Hi, Rafael,
Gentle ping for this patch.
Thanks.
Shunyong.
On 2018/12/18 14:02, Yang, Shunyong wrote:
> In some scenario, we need to build initrd with kernel in a single image.
> This can simplify system deployment process by downloading the whole system
> once, such as in IC verification.
>
> This patch adds support to override ACPI tables from built-in initrd.
>
> Cc: Joey Zheng <yu.zheng@xxxxxxxxxxxxxxxx>
> Signed-off-by: Shunyong Yang <shunyong.yang@xxxxxxxxxxxxxxxx>
> ---
> v2: change "upgrade" to "override" as it's more accurate
> ---
> Documentation/acpi/initrd_table_override.txt | 4 ++++
> drivers/acpi/Kconfig | 10 ++++++++++
> drivers/acpi/tables.c | 12 ++++++++++--
> include/linux/initrd.h | 3 +++
> 4 files changed, 27 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/acpi/initrd_table_override.txt b/Documentation/acpi/initrd_table_override.txt
> index eb651a6aa285..324d5fb90a22 100644
> --- a/Documentation/acpi/initrd_table_override.txt
> +++ b/Documentation/acpi/initrd_table_override.txt
> @@ -14,6 +14,10 @@ upgrade the ACPI execution environment that is defined by the ACPI tables
> via upgrading the ACPI tables provided by the BIOS with an instrumented,
> modified, more recent version one, or installing brand new ACPI tables.
>
> +When building initrd with kernel in a single image, option
> +ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD should also be true for this
> +purpose.
> +
> For a full list of ACPI tables that can be upgraded/installed, take a look
> at the char *table_sigs[MAX_ACPI_SIGNATURE]; definition in
> drivers/acpi/tables.c.
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index 7cea769c37df..3b362a1c7685 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -357,6 +357,16 @@ config ACPI_TABLE_UPGRADE
> initrd, therefore it's safe to say Y.
> See Documentation/acpi/initrd_table_override.txt for details
>
> +config ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD
> + bool "Override ACPI tables from built-in initrd"
> + depends on ACPI_TABLE_UPGRADE
> + depends on INITRAMFS_SOURCE!="" && INITRAMFS_COMPRESSION=""
> + def_bool n
> + help
> + This option provides functionality to override arbitrary ACPI tables
> + from built-in uncompressed initrd.
> + See Documentation/acpi/initrd_table_override.txt for details
> +
> config ACPI_DEBUG
> bool "Debug Statements"
> help
> diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
> index 61203eebf3a1..f6a2c5ebabcd 100644
> --- a/drivers/acpi/tables.c
> +++ b/drivers/acpi/tables.c
> @@ -473,14 +473,22 @@ static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
>
> void __init acpi_table_upgrade(void)
> {
> - void *data = (void *)initrd_start;
> - size_t size = initrd_end - initrd_start;
> + void *data;
> + size_t size;
> int sig, no, table_nr = 0, total_offset = 0;
> long offset = 0;
> struct acpi_table_header *table;
> char cpio_path[32] = "kernel/firmware/acpi/";
> struct cpio_data file;
>
> + if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
> + data = __initramfs_start;
> + size = __initramfs_size;
> + } else {
> + data = (void *)initrd_start;
> + size = initrd_end - initrd_start;
> + }
> +
> if (data == NULL || size == 0)
> return;
>
> diff --git a/include/linux/initrd.h b/include/linux/initrd.h
> index 84b423044088..02d94aae54c7 100644
> --- a/include/linux/initrd.h
> +++ b/include/linux/initrd.h
> @@ -22,3 +22,6 @@
> extern void free_initrd_mem(unsigned long, unsigned long);
>
> extern unsigned int real_root_dev;
> +
> +extern char __initramfs_start[];
> +extern unsigned long __initramfs_size;
>
