removed outdated GPU instructions

README.md

@@ -99,53 +99,7 @@ A complete list of dependencies is maintained [here](https://github.com/spack/sp
 
 For a minimal build, HiOp requires LAPACK and BLAS. These dependencies are automatically detected by the build system. MPI is optional and by default enabled. To disable use cmake option '-DHIOP_USE_MPI=OFF'.
 
-HiOp has support for NVIDIA **GPU-based computations** via CUDA and Magma. To enable the use of GPUs, use cmake with '-DHIOP_USE_GPU=ON'. The build system will automatically search for CUDA Toolkit. For non-standard CUDA Toolkit installations, use '-DHIOP_CUDA_LIB_DIR=/path' and '-DHIOP_CUDA_INCLUDE_DIR=/path'. For "very" non-standard CUDA Toolkit installations, one can specify the directory of cuBlas libraries as well with '-DHIOP_CUBLAS_LIB_DIR=/path'.
-
-### Using RAJA and Umpire portability libraries
-
-Portability libraries allow running HiOp's linear algebra either on host (CPU) or a device (GPU). RAJA and Umpire are disabled by default. You can turn them on together by passing `-DHIOP_USE_RAJA=ON` to CMake. If the two libraries are not automatically found, specify their installation directories like this:
-```shell
-$> cmake -DHIOP_USE_RAJA=ON -DRAJA_DIR=/path/to/raja/dir -Dumpire_DIR=/path/to/umpire/dir
-```
-If the GPU support is enabled, RAJA will run all HiOp linear algebra kernels on GPU, otherwise RAJA will run the kernels on CPU using an OpenMP execution policy.
-
-### Support for GPU computations
-
-When GPU support is on, HiOp requires Magma linear solver library and CUDA Toolkit. Both are detected automatically in most cases. The typical cmake command to enable GPU support in HiOp is
-```shell 
-$> cmake -DHIOP_USE_GPU=ON ..
-```
-
-When Magma is not detected, one can specify its location by passing `-DHIOP_MAGMA_DIR=/path/to/magma/dir` to cmake.
-
-For custom CUDA Toolkit installations, the locations to the (missing/not found) CUDA libraries can be specified to cmake via `-DNAME=/path/cuda/directory/lib`, where `NAME` can be any of  
-```
-CUDA_cublas_LIBRARY
-CUDA_CUDART_LIBRARY
-CUDA_cudadevrt_LIBRARY
-CUDA_cusparse_LIBRARY
-CUDA_cublasLt_LIBRARY
-CUDA_nvblas_LIBRARY
-CUDA_culibos_LIBRARY
- ```
-Below is an example for specifiying `cuBlas`, `cuBlasLt`, and `nvblas` libraries, which were `NOT_FOUND` because of a non-standard CUDA Toolkit instalation:
-```shell 
-$> cmake -DHIOP_USE_GPU=ON -DCUDA_cublas_LIBRARY=/usr/local/cuda-10.2/targets/x86_64-linux/lib/lib64 -DCUDA_cublasLt_LIBRARY=/export/home/petra1/work/installs/cuda10.2.89/targets/x86_64-linux/lib/ -DCUDA_nvblas_LIBRARY=/export/home/petra1/work/installs/cuda10.2.89/targets/x86_64-linux/lib/ .. && make -j && make install
-```
-
-A detailed example on how to compile HiOp straight of the box on `summit.olcf.ornl.gov` is available [here](README_summit.md).
-
-RAJA and UMPIRE dependencies are usually detected by HiOp's cmake build system. 
-
-### Kron reduction
-
-Kron reduction functionality of HiOp is disabled by default. One can enable it by using 
-```shell
-$> rm -rf *; cmake -DHIOP_WITH_KRON_REDUCTION=ON -DUMFPACK_DIR=/Users/petra1/work/installs/SuiteSparse-5.7.1 -DMETIS_DIR=/Users/petra1/work/installs/metis-4.0.3 .. && make -j && make install
-```
-Metis is usually detected automatically and needs not be specified under normal circumstances.
-
-UMFPACK (part of SuiteSparse) and METIS need to be provided as shown above.
+Please note that HiOp has support for GPU computations, for both NVIDIA and AMD hardware, via RAJA and Umpire performance portability libraries.   To quickly enable the use of GPUs, use cmake with '-DHIOP_USE_GPU=ON'.
 
 ## Install with Spack
 
@@ -169,19 +123,6 @@ HiOp supports three types of optimization problems, each with a separate input f
 
 More information on the HiOp interfaces are [here](src/Interface/README.md).
 
-## Running HiOp tests and applications
-
-HiOp is using NVBlas library when built with CUDA support. If you don't specify
-location of the `nvblas.conf` configuration file, you may get an annoying
-warnings. HiOp provides default `nvblas.conf` file and installs it at the same
-location as HiOp libraries. To use it, set environment variable as
-```bash
-$ export NVBLAS_CONFIG_FILE=<hiop install dir>/lib/nvblas.conf
-```
-or, if you are using C-shell, as
-```shell
-$ setenv NVBLAS_CONFIG_FILE <hiop install dir>/lib/nvblas.conf
-```
 
 ## Issues
 Users are highly encouraged to report any issues they found when using HiOp.