[PATCH v4 14/29] efi: arm: Don't do the EL2 switch when running under EFI

[Simon Glass]

Hi Caleb,

On Thu, 27 Mar 2025 at 10:28, Caleb Connolly <caleb.connolly at linaro.org> wrote:
>
>
>
> On 2/15/25 04:22, Simon Glass wrote:
> > The previous bootloader has likely done this already, so avoid trying to
> > do it again. This fixes a crash in QEMU when booting from EDK2
> >
> > Signed-off-by: Simon Glass <sjg at chromium.org>
>
> ll_boot_init is a pretty unintuitive name tbh. skip_lowlevel_init()
> might be clearer?

The ll_boot_init() name has been there for ages. I didn't use
lowlevel_init as that symbols is widely used in ARM and it would be
too confusion. Perhaps bare_metal() ?

>
> off-topic, but how is EBS called?

Assuming that Linux is booted as an EFI app, by Linux. Otherwise, the
app currently doesn't work properly.

>
> Reviewed-by: Caleb Connolly <caleb.connolly at linaro.org>
> > ---
> >
> > (no changes since v1)
> >
> >   arch/arm/lib/bootm.c | 7 +++++--
> >   1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
> > index 974cbfe8400..688c2f3f29b 100644
> > --- a/arch/arm/lib/bootm.c
> > +++ b/arch/arm/lib/bootm.c
> > @@ -16,6 +16,7 @@
> >   #include <command.h>
> >   #include <cpu_func.h>
> >   #include <dm.h>
> > +#include <init.h>
> >   #include <log.h>
> >   #include <asm/global_data.h>
> >   #include <dm/root.h>
> > @@ -186,8 +187,10 @@ __weak void setup_board_tags(struct tag **in_params) {}
> >   #ifdef CONFIG_ARM64
> >   static void do_nonsec_virt_switch(void)
> >   {
> > -     smp_kick_all_cpus();
> > -     dcache_disable();       /* flush cache before swtiching to EL2 */
> > +     if (ll_boot_init()) {
> > +             smp_kick_all_cpus();
> > +             dcache_disable();       /* flush cache before swtiching to EL2 */
> > +     }
> >   }
> >   #endif
> >
>
> --
> Caleb (they/them)
>

Regards,
Simon