On 08/04/2024 20:04, Ville Syrjala wrote:
From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> __iowmb() isn't available on most architectures. Make its use optional so that the driver can be built on other architectures with COMPILE_TEST=y. Cc: Jyri Sarha <jyri.sarha@xxxxxx> Cc: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/tilcdc/tilcdc_regs.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/tilcdc/tilcdc_regs.h b/drivers/gpu/drm/tilcdc/tilcdc_regs.h index f90e2dc3457c..44e4ada30fba 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_regs.h +++ b/drivers/gpu/drm/tilcdc/tilcdc_regs.h @@ -125,7 +125,9 @@ static inline void tilcdc_write64(struct drm_device *dev, u32 reg, u64 data) #if defined(iowrite64) && !defined(iowrite64_is_nonatomic) iowrite64(data, addr); #else +#ifdef __iowmb __iowmb(); +#endif /* This compiles to strd (=64-bit write) on ARM7 */ *(volatile u64 __force *)addr = __cpu_to_le64(data); #endif
As the memory barrier is an important part there, would it be better to ifdef based on COMPILE_TEST, to make it clear why it's being done?
Tomi
