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Douglas Anderson f4033db5b8 clk: rockchip: undo several noc and special clocks as critical on rk3288
This is mostly a revert of commit 55bb6a633c ("clk: rockchip: mark
noc and some special clk as critical on rk3288") except that we're
keeping "pmu_hclk_otg0" as critical still.

NOTE: turning these clocks off doesn't seem to do a whole lot in terms
of power savings (checking the power on the logic rail).  It appears
to save maybe 1-2mW.  ...but still it seems like we should turn the
clocks off if they aren't needed.

About "pmu_hclk_otg0" (the one clock from the original commit we're
still keeping critical) from an email thread:

> pmu ahb clock
>
> Function: Clock to pmu module when hibernation and/or ADP is
> enabled. Must be greater than or equal to 30 MHz.
>
> If the SOC design does not support hibernation/ADP function, only have
> hclk_otg, this clk can be switched according to the usage of otg.
> If the SOC design support hibernation/ADP, has two clocks, hclk_otg and
> pmu_hclk_otg0.
> Hclk_otg belongs to the closed part of otg logic, which can be switched
> according to the use of otg.
>
> pmu_hclk_otg0 belongs to the always on part.
>
> As for whether pmu_hclk_otg0 can be turned off when otg is not in use,
> we have not tested. IC suggest make pmu_hclk_otg0 always on.

For the rest of the clocks:

atclk: No documentation about this clock other than that it goes to
the CPU.  CPU functions fine without it on.  Maybe needed for JTAG?

jtag: Presumably this clock is only needed if you're debugging with
JTAG.  It doesn't seem like it makes sense to waste power for every
rk3288 user.  In any case to do JTAG you'd need private patches to
adjust the pinctrl the mux the JTAG out anyway.

pclk_dbg, pclk_core_niu: On veyron Chromebooks we turn these two
clocks on only during kernel panics in order to access some coresight
registers.  Since nothing in the upstream kernel does this we should
be able to leave them off safely.  Maybe also needed for JTAG?

hsicphy12m_xin12m: There is no indication of why this clock would need
to be turned on for boards that don't use HSIC.

pclk_ddrupctl[0-1], pclk_publ0[0-1]: On veyron Chromebooks we turn
these 4 clocks on only when doing DDR transitions and they are off
otherwise.  I see no reason why they'd need to be on in the upstream
kernel which doesn't support DDRFreq.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Elaine Zhang <zhangqing@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2019-04-23 12:17:11 +02:00
Documentation Kbuild updates for v5.1 (2nd) 2019-03-17 13:25:26 -07:00
LICENSES LICENSES: Add GCC runtime library exception text 2019-01-16 14:54:15 -07:00
arch Kbuild updates for v5.1 (2nd) 2019-03-17 13:25:26 -07:00
block for-5.1/block-post-20190315 2019-03-16 12:36:39 -07:00
certs kexec, KEYS: Make use of platform keyring for signature verify 2019-02-04 17:34:07 -05:00
crypto lib/lzo: separate lzo-rle from lzo 2019-03-07 18:32:03 -08:00
drivers clk: rockchip: undo several noc and special clocks as critical on rk3288 2019-04-23 12:17:11 +02:00
fs Pull request for inlusion in 5.1 2019-03-17 09:10:56 -07:00
include Kbuild updates for v5.1 (2nd) 2019-03-17 13:25:26 -07:00
init init/main: add checks for the return value of memblock_alloc*() 2019-03-12 10:04:02 -07:00
ipc Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 14:08:19 -07:00
kernel pidfd patches for v5.1-rc1 2019-03-16 13:47:14 -07:00
lib Kbuild updates for v5.1 (2nd) 2019-03-17 13:25:26 -07:00
mm device-dax for 5.1 2019-03-16 13:05:32 -07:00
net Pull request for inlusion in 5.1 2019-03-17 09:10:56 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-11 08:54:01 -07:00
scripts kconfig: remove stale lxdialog/.gitignore 2019-03-17 15:47:02 +09:00
security selinux/stable-5.1 PR 20190312 2019-03-13 11:10:42 -07:00
sound sound fixes for 5.1-rc1 2019-03-15 14:05:00 -07:00
tools pidfd patches for v5.1-rc1 2019-03-16 13:47:14 -07:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt ARM: some cleanups, direct physical timer assignment, cache sanitization 2019-03-15 15:00:28 -07:00
.clang-format Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 13:43:42 -07:00
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COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Char/Misc driver patches for 5.1-rc1 2019-03-06 14:18:59 -08:00
Kbuild Kbuild updates for v5.1 2019-03-10 17:48:21 -07:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS ARM: some cleanups, direct physical timer assignment, cache sanitization 2019-03-15 15:00:28 -07:00
Makefile Linux 5.1-rc1 2019-03-17 14:22:26 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.