No description
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Martin Blumenstingl a29ae8600d clk: meson: meson8b: Don't rely on u-boot to init all GP_PLL registers
Not all u-boot versions initialize the HHI_GP_PLL_CNTL[2-5] registers.
In that case all HHI_GPLL_PLL_CNTL[1-5] registers are 0x0 and when
booting Linux the PLL fails to lock.
The initialization sequence from u-boot is:
- put the PLL into reset
- write 0x59C88000 to HHI_GP_PLL_CNTL2
- write 0xCA463823 to HHI_GP_PLL_CNTL3
- write 0x0286A027 to HHI_GP_PLL_CNTL4
- write 0x00003000 to HHI_GP_PLL_CNTL5
- set M, N, OD and the enable bit
- take the PLL out of reset
- check if it has locked
- disable the PLL

In Linux we already initialize M, N, OD, the enable and the reset bits.
Also the HHI_GP_PLL_CNTL[2-5] registers with these magic values (the
exact meaning is unknown) so the PLL can lock when the vendor u-boot did
not initialize these registers yet.

Fixes: b882964b37 ("clk: meson: meson8b: add support for the GP_PLL clock on Meson8m2")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20200501215717.735393-1-martin.blumenstingl@googlemail.com
History 2020-05-02 01:53:32 +02:00
arch
block
certs
crypto
Documentation
drivers
fs
include
init
ipc
kernel
lib
LICENSES
mm
net
samples
scripts
security
sound
tools
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.