diff options
| author | Peter Marheine <pmarheine@chromium.org> | 2022-05-09 14:55:49 +1000 |
|---|---|---|
| committer | Chromeos LUCI <chromeos-scoped@luci-project-accounts.iam.gserviceaccount.com> | 2022-05-11 00:49:26 +0000 |
| commit | 7afbd0553f0520c17865edb9431f72ae21541acf (patch) | |
| tree | d46489ce046b691a5556440c1afa0b28785933b5 | |
| parent | 16f2a778078f94b4a6c69537322b828cfd3fbf05 (diff) | |
| download | chrome-ec-7afbd0553f0520c17865edb9431f72ae21541acf.tar.gz | |
zephyr/riscv: implement FPU support functions for RV32F
EC floating-point depends on custom implementations of `fqrtf` and
`fabsf` since Zephyr doesn't provide them. Implement them in terms
of the standard F extension's instructions for those operations.
BUG=b:227961840
TEST=Nereid now builds if CONFIG_FPU is enabled
BRANCH=none
Signed-off-by: Peter Marheine <pmarheine@chromium.org>
Change-Id: I904084f297d6a6c85f69feb9e0e72775dbabf83f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3631854
Reviewed-by: Keith Short <keithshort@chromium.org>
| -rw-r--r-- | zephyr/Kconfig | 4 | ||||
| -rw-r--r-- | zephyr/shim/include/fpu.h | 18 |
2 files changed, 18 insertions, 4 deletions
diff --git a/zephyr/Kconfig b/zephyr/Kconfig index 9d8b53ad03..4170225255 100644 --- a/zephyr/Kconfig +++ b/zephyr/Kconfig @@ -339,7 +339,7 @@ config PLATFORM_EC_FLASH_CROS config PLATFORM_EC_FPU bool "Support floating point" - depends on FPU && CPU_CORTEX_M && !NEWLIB_LIBC + depends on FPU && (CPU_CORTEX_M || RISCV) && !NEWLIB_LIBC default y help This enables support for floating point. This is generally already @@ -347,8 +347,6 @@ config PLATFORM_EC_FPU available which are not available with Zephyr's minimal lib: sqrtf() and fabsf(). Enabling this options defines them. - For now this is only supported on Cortex-M4. - config PLATFORM_EC_HOOKS bool "Hooks and deferred compatibility shim" default y diff --git a/zephyr/shim/include/fpu.h b/zephyr/shim/include/fpu.h index da36f50492..8f78fb587d 100644 --- a/zephyr/shim/include/fpu.h +++ b/zephyr/shim/include/fpu.h @@ -47,9 +47,25 @@ static inline float fabsf(float v) return root; } +#elif CONFIG_RISCV +static inline float sqrtf(float v) +{ + float root; + + __asm__("fsqrt.s %0, %1" : "=f"(root) : "f"(v)); + return root; +} + +static inline float fabsf(float v) +{ + float abs; + + __asm__("fabs.s %0, %1" : "=f"(abs) : "f"(v)); + return abs; +} #else #error "Unsupported core: please add an implementation" -#endif /* CONFIG_CPU_CORTEX_M */ +#endif #endif /* CONFIG_PLATFORM_EC_FPU */ |