| Message ID | 1419688528-760-2-git-send-email-robert.jarzmik@free.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Quoting Robert Jarzmik (2014-12-27 05:55:25) > Since pxa clocks were ported to the clock framework, an ordering issue > appears between clocks and clocksource initialization. As a consequence, > the pxa timer clock cannot be acquired in pxa_timer, and is disabled by > clock framework because it is "unused". > > The ordering issue is that in the kernel boot sequence : > start_kernel() > ... > time_init() > -> pxa_timer() > -> here the clocksource is initialized > ... > rest_init() > kernel_init() > initcalls > -> here the clocks are initialized > > In the current sequence, the clocks are initialized way after pxa_timer, > which cannot acquire the OSTIMER0 clock. > > To solve this issue, the clocks initialization is moved to pxa_timer(), > so that clocks are initialized before clocksource for non device-tree. > For device-tree, the standard arm time_init() will take care of the > ordering. > > Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Reviewed-by: Michael Turquette <mturquette@linaro.org> > --- > arch/arm/mach-pxa/generic.c | 4 ++++ > arch/arm/mach-pxa/generic.h | 2 ++ > drivers/clk/pxa/clk-pxa27x.c | 3 +-- > 3 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/arch/arm/mach-pxa/generic.c b/arch/arm/mach-pxa/generic.c > index 04b013f..d988c53 100644 > --- a/arch/arm/mach-pxa/generic.c > +++ b/arch/arm/mach-pxa/generic.c > @@ -63,6 +63,10 @@ EXPORT_SYMBOL(get_clock_tick_rate); > */ > void __init pxa_timer_init(void) > { > + if (cpu_is_pxa25x()) > + pxa25x_clocks_init(); > + if (cpu_is_pxa27x()) > + pxa27x_clocks_init(); > pxa_timer_nodt_init(IRQ_OST0, io_p2v(0x40a00000), > get_clock_tick_rate()); > } > diff --git a/arch/arm/mach-pxa/generic.h b/arch/arm/mach-pxa/generic.h > index 7a9fa1a..149087c 100644 > --- a/arch/arm/mach-pxa/generic.h > +++ b/arch/arm/mach-pxa/generic.h > @@ -26,11 +26,13 @@ extern void pxa_timer_init(void); > #define ARRAY_AND_SIZE(x) (x), ARRAY_SIZE(x) > > #define pxa25x_handle_irq icip_handle_irq > +extern int __init pxa25x_clocks_init(void); > extern void __init pxa25x_init_irq(void); > extern void __init pxa25x_map_io(void); > extern void __init pxa26x_init_irq(void); > > #define pxa27x_handle_irq ichp_handle_irq > +extern int __init pxa27x_clocks_init(void); > extern void __init pxa27x_dt_init_irq(void); > extern unsigned pxa27x_get_clk_frequency_khz(int); > extern void __init pxa27x_init_irq(void); > diff --git a/drivers/clk/pxa/clk-pxa27x.c b/drivers/clk/pxa/clk-pxa27x.c > index 5f9b54b..2b8343a 100644 > --- a/drivers/clk/pxa/clk-pxa27x.c > +++ b/drivers/clk/pxa/clk-pxa27x.c > @@ -362,12 +362,11 @@ static void __init pxa27x_base_clocks_init(void) > clk_register_clk_pxa27x_lcd_base(); > } > > -static int __init pxa27x_clocks_init(void) > +int __init pxa27x_clocks_init(void) > { > pxa27x_base_clocks_init(); > return clk_pxa_cken_init(pxa27x_clocks, ARRAY_SIZE(pxa27x_clocks)); > } > -postcore_initcall(pxa27x_clocks_init); > > static void __init pxa27x_dt_clocks_init(struct device_node *np) > { > -- > 2.1.0 >
diff --git a/arch/arm/mach-pxa/generic.c b/arch/arm/mach-pxa/generic.c index 04b013f..d988c53 100644 --- a/arch/arm/mach-pxa/generic.c +++ b/arch/arm/mach-pxa/generic.c @@ -63,6 +63,10 @@ EXPORT_SYMBOL(get_clock_tick_rate); */ void __init pxa_timer_init(void) { + if (cpu_is_pxa25x()) + pxa25x_clocks_init(); + if (cpu_is_pxa27x()) + pxa27x_clocks_init(); pxa_timer_nodt_init(IRQ_OST0, io_p2v(0x40a00000), get_clock_tick_rate()); } diff --git a/arch/arm/mach-pxa/generic.h b/arch/arm/mach-pxa/generic.h index 7a9fa1a..149087c 100644 --- a/arch/arm/mach-pxa/generic.h +++ b/arch/arm/mach-pxa/generic.h @@ -26,11 +26,13 @@ extern void pxa_timer_init(void); #define ARRAY_AND_SIZE(x) (x), ARRAY_SIZE(x) #define pxa25x_handle_irq icip_handle_irq +extern int __init pxa25x_clocks_init(void); extern void __init pxa25x_init_irq(void); extern void __init pxa25x_map_io(void); extern void __init pxa26x_init_irq(void); #define pxa27x_handle_irq ichp_handle_irq +extern int __init pxa27x_clocks_init(void); extern void __init pxa27x_dt_init_irq(void); extern unsigned pxa27x_get_clk_frequency_khz(int); extern void __init pxa27x_init_irq(void); diff --git a/drivers/clk/pxa/clk-pxa27x.c b/drivers/clk/pxa/clk-pxa27x.c index 5f9b54b..2b8343a 100644 --- a/drivers/clk/pxa/clk-pxa27x.c +++ b/drivers/clk/pxa/clk-pxa27x.c @@ -362,12 +362,11 @@ static void __init pxa27x_base_clocks_init(void) clk_register_clk_pxa27x_lcd_base(); } -static int __init pxa27x_clocks_init(void) +int __init pxa27x_clocks_init(void) { pxa27x_base_clocks_init(); return clk_pxa_cken_init(pxa27x_clocks, ARRAY_SIZE(pxa27x_clocks)); } -postcore_initcall(pxa27x_clocks_init); static void __init pxa27x_dt_clocks_init(struct device_node *np) {
Since pxa clocks were ported to the clock framework, an ordering issue appears between clocks and clocksource initialization. As a consequence, the pxa timer clock cannot be acquired in pxa_timer, and is disabled by clock framework because it is "unused". The ordering issue is that in the kernel boot sequence : start_kernel() ... time_init() -> pxa_timer() -> here the clocksource is initialized ... rest_init() kernel_init() initcalls -> here the clocks are initialized In the current sequence, the clocks are initialized way after pxa_timer, which cannot acquire the OSTIMER0 clock. To solve this issue, the clocks initialization is moved to pxa_timer(), so that clocks are initialized before clocksource for non device-tree. For device-tree, the standard arm time_init() will take care of the ordering. Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> --- arch/arm/mach-pxa/generic.c | 4 ++++ arch/arm/mach-pxa/generic.h | 2 ++ drivers/clk/pxa/clk-pxa27x.c | 3 +-- 3 files changed, 7 insertions(+), 2 deletions(-)