v7 -- Manivannan Sadhasivam suggested (a) making the property look like a
network phy-mode and (b) keeping the code simple (not counting clkreq
signal appearances, un-advertising capabilites, etc). This is
what I have done. The property is now "brcm,clkreq-mode" and
the values may be one of "safe", "default", and "no-l1ss". The
default setting is to employ the most capable power savings mode.
v6 -- No code has been changed.
-- Changed commit subject and comment in "#PERST" commit (Bjorn, Cyril)
-- Changed sign-off and author email address for all commits.
This was due to a change in Broadcom's upstreaming policy.
v5 -- Remove DT property "brcm,completion-timeout-us" from
"DT bindings" commit. Although this error may be reported
as a completion timeout, its cause was traced to an
internal bus timeout which may occur even when there is
no PCIe access being processed. We set a timeout of four
seconds only if we are operating in "L1SS CLKREQ#" mode.
-- Correct CEM 2.0 reference provided by HW engineer,
s/3.2.5.2.5/3.2.5.2.2/ (Bjorn)
-- Add newline to dev_info() string (Stefan)
-- Change variable rval to unsigned (Stefan)
-- s/implementaion/implementation/ (Bjorn)
-- s/superpowersave/powersupersave/ (Bjorn)
-- Slightly modify message on "PERST#" commit.
-- Rebase to torvalds master
v4 -- New commit that asserts PERST# for 2711/RPi SOCs at PCIe RC
driver probe() time. This is done in Raspian Linux and its
absence may be the cause of a failing test case.
-- New commit that removes stale comment.
v3 -- Rewrote commit msgs and comments refering panics if L1SS
is enabled/disabled; the code snippet that unadvertises L1SS
eliminates the panic scenario. (Bjorn)
-- Add reference for "400ns of CLKREQ# assertion" blurb (Bjorn)
-- Put binding names in DT commit Subject (Bjorn)
-- Add a verb to a commit's subject line (Bjorn)
-- s/accomodat(\w+)/accommodat$1/g (Bjorn)
-- Rewrote commit msgs and comments refering panics if L1SS
is enabled/disabled; the code snippet that unadvertises L1SS
eliminates the panic scenario. (Bjorn)
v2 -- Changed binding property 'brcm,completion-timeout-msec' to
'brcm,completion-timeout-us'. (StefanW for standard suffix).
-- Warn when clamping timeout value, and include clamped
region in message. Also add min and max in YAML. (StefanW)
-- Qualify description of "brcm,completion-timeout-us" so that
it refers to PCIe transactions. (StefanW)
-- Remvove mention of Linux specifics in binding description. (StefanW)
-- s/clkreq#/CLKREQ#/g (Bjorn)
-- Refactor completion-timeout-us code to compare max and min to
value given by the property (as opposed to the computed value).
v1 -- The current driver assumes the downstream devices can
provide CLKREQ# for ASPM. These commits accomodate devices
w/ or w/o clkreq# and also handle L1SS-capable devices.
-- The Raspian Linux folks have already been using a PCIe RC
property "brcm,enable-l1ss". These commits use the same
property, in a backward-compatible manner, and the implementaion
adds more detail and also automatically identifies devices w/o
a clkreq# signal, i.e. most devices plugged into an RPi CM4
IO board.
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