Commit graph

7 commits

Author SHA1 Message Date
Bin Meng
5ae5aa9310 x86: acpi: Fix Windows S3 resume failure
U-Boot sets up the real mode interrupt handler stubs starting from
address 0x1000. In most cases, the first 640K (0x00000 - 0x9ffff)
system memory is reported as system RAM in E820 table to the OS.
(see install_e820_map() implementation for each platform). So OS
can use these memories whatever it wants.

If U-Boot is in an S3 resume path, care must be taken not to corrupt
these memorie otherwise OS data gets lost. Testing shows that, on
Microsoft Windows 10 on Intel Baytrail its wake up vector happens to
be installed at the same address 0x1000. While on Linux its wake up
vector does not overlap this memory range, but after resume kernel
checks low memory range per config option CONFIG_X86_RESERVE_LOW
which is 64K by default to see whether a memory corruption occurs
during the suspend/resume (it's harmless, but warnings are shown
in the kernel dmesg logs).

We cannot simply mark the these memory as reserved in E820 table
because such configuration makes GRUB complain: unable to allocate
real mode page. Hence we choose to back up these memories to the
place where we reserved on our stack for our S3 resume work.
Before jumping to OS wake up vector, we need restore the original
content there.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
2017-05-17 17:11:46 +08:00
Bin Meng
0f4e25887d x86: acpi: Refactor acpi_resume()
To do something more in acpi_resume() like turning on ACPI mode,
we need locate ACPI FADT table pointer first. But currently this
is done in acpi_find_wakeup_vector().

This changes acpi_resume() signature to accept ACPI FADT pointer
as the parameter. A new API acpi_find_fadt() is introduced, and
acpi_find_wakeup_vector() is updated to use FADT pointer as the
parameter as well.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
2017-05-17 17:11:46 +08:00
Bin Meng
3a34cae011 x86: acpi: Resume OS if resume vector is found
In an S3 resume path, U-Boot does everything like a cold boot except
in the last_stage_init() it jumps to the OS resume vector.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
2017-05-17 17:11:46 +08:00
Bin Meng
2b2d666f9c x86: acpi: Add wake up assembly stub
This adds a wake up stub before jumping to OS wake up vector.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
2017-05-17 17:11:46 +08:00
Bin Meng
b727961b07 x86: Store and display previous sleep state
Add one member in the global data to store previous sleep state,
and display the state during boot in print_cpuinfo().

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
2017-05-17 17:11:46 +08:00
Bin Meng
1206723b6e x86: fsp: acpi: Pass different boot mode to FSP init
When ACPI S3 resume is turned on, we should pass different boot mode
to FSP init instead of default BOOT_FULL_CONFIG.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
2017-05-17 17:11:46 +08:00
Bin Meng
4372c111d4 x86: acpi: Add Kconfig option and header file for ACPI resume
This introduces a Kconfig option for ACPI S3 resume, as well as a
header file to include anything related to ACPI S3 resume.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>
2017-05-17 17:11:46 +08:00