Prior to commit dc6fcaaba5a5 ("drm/omap: Allow build with COMPILE_TEST=y"), it was only possible to build the omapdrm driver with a 4KB page size. After that change, when the PAGE_SIZE is 64KB or larger, clang points out that the driver has some assumptions around the page size implicitly by passing PAGE_SIZE to a parameter with a type of u16: drivers/gpu/drm/omapdrm/omap_gem.c:758:7: error: implicit conversion from 'unsigned long' to 'u16' (aka 'unsigned short') changes value from 65536 to 0 [-Werror,-Wconstant-conversion] 757 | block = tiler_reserve_2d(fmt, omap_obj->width, omap_obj->height, | ~~~~~~~~~~~~~~~~ 758 | PAGE_SIZE); | ^~~~~~~~~ arch/powerpc/include/asm/page.h:25:34: note: expanded from macro 'PAGE_SIZE' 25 | #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) | ~~~~~~~~~~~~~^~~~~~~~~~~~~ drivers/gpu/drm/omapdrm/omap_gem.c:1504:44: error: implicit conversion from 'unsigned long' to 'u16' (aka 'unsigned short') changes value from 65536 to 0 [-Werror,-Wconstant-conversion] 1504 | block = tiler_reserve_2d(fmts[i], w, h, PAGE_SIZE); | ~~~~~~~~~~~~~~~~ ^~~~~~~~~ arch/powerpc/include/asm/page.h:25:34: note: expanded from macro 'PAGE_SIZE' 25 | #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) | ~~~~~~~~~~~~~^~~~~~~~~~~~~ 2 errors generated. As there is a lot of use of a u16 type throughout this driver and it will only ever be run on hardware that has a 4KB page size, just restrict compile testing to when the page size is less than 64KB (as no other issues have been discussed and it keeps compile testing relatively more available). Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> --- drivers/gpu/drm/omapdrm/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/omapdrm/Kconfig b/drivers/gpu/drm/omapdrm/Kconfig index 85ed92042b74..3f7139e211d2 100644 --- a/drivers/gpu/drm/omapdrm/Kconfig +++ b/drivers/gpu/drm/omapdrm/Kconfig @@ -2,7 +2,7 @@ config DRM_OMAP tristate "OMAP DRM" depends on DRM && OF - depends on ARCH_OMAP2PLUS || COMPILE_TEST + depends on ARCH_OMAP2PLUS || (COMPILE_TEST && PAGE_SIZE_LESS_THAN_64KB) select DRM_KMS_HELPER select FB_DMAMEM_HELPERS_DEFERRED if DRM_FBDEV_EMULATION select VIDEOMODE_HELPERS --- base-commit: c62b4fc4b9b86ab35e5c4236f2053ce21ee81ebc change-id: 20240620-omapdrm-restrict-compile-test-to-sub-64kb-page-size-0c8d37e380bb Best regards, -- Nathan Chancellor <nathan@xxxxxxxxxx>