| commit | 6c2ccb39b55f10094b7f7486baabbf81b664c4b5 | [log] [tgz] |
|---|---|---|
| author | Mike Voydanoff <voydanoff@google.com> | Wed Sep 19 07:10:04 2018 -0700 |
| committer | Mike Voydanoff <voydanoff@google.com> | Wed Sep 19 19:51:04 2018 +0000 |
| tree | 8c8d8a1f441f9989b21a7e8a61151b2926bfbe79 | |
| parent | ace6a9aef37b0cbef0da1072e6b2831f671af4b0 [diff] |
[gpio] Refactor the GPIO protocol This is a first step in a move toward using protocols to represent individual resources. A similar change will be made to the I2C protocol to bring it in line with how I2C is used on x86 platforms. From the client's point of view, an instance of the ZX_PROTOCOL_GPIO protocol now represents a single pin. The protocol remains the same, except the "uint32_t index" has been removed from all the protocol functions. For devices that have only one GPIO resource assigned to them, the driver can simply call device_get_protocol() to access the GPIO protocol for the pin. To for devices with more than one GPIO pins, a new API in the platform bus called pdev_get_protocol() must be used instead. In addition, we add a new protocol ZX_PROTOCOL_GPIO_IMPL, which is now implemented by the GPIO drivers. This protocol is essentially the same as the old GPIO protocol, except "index" has been renamed "pin". Board drivers may use this protocol directly when doing low level system configuration, specifying pin numbers directly. TEST: Booted on VIM2 and Hikey. On VIM2, USB, display, ethernet and the GPIO test driver are working properly On Hikey, the system boots and USB is functional. Change-Id: I44f1bc11ad9793543361a2d19d7a2de4458c334b
Zircon is the core platform that powers the Fuchsia OS. Zircon is composed of a microkernel (source in kernel/...) as well as a small set of userspace services, drivers, and libraries (source in system/...) necessary for the system to boot, talk to hardware, load userspace processes and run them, etc. Fuchsia builds a much larger OS on top of this foundation.
The canonical Zircon Git repository is located at: https://fuchsia.googlesource.com/zircon
A read-only mirror of the code is present at: https://github.com/fuchsia-mirror/zircon
The Zircon Kernel provides syscalls to manage processes, threads, virtual memory, inter-process communication, waiting on object state changes, and locking (via futexes).
Currently there are some temporary syscalls that have been used for early bringup work, which will be going away in the future as the long term syscall API/ABI surface is finalized. The expectation is that there will be about 100 syscalls.
Zircon syscalls are generally non-blocking. The wait_one, wait_many port_wait and thread sleep being the notable exceptions.
This page is a non-comprehensive index of the zircon documentation.