On 21 September 2018 at 17:19, Cédric Le Goater <[email protected]> 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 <[email protected]>
Reviewed-by: Peter Maydell <[email protected]> thanks -- PMM
