Re: [PATCH v6 04/10] arm_ffa: efi: unmap RX/TX buffers

Abdellatif El Khlifi
2022-11-08T10:48:56Z

On Mon, Oct 24, 2022 at 03:08:53PM +0300, Ilias Apalodimas wrote:
> On Thu, Oct 13, 2022 at 11:38:51AM +0100, Abdellatif El Khlifi wrote:
> > unmap RX/TX buffers at ExitBootServices()
> >
> > Unmapping the RX/TX buffers created by u-boot is needed before EFI
> > runtime.
> >
> > At EFI runtime the linux kernel takes care of allocating its own RX/TX
> > buffers and registering them with the secure world.
> >
> > Secure world should be using the RX/TX buffers created by the kernel.
> > So, RX/TX buffers created by u-boot must be unmapped.
> >
> > Signed-off-by: Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
> > Cc: Tom Rini <trini@konsulko.com>
> > Cc: Simon Glass <sjg@chromium.org>
> > Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
> > Cc: Jens Wiklander <jens.wiklander@linaro.org>
> > ---
> > lib/efi_loader/efi_boottime.c | 15 +++++++++++++++
> > 1 file changed, 15 insertions(+)
> >
> > diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
> > index a56021559b..2054b33568 100644
> > --- a/lib/efi_loader/efi_boottime.c
> > +++ b/lib/efi_loader/efi_boottime.c
> > @@ -3,6 +3,9 @@
> > * EFI application boot time services
> > *
> > * Copyright (c) 2016 Alexander Graf
> > + *
> > + * (C) Copyright 2022 ARM Limited
> > + * Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
> > */
> >
> > #include <common.h>
> > @@ -23,6 +26,10 @@
> > #include <asm/setjmp.h>
> > #include <linux/libfdt_env.h>
> >
> > +#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
> > +#include <arm_ffa.h>
> > +#endif
> > +
> > DECLARE_GLOBAL_DATA_PTR;
> >
> > /* Task priority level */
> > @@ -2178,6 +2185,14 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
> > dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);
> > }
> >
> > +#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
> > + /* unmap FF-A RX/TX buffers */
> > + if (ffa_bus_ops_get()->rxtx_unmap())
> > + debug("[efi_boottime][ERROR]: can not unmap FF-A RX/TX buffers\n");
>
> Just do log_err() here and get rid of the else

Thanks. Done in v7.

>
> > + else
> > + debug("[efi_boottime][INFO]: FF-A RX/TX buffers unmapped\n");
> > +#endif
> > +
> > /* Patch out unsupported runtime function */
> > efi_runtime_detach();
> >
> > --
> > 2.17.1
> >
>
> Thanks
> /Ilias