diff options
Diffstat (limited to 'Documentation')
4 files changed, 81 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/arm/altera.txt b/Documentation/devicetree/bindings/arm/altera.txt new file mode 100644 index 000000000000..558735aacca8 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/altera.txt @@ -0,0 +1,14 @@ +Altera's SoCFPGA platform device tree bindings +--------------------------------------------- + +Boards with Cyclone 5 SoC: +Required root node properties: +compatible = "altr,socfpga-cyclone5", "altr,socfpga"; + +Boards with Arria 5 SoC: +Required root node properties: +compatible = "altr,socfpga-arria5", "altr,socfpga"; + +Boards with Arria 10 SoC: +Required root node properties: +compatible = "altr,socfpga-arria10", "altr,socfpga"; diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt index 256b4d8bab7b..e774128935d5 100644 --- a/Documentation/devicetree/bindings/arm/arch_timer.txt +++ b/Documentation/devicetree/bindings/arm/arch_timer.txt @@ -17,7 +17,10 @@ to deliver its interrupts via SPIs. - interrupts : Interrupt list for secure, non-secure, virtual and hypervisor timers, in that order. -- clock-frequency : The frequency of the main counter, in Hz. Optional. +- clock-frequency : The frequency of the main counter, in Hz. Should be present + only where necessary to work around broken firmware which does not configure + CNTFRQ on all CPUs to a uniform correct value. Use of this property is + strongly discouraged; fix your firmware unless absolutely impossible. - always-on : a boolean property. If present, the timer is powered through an always-on power domain, therefore it never loses context. @@ -46,7 +49,8 @@ Example: - compatible : Should at least contain "arm,armv7-timer-mem". -- clock-frequency : The frequency of the main counter, in Hz. Optional. +- clock-frequency : The frequency of the main counter, in Hz. Should be present + only when firmware has not configured the MMIO CNTFRQ registers. - reg : The control frame base address. diff --git a/Documentation/devicetree/bindings/common-properties.txt b/Documentation/devicetree/bindings/common-properties.txt new file mode 100644 index 000000000000..3193979b1d05 --- /dev/null +++ b/Documentation/devicetree/bindings/common-properties.txt @@ -0,0 +1,60 @@ +Common properties + +The ePAPR specification does not define any properties related to hardware +byteswapping, but endianness issues show up frequently in porting Linux to +different machine types. This document attempts to provide a consistent +way of handling byteswapping across drivers. + +Optional properties: + - big-endian: Boolean; force big endian register accesses + unconditionally (e.g. ioread32be/iowrite32be). Use this if you + know the peripheral always needs to be accessed in BE mode. + - little-endian: Boolean; force little endian register accesses + unconditionally (e.g. readl/writel). Use this if you know the + peripheral always needs to be accessed in LE mode. + - native-endian: Boolean; always use register accesses matched to the + endianness of the kernel binary (e.g. LE vmlinux -> readl/writel, + BE vmlinux -> ioread32be/iowrite32be). In this case no byteswaps + will ever be performed. Use this if the hardware "self-adjusts" + register endianness based on the CPU's configured endianness. + +If a binding supports these properties, then the binding should also +specify the default behavior if none of these properties are present. +In such cases, little-endian is the preferred default, but it is not +a requirement. The of_device_is_big_endian() and of_fdt_is_big_endian() +helper functions do assume that little-endian is the default, because +most existing (PCI-based) drivers implicitly default to LE by using +readl/writel for MMIO accesses. + +Examples: +Scenario 1 : CPU in LE mode & device in LE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + native-endian; +}; + +Scenario 2 : CPU in LE mode & device in BE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + big-endian; +}; + +Scenario 3 : CPU in BE mode & device in BE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + native-endian; +}; + +Scenario 4 : CPU in BE mode & device in LE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + little-endian; +}; diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt index 83737a3403d7..80339192c93e 100644 --- a/Documentation/devicetree/bindings/vendor-prefixes.txt +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt @@ -26,6 +26,7 @@ aptina Aptina Imaging arasan Arasan Chip Systems arm ARM Ltd. armadeus ARMadeus Systems SARL +artesyn Artesyn Embedded Technologies Inc. asahi-kasei Asahi Kasei Corp. atmel Atmel Corporation auo AU Optronics Corporation |