[PATCH v2 14/28] efi_loader: Install ACPI tables

[Simon Glass]

Hi Heinrich,

On Fri, 6 Sept 2024 at 04:56, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> On 9/6/24 09:22, Patrick Rudolph wrote:
> > Install ACPI tables inside the efi_loader similar to SMBIOS tables.
> > When ACPI is enabled and wasn't installed in other places, install
> > the ACPI table in EFI. Since EFI is necessary to pass the ACPI
> > table location when FDT isn't used, there's no need to install it
> > separately.
> >
> > When CONFIG_BLOBLIST_TABLES is set the tables will be stored in a
> > bloblist.
>
> The UEFI specification clearly describes how to hand over ACPI tables. I
> can't see why bloblists should be of any relevance in the UEFI context.
>
> >
> > TEST: Booted QEMU SBSA using EFI and ACPI only.
>
> With this description it is unclear if you used QFW to install ACPI
> tables which would not test the code below.
>
> >
> > Signed-off-by: Patrick Rudolph <patrick.rudolph at 9elements.com>
> > Cc: Simon Glass <sjg at chromium.org>
> > Cc: Tom Rini <trini at konsulko.com>
>
> Please, cc maintainers as reported by scripts/get_maintainers in future.
>
> > ---
> >   lib/efi_loader/efi_acpi.c        | 57 ++++++++++++++++++++++++++++++--
> >   test/py/tests/test_event_dump.py |  1 +
> >   2 files changed, 56 insertions(+), 2 deletions(-)
> >
> > diff --git a/lib/efi_loader/efi_acpi.c b/lib/efi_loader/efi_acpi.c
> > index 67bd7f8ca2..9262f21ea6 100644
> > --- a/lib/efi_loader/efi_acpi.c
> > +++ b/lib/efi_loader/efi_acpi.c
> > @@ -6,15 +6,23 @@
> >    */
> >
> >   #include <efi_loader.h>
> > -#include <log.h>
> > -#include <mapmem.h>
> >   #include <acpi/acpi_table.h>
> >   #include <asm/global_data.h>
> > +#include <asm/io.h>
> > +#include <bloblist.h>
> > +#include <linux/sizes.h>
> > +#include <linux/log2.h>
> > +#include <log.h>
> > +#include <malloc.h>
> > +#include <mapmem.h>
> >
> >   DECLARE_GLOBAL_DATA_PTR;
> >
> >   static const efi_guid_t acpi_guid = EFI_ACPI_TABLE_GUID;
> >
> > +enum {
> > +     TABLE_SIZE      = SZ_64K,
> > +};
> >   /*
> >    * Install the ACPI table as a configuration table.
> >    *
> > @@ -47,3 +55,48 @@ efi_status_t efi_acpi_register(void)
> >       return efi_install_configuration_table(&acpi_guid,
> >                                              (void *)(ulong)addr);
> >   }
> > +
>
> Please, provide a function description.
>
> > +static int install_acpi_table(void)
> > +{
> > +     u64 rom_addr, rom_table_end;
>
> There is no ROM involved here. Please, use meaningful variable names.
>
> > +     void *addr;
> > +
> > +     if (!IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE) ||
> > +         IS_ENABLED(CONFIG_X86) ||
> > +         IS_ENABLED(CONFIG_QFW_ACPI))
>
> Why would you want to call write_acpi_tables() twice on the sandbox? See
>
> board/sandbox/sandbox.c:180:
>              end = write_acpi_tables(addr);
>
> We should remove the redundant code from board/sandbox/sandbox.c with
> this patch.
>
> > +             return 0;
> > +
> > +     /* Align the table to a 4KB boundary to keep EFI happy */
> > +     if (IS_ENABLED(CONFIG_BLOBLIST_TABLES))
> > +             addr = bloblist_add(BLOBLISTT_ACPI_TABLES, TABLE_SIZE,
> > +                                 ilog2(SZ_4K));
> > +     else
> > +             addr = memalign(SZ_4K, TABLE_SIZE);
>
> The UEFI specification wants ACPI tables to reside in
> EfiACPIReclaimMemory. Neither bloblist_add() nor memalign() should be
> used here.

I just want to address this and something below.

We do want to put tables in a bloblist. This is how x86 works
(although I haven't gone back and cleaned up all the boards) and I
think we should do it for all archs.

The memalign() here is fine too, since the actual setting of EFI
memory type is done later, when the table is registered.

>
> > +
> > +     if (!addr)
> > +             return log_msg_ret("mem", -ENOBUFS);
> > +
> > +     rom_addr = virt_to_phys(addr);
> > +
> > +     gd->arch.table_start_high = rom_addr;
> > +
> > +     rom_table_end = write_acpi_tables(rom_addr);
> > +     if (!rom_table_end) {
> > +             log_err("Can't create ACPI configuration table\n");
> > +             return -EINTR;
> > +     }
> > +
> > +     debug("- wrote 'acpi' to %llx, end %llx\n", rom_addr, rom_table_end);
>
> Please, use log_debug().
>
> > +     if (rom_table_end - rom_addr > TABLE_SIZE) {
> > +             log_err("Out of space for configuration tables: need %llx, have %x\n",
>
> This check is too late. We must ensure that write_acpi_table() does not
> overwrite unallocated memory.

That is not supported at present, unfortunately. I agree we should fix
it, but not in this series. For now we can set a size of 64KB which
should be plenty. The same bug exists in x86.

>
> > +                     rom_table_end - rom_addr, TABLE_SIZE);
> > +             return log_msg_ret("acpi", -ENOSPC);
> > +     }
> > +     gd->arch.table_end_high = rom_table_end;
> > +
> > +     debug("- done writing tables\n");
>
> ditto
>
> Best regards
>
> Heinrich
>
> > +
> > +     return 0;
> > +}
> > +
> > +EVENT_SPY_SIMPLE(EVT_LAST_STAGE_INIT, install_acpi_table);
> > diff --git a/test/py/tests/test_event_dump.py b/test/py/tests/test_event_dump.py
> > index e282c67335..88bbf34f71 100644
> > --- a/test/py/tests/test_event_dump.py
> > +++ b/test/py/tests/test_event_dump.py
> > @@ -18,6 +18,7 @@ def test_event_dump(u_boot_console):
> >   --------------------  ------------------------------  ------------------------------
> >   EVT_FT_FIXUP          bootmeth_vbe_ft_fixup           .*boot/vbe_request.c:.*
> >   EVT_FT_FIXUP          bootmeth_vbe_simple_ft_fixup    .*boot/vbe_simple_os.c:.*
> > +EVT_LAST_STAGE_INIT   install_acpi_table              .*lib/efi_loader/efi_acpi.c:.*
> >   EVT_LAST_STAGE_INIT   install_smbios_table            .*lib/efi_loader/efi_smbios.c:.*
> >   EVT_MISC_INIT_F       sandbox_early_getopt_check      .*arch/sandbox/cpu/start.c:.*
> >   EVT_TEST              h_adder_simple                  .*test/common/event.c:'''
>

Regards,
Simon