[v1] clk: Export __clk_lookup()
diff mbox series

Message ID 20200722023230.10826-1-zhangqing@rock-chips.com
State New
Headers show
Series
  • [v1] clk: Export __clk_lookup()
Related show

Commit Message

elaine.zhang July 22, 2020, 2:32 a.m. UTC
Export __clk_lookup() to support user built as module.

ERROR:
drivers/clk/rockchip/clk.ko: In function
`rockchip_clk_protect_critical':
drivers/clk/rockchip/clk.c:741:
undefined reference to `__clk_lookup'

Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
---
 drivers/clk/clk.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Heiko Stübner July 22, 2020, 6:26 p.m. UTC | #1
Hi Elaine,

Am Mittwoch, 22. Juli 2020, 04:32:30 CEST schrieb Elaine Zhang:
> Export __clk_lookup() to support user built as module.
> 
> ERROR:
> drivers/clk/rockchip/clk.ko: In function
> `rockchip_clk_protect_critical':
> drivers/clk/rockchip/clk.c:741:
> undefined reference to `__clk_lookup'

can you elaborate a bit more on why this would be needed?

Because right now the Rockchip clocks are of course built into
the main kernel image (especially due to them being needed during early
boot) and __clk_lookup actually is a pretty deep part of the clock-
framework itself, as probably also denoted by the "__" in the function
name.


Heiko

> Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
> ---
>  drivers/clk/clk.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index 3f588ed06ce3..600284fbb257 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -618,6 +618,7 @@ struct clk *__clk_lookup(const char *name)
>  
>  	return !core ? NULL : core->hw->clk;
>  }
> +EXPORT_SYMBOL_GPL(__clk_lookup);
>  
>  static void clk_core_get_boundaries(struct clk_core *core,
>  				    unsigned long *min_rate,
>
Stephen Boyd July 23, 2020, 12:51 a.m. UTC | #2
Quoting Heiko Stuebner (2020-07-22 11:26:50)
> Hi Elaine,
> 
> Am Mittwoch, 22. Juli 2020, 04:32:30 CEST schrieb Elaine Zhang:
> > Export __clk_lookup() to support user built as module.
> > 
> > ERROR:
> > drivers/clk/rockchip/clk.ko: In function
> > `rockchip_clk_protect_critical':
> > drivers/clk/rockchip/clk.c:741:
> > undefined reference to `__clk_lookup'
> 
> can you elaborate a bit more on why this would be needed?
> 
> Because right now the Rockchip clocks are of course built into
> the main kernel image (especially due to them being needed during early
> boot) and __clk_lookup actually is a pretty deep part of the clock-
> framework itself, as probably also denoted by the "__" in the function
> name.
> 

Can you stop using __clk_lookup()? The plan is to remove it.
elaine.zhang July 23, 2020, 1:42 a.m. UTC | #3
在 2020/7/23 上午8:51, Stephen Boyd 写道:
> Quoting Heiko Stuebner (2020-07-22 11:26:50)
>> Hi Elaine,
>>
>> Am Mittwoch, 22. Juli 2020, 04:32:30 CEST schrieb Elaine Zhang:
>>> Export __clk_lookup() to support user built as module.
>>>
>>> ERROR:
>>> drivers/clk/rockchip/clk.ko: In function
>>> `rockchip_clk_protect_critical':
>>> drivers/clk/rockchip/clk.c:741:
>>> undefined reference to `__clk_lookup'
>> can you elaborate a bit more on why this would be needed?
>>
>> Because right now the Rockchip clocks are of course built into
>> the main kernel image (especially due to them being needed during early
>> boot) and __clk_lookup actually is a pretty deep part of the clock-
>> framework itself, as probably also denoted by the "__" in the function
>> name.
>>
> Can you stop using __clk_lookup()? The plan is to remove it.

Rk use  __clk_lookup() as:

drivers/clk/rockchip/clk.c

void __init rockchip_clk_protect_critical(const char *const clocks[],
                                           int nclocks)
{
         int i;

         /* Protect the clocks that needs to stay on */
         for (i = 0; i < nclocks; i++) {
                 struct clk *clk = __clk_lookup(clocks[i]);

                 if (clk)
                         clk_prepare_enable(clk);
         }
}
e.g:

drivers/clk/rockchip/clk-rk3328.c

static const char *const rk3328_critical_clocks[] __initconst = {
         "aclk_bus",
         "aclk_bus_niu",
         "pclk_bus",
         "pclk_bus_niu",
         "hclk_bus",
         "hclk_bus_niu",
         "aclk_peri",
............

};

If have plan to remove the __clk_lookup, I need to replace the 
rockchip_clk_protect_critical, and use the flag CLK_IS_CRITICAL.(but use 
flag CLK_IS_CRITICAL, the enable count is always "0")

>
>
elaine.zhang July 23, 2020, 1:49 a.m. UTC | #4
在 2020/7/23 上午9:42, elaine.zhang 写道:
>
> 在 2020/7/23 上午8:51, Stephen Boyd 写道:
>> Quoting Heiko Stuebner (2020-07-22 11:26:50)
>>> Hi Elaine,
>>>
>>> Am Mittwoch, 22. Juli 2020, 04:32:30 CEST schrieb Elaine Zhang:
>>>> Export __clk_lookup() to support user built as module.
>>>>
>>>> ERROR:
>>>> drivers/clk/rockchip/clk.ko: In function
>>>> `rockchip_clk_protect_critical':
>>>> drivers/clk/rockchip/clk.c:741:
>>>> undefined reference to `__clk_lookup'
>>> can you elaborate a bit more on why this would be needed?
>>>
>>> Because right now the Rockchip clocks are of course built into
>>> the main kernel image (especially due to them being needed during early
>>> boot) and __clk_lookup actually is a pretty deep part of the clock-
>>> framework itself, as probably also denoted by the "__" in the function
>>> name.
>>>
>> Can you stop using __clk_lookup()? The plan is to remove it.
>
> Rk use  __clk_lookup() as:
>
> drivers/clk/rockchip/clk.c
>
> void __init rockchip_clk_protect_critical(const char *const clocks[],
>                                           int nclocks)
> {
>         int i;
>
>         /* Protect the clocks that needs to stay on */
>         for (i = 0; i < nclocks; i++) {
>                 struct clk *clk = __clk_lookup(clocks[i]);
>
>                 if (clk)
>                         clk_prepare_enable(clk);
>         }
> }
> e.g:
>
> drivers/clk/rockchip/clk-rk3328.c
>
> static const char *const rk3328_critical_clocks[] __initconst = {
>         "aclk_bus",
>         "aclk_bus_niu",
>         "pclk_bus",
>         "pclk_bus_niu",
>         "hclk_bus",
>         "hclk_bus_niu",
>         "aclk_peri",
> ............
>
> };
>
> If have plan to remove the __clk_lookup, I need to replace the 
> rockchip_clk_protect_critical, and use the flag CLK_IS_CRITICAL.(but 
> use flag CLK_IS_CRITICAL, the enable count is always "0")
Use the CLK_IS_CRITICAL, there is no guarantee that the parent clk is 
enabled, So the flag CLK_IS_CRITICAL need to be added to all special 
clks according to the clk tree.
>
>>
>>
elaine.zhang July 23, 2020, 3:36 a.m. UTC | #5
在 2020/7/23 上午2:26, Heiko Stuebner 写道:
> Hi Elaine,
>
> Am Mittwoch, 22. Juli 2020, 04:32:30 CEST schrieb Elaine Zhang:
>> Export __clk_lookup() to support user built as module.
>>
>> ERROR:
>> drivers/clk/rockchip/clk.ko: In function
>> `rockchip_clk_protect_critical':
>> drivers/clk/rockchip/clk.c:741:
>> undefined reference to `__clk_lookup'
> can you elaborate a bit more on why this would be needed?
>
> Because right now the Rockchip clocks are of course built into
> the main kernel image (especially due to them being needed during early
> boot) and __clk_lookup actually is a pretty deep part of the clock-
> framework itself, as probably also denoted by the "__" in the function
> name.

Rockchip clocks are of course support to built as module(to support GKI),These changes will be pushed soon.
In drivers/clk/rockchip/clk.c and drivers/clk/rockchip/clk-cpu.c use the __clk_lookup.

>
>
> Heiko
>
>> Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
>> ---
>>   drivers/clk/clk.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
>> index 3f588ed06ce3..600284fbb257 100644
>> --- a/drivers/clk/clk.c
>> +++ b/drivers/clk/clk.c
>> @@ -618,6 +618,7 @@ struct clk *__clk_lookup(const char *name)
>>   
>>   	return !core ? NULL : core->hw->clk;
>>   }
>> +EXPORT_SYMBOL_GPL(__clk_lookup);
>>   
>>   static void clk_core_get_boundaries(struct clk_core *core,
>>   				    unsigned long *min_rate,
>>
>
>
>
>
>

Patch
diff mbox series

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 3f588ed06ce3..600284fbb257 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -618,6 +618,7 @@  struct clk *__clk_lookup(const char *name)
 
 	return !core ? NULL : core->hw->clk;
 }
+EXPORT_SYMBOL_GPL(__clk_lookup);
 
 static void clk_core_get_boundaries(struct clk_core *core,
 				    unsigned long *min_rate,