Contains:
1. Overview of Android Verified Boot 2.0
2. Description of avb subset of commands
3. Examples of errors when boot/vendor/system/vbmeta partitions
are tampered
4. Examples of enabling AVB2.0 on your setup

Signed-off-by: Igor Opaniuk <igor.opaniuk@linaro.org>

To avoid confusion, let's rename the efi-x86 target to efi-x86_app.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

It is possible to create a generic EFI payload for all x86 boards.
The payload is configured to include as many generic drivers as
possible. All stuff that touches low-level initialization are not
allowed as such is the EFI BIOS's responsibility. Platform specific
drivers (like gpio, spi, etc) are not included.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

At present the EFI application and payload support codes in the x86
directory is distributed in a hybrid way. For example, the Kconfig
options for both app and payload are in arch/x86/lib/efi/Kconfig,
but the source codes in the same directory get built only for
CONFIG_EFI_STUB.

This refactors the codes by consolidating all the EFI support codes
into arch/x86/cpu/efi, just like other x86 targets.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Since commit f3b5056c4e72 ("efi_loader: split README.efi into two
separate documents"), the original README.efi was renamed to
README.u-boot_on_efi, but x86 doc still refers to the old one.

This updates the x86 doc to reference both README.u-boot_on_efi and
README.uefi.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

Currently both pirq_reg_to_linkno() and pirq_linkno_to_reg() assume
consecutive PIRQ routing control registers. But this is not always
the case on some platforms. Introduce a new device tree property
intel,pirq-regmap to describe how the PIRQ routing register offset
is mapped to the link number and adjust the irq router driver to
utilize the mapping.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

As README.x86 already mentions, there are two SPI flashes mounted
on Intel Cougar Canyon 2 board, called SPI-0 and SPI-1 respectively.
SPI-0 stores the flash descriptor and the ME firmware. SPI-1 stores
the actual BIOS image which is U-Boot. Building a single image with
both ME firmware and U-Boot does not make sense.

This also describes the exact flash location where the u-boot.rom
should be programmed in the documentation.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

This commit removes text that is exact duplicated of the text above.

Cc: Konstantin Porotchkin <kostap@marvell.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Stefan Roese <sr@denx.de>