In order to reset busy HW properly, memory controller needs to be
involved, otherwise it is possible to get corrupted memory or hang machine
if HW was reset during DMA. Introduce memory client 'hot reset' that will
be used for resetting of busy HW.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tegra30+ has some minor differences in registers / bits layout compared
to Tegra20. Let's squash Tegra20 driver into the common tegra-mc driver
in a preparation for the upcoming MC hot reset controls implementation,
avoiding code duplication.
Note that this currently doesn't report the value of MC_GART_ERROR_REQ
because it is located within the GART register area and cannot be safely
accessed from the MC driver (this happens to work only by accident). The
proper solution is to integrate the GART driver with the MC driver, much
like is done for the Tegra SMMU, but that is an invasive change and will
be part of a separate patch series.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Currently we are enabling handling of interrupts specific to Tegra124+
which happen to overlap with previous generations. Let's specify
interrupts mask per SoC generation for consistency and in a preparation
of squashing of Tegra20 driver into the common one that will enable
handling of GART faults which may be undesirable by newer generations.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The memory controller on Tegra132 is very similar to the one found on
Tegra124. But the Denver CPUs don't have an outer cache, so dcache
maintenance is done slightly differently.
Signed-off-by: Thierry Reding <treding@nvidia.com>
The memory controller on NVIDIA Tegra exposes various knobs that can be
used to tune the behaviour of the clients attached to it.
Currently this driver sets up the latency allowance registers to the HW
defaults. Eventually an API should be exported by this driver (via a
custom API or a generic subsystem) to allow clients to register latency
requirements.
This driver also registers an IOMMU (SMMU) that's implemented by the
memory controller. It is supported on Tegra30, Tegra114 and Tegra124
currently. Tegra20 has a GART instead.
The Tegra SMMU operates on memory clients and SWGROUPs. A memory client
is a unidirectional, special-purpose DMA master. A SWGROUP represents a
set of memory clients that form a logical functional unit corresponding
to a single device. Typically a device has two clients: one client for
read transactions and one client for write transactions, but there are
also devices that have only read clients, but many of them (such as the
display controllers).
Because there is no 1:1 relationship between memory clients and devices
the driver keeps a table of memory clients and the SWGROUPs that they
belong to per SoC. Note that this is an exception and due to the fact
that the SMMU is tightly integrated with the rest of the Tegra SoC. The
use of these tables is discouraged in drivers for generic IOMMU devices
such as the ARM SMMU because the same IOMMU could be used in any number
of SoCs and keeping such tables for each SoC would not scale.
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Dmitry Osipenko