[U-Boot] [PATCH 3/5] efi_loader: Install ACPI configuration tables

[Alexander Graf]

On 06/24/2018 12:12 PM, Heinrich Schuchardt wrote:
> /On 06/23/2018 12:03 PM, Bin Meng wrote:
>> ACPI tables can be passed via EFI configuration table to an EFI
>> application. This is only supported on x86 so far.
>>
>> Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
>> ---
>>
>>   cmd/bootefi.c             |  5 +++++
>>   include/efi_api.h         |  8 ++++++++
>>   include/efi_loader.h      |  8 ++++++++
>>   lib/efi_loader/Makefile   |  1 +
>>   lib/efi_loader/efi_acpi.c | 42 ++++++++++++++++++++++++++++++++++++++++++
>>   5 files changed, 64 insertions(+)
>>   create mode 100644 lib/efi_loader/efi_acpi.c
>>
>> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
>> index f55a40d..cd755b6 100644
>> --- a/cmd/bootefi.c
>> +++ b/cmd/bootefi.c
>> @@ -61,6 +61,11 @@ efi_status_t efi_init_obj_list(void)
>>   	if (ret != EFI_SUCCESS)
>>   		goto out;
>>   #endif
>> +#ifdef CONFIG_GENERATE_ACPI_TABLE
>> +	ret = efi_acpi_register();
>> +	if (ret != EFI_SUCCESS)
>> +		goto out;
>> +#endif
>>   #ifdef CONFIG_GENERATE_SMBIOS_TABLE
>>   	ret = efi_smbios_register();
>>   	if (ret != EFI_SUCCESS)
>> diff --git a/include/efi_api.h b/include/efi_api.h
>> index 094be6e..69dcbac 100644
>> --- a/include/efi_api.h
>> +++ b/include/efi_api.h
>> @@ -286,6 +286,14 @@ struct efi_runtime_services {
>>   	EFI_GUID(0xeb9d2d31, 0x2d88, 0x11d3,  \
>>   		 0x9a, 0x16, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
>>   
>> +#define ACPI_TABLE_GUID \
>> +	EFI_GUID(0xeb9d2d30, 0x2d88, 0x11d3, \
>> +		 0x9a, 0x16, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
>> +
>> +#define ACPI_20_TABLE_GUID \
>> +	EFI_GUID(0x8868e871, 0xe4f1, 0x11d3, \
>> +		 0xbc, 0x22, 0x00, 0x80, 0xc7, 0x3c, 0x88, 0x81)
>> +
>>   struct efi_configuration_table
>>   {
>>   	efi_guid_t guid;
>> diff --git a/include/efi_loader.h b/include/efi_loader.h
>> index c66252a..d837e7b 100644
>> --- a/include/efi_loader.h
>> +++ b/include/efi_loader.h
>> @@ -215,6 +215,14 @@ efi_status_t efi_net_register(void);
>>   efi_status_t efi_watchdog_register(void);
>>   /* Called by bootefi to make SMBIOS tables available */
>>   /**
>> + * efi_acpi_register() - write out ACPI tables
>> + *
>> + * Called by bootefi to make ACPI tables available
>> + *
>> + * @return 0 if OK, -ENOMEM if no memory is available for the tables
>> + */
>> +efi_status_t efi_acpi_register(void);
>> +/**
>>    * efi_smbios_register() - write out SMBIOS tables
>>    *
>>    * Called by bootefi to make SMBIOS tables available
>> diff --git a/lib/efi_loader/Makefile b/lib/efi_loader/Makefile
>> index c6046e3..d6402c4 100644
>> --- a/lib/efi_loader/Makefile
>> +++ b/lib/efi_loader/Makefile
>> @@ -22,4 +22,5 @@ obj-$(CONFIG_LCD) += efi_gop.o
>>   obj-$(CONFIG_DM_VIDEO) += efi_gop.o
>>   obj-$(CONFIG_PARTITIONS) += efi_disk.o
>>   obj-$(CONFIG_NET) += efi_net.o
>> +obj-$(CONFIG_GENERATE_ACPI_TABLE) += efi_acpi.o
>>   obj-$(CONFIG_GENERATE_SMBIOS_TABLE) += efi_smbios.o
>> diff --git a/lib/efi_loader/efi_acpi.c b/lib/efi_loader/efi_acpi.c
>> new file mode 100644
>> index 0000000..b09292c
>> --- /dev/null
>> +++ b/lib/efi_loader/efi_acpi.c
>> @@ -0,0 +1,42 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + *  EFI application ACPI tables support
>> + *
>> + *  Copyright (C) 2018, Bin Meng <bmeng.cn at gmail.com>
>> + */
>> +
>> +#include <common.h>
>> +#include <efi_loader.h>
>> +#include <asm/acpi_table.h>
>> +
>> +static const efi_guid_t acpi_guid = ACPI_20_TABLE_GUID;
>> +
>> +/*
>> + * Install the ACPI table as a configuration table.
>> + *
>> + * @return	status code
>> + */
>> +efi_status_t efi_acpi_register(void)
>> +{
>> +	/* Map within the low 32 bits, to allow for 32bit ACPI tables */
>> +	u64 acpi = U32_MAX;
>> +	efi_status_t ret;
>> +
>> +	/* Reserve 64kiB page for ACPI */
>> +	ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
>> +				 EFI_RUNTIME_SERVICES_DATA, 16, &acpi);
>> +	if (ret != EFI_SUCCESS)
>> +		return ret;
>> +
>> +	/*
>> +	 * Generate ACPI tables - we know that efi_allocate_pages() returns
>> +	 * a 4k-aligned address, so it is safe to assume that
>> +	 * write_acpi_tables() will write the table at that address.
>> +	 */
>> +	assert(!(acpi & 0xf));
>> +	write_acpi_tables(acpi);
>> +
>> +	/* And expose them to our EFI payload */
>> +	return efi_install_configuration_table(&acpi_guid,
>> +					       (void *)(uintptr_t)acpi);
> The maximum number of configuration tables is currently hard coded as 2
> in efi_boottime.c. I think this limit should be raised. 16 seems
> reasonable looking at which tables the Linux EFI stub or iPXE can process.

How about we just move efi_conf_table from .bss into something 
dynamically allocated? If we wanted to keep things simple, we could even 
just always allocate a full page on the first invocation of 
efi_install_configuration_table() and just check against that size limit 
going forward.


Alex