_base; > > static struct clk *twd_clk; > static unsigned long twd_timer_rate; > -static bool common_setup_called; > static DEFINE_PER_CPU(bool, percpu_setup_called); > > static struct clock_event_device __percpu **twd_evt; > @@ -239,25 +238,28 @@ static irqreturn_t twd_handler(int irq, void *dev_id) > return IRQ_NONE; > } > > -static struct clk *twd_get_clock(void) > +static void twd_get_clock(struct device_node *np) > { > - struct clk *clk; > int err; > > - clk = clk_get_sys("smp_twd", NULL); > - if (IS_ERR(clk)) { > - pr_err("smp_twd: clock not found: %d\n", (int)PTR_ERR(clk)); > - return clk; > + if (np) > + twd_clk = of_clk_get(np, 0); > + else > + twd_clk = clk_get_sys("smp_twd", NULL); > + > + if (IS_ERR(twd_clk)) { > + pr_err("smp_twd: clock not found %d\n", (int) PTR_ERR(twd_clk)); > + return; > } > > - err = clk_prepare_enable(clk); > + err = clk_prepare_enable(twd_clk); > if (err) { > pr_err("smp_twd: clock failed to prepare+enable: %d\n", err); > - clk_put(clk); > - return ERR_PTR(err); > + clk_put(twd_clk); > + return; > } > > - return clk; > + twd_timer_rate = clk_get_rate(twd_clk); > } > > /* > @@ -280,26 +282,7 @@ static int __cpuinit twd_timer_setup(struct clock_event_device *clk) > } > per_cpu(percpu_setup_called, cpu) = true; > > - /* > - * This stuff only need to be done once for the entire TWD cluster > - * during the runtime of the system. > - */ > - if (!common_setup_called) { > - twd_clk = twd_get_clock(); > - > - /* > - * We use IS_ERR_OR_NULL() here, because if the clock stubs > - * are active we will get a valid clk reference which is > - * however NULL and will return the rate 0. In that case we > - * need to calibrate the rate instead. > - */ > - if (!IS_ERR_OR_NULL(twd_clk)) > - twd_timer_rate = clk_get_rate(twd_clk); > - else > - twd_calibrate_rate(); > - > - common_setup_called = true; > - } > + twd_calibrate_rate(); > > /* > * The following is done once per CPU the first time .setup() is > @@ -330,7 +313,7 @@ static struct local_timer_ops twd_lt_ops __cpuinitdata = { > .stop = twd_timer_stop, > }; > > -static int __init twd_local_timer_common_register(void) > +static int __init twd_local_timer_common_register(struct device_node *np) > { > int err; > > @@ -350,6 +333,8 @@ static int __init twd_local_timer_common_register(void) > if (err) > goto out_irq; > > + twd_get_clock(np); > + > return 0; > > out_irq: > @@ -373,7 +358,7 @@ int __init twd_local_timer_register(struct twd_local_timer *tlt) > if (!twd_base) > return -ENOMEM; > > - return twd_local_timer_common_register(); > + return twd_local_timer_common_register(NULL); > } > > #ifdef CONFIG_OF > @@ -405,7 +390,7 @@ void __init twd_local_timer_of_register(void) > goto out; > } > > - err = twd_local_timer_common_register(); > + err = twd_local_timer_common_register(np); > > out: > WARN(err, "twd_local_timer_of_register failed (%d)\n", err); >
On Fri, Jan 25, 2013 at 10:03:05PM +0100, Rafael J. Wysocki wrote: > On Friday, January 25, 2013 01:46:42 PM Mark Langsdorf wrote: > > From: Rob Herring <rob.herring@calxeda.com> > > > > Move clk setup to twd_local_timer_common_register and rely on > > twd_timer_rate being 0 to force calibration if there is no clock. > > Remove common_setup_called as it is no longer needed. > > > > Signed-off-by: Rob Herring <rob.herring@calxeda.com> > > Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com> > > Russell, is this fine with you? Looks fine to me, though I had to check twd_calibrate_rate() to make sure it wouldn't run if the twd_timer_rate was non-zero. If you want an acked-by: Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Thanks.
On Friday, January 25, 2013 09:40:00 PM Russell King - ARM Linux wrote: > On Fri, Jan 25, 2013 at 10:03:05PM +0100, Rafael J. Wysocki wrote: > > On Friday, January 25, 2013 01:46:42 PM Mark Langsdorf wrote: > > > From: Rob Herring <rob.herring@calxeda.com> > > > > > > Move clk setup to twd_local_timer_common_register and rely on > > > twd_timer_rate being 0 to force calibration if there is no clock. > > > Remove common_setup_called as it is no longer needed. > > > > > > Signed-off-by: Rob Herring <rob.herring@calxeda.com> > > > Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com> > > > > Russell, is this fine with you? > > Looks fine to me, though I had to check twd_calibrate_rate() to make > sure it wouldn't run if the twd_timer_rate was non-zero. > > If you want an acked-by: > > Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> I will, thanks a lot! Rafael
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index 49f335d..ae0c7bb 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -31,7 +31,6 @@ static void __iomem *twd_base; static struct clk *twd_clk; static unsigned long twd_timer_rate; -static bool common_setup_called; static DEFINE_PER_CPU(bool, percpu_setup_called); static struct clock_event_device __percpu **twd_evt; @@ -239,25 +238,28 @@ static irqreturn_t twd_handler(int irq, void *dev_id) return IRQ_NONE; } -static struct clk *twd_get_clock(void) +static void twd_get_clock(struct device_node *np) { - struct clk *clk; int err; - clk = clk_get_sys("smp_twd", NULL); - if (IS_ERR(clk)) { - pr_err("smp_twd: clock not found: %d\n", (int)PTR_ERR(clk)); - return clk; + if (np) + twd_clk = of_clk_get(np, 0); + else + twd_clk = clk_get_sys("smp_twd", NULL); + + if (IS_ERR(twd_clk)) { + pr_err("smp_twd: clock not found %d\n", (int) PTR_ERR(twd_clk)); + return; } - err = clk_prepare_enable(clk); + err = clk_prepare_enable(twd_clk); if (err) { pr_err("smp_twd: clock failed to prepare+enable: %d\n", err); - clk_put(clk); - return ERR_PTR(err); + clk_put(twd_clk); + return; } - return clk; + twd_timer_rate = clk_get_rate(twd_clk); } /* @@ -280,26 +282,7 @@ static int __cpuinit twd_timer_setup(struct clock_event_device *clk) } per_cpu(percpu_setup_called, cpu) = true; - /* - * This stuff only need to be done once for the entire TWD cluster - * during the runtime of the system. - */ - if (!common_setup_called) { - twd_clk = twd_get_clock(); - - /* - * We use IS_ERR_OR_NULL() here, because if the clock stubs - * are active we will get a valid clk reference which is - * however NULL and will return the rate 0. In that case we - * need to calibrate the rate instead. - */ - if (!IS_ERR_OR_NULL(twd_clk)) - twd_timer_rate = clk_get_rate(twd_clk); - else - twd_calibrate_rate(); - - common_setup_called = true; - } + twd_calibrate_rate(); /* * The following is done once per CPU the first time .setup() is @@ -330,7 +313,7 @@ static struct local_timer_ops twd_lt_ops __cpuinitdata = { .stop = twd_timer_stop, }; -static int __init twd_local_timer_common_register(void) +static int __init twd_local_timer_common_register(struct device_node *np) { int err; @@ -350,6 +333,8 @@ static int __init twd_local_timer_common_register(void) if (err) goto out_irq; + twd_get_clock(np); + return 0; out_irq: @@ -373,7 +358,7 @@ int __init twd_local_timer_register(struct twd_local_timer *tlt) if (!twd_base) return -ENOMEM; - return twd_local_timer_common_register(); + return twd_local_timer_common_register(NULL); } #ifdef CONFIG_OF @@ -405,7 +390,7 @@ void __init twd_local_timer_of_register(void) goto out; } - err = twd_local_timer_common_register(); + err = twd_local_timer_common_register(np); out: WARN(err, "twd_local_timer_of_register failed (%d)\n", err);