Re: [PATCH v3 1/7] of/serial: move earlycon early_param handling to serial

[Peter Hurley <peter@hurleysoftware.com>]

On 03/01/2016 08:31 AM, Aleksey Makarov wrote:
> 
> 
> On 03/01/2016 05:50 PM, Peter Hurley wrote:
>> On 02/29/2016 04:41 AM, Aleksey Makarov wrote:
>>> From: Leif Lindholm <leif.lindholm@linaro.org>
>>>
>>> We have multiple "earlycon" early_param handlers - merge the DT one into
>>> the main earlycon one. This means the earlycon early_param handler does
>>> not just return success if no options are specified.
>>
>> Why is this patch necessary?
>>
>> Is this cleanup or required for some reason in other parts of this
>> series?
> 
> It's a cleanup.
> 
> Also, without this, the series has to introduce a new (third) handler for "earlycon=".

Not if it were opt-in like OF is via the same blank
"earlycon" parameter.


>>> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
>>> Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
>>> ---
>>>  drivers/of/fdt.c              | 11 +----------
>>>  drivers/tty/serial/earlycon.c |  3 ++-
>>>  include/linux/of_fdt.h        |  2 ++
>>>  3 files changed, 5 insertions(+), 11 deletions(-)
>>>
>>> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
>>> index 3349d2a..0547256 100644
>>> --- a/drivers/of/fdt.c
>>> +++ b/drivers/of/fdt.c
>>> @@ -805,7 +805,7 @@ static inline void early_init_dt_check_for_initrd(unsigned long node)
>>>  
>>>  #ifdef CONFIG_SERIAL_EARLYCON
>>>  
>>> -static int __init early_init_dt_scan_chosen_serial(void)
>>> +int __init early_init_dt_scan_chosen_serial(void)
>>>  {
>>>  	int offset;
>>>  	const char *p, *q, *options = NULL;
>>> @@ -849,15 +849,6 @@ static int __init early_init_dt_scan_chosen_serial(void)
>>>  	}
>>>  	return -ENODEV;
>>>  }
>>> -
>>> -static int __init setup_of_earlycon(char *buf)
>>> -{
>>> -	if (buf)
>>> -		return 0;
>>> -
>>> -	return early_init_dt_scan_chosen_serial();
>>> -}
>>> -early_param("earlycon", setup_of_earlycon);
>>>  #endif
>>>  
>>>  /**
>>> diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
>>> index 067783f..d217366 100644
>>> --- a/drivers/tty/serial/earlycon.c
>>> +++ b/drivers/tty/serial/earlycon.c
>>> @@ -17,6 +17,7 @@
>>>  #include <linux/kernel.h>
>>>  #include <linux/init.h>
>>>  #include <linux/io.h>
>>> +#include <linux/of_fdt.h>
>>>  #include <linux/serial_core.h>
>>>  #include <linux/sizes.h>
>>>  #include <linux/of.h>
>>> @@ -209,7 +210,7 @@ static int __init param_setup_earlycon(char *buf)
>>>  	 * don't generate a warning from parse_early_params() in that case
>>>  	 */
>>>  	if (!buf || !buf[0])
>>> -		return 0;
>>> +		return early_init_dt_scan_chosen_serial();
>>>  
>>>  	err = setup_earlycon(buf);
>>>  	if (err == -ENOENT || err == -EALREADY)
>>> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
>>> index 2fbe868..56b2a43 100644
>>> --- a/include/linux/of_fdt.h
>>> +++ b/include/linux/of_fdt.h
>>> @@ -63,6 +63,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
>>>  				     int depth, void *data);
>>>  extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
>>>  				     int depth, void *data);
>>> +extern int early_init_dt_scan_chosen_serial(void);
>>>  extern void early_init_fdt_scan_reserved_mem(void);
>>>  extern void early_init_fdt_reserve_self(void);
>>>  extern void early_init_dt_add_memory_arch(u64 base, u64 size);
>>> @@ -91,6 +92,7 @@ extern void early_get_first_memblock_info(void *, phys_addr_t *);
>>>  extern u64 of_flat_dt_translate_address(unsigned long node);
>>>  extern void of_fdt_limit_memory(int limit);
>>>  #else /* CONFIG_OF_FLATTREE */
>>> +static inline int early_init_dt_scan_chosen_serial(void) { return -ENODEV; }
>>>  static inline void early_init_fdt_scan_reserved_mem(void) {}
>>>  static inline void early_init_fdt_reserve_self(void) {}
>>>  static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }
>>>
>>