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ARM: pxa: change clocks init sequence

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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.

Reviewed-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
This commit is contained in:
Robert Jarzmik 2014-12-27 14:55:25 +01:00
parent b787f68c36
commit 5e1d012851
3 changed files with 7 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/arm/mach-pxa/generic.c
View File

@ -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());
}

2
arch/arm/mach-pxa/generic.h
View File

@ -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);

3
drivers/clk/pxa/clk-pxa27x.c
View File

@ -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)
{