]> www.infradead.org Git - users/jedix/linux-maple.git/commit
iommu/tegra-smmu: Parameterize number of TLB lines
authorThierry Reding <treding@nvidia.com>
Thu, 6 Aug 2015 12:20:31 +0000 (14:20 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 29 Sep 2015 17:26:14 +0000 (19:26 +0200)
commit1f398b31044845397b5e2fefdb7ac247180e6a7c
tree994359543f48ebee8d0fc61719c980b785641759
parentfb2908b509749657cab5f7dbda2f24add8668969
iommu/tegra-smmu: Parameterize number of TLB lines

commit 11cec15bf3fb498206ef63b1fa26c27689e02d0e upstream.

The number of TLB lines was increased from 16 on Tegra30 to 32 on
Tegra114 and later. Parameterize the value so that the initial default
can be set accordingly.

On Tegra30, initializing the value to 32 would effectively disable the
TLB and hence cause massive latencies for memory accesses translated
through the SMMU. This is especially noticeable for isochronuous clients
such as display, whose FIFOs would continuously underrun.

Fixes: 891846516317 ("memory: Add NVIDIA Tegra memory controller support")
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/iommu/tegra-smmu.c
drivers/memory/tegra/tegra114.c
drivers/memory/tegra/tegra124.c
drivers/memory/tegra/tegra30.c
include/soc/tegra/mc.h