[PATCH 00/18] Clean up exposure of arch-internal code
joro at 8bytes.org
Mon Jul 27 06:13:13 PDT 2015
[+ Heiko for comment on Rockchip IOMMU]
On Mon, Jul 27, 2015 at 01:28:24PM +0100, Russell King - ARM Linux wrote:
> This series of patches attempts to clean up the use of architecture
> internal functions in drivers, and removes some functions from view
> in the asm/ headers. I'm also considering whether we need to add
> some linker magic to hide symbols when building the built-in.o files.
> This was triggered by 3rd party drivers "going under the covers" of
> the DMA API and calling the dmac_*() functions directly, a practice
> which I have always refused to allow. This also breaks module
> building (which is the big hint that they're doing something wrong.)
> However, it also came to light that various drivers are using
> __cpuc_* functions directly, which are non-portable, and is another
> instance of "going under the covers" and tinkering with what should
> be kept as architecture implementation details.
> This series addresses some of these points. It:
> (a) moves dmac_map_area() and dmac_unmap_area() prototypes out of
> asm/cacheflush.h and into arch/arm/mm.
> (b) provide a secure_flush() call for the Qualcomm secure monitor
> (c) stop tegra smmu driver(s) from using __cpuc_flush_dcache_area,
> something which necessitates additional complexity to deal with
> the ARM vs ARM64 differences. It should be using the DMA API.
> However, the Tegra SMMU driver is in really bad shape, and this
> isn't a simple conversion - it requires a lot of additional
> fixes to bring the code up to scratch.
> It leaves the Rockchip IOMMU driver for the time being, but that is also
> something which needs cleaning up in the same way as the Tegra SMMU
> arch/arm/include/asm/cacheflush.h | 21 ++-
> arch/arm/include/asm/glue-cache.h | 2 -
> arch/arm/mm/dma-mapping.c | 1 +
> arch/arm/mm/dma.h | 32 ++++
> drivers/firmware/qcom_scm-32.c | 4 +-
> drivers/iommu/tegra-smmu.c | 297 ++++++++++++++++++++++++--------------
> drivers/memory/tegra/tegra114.c | 17 ---
> drivers/memory/tegra/tegra124.c | 30 ----
> drivers/memory/tegra/tegra30.c | 17 ---
> include/soc/tegra/mc.h | 7 -
> 10 files changed, 242 insertions(+), 186 deletions(-)
> FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
> according to speedtest.net.
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