2003-05-20 00:44:18

by J.C. Wren

[permalink] [raw]
Subject: Machin dependent serial port patches

One of the things I noticed in the port of 2.5.69 to the 386EX embedded
system is that serial.h appears to not be a mach-xxx positionable file. The
386EX board uses standard 8250 type serial ports, but at 3.6864Mhz instad of
1.8432Mhz. There appears to be no way to build a patch set without modifying
include/i386/serial.h. Would this not be better places in mach-defaults?
I'm trying very hard to modify as few files as possible when building these
patch sets.

--John


2003-05-20 12:54:34

by Alan

[permalink] [raw]
Subject: Re: Machin dependent serial port patches

On Maw, 2003-05-20 at 01:56, J.C. Wren wrote:
> One of the things I noticed in the port of 2.5.69 to the 386EX embedded
> system is that serial.h appears to not be a mach-xxx positionable file. The
> 386EX board uses standard 8250 type serial ports, but at 3.6864Mhz instad of
> 1.8432Mhz. There appears to be no way to build a patch set without modifying
> include/i386/serial.h. Would this not be better places in mach-defaults?
> I'm trying very hard to modify as few files as possible when building these
> patch sets.

Making asm-i386/serial.h include a mach- file sounds the right thing to
do. mach- for x86 is pretty new so a lot of stuff that maybe should be
in it, hasnt migrated yet.

The counter argument however is that you should be able to use setserial
to adjust the baud base so you dont need to change anything 8)

2003-05-20 13:45:24

by J.C. Wren

[permalink] [raw]
Subject: Re: Machin dependent serial port patches

The only prolem with using setserial is my console is one one of these serial
port (headless system. I failed to mention that earlier). So everything
that comes out the console at the wrong rate :( However, Milton D. Miller
suggested looking at early_serial_rgister, which is used on ppc and ia64.
That might help.

--John

On Tuesday 20 May 2003 08:09 am, Alan Cox wrote:
> On Maw, 2003-05-20 at 01:56, J.C. Wren wrote:
> > One of the things I noticed in the port of 2.5.69 to the 386EX embedded
> > system is that serial.h appears to not be a mach-xxx positionable file.
> > The 386EX board uses standard 8250 type serial ports, but at 3.6864Mhz
> > instad of 1.8432Mhz. There appears to be no way to build a patch set
> > without modifying include/i386/serial.h. Would this not be better places
> > in mach-defaults? I'm trying very hard to modify as few files as possible
> > when building these patch sets.
>
> Making asm-i386/serial.h include a mach- file sounds the right thing to
> do. mach- for x86 is pretty new so a lot of stuff that maybe should be
> in it, hasnt migrated yet.
>
> The counter argument however is that you should be able to use setserial
> to adjust the baud base so you dont need to change anything 8)
>
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2003-05-28 09:31:03

by David Woodhouse

[permalink] [raw]
Subject: Re: Machin dependent serial port patches

On Tue, 2003-05-20 at 13:09, Alan Cox wrote:
> On Maw, 2003-05-20 at 01:56, J.C. Wren wrote:
> > One of the things I noticed in the port of 2.5.69 to the 386EX embedded
> > system is that serial.h appears to not be a mach-xxx positionable file. The
> > 386EX board uses standard 8250 type serial ports, but at 3.6864Mhz instad of
> > 1.8432Mhz. There appears to be no way to build a patch set without modifying
> > include/i386/serial.h. Would this not be better places in mach-defaults?
> > I'm trying very hard to modify as few files as possible when building these
> > patch sets.
>
> Making asm-i386/serial.h include a mach- file sounds the right thing to
> do. mach- for x86 is pretty new so a lot of stuff that maybe should be
> in it, hasnt migrated yet.

I disagree. I think it would be better to get rid of the hard-coded
table altogether and let something in the machine-specific code call
register_serial() during early boot.

Even on PeeCee hardware, that lets us do the superio chip probe and
potentially register high-speed serial ports, before the pnpbios probe
and finally falling back to the old standard I/O addresses.

--
dwmw2