On Fri, Dec 13, 2013 at 5:04 AM, Benoît Thébaudeau <[email protected]> wrote: > On Friday, December 13, 2013 1:52:19 AM, Benoît Thébaudeau wrote: >> Dear Sergey Alyoshin, >> >> On Thursday, December 12, 2013 5:46:21 PM, Sergey Alyoshin wrote: >> > Enable fuse supply gate before fuse programming and disable after. >> > >> > Signed-off-by: Sergey Alyoshin <[email protected]> >> > Tested-by: Sergey Alyoshin <[email protected]> >> >> Have you also tested without this patch first too? On which SoC? >> >> My tests had shown that this is not required on i.MX51. It's probably the >> same >> on i.MX53. I have not checked if i.MX25 and i.MX35 also have such a bit, but >> they also work fine as is. This is not even done by Freescale: >> http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/drivers/char/mxc_iim.c?h=imx_3.0.35_4.1.0 >> >> In the Reference Manual, nothing says in the IIM / fuse chapters that this >> bit >> is needed for proper programming. It is just described in the CCM register >> map, >> and nothing refers to it. It is perhaps only useful for test purposes. I'd >> vote >> for letting this bit untouched if possible. >> >> Fabio, do you have more information from Freescale about this bit? > > Also note that the data sheets of the i.MX51 and i.MX53 both mention a > dedicated > VDD_FUSE pin, with several notes saying that it should not be powered if > programming is not required in order to avoid inadvertently blowing fuses in > read mode. These notes would not be required if this bit gating this supply by > default really did exactly that. I think that it is rather an internal feature > for Freescale only, e.g. to blow Freescale bits like UID in die production.
I apply 3.3V on VDD_FUSE pin and still without setting EFUSE_PROG_SUPPLY_GATE bank 1 was not programmed on i.MX53. _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
