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Signed-off-by: Simon Glass --- Changes in v4: - New patch .../schemas/reserved-memory/framebuffer.yaml | 52 +++++++ .../reserved-memory/google,open-dice.yaml | 46 ++++++ .../reserved-memory/memory-region.yaml | 40 +++++ .../nvidia,tegra210-emc-table.yaml | 31 ++++ .../nvidia,tegra264-bpmp-shmem.yaml | 47 ++++++ dtschema/schemas/reserved-memory/phram.yaml | 47 ++++++ .../schemas/reserved-memory/qcom,cmd-db.yaml | 46 ++++++ .../reserved-memory/qcom,rmtfs-mem.yaml | 55 +++++++ dtschema/schemas/reserved-memory/ramoops.yaml | 144 ++++++++++++++++++ .../reserved-memory/shared-dma-pool.yaml | 97 ++++++++++++ 10 files changed, 605 insertions(+) create mode 100644 dtschema/schemas/reserved-memory/framebuffer.yaml create mode 100644 dtschema/schemas/reserved-memory/google,open-dice.yaml create mode 100644 dtschema/schemas/reserved-memory/memory-region.yaml create mode 100644 dtschema/schemas/reserved-memory/nvidia,tegra210-emc-table.yaml create mode 100644 dtschema/schemas/reserved-memory/nvidia,tegra264-bpmp-shmem.yaml create mode 100644 dtschema/schemas/reserved-memory/phram.yaml create mode 100644 dtschema/schemas/reserved-memory/qcom,cmd-db.yaml create mode 100644 dtschema/schemas/reserved-memory/qcom,rmtfs-mem.yaml create mode 100644 dtschema/schemas/reserved-memory/ramoops.yaml create mode 100644 dtschema/schemas/reserved-memory/shared-dma-pool.yaml diff --git a/dtschema/schemas/reserved-memory/framebuffer.yaml b/dtschema/schemas/reserved-memory/framebuffer.yaml new file mode 100644 index 0000000..851ec24 --- /dev/null +++ b/dtschema/schemas/reserved-memory/framebuffer.yaml @@ -0,0 +1,52 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/framebuffer.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: /reserved-memory framebuffer node + +maintainers: + - devicetree-spec@vger.kernel.org + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + const: framebuffer + description: > + This indicates a region of memory meant to be used as a framebuffer for + a set of display devices. It can be used by an operating system to keep + the framebuffer from being overwritten and use it as the backing memory + for a display device (such as simple-framebuffer). + +unevaluatedProperties: false + +examples: + - | + / { + compatible = "foo"; + model = "foo"; + #address-cells = <1>; + #size-cells = <1>; + + chosen { + framebuffer { + compatible = "simple-framebuffer"; + memory-region = <&fb>; + }; + }; + + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + ranges; + + fb: framebuffer@80000000 { + compatible = "framebuffer"; + reg = <0x80000000 0x007e9000>; + }; + }; + }; +... diff --git a/dtschema/schemas/reserved-memory/google,open-dice.yaml b/dtschema/schemas/reserved-memory/google,open-dice.yaml new file mode 100644 index 0000000..c591ec3 --- /dev/null +++ b/dtschema/schemas/reserved-memory/google,open-dice.yaml @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/google,open-dice.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Open Profile for DICE + +description: | + This binding represents a reserved memory region containing data + generated by the Open Profile for DICE protocol. + + See https://pigweed.googlesource.com/open-dice/ + +maintainers: + - David Brazdil + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + const: google,open-dice + + reg: + description: page-aligned region of memory containing DICE data + +required: + - compatible + - reg + - no-map + +unevaluatedProperties: false + +examples: + - | + reserved-memory { + #address-cells = <2>; + #size-cells = <1>; + + dice: dice@12340000 { + compatible = "google,open-dice"; + reg = <0x00 0x12340000 0x2000>; + no-map; + }; + }; diff --git a/dtschema/schemas/reserved-memory/memory-region.yaml b/dtschema/schemas/reserved-memory/memory-region.yaml new file mode 100644 index 0000000..592f180 --- /dev/null +++ b/dtschema/schemas/reserved-memory/memory-region.yaml @@ -0,0 +1,40 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/memory-region.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Reserved Memory Region + +maintainers: + - devicetree-spec@vger.kernel.org + +description: | + Regions in the /reserved-memory node may be referenced by other device + nodes by adding a memory-region property to the device node. + +select: true + +properties: + memory-region: + $ref: /schemas/types.yaml#/definitions/phandle-array + description: > + Phandle to a /reserved-memory child node assigned to the device. + + memory-region-names: + $ref: /schemas/types.yaml#/definitions/string-array + description: > + A list of names, one for each corresponding entry in the + memory-region property + +additionalProperties: true + +examples: + - | + fb0: video@12300000 { + /* ... */ + reg = <0x12300000 0x1000>; + memory-region = <&display_reserved>; + }; + +... diff --git a/dtschema/schemas/reserved-memory/nvidia,tegra210-emc-table.yaml b/dtschema/schemas/reserved-memory/nvidia,tegra210-emc-table.yaml new file mode 100644 index 0000000..e2ace3d --- /dev/null +++ b/dtschema/schemas/reserved-memory/nvidia,tegra210-emc-table.yaml @@ -0,0 +1,31 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/nvidia,tegra210-emc-table.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: NVIDIA Tegra210 EMC Frequency Table + +maintainers: + - Thierry Reding + - Jon Hunter + +description: On Tegra210, firmware passes a binary representation of the + EMC frequency table via a reserved memory region. + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + const: nvidia,tegra210-emc-table + + reg: + description: region of memory reserved by firmware to pass the EMC + frequency table + +unevaluatedProperties: false + +required: + - compatible + - reg diff --git a/dtschema/schemas/reserved-memory/nvidia,tegra264-bpmp-shmem.yaml b/dtschema/schemas/reserved-memory/nvidia,tegra264-bpmp-shmem.yaml new file mode 100644 index 0000000..f9b2f0f --- /dev/null +++ b/dtschema/schemas/reserved-memory/nvidia,tegra264-bpmp-shmem.yaml @@ -0,0 +1,47 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/nvidia,tegra264-bpmp-shmem.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Tegra CPU-NS - BPMP IPC reserved memory + +maintainers: + - Peter De Schrijver + +description: | + Define a memory region used for communication between CPU-NS and BPMP. + Typically this node is created by the bootloader as the physical address + has to be known to both CPU-NS and BPMP for correct IPC operation. + The memory region is defined using a child node under /reserved-memory. + The sub-node is named shmem@
. + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + const: nvidia,tegra264-bpmp-shmem + + reg: + description: The physical address and size of the shared SDRAM region + +unevaluatedProperties: false + +required: + - compatible + - reg + - no-map + +examples: + - | + reserved-memory { + #address-cells = <2>; + #size-cells = <2>; + dram_cpu_bpmp_mail: shmem@f1be0000 { + compatible = "nvidia,tegra264-bpmp-shmem"; + reg = <0x0 0xf1be0000 0x0 0x2000>; + no-map; + }; + }; +... diff --git a/dtschema/schemas/reserved-memory/phram.yaml b/dtschema/schemas/reserved-memory/phram.yaml new file mode 100644 index 0000000..65c7cac --- /dev/null +++ b/dtschema/schemas/reserved-memory/phram.yaml @@ -0,0 +1,47 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/phram.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: MTD/block device in RAM + +description: | + Specifies that the reserved memory region can be used as an MTD or block + device. + + The "phram" node is named after the "MTD in PHysical RAM" driver which + provides an implementation of this functionality in Linux. + +maintainers: + - Vincent Whitchurch + +allOf: + - $ref: reserved-memory.yaml + - $ref: /schemas/mtd/mtd.yaml + +properties: + compatible: + const: phram + + reg: + description: region of memory that can be used as an MTD/block device + +required: + - compatible + - reg + +unevaluatedProperties: false + +examples: + - | + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + + phram: flash@12340000 { + compatible = "phram"; + label = "rootfs"; + reg = <0x12340000 0x00800000>; + }; + }; diff --git a/dtschema/schemas/reserved-memory/qcom,cmd-db.yaml b/dtschema/schemas/reserved-memory/qcom,cmd-db.yaml new file mode 100644 index 0000000..610f8ef --- /dev/null +++ b/dtschema/schemas/reserved-memory/qcom,cmd-db.yaml @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/qcom,cmd-db.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Qualcomm Command DB + +description: | + 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. + +maintainers: + - Bjorn Andersson + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + const: qcom,cmd-db + +required: + - reg + +unevaluatedProperties: false + +examples: + - | + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + ranges; + + reserved-memory@85fe0000 { + reg = <0x85fe0000 0x20000>; + compatible = "qcom,cmd-db"; + no-map; + }; + }; diff --git a/dtschema/schemas/reserved-memory/qcom,rmtfs-mem.yaml b/dtschema/schemas/reserved-memory/qcom,rmtfs-mem.yaml new file mode 100644 index 0000000..bab982f --- /dev/null +++ b/dtschema/schemas/reserved-memory/qcom,rmtfs-mem.yaml @@ -0,0 +1,55 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/qcom,rmtfs-mem.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Qualcomm Remote File System Memory + +description: | + 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. + +maintainers: + - Bjorn Andersson + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + const: qcom,rmtfs-mem + + qcom,client-id: + $ref: /schemas/types.yaml#/definitions/uint32 + description: > + identifier of the client to use this region for buffers + + qcom,vmid: + $ref: /schemas/types.yaml#/definitions/uint32-array + description: > + Array of vmids of the remote processors, to set up memory protection + minItems: 1 + maxItems: 2 + +required: + - qcom,client-id + +unevaluatedProperties: false + +examples: + - | + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + ranges; + + rmtfs@86700000 { + compatible = "qcom,rmtfs-mem"; + reg = <0x86700000 0xe0000>; + no-map; + + qcom,client-id = <1>; + }; + }; diff --git a/dtschema/schemas/reserved-memory/ramoops.yaml b/dtschema/schemas/reserved-memory/ramoops.yaml new file mode 100644 index 0000000..45cc39e --- /dev/null +++ b/dtschema/schemas/reserved-memory/ramoops.yaml @@ -0,0 +1,144 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/ramoops.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Ramoops oops/panic logger + +description: | + 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. + +maintainers: + - Kees Cook + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + const: ramoops + + reg: + description: region of memory that is preserved between reboots + + ecc-size: + $ref: /schemas/types.yaml#/definitions/uint32 + description: enables ECC support and specifies ECC buffer size in bytes + default: 0 # no ECC + + record-size: + $ref: /schemas/types.yaml#/definitions/uint32 + description: maximum size in bytes of each kmsg dump + default: 0 + + console-size: + $ref: /schemas/types.yaml#/definitions/uint32 + description: size in bytes of log buffer reserved for kernel messages + default: 0 + + ftrace-size: + $ref: /schemas/types.yaml#/definitions/uint32 + description: size in bytes of log buffer reserved for function tracing and profiling + default: 0 + + pmsg-size: + $ref: /schemas/types.yaml#/definitions/uint32 + description: size in bytes of log buffer reserved for userspace messages + default: 0 + + mem-type: + $ref: /schemas/types.yaml#/definitions/uint32 + description: if present, sets the type of mapping is to be used to map the reserved region. + default: 0 + oneOf: + - const: 0 + description: write-combined + - const: 1 + description: unbuffered + - const: 2 + description: cached + + max-reason: + $ref: /schemas/types.yaml#/definitions/uint32 + default: 2 # log oopses and panics + maximum: 0x7fffffff + description: | + If present, sets maximum type of kmsg dump reasons to store. + 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 2 (KMSG_DUMP_OOPS), otherwise 5 (KMSG_DUMP_MAX). + + flags: + $ref: /schemas/types.yaml#/definitions/uint32 + default: 0 + description: | + If present, pass ramoops behavioral flags + (see include/linux/pstore_ram.h RAMOOPS_FLAG_* for flag values). + + no-dump-oops: + deprecated: true + type: boolean + description: | + Use max_reason instead. If present, and max_reason is not specified, + it is equivalent to max_reason = 1 (KMSG_DUMP_PANIC). + + unbuffered: + deprecated: true + type: boolean + description: | + Use mem_type instead. If present, and mem_type is not specified, + it is equivalent to mem_type = 1 and uses unbuffered mappings to map + the reserved region (defaults to buffered mappings mem_type = 0). + If both are specified -- "mem_type" overrides "unbuffered". + +unevaluatedProperties: false + +required: + - compatible + - reg + +anyOf: + - required: [record-size] + - required: [console-size] + - required: [ftrace-size] + - required: [pmsg-size] + +examples: + - | + / { + compatible = "foo"; + model = "foo"; + #address-cells = <1>; + #size-cells = <1>; + + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + ranges; + + ramoops@bfdf0000 { + compatible = "ramoops"; + reg = <0xbfdf0000 0x10000>; /* 64kB */ + console-size = <0x8000>; /* 32kB */ + record-size = <0x400>; /* 1kB */ + ecc-size = <16>; + }; + }; + }; diff --git a/dtschema/schemas/reserved-memory/shared-dma-pool.yaml b/dtschema/schemas/reserved-memory/shared-dma-pool.yaml new file mode 100644 index 0000000..457de09 --- /dev/null +++ b/dtschema/schemas/reserved-memory/shared-dma-pool.yaml @@ -0,0 +1,97 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/shared-dma-pool.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: /reserved-memory DMA pool + +maintainers: + - devicetree-spec@vger.kernel.org + +allOf: + - $ref: reserved-memory.yaml + +properties: + compatible: + oneOf: + - const: shared-dma-pool + description: > + 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. + + - const: restricted-dma-pool + description: > + This indicates a region of memory meant to be used as a pool + of restricted DMA buffers for a set of devices. The memory + region would be the only region accessible to those devices. + When using this, the no-map and reusable properties must not + be set, so the operating system can create a virtual mapping + that will be used for synchronization. The main purpose for + restricted DMA is to mitigate the lack of DMA access control + on systems without an IOMMU, which could result in the DMA + accessing the system memory at unexpected times and/or + unexpected addresses, possibly leading to data leakage or + corruption. The feature on its own provides a basic level of + protection against the DMA overwriting buffer contents at + unexpected times. However, to protect against general data + leakage and system memory corruption, the system needs to + provide way to lock down the memory access, e.g., MPU. Note + that since coherent allocation needs remapping, one must set + up another device coherent pool by shared-dma-pool and use + dma_alloc_from_dev_coherent instead for atomic coherent + allocation. + + linux,cma-default: + type: boolean + description: > + If this property is present, then Linux will use the region for + the default pool of the contiguous memory allocator. + + linux,dma-default: + type: boolean + description: > + If this property is present, then Linux will use the region for + the default pool of the consistent DMA allocator. + +if: + properties: + compatible: + contains: + const: restricted-dma-pool +then: + properties: + no-map: false + reusable: false + +unevaluatedProperties: false + +examples: + - | + 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>; + }; + + restricted_dma_reserved: restricted-dma-pool@50000000 { + compatible = "restricted-dma-pool"; + reg = <0x50000000 0x4000000>; + }; + }; + +...