This ROCm Runtime (ROCr) repo combines 2 previously separate repos into a single repo:
- The HSA Runtime (`hsa-runtime`) for AMD GPU application development and
- The ROCt Thunk Library (`libhsakmt`), a "thunk" interface to the ROCm kernel driver (ROCk), used by the runtime.
## Infrastructure
The HSA runtime is a thin, user-mode API that exposes the necessary interfaces to access and interact with graphics hardware driven by the AMDGPU driver set and the ROCK kernel driver. Together they enable programmers to directly harness the power of AMD discrete graphics devices by allowing host applications to launch compute kernels directly to the graphics hardware.
The capabilities expressed by the HSA Runtime API are:
* Error handling
* Runtime initialization and shutdown
* System and agent information
* Signals and synchronization
* Architected dispatch
* Memory management
* HSA runtime fits into a typical software architecture stack.
The HSA runtime provides direct access to the graphics hardware to give the programmer more control of the execution. An example of low level hardware access is the support of one or more user mode queues provides programmers with a low-latency kernel dispatch interface, allowing them to develop customized dispatch algorithms specific to their application.
The HSA Architected Queuing Language is an open standard, defined by the HSA Foundation, specifying the packet syntax used to control supported AMD/ATI Radeon (c) graphics devices. The AQL language supports several packet types, including packets that can command the hardware to automatically resolve inter-packet dependencies (barrier AND & barrier OR packet), kernel dispatch packets and agent dispatch packets.
In addition to user mode queues and AQL, the HSA runtime exposes various virtual address ranges that can be accessed by one or more of the system's graphics devices, and possibly the host. The exposed virtual address ranges either support a fine grained or a coarse grained access. Updates to memory in a fine grained region are immediately visible to all devices that can access it, but only one device can have access to a coarse grained allocation at a time. Ownership of a coarse grained region can be changed using the HSA runtime memory APIs, but this transfer of ownership must be explicitly done by the host application.
Programmers should consult the HSA Runtime Programmer's Reference Manual for a full description of the HSA Runtime APIs, AQL and the HSA memory policy.
## Known issues
* Each HSA process creates an internal DMA queue, but there is a system-wide limit of four DMA queues. When the limit is reached HSA processes will use internal kernels for copies.
## Artifacts produced by the build
- **libhsakmt (ROCt)** - User-mode API interfaces for interacting with the ROCk driver
libhsakmt is always built as a static library that gets linked into libhsa-runtime, so there is a single library generated called libhsa-runtime64{.so/.a}. If `BUILD_SHARED_LIBS` is not set, this is a shared library by default. Setting `BUILD_SHARED_LIBS` to `OFF` will make it static.
Make sure libhsa-runtime.so is in the library path; e.g.,
```sh
$ LD_LIBRARY_PATH=<rocm install root> ./rocrtst -h # See help options
```
#### kfdtest
1. **Go to kfdtest root**
```sh
cd <rocr-runtime>/libhsakmt/tests/kfdtest
```
2. **Prepare the build directory**
```sh
mkdir build && cd build
```
3. **Configure the build**
Example configuration:
```sh
cmake \
-DCMAKE_PREFIX_PATH="<rocm install root>" \
-DROCM_DIR="$ROCM_INSTALL_PATH" \
..
```
4. **Compile the project**
```sh
make
```
## Using the ROCR Runtime
After installation, you can link against the runtime by using the provided CMake package configurations. For example, to use the ROCR runtime in your project:
