From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shyam Saini <shyam@amarulasolutions.com>
Date: Thu, 21 Mar 2019 15:21:37 +0530
Subject: [U-Boot] [PATCH] configs: icorem6: Use imx6 cratch register for
	bootcount
In-Reply-To: <a75767e1-b530-3111-8a3a-31115b0ccecb@denx.de>
References: <20190321083553.4068-1-jagan@amarulasolutions.com>
 <a75767e1-b530-3111-8a3a-31115b0ccecb@denx.de>
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To: u-boot@lists.denx.de

Hi Stefano,

Thanks a lot for reviewing this

> nitpick: cratch ==> scratch
>
> On 21/03/19 09:35, Jagan Teki wrote:
> > SRAM address used for bootcount on exiting code is erasing
> > previous count value when system reset from Linux. So use
> > the dedicated imx6 scratch register, GPR2 to preserve the
> > contents even if the system reset from Linux.
> >
> > Fixes: 4eb9aa39350e ("configs: imx6qdl_icore_mmc: Enable watchdog and bootcounter")
> > Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
> > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> > ---
> >  configs/imx6qdl_icore_mmc_defconfig | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/configs/imx6qdl_icore_mmc_defconfig b/configs/imx6qdl_icore_mmc_defconfig
> > index 68ad1c6d20..24e99718e6 100644
> > --- a/configs/imx6qdl_icore_mmc_defconfig
> > +++ b/configs/imx6qdl_icore_mmc_defconfig
> > @@ -16,7 +16,7 @@ CONFIG_CMD_BOOTCOUNT=y
> >  CONFIG_BOOTCOUNT_LIMIT=y
> >  CONFIG_BOOTCOUNT_BOOTLIMIT=3
> >  CONFIG_SYS_BOOTCOUNT_SINGLEWORD=y
> > -CONFIG_SYS_BOOTCOUNT_ADDR=0x00900000
> > +CONFIG_SYS_BOOTCOUNT_ADDR=0x020D8024
> >  CONFIG_SYS_BOOTCOUNT_MAGIC=0x0B01C041
> >  CONFIG_IMX_WATCHDOG=y
> >  CONFIG_DEBUG_UART=y
> >
>
> Just as info: I confirm that using start address of SRAM does not work.
> Rather even the GPRx registers are not a common solution. I have already
> seen that even the GPRx registers are touched and cannot be used on some
> i.MX6 variant. Anyway, if this works on your board, fine.

Since GPRx registers are common to i.MX6, I think it can work
irrespective of boards, please correct me
if I am missing something here.

Did you come across any generic and robust solution for this ?
It would be great if we can use more generic or better solution.
Please let us know.

Thanks a lot,
Shyam