x86: zImage: Propagate acpi_rsdp_addr to kernel via boot parameters
authorAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Wed, 10 Jan 2018 17:40:15 +0000 (19:40 +0200)
committerBin Meng <bmeng.cn@gmail.com>
Tue, 30 Jan 2018 06:29:07 +0000 (14:29 +0800)
commit3469bf4274540d1491d58e878a9edc0bdcba17ac
treef174ac3c22a5d8535cf74ef86642a39dd8183155
parent378960d8c2c72c5b6be2a6cd7787cab8c3ba5abc
x86: zImage: Propagate acpi_rsdp_addr to kernel via boot parameters

New field acpi_rsdp_addr, which has been introduced in boot protocol
v2.14 [1], in boot parameters tells kernel the exact address of RDSP
ACPI table. Knowing it increases robustness of the kernel by avoiding
in some cases traversal through a part of physical memory.
It will slightly reduce boot time by the same reason.

[1] See Linux kernel commit

  2f74cbf ("x86/boot: Add the ACPI RSDP address to struct setup_header::acpi_rdsp_addr")
  @ https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=2f74cbf

for the details.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
[bmeng: updated the kernel commit git URL and fixed one style issue]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
arch/x86/include/asm/bootparam.h
arch/x86/lib/acpi_table.c
arch/x86/lib/acpi_table.h [new file with mode: 0644]
arch/x86/lib/zimage.c