[U-Boot] [PATCH 6/7] configs: tinker: Enable SDRAM, SPL stack

[Jagan Teki]

On Wed, Sep 18, 2019 at 3:24 PM Kever Yang <kever.yang at rock-chips.com> wrote:
>
>
> On 2019/9/18 下午1:25, Jagan Teki wrote:
> > On Wed, Sep 18, 2019 at 10:36 AM Kever Yang <kever.yang at rock-chips.com> wrote:
> >>
> >> On 2019/9/17 下午2:10, Jagan Teki wrote:
> >>> SPL sets up SDRAM while in its board_init_f()
> >>> function, it is possible for the stack to move
> >>> there before board_init_r() is reached.
> >>>
> >>> So it is required to reserve the stack for SDRAM,
> >>> with a proper location and size otherwise any
> >>> operations during SPL handoff would leads to failure.
> >>>
> >>> On, this particular context tinker-rk3288 SPL is
> >>> failing to launch U-Boot proper on SDRAM due to
> >>> lack of stack.
> >> If no SPL_STACK_R, it should still use CONFIG_SPL_STACK when system
> >> init, right?
> > SPL_STACK vs SPL_STTACK_R would be different in their usage former is
> > used to setup the stack during early while calling board_init_f but
> > the later used to setup the stack (with DRAM base) while calling
> > board_init_r. if CONFIG_SPL_STACK_R is defined, then at this point the
> > stack and global_data are relocated to below CONFIG_SPL_STACK_R_ADDR.
> >
> > CONFIG_SPL_STACK_R_ADDR - 0x80000 (this would be as part of sdram map)
> > CONFIG_SPL_STACK  - 0xff718000 (this address where SDRAM not been used)
> >
> > Since the issue, is due to launch U-Boot proper from mmc, the stack
> > that SPL during that time was not set it up.
>
> I think the root cause is: the master of emmc controller can no access
> SRAM, and the emmc init
> driver needs to use memory based on CONFIG_SPL_STACK, if this is in
> SRAM, then the emmc driver
> will init fail, and 'fifo-mode' can work around this issue. So the
> CONFIG_SPL_STACK_R is needed
> for emmc/sd controller driver.

Not sure, because tinker-rk3288 doesn't have eMMC.