Re: [LinuxBIOS] patch 2:corrected alix1c memory size

[Uwe Hermann]

On Thu, Oct 25, 2007 at 08:55:10PM -0700, ron minnich wrote:
> p.s. will send memory image and instructions to anyone who wants to take a try.

Please rather make a wiki page out of the instructions, i.e.

http://linuxbios.org/index.php?title=PC_Engines_ALIX.1C_Build_Tutorial&a...

(and attach a license template, please, e.g. {{GPL}} or {{PD-self}} etc).

Later a full status table as we have for some other boards now would be
great.
> +static u8 spd_read_byte(unsigned device, unsigned address)

Maybe

static u8 spd_read_byte(u16 device, u16 address)

Are device and address of fixed size (16 bit)? Or rather 8 bit?
> {
> return smbus_read_byte(device, address);
> print_debug("spd_read_byte dev ");
> print_debug_hex8(device);

You use *hex8 here, but device is 16 bit above. One of them should
be fixed.
> if (device != (0x50<<1)){
> print_debug(" returns 0xff\n");
> return 0xff;
> }
> print_debug(" addr ");
> print_debug_hex8(address);

Ditto.
> /* Switch from Cache as RAM to real RAM */
> /* There are two ways we could think about this.
> 1. If we are using the auto.inc ROMCC way, the stack is going to be re-setup in the code following this code.
> Just wbinvd the stack to clear the cache tags. We don't care where the stack used to be.
> 2. This file is built as a normal .c -> .o and linked in etc. The stack might be used to return etc.
> That means we care about what is in the stack. If we are smart we set the CAR stack to the same location
> as the rest of LinuxBIOS. If that is the case we can just do a wbinvd. The stack will be written into real
> RAM that is now setup and we continue like nothing happened. If the stack is located somewhere other than
> where LB would like it, you need to write some code to do a copy from cache to RAM
> We use method 1 on Norwich and on this board too. 
> */
> /* Switch from Cache as RAM to real RAM
> * There are two ways we could think about this.  
> *
> * 1. If we are using the auto.inc ROMCC way, the stack is
> * going to be re-setup in the code following this code.  Just
> * wbinvd the stack to clear the cache tags.  We don't care
> * where the stack used to be.
> * 
> * 2. This file is built as a normal .c -> .o and linked in
> * etc.  The stack might be used to return etc.  That means we
> * care about what is in the stack.  If we are smart we set
> * the CAR stack to the same location as the rest of
> * LinuxBIOS. If that is the case we can just do a wbinvd.
> * The stack will be written into real RAM that is now setup
> * and we continue like nothing happened.  If the stack is
> * located somewhere other than where LB would like it, you
> * need to write some code to do a copy from cache to RAM
> *
> * We use method 1 on Norwich and on this board too. 
> */

Yep, much better.

Uwe.