diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/arm/arm-boards | 2 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/arm/fw-cfg.txt | 72 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/graph.txt | 2 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/vendor-prefixes.txt | 4 |
4 files changed, 77 insertions, 3 deletions
diff --git a/Documentation/devicetree/bindings/arm/arm-boards b/Documentation/devicetree/bindings/arm/arm-boards index 556c8665fdbf..b78564b2b201 100644 --- a/Documentation/devicetree/bindings/arm/arm-boards +++ b/Documentation/devicetree/bindings/arm/arm-boards @@ -23,7 +23,7 @@ Required nodes: range of 0x200 bytes. - syscon: the root node of the Integrator platforms must have a - system controller node pointong to the control registers, + system controller node pointing to the control registers, with the compatible string "arm,integrator-ap-syscon" "arm,integrator-cp-syscon" diff --git a/Documentation/devicetree/bindings/arm/fw-cfg.txt b/Documentation/devicetree/bindings/arm/fw-cfg.txt new file mode 100644 index 000000000000..953fb640d9c4 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/fw-cfg.txt @@ -0,0 +1,72 @@ +* QEMU Firmware Configuration bindings for ARM + +QEMU's arm-softmmu and aarch64-softmmu emulation / virtualization targets +provide the following Firmware Configuration interface on the "virt" machine +type: + +- A write-only, 16-bit wide selector (or control) register, +- a read-write, 64-bit wide data register. + +QEMU exposes the control and data register to ARM guests as memory mapped +registers; their location is communicated to the guest's UEFI firmware in the +DTB that QEMU places at the bottom of the guest's DRAM. + +The guest writes a selector value (a key) to the selector register, and then +can read the corresponding data (produced by QEMU) via the data register. If +the selected entry is writable, the guest can rewrite it through the data +register. + +The selector register takes keys in big endian byte order. + +The data register allows accesses with 8, 16, 32 and 64-bit width (only at +offset 0 of the register). Accesses larger than a byte are interpreted as +arrays, bundled together only for better performance. The bytes constituting +such a word, in increasing address order, correspond to the bytes that would +have been transferred by byte-wide accesses in chronological order. + +The interface allows guest firmware to download various parameters and blobs +that affect how the firmware works and what tables it installs for the guest +OS. For example, boot order of devices, ACPI tables, SMBIOS tables, kernel and +initrd images for direct kernel booting, virtual machine UUID, SMP information, +virtual NUMA topology, and so on. + +The authoritative registry of the valid selector values and their meanings is +the QEMU source code; the structure of the data blobs corresponding to the +individual key values is also defined in the QEMU source code. + +The presence of the registers can be verified by selecting the "signature" blob +with key 0x0000, and reading four bytes from the data register. The returned +signature is "QEMU". + +The outermost protocol (involving the write / read sequences of the control and +data registers) is expected to be versioned, and/or described by feature bits. +The interface revision / feature bitmap can be retrieved with key 0x0001. The +blob to be read from the data register has size 4, and it is to be interpreted +as a uint32_t value in little endian byte order. The current value +(corresponding to the above outer protocol) is zero. + +The guest kernel is not expected to use these registers (although it is +certainly allowed to); the device tree bindings are documented here because +this is where device tree bindings reside in general. + +Required properties: + +- compatible: "qemu,fw-cfg-mmio". + +- reg: the MMIO region used by the device. + * Bytes 0x0 to 0x7 cover the data register. + * Bytes 0x8 to 0x9 cover the selector register. + * Further registers may be appended to the region in case of future interface + revisions / feature bits. + +Example: + +/ { + #size-cells = <0x2>; + #address-cells = <0x2>; + + fw-cfg@9020000 { + compatible = "qemu,fw-cfg-mmio"; + reg = <0x0 0x9020000 0x0 0xa>; + }; +}; diff --git a/Documentation/devicetree/bindings/graph.txt b/Documentation/devicetree/bindings/graph.txt index 1a69c078adf2..fcb1c6a4787b 100644 --- a/Documentation/devicetree/bindings/graph.txt +++ b/Documentation/devicetree/bindings/graph.txt @@ -19,7 +19,7 @@ type of the connections, they just map their existence. Specific properties may be described by specialized bindings depending on the type of connection. To see how this binding applies to video pipelines, for example, see -Documentation/device-tree/bindings/media/video-interfaces.txt. +Documentation/devicetree/bindings/media/video-interfaces.txt. Here the ports describe data interfaces, and the links between them are the connecting data buses. A single port with multiple connections can correspond to multiple devices being connected to the same physical bus. diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt index b1df0ad1306c..d443279c95dc 100644 --- a/Documentation/devicetree/bindings/vendor-prefixes.txt +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt @@ -9,7 +9,6 @@ ad Avionic Design GmbH adapteva Adapteva, Inc. adi Analog Devices, Inc. aeroflexgaisler Aeroflex Gaisler AB -ak Asahi Kasei Corp. allwinner Allwinner Technology Co., Ltd. altr Altera Corp. amcc Applied Micro Circuits Corporation (APM, formally AMCC) @@ -20,6 +19,7 @@ amstaos AMS-Taos Inc. apm Applied Micro Circuits Corporation (APM) arm ARM Ltd. armadeus ARMadeus Systems SARL +asahi-kasei Asahi Kasei Corp. atmel Atmel Corporation auo AU Optronics Corporation avago Avago Technologies @@ -127,6 +127,7 @@ pixcir PIXCIR MICROELECTRONICS Co., Ltd powervr PowerVR (deprecated, use img) qca Qualcomm Atheros, Inc. qcom Qualcomm Technologies, Inc +qemu QEMU, a generic and open source machine emulator and virtualizer qnap QNAP Systems, Inc. radxa Radxa raidsonic RaidSonic Technology GmbH @@ -168,6 +169,7 @@ usi Universal Scientific Industrial Co., Ltd. v3 V3 Semiconductor variscite Variscite Ltd. via VIA Technologies, Inc. +virtio Virtual I/O Device Specification, developed by the OASIS consortium voipac Voipac Technologies s.r.o. winbond Winbond Electronics corp. wlf Wolfson Microelectronics |