[U-Boot] [PATCH] ARM64: zynqmp: Add support for standard distro boot commands

[Alexander Graf]

On 01.06.16 15:08, Michal Simek wrote:
> Nand and QSPI are not defined now but this will be extended.
> Based on selected bootmode boot_targets are rewritten.
> Patch also contains detection if variables are saved. If yes don't
> rewrite boot_targets variable.
> 
> Also move variable setup to the end of file because SCSI needs to be
> defined before others macros are using it.
> 
> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
> ---
> 
> Patch depends on
> "env: Setup GD_FLG_ENV_DEFAULT flag when default environment are used"
> 
> ---
>  board/xilinx/zynqmp/zynqmp.c    | 20 +++++++++-----
>  include/configs/xilinx_zynqmp.h | 59 ++++++++++++++++++++++++++++++-----------
>  2 files changed, 57 insertions(+), 22 deletions(-)
> 
> diff --git a/board/xilinx/zynqmp/zynqmp.c b/board/xilinx/zynqmp/zynqmp.c
> index 4623cd49e9c7..46c332215b6b 100644
> --- a/board/xilinx/zynqmp/zynqmp.c
> +++ b/board/xilinx/zynqmp/zynqmp.c
> @@ -215,6 +215,11 @@ int board_late_init(void)
>  	u32 reg = 0;
>  	u8 bootmode;
>  
> +	if (!(gd->flags & GD_FLG_ENV_DEFAULT)) {
> +		debug("Saved variables - Skipping\n");
> +		return 0;
> +	}
> +
>  	reg = readl(&crlapb_base->boot_mode);
>  	bootmode = reg & BOOT_MODES_MASK;
>  
> @@ -222,31 +227,32 @@ int board_late_init(void)
>  	switch (bootmode) {
>  	case JTAG_MODE:
>  		puts("JTAG_MODE\n");
> -		setenv("modeboot", "jtagboot");
> +		setenv("boot_targets", "pxe dhcp");

Is there a particular reason you're overwriting the boot_targets rather
than prepending them?

If I plug in an SD card with U-Boot on it, but my OS is on a SATA
attached disk (which is how I currently use the ZynqMP), this would set
the boot_targets to SD rather than "SD first, default list later".

If we instead do something like

  boot_targets = "pxe dhcp " + getenv(boot_targets);

we would maintain a workable fallback path. Yes, we might check a target
device twice, but since we know that it fails I don't think it's too
much of a problem.


Alex