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-rw-r--r--Documentation/devicetree/bindings/reserved-memory/qcom,cmd-db.txt37
-rw-r--r--Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.txt51
-rw-r--r--Documentation/devicetree/bindings/reserved-memory/ramoops.txt60
-rw-r--r--Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt141
-rw-r--r--Documentation/devicetree/bindings/reserved-memory/xen,shared-memory.txt24
5 files changed, 313 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/reserved-memory/qcom,cmd-db.txt b/Documentation/devicetree/bindings/reserved-memory/qcom,cmd-db.txt
new file mode 100644
index 000000000..68395530c
--- /dev/null
+++ b/Documentation/devicetree/bindings/reserved-memory/qcom,cmd-db.txt
@@ -0,0 +1,37 @@
+Command DB
+---------
+
+Command DB is a database that provides a mapping between resource key and the
+resource address for a system resource managed by a remote processor. The data
+is stored in a shared memory region and is loaded by the remote processor.
+
+Some of the Qualcomm Technologies Inc SoC's have hardware accelerators for
+controlling shared resources. Depending on the board configuration the shared
+resource properties may change. These properties are dynamically probed by the
+remote processor and made available in the shared memory.
+
+The bindings for Command DB is specified in the reserved-memory section in
+devicetree. The devicetree representation of the command DB driver should be:
+
+Properties:
+- compatible:
+ Usage: required
+ Value type: <string>
+ Definition: Should be "qcom,cmd-db"
+
+- reg:
+ Usage: required
+ Value type: <prop encoded array>
+ Definition: The register address that points to the actual location of
+ the Command DB in memory.
+
+Example:
+
+ reserved-memory {
+ [...]
+ reserved-memory@85fe0000 {
+ reg = <0x0 0x85fe0000 0x0 0x20000>;
+ compatible = "qcom,cmd-db";
+ no-map;
+ };
+ };
diff --git a/Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.txt b/Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.txt
new file mode 100644
index 000000000..8562ba1dc
--- /dev/null
+++ b/Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.txt
@@ -0,0 +1,51 @@
+Qualcomm Remote File System Memory binding
+
+This binding describes the Qualcomm remote filesystem memory, which serves the
+purpose of describing the shared memory region used for remote processors to
+access block device data using the Remote Filesystem protocol.
+
+- compatible:
+ Usage: required
+ Value type: <stringlist>
+ Definition: must be:
+ "qcom,rmtfs-mem"
+
+- reg:
+ Usage: required for static allocation
+ Value type: <prop-encoded-array>
+ Definition: must specify base address and size of the memory region,
+ as described in reserved-memory.txt
+
+- size:
+ Usage: required for dynamic allocation
+ Value type: <prop-encoded-array>
+ Definition: must specify a size of the memory region, as described in
+ reserved-memory.txt
+
+- qcom,client-id:
+ Usage: required
+ Value type: <u32>
+ Definition: identifier of the client to use this region for buffers.
+
+- qcom,vmid:
+ Usage: optional
+ Value type: <u32>
+ Definition: vmid of the remote processor, to set up memory protection.
+
+= EXAMPLE
+The following example shows the remote filesystem memory setup for APQ8016,
+with the rmtfs region for the Hexagon DSP (id #1) located at 0x86700000.
+
+ reserved-memory {
+ #address-cells = <2>;
+ #size-cells = <2>;
+ ranges;
+
+ rmtfs@86700000 {
+ compatible = "qcom,rmtfs-mem";
+ reg = <0x0 0x86700000 0x0 0xe0000>;
+ no-map;
+
+ qcom,client-id = <1>;
+ };
+ };
diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt
new file mode 100644
index 000000000..b7886fea3
--- /dev/null
+++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt
@@ -0,0 +1,60 @@
+Ramoops oops/panic logger
+=========================
+
+ramoops provides persistent RAM storage for oops and panics, so they can be
+recovered after a reboot. This is a child-node of "/reserved-memory", and
+is named "ramoops" after the backend, rather than "pstore" which is the
+subsystem.
+
+Parts of this storage may be set aside for other persistent log buffers, such
+as kernel log messages, or for optional ECC error-correction data. The total
+size of these optional buffers must fit in the reserved region.
+
+Any remaining space will be used for a circular buffer of oops and panic
+records. These records have a configurable size, with a size of 0 indicating
+that they should be disabled.
+
+At least one of "record-size", "console-size", "ftrace-size", or "pmsg-size"
+must be set non-zero, but are otherwise optional as listed below.
+
+
+Required properties:
+
+- compatible: must be "ramoops"
+
+- reg: region of memory that is preserved between reboots
+
+
+Optional properties:
+
+- ecc-size: enables ECC support and specifies ECC buffer size in bytes
+ (defaults to 0: no ECC)
+
+- record-size: maximum size in bytes of each kmsg dump.
+ (defaults to 0: disabled)
+
+- console-size: size in bytes of log buffer reserved for kernel messages
+ (defaults to 0: disabled)
+
+- ftrace-size: size in bytes of log buffer reserved for function tracing and
+ profiling (defaults to 0: disabled)
+
+- pmsg-size: size in bytes of log buffer reserved for userspace messages
+ (defaults to 0: disabled)
+
+- unbuffered: if present, use unbuffered mappings to map the reserved region
+ (defaults to buffered mappings)
+
+- max-reason: if present, sets maximum type of kmsg dump reasons to store
+ (defaults to 2: log Oopses and Panics). This can be set to INT_MAX to
+ store all kmsg dumps. See include/linux/kmsg_dump.h KMSG_DUMP_* for other
+ kmsg dump reason values. Setting this to 0 (KMSG_DUMP_UNDEF), means the
+ reason filtering will be controlled by the printk.always_kmsg_dump boot
+ param: if unset, it will be KMSG_DUMP_OOPS, otherwise KMSG_DUMP_MAX.
+
+- no-dump-oops: deprecated, use max_reason instead. If present, and
+ max_reason is not specified, it is equivalent to max_reason = 1
+ (KMSG_DUMP_PANIC).
+
+- flags: if present, pass ramoops behavioral flags (defaults to 0,
+ see include/linux/pstore_ram.h RAMOOPS_FLAG_* for flag values).
diff --git a/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
new file mode 100644
index 000000000..e8d3096d9
--- /dev/null
+++ b/Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
@@ -0,0 +1,141 @@
+*** Reserved memory regions ***
+
+Reserved memory is specified as a node under the /reserved-memory node.
+The operating system shall exclude reserved memory from normal usage
+one can create child nodes describing particular reserved (excluded from
+normal use) memory regions. Such memory regions are usually designed for
+the special usage by various device drivers.
+
+Parameters for each memory region can be encoded into the device tree
+with the following nodes:
+
+/reserved-memory node
+---------------------
+#address-cells, #size-cells (required) - standard definition
+ - Should use the same values as the root node
+ranges (required) - standard definition
+ - Should be empty
+
+/reserved-memory/ child nodes
+-----------------------------
+Each child of the reserved-memory node specifies one or more regions of
+reserved memory. Each child node may either use a 'reg' property to
+specify a specific range of reserved memory, or a 'size' property with
+optional constraints to request a dynamically allocated block of memory.
+
+Following the generic-names recommended practice, node names should
+reflect the purpose of the node (ie. "framebuffer" or "dma-pool"). Unit
+address (@<address>) should be appended to the name if the node is a
+static allocation.
+
+Properties:
+Requires either a) or b) below.
+a) static allocation
+ reg (required) - standard definition
+b) dynamic allocation
+ size (required) - length based on parent's #size-cells
+ - Size in bytes of memory to reserve.
+ alignment (optional) - length based on parent's #size-cells
+ - Address boundary for alignment of allocation.
+ alloc-ranges (optional) - prop-encoded-array (address, length pairs).
+ - Specifies regions of memory that are
+ acceptable to allocate from.
+
+If both reg and size are present, then the reg property takes precedence
+and size is ignored.
+
+Additional properties:
+compatible (optional) - standard definition
+ - may contain the following strings:
+ - shared-dma-pool: This indicates a region of memory meant to be
+ used as a shared pool of DMA buffers for a set of devices. It can
+ be used by an operating system to instantiate the necessary pool
+ management subsystem if necessary.
+ - vendor specific string in the form <vendor>,[<device>-]<usage>
+no-map (optional) - empty property
+ - Indicates the operating system must not create a virtual mapping
+ of the region as part of its standard mapping of system memory,
+ nor permit speculative access to it under any circumstances other
+ than under the control of the device driver using the region.
+reusable (optional) - empty property
+ - The operating system can use the memory in this region with the
+ limitation that the device driver(s) owning the region need to be
+ able to reclaim it back. Typically that means that the operating
+ system can use that region to store volatile or cached data that
+ can be otherwise regenerated or migrated elsewhere.
+
+A node must not carry both the no-map and the reusable property as these are
+logically contradictory.
+
+Linux implementation note:
+- If a "linux,cma-default" property is present, then Linux will use the
+ region for the default pool of the contiguous memory allocator.
+
+- If a "linux,dma-default" property is present, then Linux will use the
+ region for the default pool of the consistent DMA allocator.
+
+Device node references to reserved memory
+-----------------------------------------
+Regions in the /reserved-memory node may be referenced by other device
+nodes by adding a memory-region property to the device node.
+
+memory-region (optional) - phandle, specifier pairs to children of /reserved-memory
+memory-region-names (optional) - a list of names, one for each corresponding
+ entry in the memory-region property
+
+Example
+-------
+This example defines 3 contiguous regions are defined for Linux kernel:
+one default of all device drivers (named linux,cma@72000000 and 64MiB in size),
+one dedicated to the framebuffer device (named framebuffer@78000000, 8MiB), and
+one for multimedia processing (named multimedia-memory@77000000, 64MiB).
+
+/ {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ memory {
+ reg = <0x40000000 0x40000000>;
+ };
+
+ reserved-memory {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ /* global autoconfigured region for contiguous allocations */
+ linux,cma {
+ compatible = "shared-dma-pool";
+ reusable;
+ size = <0x4000000>;
+ alignment = <0x2000>;
+ linux,cma-default;
+ };
+
+ display_reserved: framebuffer@78000000 {
+ reg = <0x78000000 0x800000>;
+ };
+
+ multimedia_reserved: multimedia@77000000 {
+ compatible = "acme,multimedia-memory";
+ reg = <0x77000000 0x4000000>;
+ };
+ };
+
+ /* ... */
+
+ fb0: video@12300000 {
+ memory-region = <&display_reserved>;
+ /* ... */
+ };
+
+ scaler: scaler@12500000 {
+ memory-region = <&multimedia_reserved>;
+ /* ... */
+ };
+
+ codec: codec@12600000 {
+ memory-region = <&multimedia_reserved>;
+ /* ... */
+ };
+};
diff --git a/Documentation/devicetree/bindings/reserved-memory/xen,shared-memory.txt b/Documentation/devicetree/bindings/reserved-memory/xen,shared-memory.txt
new file mode 100644
index 000000000..d483a2103
--- /dev/null
+++ b/Documentation/devicetree/bindings/reserved-memory/xen,shared-memory.txt
@@ -0,0 +1,24 @@
+* Xen hypervisor reserved-memory binding
+
+Expose one or more memory regions as reserved-memory to the guest
+virtual machine. Typically, a region is configured at VM creation time
+to be a shared memory area across multiple virtual machines for
+communication among them.
+
+For each of these pre-shared memory regions, a range is exposed under
+the /reserved-memory node as a child node. Each range sub-node is named
+xen-shmem@<address> and has the following properties:
+
+- compatible:
+ compatible = "xen,shared-memory-v1"
+
+- reg:
+ the base guest physical address and size of the shared memory region
+
+- xen,offset: (borrower VMs only)
+ 64 bit integer offset within the owner virtual machine's shared
+ memory region used for the mapping in the borrower VM.
+
+- xen,id:
+ a string that identifies the shared memory region as specified in
+ the VM config file