CVS commit: src/sys/arch/arm/rockchip

["Tobias Nygren" <tnn%netbsd.org@localhost>]

Module Name:    src
Committed By:   tnn
Date:           Sun Oct 11 15:33:18 UTC 2020

Modified Files:
        src/sys/arch/arm/rockchip: rk3399_pcie.c

Log Message:
rk3399_pci: support for PCI express switches / bridges / multiple buses

There were two isses that prevented this from working:

1. We must use type 1 configuration cycles when accessing bus 2 and
beyond, but type 0 configuration cycles for bus 0 and 1.

2. The hardware address decoder cannot be used to decode the bus portion
of the ECAM address. Due to the physical SoC address of the remote device
region not having sufficient alignment the wrong bus address would go out
on the wire. Also the mapped region is too small to address busses
beyond bus31.

Fix: Reduce the number of ECAM translated bits to dev+func only.
For each configuration space access, acquire an exclusive lock
and reprogram the translator with the correct bus number and access type.
Config space is accessed sufficiently infrequent for this to not cause
any performance problems.


To generate a diff of this commit:
cvs rdiff -u -r1.11 -r1.12 src/sys/arch/arm/rockchip/rk3399_pcie.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.