[U-Boot] [PATCH 22/30] riscv: remove unused labels in start.S

[Auer, Lukas]

Hi Rick,

On Thu, 2018-10-25 at 15:56 +0000, Auer, Lukas wrote:
> Hi Rick,
> 
> On Thu, 2018-10-25 at 09:16 +0800, Rick Chen wrote:
> > Auer, Lukas <lukas.auer at aisec.fraunhofer.de> 於 2018年10月24日 週三
> > 下午10:14寫道：
> > > 
> > > Hi Rick,
> > > 
> > > On Wed, 2018-10-24 at 13:47 +0800, Rick Chen wrote:
> > > > Rick Chen <rickchen36 at gmail.com> 於 2018年10月24日 週三 下午1:20寫道：
> > > > > 
> > > > > Bin Meng <bmeng.cn at gmail.com> 於 2018年10月24日 週三 上午11:34寫道：
> > > > > > 
> > > > > > Hi Rich,
> > > > > > 
> > > > > > On Wed, Oct 24, 2018 at 10:37 AM Rick Chen <
> > > > > > rickchen36 at gmail.com>
> > > > > > wrote:
> > > > > > > 
> > > > > > > > > > The labels nmi_vector, trap_vector and handle_reset
> > > > > > > > > > in
> > > > > > > > > > start.S are not
> > > > > > > > > > used for RISC-V. Remove them.
> > > > > > > > > > 
> > > > > > > 
> > > > > > > Hi Lukas
> > > > > > > 
> > > > > > > Agree with the above part.
> > > > > > > 
> > > > > > > > > > While we are here, also remove the code from the
> > > > > > > > > > beginning of start.S,
> > > > > > > > > > which stores the contents of a2 to memory. Only
> > > > > > > > > > registers
> > > > > > > > > > a0 and a1
> > > > > > > > > > contain information from the previous boot stage.
> > > > > > > > > > There
> > > > > > > > > > is therefore
> > > > > > > > > > no reason for saving a2.
> > > > > > > 
> > > > > > > NOT agree with this part.
> > > > > > > Saving a2 is trying to support dynamically dtb pass at
> > > > > > > runtime.
> > > > > > > 
> > > > > > 
> > > > > > Could you please describe in more details on what the use
> > > > > > case is
> > > > > > here?
> > > > > > 
> > > > > 
> > > > > Hi Bin and Lukas
> > > > > 
> > > > > After I study [PATCH 24/30] riscv: save hart ID and device
> > > > > tree
> > > > > passed
> > > > > by prior boot stage.
> > > > > I found it is the same thing.
> > > > > I will accepted this patch.
> > > > > So this patch is
> > > > > 
> > > > > Reviewed-by: Rick Chen <rick at andestech.com>
> > > > > 
> > > > > But I shall send a patch to fix ax25-ae350 to work as well
> > > > > later.
> > > > > And it will be as below :
> > > > > 
> > > > > ax5-ae350.c
> > > > > void *board_fdt_blob_setup(void)
> > > > > {
> > > > > void **ptr = (void *)&prior_stage_fdt_address;
> > > > > if (fdt_magic(*ptr) == FDT_MAGIC)
> > > > > return (void *)*ptr;
> > > > > 
> > > > > return (void *)CONFIG_SYS_FDT_BASE;
> > > > > }
> > > > > 
> > > > 
> > > > Sorry!
> > > > 
> > > > I shall send a fixed patch as below:
> > > > riscv: ax25-ae350: use device tree passed by prior boot stage
> > > > 
> > > > --- a/configs/ax25-ae350_defconfig
> > > > +++ b/configs/ax25-ae350_defconfig
> > > > @@ -15,7 +15,7 @@ CONFIG_CMD_SF_TEST=y
> > > >  # CONFIG_CMD_SETEXPR is not set
> > > >  CONFIG_BOOTP_PREFER_SERVERIP=y
> > > >  CONFIG_CMD_CACHE=y
> > > > -CONFIG_OF_BOARD=y
> > > > +CONFIG_OF_PRIOR_STAGE=y
> > > > 
> > > > +++ b/board/AndesTech/ax25-ae350/ax25-ae350.c
> > > > @@ -64,15 +64,6 @@ ulong board_flash_get_legacy(ulong base, int
> > > > banknum, flash_info_t *info)
> > > >         return 0;
> > > >  }
> > > > 
> > > > -void *board_fdt_blob_setup(void)
> > > > -{
> > > > -       void **ptr = (void *)CONFIG_SYS_SDRAM_BASE;
> > > > -       if (fdt_magic(*ptr) == FDT_MAGIC)
> > > > -                       return (void *)*ptr;
> > > > -
> > > > -       return (void *)CONFIG_SYS_FDT_BASE;
> > > > -}
> > > > -
> > > > 
> > > > Rick
> > > > 
> > > 
> > > Sorry, I have missed your commit. Just to clarify, does the ax25
> > > pass
> > > the device tree in a2 instead of a1? In that case, my patch must
> > > be
> > > changed since it assumes the device tree to be in a1.
> > > Related to this, can I assume that a0 stores the hart ID?
> > > 
> > > If you want, I can add this patch to my series.
> > > 
> > 
> > Hi Lukas
> > 
> > Your patch is correct.
> > I will send out a patch to fix the mismatch in ax25-ae350 later.
> > And maybe you can put this patch into your v2 series.
> > 
> > Thanks
> > 
> > Rick
> > 
> 
> Ok. Yes, I will pick up your patch in my v2.
> 

Do you want me to wait with my patch series until it is clear how ax25-
ae350 handles the device tree? Otherwise, I will drop the part of this
patch that removes the code storing a2 to avoid breaking your board and
send v2 of my series.

Thanks,
Lukas