memory: Add NVIDIA Tegra memory controller support

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>

1 files changed, 25 insertions, 0 deletions

diff --git a/include/dt-bindings/memory/tegra114-mc.h b/include/dt-bindings/memory/tegra114-mc.h
new file mode 100644
index 000000000000..8f48985a3139
--- /dev/null
+++ b/include/dt-bindings/memory/tegra114-mc.h
@@ -0,0 +1,25 @@
+#ifndef DT_BINDINGS_MEMORY_TEGRA114_MC_H
+#define DT_BINDINGS_MEMORY_TEGRA114_MC_H
+
+#define TEGRA_SWGROUP_PTC	0
+#define TEGRA_SWGROUP_DC	1
+#define TEGRA_SWGROUP_DCB	2
+#define TEGRA_SWGROUP_EPP	3
+#define TEGRA_SWGROUP_G2	4
+#define TEGRA_SWGROUP_AVPC	5
+#define TEGRA_SWGROUP_NV	6
+#define TEGRA_SWGROUP_HDA	7
+#define TEGRA_SWGROUP_HC	8
+#define TEGRA_SWGROUP_MSENC	9
+#define TEGRA_SWGROUP_PPCS	10
+#define TEGRA_SWGROUP_VDE	11
+#define TEGRA_SWGROUP_MPCORELP	12
+#define TEGRA_SWGROUP_MPCORE	13
+#define TEGRA_SWGROUP_VI	14
+#define TEGRA_SWGROUP_ISP	15
+#define TEGRA_SWGROUP_XUSB_HOST	16
+#define TEGRA_SWGROUP_XUSB_DEV	17
+#define TEGRA_SWGROUP_EMUCIF	18
+#define TEGRA_SWGROUP_TSEC	19
+
+#endif