IDE probing IDE_MAX_HWIFS

IDE probing IDE_MAX_HWIFS

[Nick Warne]

Hello everybody,

I am investigating the IDE probing at boot (i386), and wanted to find an easy 
way to pass the 'noprobe' command line to all the (non-existant) IDE 
interfaces at once(ish) rather than having 'ide2=noprobe ide3=noprobe 
ide4=noprobe...'

Now I have traced the code, I see that HWIFS is 6 or 10
include/asm-i386/ide.h:

#ifndef MAX_HWIFS
# ifdef CONFIG_BLK_DEV_IDEPCI
#define MAX_HWIFS       10
# else
#define MAX_HWIFS       6
# endif
#endif

Looking at the Kconfig, I see APLHA & SUPERH do get an option to change this 
to suit
drivers/ide/Kconfig

config IDE_MAX_HWIFS
        int "Max IDE interfaces"
        depends on ALPHA || SUPERH
        default 4
        help
          This is the maximum number of IDE hardware interfaces that will
          be supported by the driver. Make sure it is at least as high as
          the number of IDE interfaces in your system.

Now my question :-)  Is there a specific reason why this isn't included in 
other architectures?  I am asking as I guess one hell of a lot of people 
running on i386 have only two IDE interfaces anyway, and it could do with 
defining it as 2...

Thanks,

Nick
-- 
"When you're chewing on life's gristle,
Don't grumble, Give a whistle..."

Re: IDE probing IDE_MAX_HWIFS

[Alan Cox]

On Sad, 2005-06-25 at 12:10, Nick Warne wrote:
> Looking at the Kconfig, I see APLHA & SUPERH do get an option to change this 
> to suit
> drivers/ide/Kconfig

To make embedded systems as small as possible

> Now my question :-)  Is there a specific reason why this isn't included in 
> other architectures?

They are not embedded ?

Re: IDE probing IDE_MAX_HWIFS

[Nick Warne]

On Sunday 26 June 2005 18:51, you wrote:
> On Sad, 2005-06-25 at 12:10, Nick Warne wrote:
> > Looking at the Kconfig, I see APLHA & SUPERH do get an option to change
> > this to suit
> > drivers/ide/Kconfig
>
> To make embedded systems as small as possible
>
> > Now my question :-)  Is there a specific reason why this isn't included
> > in other architectures?
>
> They are not embedded ?

Heh.  Yes I know now, but I was thinking along the lines that if someone knows 
how many IDE interfaces they have it could be specified exactly - I 
didn't/don't see why it is considered an option for config_embedded only to 
be allowed to do that.

Nick
-- 
"When you're chewing on life's gristle,
Don't grumble, Give a whistle..."

Re: IDE probing IDE_MAX_HWIFS

[Alan Cox]

On Sul, 2005-06-26 at 19:08, Nick Warne wrote:
> Heh.  Yes I know now, but I was thinking along the lines that if someone knows 
> how many IDE interfaces they have it could be specified exactly - I 
> didn't/don't see why it is considered an option for config_embedded only to 
> be allowed to do that.

Its a trade off. If you allow every configuration option kernel
configuration begins to resemble an inquisition.

Re: IDE probing IDE_MAX_HWIFS

[Nick Warne]

> Now my question :-)  Is there a specific reason why this isn't included in
> other architectures?  I am asking as I guess one hell of a lot of people
> running on i386 have only two IDE interfaces anyway, and it could do with
> defining it as 2...

I have a patch here, works very well.  But I need to see if I am a bit 'Mickey 
Mouse' and need to ask all you proper coders if this would be an acceptable 
patch.

In drivers/ide/Kconfig

if IDE

config IDE_HWIFS_NUM
        bool "Specify the number of IDE Interfaces"
        depends on (ALPHA || SUPERH || X86)
        default n
        help

          ALPHA and SUPERH say 'y' here.

          X86 say 'y' to this if you wish to specify the number of IDE
          interfaces on your system.  If unsure, say 'n' to use
          the kernel default options (6 or 10).

config IDE_MAX_HWIFS
        int "Max IDE interfaces"
        depends on IDE_HWIFS_NUM
        default 4
        help
          This is the maximum number of IDE hardware interfaces that will
          be supported by the driver. Make sure it is at least as high as
          the number of IDE interfaces in your system.

          On X86 architecture default is (10 or 6) IDE interfaces if this
          is not used (IDE_HWIFS_NUM = n)



and in include/asm-i386/ide.h

#ifndef MAX_HWIFS
#ifndef CONFIG_IDE_HWIFS_NUM
# ifdef CONFIG_BLK_DEV_IDEPCI
#define MAX_HWIFS       10
# else
#define MAX_HWIFS       6
# endif
#else
#define MAX_HWIFS       CONFIG_IDE_MAX_HWIFS
#endif
#endif


I have just built and it works great - boot time seems to increase a lot (but 
I haven't measured as such).  It also eliminates me needing all the 
idex=noprobe also.

Nick
-- 
"When you're chewing on life's gristle,
Don't grumble, Give a whistle..."