mirror of https://gitee.com/openkylin/linux.git
3a715e8040
FPU_STATUS register contains FP exception flags bits which are updated
by core as side-effect of FP instructions but can also be manually
wiggled such as by glibc C99 functions fe{raise,clear,test}except() etc.
To effect the update, the programming model requires OR'ing FWE
bit (31). This bit is write-only and RAZ, meaning it is effectively
auto-cleared after write and thus needs to be set everytime: which
is how glibc implements this.
However there's another usecase of FPU_STATUS update, at the time of
Linux task switch when incoming task value needs to be programmed into
the register. This was added as part of
|
||
|---|---|---|
| .. | ||
| boot | ||
| configs | ||
| include | ||
| kernel | ||
| lib | ||
| mm | ||
| plat-axs10x | ||
| plat-hsdk | ||
| plat-sim | ||
| plat-tb10x | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||