Re: [LinuxBIOS] Fwd: Re: smbus_write_byte

[Corey Osgood]

Joseph Smith wrote:
> Quoting Marc Jones :
> > Joseph Smith wrote:
> > > Quoting Corey Osgood :
> > > > yhlu wrote:
> > > > > just provide one fake spd array...
> > > > >
> > > > > YH
> > > >
> > > > My thoughts exactly. You can't write to the smbus because there's no
> > > > device on the smbus at that location to receive those writes.
> > > >
> > > > -Corey
> > >
> > > How would I provide a fake spd array? Here is the situation. My  
> > > board  has the onboard memory without a SPD, I could just hardcode 
> > >  this into  the northbridge raminit.c. But I don't want to do that 
> > >  so people that  may want to use the northbridge src for other  
> > > boards won't have to  deal with it. So right now I have auto.c call
> > >   a function that runs in  between sdram_set_spd_registers and  
> > > sdram_enable, like this:
> > > sdram_set_spd_registers(memctrl);
> > > onboard_sdram_set_registers(memctrl);
> > > sdram_enable(0, memctrl);
> > >
> > > This function, onboard_sdram_set_registers manually sets up the
> > > regsters.
> > >
> > > Anyways I would also like to get the smbus_write_byte write going  
> > > to  setup my tv-out registers on my tv-out chip?
> > >
> > > Thanks - Joe
> >
> > Joe,
> > There is an example of an spd array in
> > mainboard/artecgroup/dbe61/cache_as_ram_auto.c spd_read_byte(). You
> > will have to generate the correct SPD values for your memory.
> >
> > Is the normal smbus_write_byte not working?
> >
> > Marc
>
> Thanks everyone for your help. No, the smbus_write_byte is commented
> out and has a big FIXME. I assume the code just never got finished??

Hmm, smbus_write_byte is commented in the original code
(intel/i82801db/i82801db_early_smbus.c), but smbus_write_block is not,
so it should work with the comments removed. Does that help at all?

-Corey
> static void smbus_write_byte(unsigned device, unsigned address,
> unsigned char val)
> {
>     if (smbus_wait_until_ready(SMBUS_IO_BASE) < 0) {
>         return;
>     }
> print_debug("Unimplemented smbus_write_byte() called.\r\n");
>
> #if 0
>     /* setup transaction */
>     /* disable interrupts */
>     outw(inw(SMBUS_IO_BASE + SMBGCTL) & ~((1<<10)|(1<<9)|(1<<8)|(1<<4)),
>             SMBUS_IO_BASE + SMBGCTL);
>     /* set the device I'm talking too */
>     outw(((device & 0x7f) << 1) | 1, SMBUS_IO_BASE + SMBHSTADDR);
>     outb(address & 0xFF, SMBUS_IO_BASE + SMBHSTCMD);
>     /* set up for a byte data write */ /* FIXME */
>     outw((inw(SMBUS_IO_BASE + SMBGCTL) & ~7) | (0x1), SMBUS_IO_BASE +
> SMBGCTL);
>     /* clear any lingering errors, so the transaction will run */
>     /* Do I need to write the bits to a 1 to clear an error? */
>     outw(inw(SMBUS_IO_BASE + SMBGSTATUS), SMBUS_IO_BASE + SMBGSTATUS);
> /* clear the data word...*/
> outw(val, SMBUS_IO_BASE + SMBHSTDAT);
>
> /* start the command */
> outw((inw(SMBUS_IO_BASE + SMBGCTL) | (1 << 3)), SMBUS_IO_BASE +
>
> SMBGCTL);
> /* poll for transaction completion */
> smbus_wait_until_done(SMBUS_IO_BASE);
>
> #endif
>     return;
> }
>
> Thanks - Joe