Re: [PATCH v2 0/3] PCI: brcmstb: CLKREQ# accomodations of downstream device

From: Florian Fainelli
Date: Thu Apr 13 2023 - 14:40:19 EST


On 4/11/23 09:59, Jim Quinlan wrote:
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.

Jim Quinlan (3):
PCI: brcmstb: CLKREQ# accomodations of downstream device
PCI: brcmstb: Set PCIe transaction completion timeout
blah blah

Tested-by: Florian Fainelli <f.fainelli@xxxxxxxxx>

On a 7216 system test with:

01:00.0 Network controller: Intel Corporation Wireless 7260 (rev 73)

and on the CM4 I/O board with:

01:00.0 Network controller: Intel Corporation Wireless 7260 (rev 73)

01:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection

01:00.0 Network controller: Broadcom Inc. and subsidiaries BCM43224 802.11a/b/g/n (rev 01)

01:00.0 SATA controller: Marvell Technology Group Ltd. 88SE9125 PCIe SATA 6.0 Gb/s controller (rev 11) (prog-if 01 [AHCI 1.0])

01:00.0 Ethernet controller: Broadcom Inc. and subsidiaries NetXtreme BCM5751 Gigabit Ethernet PCI Express (rev 21)

01:00.0 PCI bridge: PLX Technology, Inc. PEX8112 x1 Lane PCI Express-to-PCI Bridge (rev aa)
02:00.0 Multiport serial controller: Pepperl+Fuchs RocketPort EXPRESS 8-port w/Octa Cable

01:00.0 Ethernet controller: Qualcomm Atheros AR5008 Wireless Network Adapter (rev 01)

01:00.0 Network controller: Broadcom Inc. and subsidiaries BCM4311 802.11a/b/g (rev 01)

01:00.0 Network controller: Broadcom Inc. and subsidiaries BCM4322 802.11a/b/g/n Wireless LAN Controller (rev 01)

01:00.0 Network controller: Broadcom Inc. and subsidiaries BCM43602 802.11ac Wireless LAN SoC (rev 01)

and finally with a 4 port switch:

-[0000:00]---00.0-[01-07]----00.0-[02-07]--+-01.0-[03]----00.0 Intel Corporation 82574L Gigabit Network Connection

+-03.0-[04-05]----00.0-[05]----00.0 Pepperl+Fuchs RocketPort EXPRESS 8-port w/Octa Cable
+-05.0-[06]----00.0 Broadcom Inc. and subsidiaries NetXtreme BCM5751 Gigabit Ethernet PCI Express
\-07.0-[07]----00.0 Intel Corporation 82574L Gigabit Network Connection

And than I ran out of devices that I could plug, the others were x4, x8 or x16.

Most (all?) would previously fail, so definitively an improvement!

Thanks!
--
--
Florian