[PATCH v3 14/30] efi_loader: Allocate and write ACPI tables

Heinrich Schuchardt xypron.glpk at gmx.de
Thu Sep 19 14:46:17 CEST 2024


On 12.09.24 02:58, Simon Glass wrote:
> Hi Patrick,
>
> On Wed, 11 Sept 2024 at 00:25, Patrick Rudolph
> <patrick.rudolph at 9elements.com> wrote:
>>
>> Allocate memory for ACPI tables inside the efi_loader and write out
>> the tables 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 tables are still passed to the OS using EFI.
>>
>> This allows non x86 platforms to boot using ACPI only in case the
>> EFI loader is being used.
>>
>> TEST: Booted QEMU SBSA (no QFW) using EFI and ACPI only.
>>
>> Signed-off-by: Patrick Rudolph <patrick.rudolph at 9elements.com>
>> Cc: Simon Glass <sjg at chromium.org>
>> Cc: Tom Rini <trini at konsulko.com>
>> ---
>> Changelog v3:
>> - Drop memalign and use efi_allocate_pages
>> - Use log_debug instead of debug
>> - Clarify commit message
>> - Skip writing ACPI tables on sandbox
>> - Rename function
>> - Add function comment
>> ---
>>   lib/efi_loader/efi_acpi.c        | 80 +++++++++++++++++++++++++++++++-
>>   test/py/tests/test_event_dump.py |  1 +
>>   2 files changed, 79 insertions(+), 2 deletions(-)
>>
>> diff --git a/lib/efi_loader/efi_acpi.c b/lib/efi_loader/efi_acpi.c
>> index 67bd7f8ca2..9d38d0060c 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 +55,71 @@ efi_status_t efi_acpi_register(void)
>>          return efi_install_configuration_table(&acpi_guid,
>>                                                 (void *)(ulong)addr);
>>   }
>> +
>> +/*
>> + * Allocate memory for ACPI tables and write ACPI tables to the
>> + * allocated buffer.
>> + *
>> + * Return:     status code
>> + */
>> +static int alloc_write_acpi_tables(void)
>> +{
>> +       u64 table_addr, table_end;
>> +       u64 new_acpi_addr = 0;
>> +       efi_uintn_t pages;
>> +       efi_status_t ret;
>> +       void *addr;
>> +
>> +       if (!IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE))
>> +               return 0;
>> +
>> +       if (IS_ENABLED(CONFIG_X86) ||
>> +           IS_ENABLED(CONFIG_QFW_ACPI) ||
>> +           IS_ENABLED(CONFIG_SANDBOX)) {
>> +               log_debug("Skipping writing ACPI tables as already done\n");
>> +               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));
>> +
>> +               if (!addr)
>> +                       return log_msg_ret("mem", -ENOMEM);
>> +       } else {
>> +               pages = efi_size_in_pages(TABLE_SIZE);
>> +
>> +               ret = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES,
>> +                                        EFI_ACPI_RECLAIM_MEMORY,
>> +                                        pages, &new_acpi_addr);
>
> I know we are going to have a problem here since EFI memory-allocation
> is a bit of a mess, and you got conflicting advice on the previous
> version....
>
> But we cannot call efi_allocate_pages() during U-Boot init. EFI may
> not even be enabled. The allocation ends up being in the area between
> the bottom of memory at the bottom of the stack, which is not supposed
> to be used, at least until images are loaded.

Please, have a look at init_sequence_r[].

The memory allocate for the EFI sub-system is initialized in
efi_memory_init directly after initr_lmb.

So for sure we can and should use efi_allocate_pages() here.

We must not use bloblist_add() as the memory allocation would not be
reported as AcpiReclaimMemory.

Best regards

Heinrich

>
> I think in fact we should make this ACPI stuff depend on bloblist and
> just put the tables there. So set up bloblist size to something small,
> like 0x100 and set BLOBLIST_SIZE_RELOC to larger than you need (e.g.
> 68KB). Everything should work OK. I will do a bit of a tidy-up after
> this series goes in.
>
>> +               if (ret != EFI_SUCCESS)
>> +                       return log_msg_ret("mem", -ENOMEM);
>> +
>> +               addr = (void *)(uintptr_t)new_acpi_addr;
>> +       }
>> +
>> +       table_addr = virt_to_phys(addr);
>> +
>> +       gd->arch.table_start_high = table_addr;
>> +
>> +       table_end = write_acpi_tables(table_addr);
>> +       if (!table_end) {
>> +               log_err("Can't create ACPI configuration table\n");
>> +               return -EINTR;
>> +       }
>> +
>> +       log_debug("- wrote 'acpi' to %llx, end %llx\n", table_addr, table_end);
>> +       if (table_end - table_addr > TABLE_SIZE) {
>> +               log_err("Out of space for configuration tables: need %llx, have %x\n",
>> +                       table_end - table_addr, TABLE_SIZE);
>> +               return log_msg_ret("acpi", -ENOSPC);
>> +       }
>> +       gd->arch.table_end_high = table_end;
>> +
>> +       log_debug("- done writing tables\n");
>> +
>> +       return 0;
>> +}
>> +
>> +EVENT_SPY_SIMPLE(EVT_LAST_STAGE_INIT, alloc_write_acpi_tables);
>> diff --git a/test/py/tests/test_event_dump.py b/test/py/tests/test_event_dump.py
>> index e282c67335..459bfa26bb 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   alloc_write_acpi_tables         .*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:'''
>> --
>> 2.46.0
>>
>
> Regards,
> Simon



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