From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gregory CLEMENT Subject: [PATCH v2 0/4] Add system mmu support for Armada-806 Date: Thu, 11 Jul 2019 17:02:38 +0200 Message-ID: <20190711150242.25290-1-gregory.clement@bootlin.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Robin Murphy , Joerg Roedel , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Cc: Rob Herring , devicetree@vger.kernel.org, Jason Cooper , Andrew Lunn , Sebastian Hesselbarth , Gregory CLEMENT , Thomas Petazzoni , linux-arm-kernel@lists.infradead.org, Catalin Marinas , Will Deacon , Antoine Tenart , =?UTF-8?q?Miqu=C3=A8l=20Raynal?= , Maxime Chevallier , Nadav Haklai List-Id: devicetree@vger.kernel.org Hello, last year a first version of this series was submitted to add support for IOMMU for AP806, including workaround for accessing ARM SMMU 64bit registers[1]. For the record, AP-806 can't access SMMU registers with 64bit width, this patches split the readq/writeq for 32bit access, due to erratanum #582743. Based on the feedback from Robin Murphy, I also add code ensuring that we won't try to use AArch64 format with 32 bits acces. It was also discussed to not use compatible but propertu to support this workaround. I agree to make this change if needed, but for now I would like to have a feedback on the current code to know if it is acceptable if there is still potential issue. The series was tested on a vanilla v5.1 kernel, and without the series, an USB stick was not detected under QEMU whereas with this series it worked as expected. Greogry [1]: https://lkml.org/lkml/2018/10/15/373 Gregory CLEMENT (1): arm64: dts: marvell: armada-ap806: add smmu support Hanna Hawa (3): iommu/arm-smmu: Introduce wrapper for writeq/readq iommu/arm-smmu: Workaround for Marvell Armada-AP806 SoC erratum #582743 dt-bindings: iommu/arm,smmu: add compatible string for Marvell Documentation/arm64/silicon-errata.txt | 2 + .../devicetree/bindings/iommu/arm,smmu.txt | 1 + arch/arm64/boot/dts/marvell/armada-ap806.dtsi | 17 +++++ drivers/iommu/arm-smmu.c | 74 ++++++++++++++++--- 4 files changed, 83 insertions(+), 11 deletions(-) -- 2.20.1