[PATCH v2 1/4] x86: fsp: Allow skipping init code when chain loading

[Simon Glass]

Hi Bin,

On Sat, 29 Feb 2020 at 02:16, Bin Meng <bmeng.cn at gmail.com> wrote:
>
> Hi Simon,
>
> On Wed, Feb 19, 2020 at 10:46 AM Simon Glass <sjg at chromium.org> wrote:
> >
> > It is useful to be able to boot the same x86 image on a device with or
> > without a first-stage bootloader. For example, with chromebook_coral, it
> > is helpful for testing to be able to boot the same U-Boot (complete with
> > FSP) on bare metal and from coreboot. It allows checking of things like
> > CPU speed, comparing registers, ACPI tables and the like.
> >
> > When U-Boot is not the first-stage bootloader much of this code is not
> > needed and can break booting. Add checks for this to the FSP code.
> >
> > Rather than checking for the amount of available SDRAM, just use 1GB in
> > this situation, which should be safe. Using 2GB may run into a memory
> > hole on some SoCs.
> >
> > Signed-off-by: Simon Glass <sjg at chromium.org>
> > ---
> >
> > Changes in v2: None
> >
> >  arch/x86/lib/fsp/fsp_dram.c     |  8 ++++++++
> >  arch/x86/lib/fsp/fsp_graphics.c |  3 +++
> >  arch/x86/lib/fsp2/fsp_dram.c    | 10 ++++++++++
> >  arch/x86/lib/fsp2/fsp_init.c    |  2 +-
> >  4 files changed, 22 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/lib/fsp/fsp_dram.c b/arch/x86/lib/fsp/fsp_dram.c
> > index 9ce0ddf0d3..15e82de2fe 100644
> > --- a/arch/x86/lib/fsp/fsp_dram.c
> > +++ b/arch/x86/lib/fsp/fsp_dram.c
> > @@ -44,6 +44,14 @@ int dram_init_banksize(void)
> >         phys_addr_t low_end;
> >         uint bank;
> >
> > +       if (!ll_boot_init()) {
> > +               gd->bd->bi_dram[0].start = 0;
> > +               gd->bd->bi_dram[0].size = gd->ram_size;
> > +
> > +               mtrr_add_request(MTRR_TYPE_WRBACK, 0, gd->ram_size);
> > +               return 0;
> > +       }
> > +
> >         low_end = 0;
> >         for (bank = 1, hdr = gd->arch.hob_list;
> >              bank < CONFIG_NR_DRAM_BANKS && !end_of_hob(hdr);
> > diff --git a/arch/x86/lib/fsp/fsp_graphics.c b/arch/x86/lib/fsp/fsp_graphics.c
> > index 226c7e66b3..98b762209f 100644
> > --- a/arch/x86/lib/fsp/fsp_graphics.c
> > +++ b/arch/x86/lib/fsp/fsp_graphics.c
> > @@ -78,6 +78,9 @@ static int fsp_video_probe(struct udevice *dev)
> >         struct vesa_mode_info *vesa = &mode_info.vesa;
> >         int ret;
> >
> > +       if (!ll_boot_init())
> > +               return 0;
> > +
> >         printf("Video: ");
> >
> >         /* Initialize vesa_mode_info structure */
> > diff --git a/arch/x86/lib/fsp2/fsp_dram.c b/arch/x86/lib/fsp2/fsp_dram.c
> > index 90a238a224..74835eebce 100644
> > --- a/arch/x86/lib/fsp2/fsp_dram.c
> > +++ b/arch/x86/lib/fsp2/fsp_dram.c
> > @@ -12,11 +12,18 @@
> >  #include <asm/fsp/fsp_support.h>
> >  #include <asm/fsp2/fsp_api.h>
> >  #include <asm/fsp2/fsp_internal.h>
> > +#include <linux/sizes.h>
> >
> >  int dram_init(void)
> >  {
> >         int ret;
> >
> > +       if (!ll_boot_init()) {
> > +               /* Use a small and safe amount of 1GB */
> > +               gd->ram_size = SZ_1G;
> > +
> > +               return 0;
> > +       }
> >         if (spl_phase() == PHASE_SPL) {
> >  #ifdef CONFIG_HAVE_ACPI_RESUME
> >                 bool s3wake = gd->arch.prev_sleep_state == ACPI_S3;
> > @@ -68,6 +75,9 @@ int dram_init(void)
> >
> >  ulong board_get_usable_ram_top(ulong total_size)
> >  {
> > +       if (!ll_boot_init())
> > +               return gd->ram_size;
> > +
> >  #if CONFIG_IS_ENABLED(HANDOFF)
> >         struct spl_handoff *ho = gd->spl_handoff;
> >
> > diff --git a/arch/x86/lib/fsp2/fsp_init.c b/arch/x86/lib/fsp2/fsp_init.c
> > index da9bd6b45c..c7dc2ea257 100644
> > --- a/arch/x86/lib/fsp2/fsp_init.c
> > +++ b/arch/x86/lib/fsp2/fsp_init.c
> > @@ -23,7 +23,7 @@ int arch_cpu_init_dm(void)
> >         int ret;
> >
> >         /* Make sure pads are set up early in U-Boot */
> > -       if (spl_phase() != PHASE_BOARD_F)
> > +       if (!ll_boot_init() || spl_phase() != PHASE_BOARD_F)
> >                 return 0;
> >
> >         /* Probe all pinctrl devices to set up the pads */
> > --
>
> I assume the proposed ll_boot_init() debug only works with FSP2, right?
>
> I still would like to use the gd->flags instead of ll_boot_init().
>
> Besides, I think the x86 doc need be updated to describe the purpose
> and usage, using one board as an example.

OK I ill take a look and see if I can detect booting from coreboot at
least, and set the flag.

BTW what is next with the ACPI series?

Regards,
Simon