| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into next/drivers
Merge "ARM: tegra: Add EMC driver for v4.2-rc1" from Thierry Reding:
This introduces the EMC driver that's required to scale the external
memory frequency.
* tag 'tegra-for-4.2-emc' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
memory: tegra: Add EMC frequency debugfs entry
memory: tegra: Add EMC (external memory controller) driver
memory: tegra: Add API needed by the EMC driver
of: Add Tegra124 EMC bindings
of: Document timings subnode of nvidia,tegra-mc
|
|
The EMC driver needs to know the number of external memory devices and
also needs to update the EMEM configuration based on the new rate of the
memory bus.
To know how to update the EMEM config, looks up the values of the burst
regs in the DT, for a given timing.
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
|
|
Provide clients and swgroups files in debugfs. These files show for
which clients IOMMU translation is enabled and which ASID is associated
with each SWGROUP.
Cc: Hiroshi Doyu <hdoyu@nvidia.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
|
|
Subsequent patches will add debugfs files that print the status of the
SWGROUPs. Add a new names field and complement the SoC tables with the
names of the individual SWGROUPs.
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>
|
