[PATCH 1/3] at91: add boot mode detection support

Jean-Christophe PLAGNIOL-VILLARD plagnioj at jcrosoft.com
Wed Feb 6 13:45:18 EST 2013


On 19:27 Wed 06 Feb     , Sascha Hauer wrote:
> +1 for getting something common. On i.MX we currently use the
> barebox_loc environment variable. Not that I you should do the same for
> Atmel, but we should come up with something both i.MX and Atmel can be
> converted to.
> 
> > +
> > +	dev = add_generic_device_res("bootloc", DEVICE_ID_SINGLE, NULL, 0, NULL);
> 
> I know you are concerned about performance when the single 'global'
> device has many variables. I think the performance can be greatly
> improved by making sure the global device is the first one to be
> registered.
> 
> IMO adding a new device for every fart in the system does not improve the
> situation.
because this is RO data and I do not like global for specific stuff

global need to be for shell var create

and via specific dev with devinfo you can see to params quick and clear
> 
> > +enum at91_soc_boot_from {
> > +	AT91_BOOT_FROM_UNKNOWN,
> > +	AT91_BOOT_FROM_SPI,
> > +	AT91_BOOT_FROM_MCI,
> > +	AT91_BOOT_FROM_SMC,
> > +	AT91_BOOT_FROM_TWD,
> > +};
> > +
> > +enum at91_soc_boot_media {
> > +	AT91_BOOT_MEDIA_UNKNOWN,
> > +	AT91_BOOT_MEDIA_SD,
> > +	AT91_BOOT_MEDIA_MMC,
> > +	AT91_BOOT_MEDIA_EMMC,
> > +	AT91_BOOT_MEDIA_AT45,
> > +	AT91_BOOT_MEDIA_AT25,
> > +	AT91_BOOT_MEDIA_NAND,
> > +	AT91_BOOT_MEDIA_NOR,
> > +};
> 
> Hm. For NAND/NOR the first array does not contain useful information,
> for MCI the second array does not contain useful information. For
> I2C/SPI both arrays seem redundant.
> 
> Why not merge them into one?

no because SMC is for NAND & NOR
SPI => at25/at45
MCI => SD/MMC/eMMC

we have the different information in the register I want to expose it

use full for IC debug as example and boot strategie

Best Regards,
J.
> 
> Sascha
> 
> -- 
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