This is now clarified in an ACPI spec ECR (https://bugzilla.tianocore.org/show_bug.cgi?id=3335). The example will be updated in a future spec errata to use ResourceProducer.
I think this patch can resume as it is not gated by the spec anymore.
From: Andrei Warkentin <awarkentin@vmware.com>
Sent: Thursday, April 8, 2021 10:25 AM
To: Jeremy Linton <Jeremy.Linton@arm.com>; devel@edk2.groups.io
Cc: Ard Biesheuvel <Ard.Biesheuvel@arm.com>; leif@nuviainc.com; pete@akeo.ie; Samer El-Haj-Mahmoud <Samer.El-Haj-Mahmoud@arm.com>
Subject: Re: [PATCH 0/3] SD+USB perf/DMA fixes
I think Linux's behavior needs to be reconciled with the ACPI spec, which uses _DMA with ResourceConsumer, not ResourceProducer.
A
From: Jeremy Linton <jeremy.linton@arm.com>
Sent: Thursday, April 8, 2021 12:58 AM
To: devel@edk2.groups.io <devel@edk2.groups.io>
Cc: ard.biesheuvel@arm.com <ard.biesheuvel@arm.com>;
leif@nuviainc.com <leif@nuviainc.com>;
pete@akeo.ie <pete@akeo.ie>;
samer.el-haj-mahmoud@arm.com <samer.el-haj-mahmoud@arm.com>; Andrei Warkentin <awarkentin@vmware.com>;
Jeremy Linton <jeremy.linton@arm.com>
Subject: [PATCH 0/3] SD+USB perf/DMA fixes
A large part of why the emmc & dwc2 usb
controllers haven't been working properly is
because the "bus" _DMA was incorrectly tagged
as a consumer, when it needs to be a producer.
That is why linux has been dropping the
translation value portions of _DMA().
Since the emmc2 dma (with the old B0 SoC), and the
dwc2 is expected to work, lets add matching 30 bit
IORT entries for them.
Finally, in the shuffle the high speed cap bit override
was dropped from the linux patches, and I failed
to add it back to the firmware values, this caused
the wifi perf to be lower than it should have been.
Jeremy Linton (3):
Platform/RaspberryPi/Acpitables: Enable Arasan hispeed mode
Platform/RaspberryPi/AcpiTables: Add further named components
Platform/RaspberryPi/AcpiTables: Correct _DMA consumer
Platform/RaspberryPi/AcpiTables/Dsdt.asl | 2 +-
Platform/RaspberryPi/AcpiTables/Emmc.asl | 2 +-
Platform/RaspberryPi/AcpiTables/Iort.aslc | 44 ++++++++++++++++++++++++++++++-
Platform/RaspberryPi/AcpiTables/Sdhc.asl | 2 +-
4 files changed, 46 insertions(+), 4 deletions(-)
--
2.13.7