[PATCH v1 4/5] DON'T MERGE ME: arm: pxa: change clocks init sequence
Robert Jarzmik
robert.jarzmik at free.fr
Mon Oct 6 16:08:00 PDT 2014
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 at free.fr>
---
arch/arm/mach-pxa/generic.c | 2 ++
arch/arm/mach-pxa/generic.h | 1 +
drivers/clk/pxa/clk-pxa27x.c | 3 +--
3 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-pxa/generic.c b/arch/arm/mach-pxa/generic.c
index 04b013f..4ca801b 100644
--- a/arch/arm/mach-pxa/generic.c
+++ b/arch/arm/mach-pxa/generic.c
@@ -63,6 +63,8 @@ EXPORT_SYMBOL(get_clock_tick_rate);
*/
void __init pxa_timer_init(void)
{
+ 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 8963984..7fda082 100644
--- a/arch/arm/mach-pxa/generic.h
+++ b/arch/arm/mach-pxa/generic.h
@@ -14,6 +14,7 @@
struct irq_data;
extern void pxa_timer_init(void);
+extern int pxa27x_clocks_init(void);
extern void __init pxa_map_io(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
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