I'm sorry my English is so poor.
lspci | grep VGA
07:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cape Verde XT [Radeon HD 7770/8760 / R7 250X]
glxinfo | grep OpenGL
OpenGL vendor string: VMware, Inc.
OpenGL renderer string: llvmpipe (LLVM 6.0, 128 bits)
OpenGL version string: 2.1 Mesa 18.0.0
OpenGL shading language version string: 1.30
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 2.0 Mesa 18.0.0
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 1.0.16
OpenGL ES profile extensions:
When I use fedora 27 it works very well, I use the following method to upgrade to fedora 28:
dnf upgrade --refresh
dnf system-upgrade download --releasever=28 --allowerasing
dnf system-upgrade reboot