[PATCH v4 6/9] arm: Get bloblist from boot arguments

[Raymond Mao]

Hi Michal,

On Wed, 3 Jan 2024 at 05:46, Michal Simek <michal.simek at amd.com> wrote:

>
>
> On 1/2/24 23:12, Raymond Mao wrote:
> > Add arch custom function to get bloblist from boot arguments.
> > Check whether boot arguments aligns with the register conventions
> > defined in FW Handoff spec v0.9.
> > Add bloblist related options into qemu-arm default config.
> >
> > Signed-off-by: Raymond Mao <raymond.mao at linaro.org>
> > ---
> > Changes in v2
> > - Remove low level code for copying boot arguments.
> > - Refactor board_fdt_blob_setup() and remove direct access of
> gd->bloblist.
> > Changes in v3
> > - Optimize board_bloblist_from_boot_arg().
> > Changes in v4
> > - Move the function as an Arm-arch library instead of a board-specific
> one.
> >
> >   arch/arm/lib/xferlist.c      | 38 ++++++++++++++++++++++++++++++++++++
> >   configs/qemu_arm64_defconfig |  3 +++
> >   3 files changed, 45 insertions(+)
> >   create mode 100644 arch/arm/lib/xferlist.c
> >
> > diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
> > index b1bcd37466..0023c55d0d 100644
> > --- a/arch/arm/lib/Makefile
> > +++ b/arch/arm/lib/Makefile
> > @@ -85,6 +85,10 @@ obj-y      += psci-dt.o
> >
> >   obj-$(CONFIG_DEBUG_LL)      += debug.o
> >
> > +ifdef CONFIG_BLOBLIST
> > +obj-$(CONFIG_OF_BOARD)  += xferlist.o
> > +endif
> > +
> >   # For EABI conformant tool chains, provide eabi_compat()
> >   ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
> >   extra-y     += eabi_compat.o
> > diff --git a/arch/arm/lib/xferlist.c b/arch/arm/lib/xferlist.c
> > new file mode 100644
> > index 0000000000..163d20c11c
> > --- /dev/null
> > +++ b/arch/arm/lib/xferlist.c
> > @@ -0,0 +1,38 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright (C) 2023 Linaro Limited
> > + * Author: Raymond Mao <raymond.mao at linaro.org>
> > + */
> > +#include <linux/types.h>
> > +#include <errno.h>
> > +#include <bloblist.h>
> > +
> > +/*
> > + * Boot parameters saved from start.S
> > + * saved_args[0]: FDT base address
> > + * saved_args[1]: Bloblist signature
> > + * saved_args[2]: must be 0
> > + * saved_args[3]: Bloblist base address
> > + */
> > +extern unsigned long saved_args[];
>
> you should put this to bloblist.h. I would say it should be the part of
> 4/9
> where you define saved_args for armv7.
>
> Not sure if I understand your point but this part is for Arm only (v7 and
v8) and should
not be in bloblist.h. It works following the spec from Arm. Other arches
should implement
their own way if they want to load the bloblist from the previous loader.

[...]

Thanks and regards,
Raymond