Re: [Qemu-arm] [PATCH v2 04/11] hw/arm/aspeed: add a 'execute-in-place' property to boot directly from CE0

[Peter Maydell]

On 21 September 2018 at 17:19, Cédric Le Goater <address@hidden> wrote:
> The overhead for the OpenBMC firmware images using the a custom U-Boot
> is around 2 seconds, which is fine, but with a U-Boot from mainline,
> it takes an extra 50 seconds or so to reach Linux. A quick survey on
> the number of reads performed on the flash memory region gives the
> following figures :
>
>   OpenBMC U-Boot      922478 (~ 3.5 MBytes)
>   Mainline U-Boot   20569977 (~ 80  MBytes)
>
> QEMU must be trashing the TCG TBs and reloading text very often. Some
> addresses are read more than 250.000 times. Until we find a solution
> to improve boot time, execution from MMIO is not activated by default.
>
> Setting this option also breaks migration compatibility.
>
> Signed-off-by: Cédric Le Goater <address@hidden>

Reviewed-by: Peter Maydell <address@hidden>

thanks
-- PMM