On Mon, May 22, 2017 at 11:37 PM, Arnd Bergmann arnd@arndb.de wrote:
On Mon, May 22, 2017 at 6:32 PM, Krzysztof Kozlowski krzk@kernel.org wrote:
On Mon, May 22, 2017 at 05:20:08PM +0200, Arnd Bergmann wrote:
The driver is written in a way to enable compile-testing without CONFIG_ARM_AMBA, but it just causes needless warnings:
drivers/gpu/drm/pl111/pl111_drv.c:149:26: error: 'pl111_drm_driver' defined but not used [-Werror=unused-variable] drivers/gpu/drm/pl111/pl111_drv.c:81:12: error: 'pl111_modeset_init' defined but not used [-Werror=unused-function]
This removes the #ifdef instead, and adds a dependency on ARM_AMBA to only let us build the driver when the base support is enabled.
Unfortunately, this requires removing one redundant 'select ARM_AMBA' line from mach-s3c64xx to avoid a circular dependency.
It might be good to allow manually enabling ARM_AMBA when COMPILE_TEST is turned on, but that should be a separate patch and may cause other build regressions.
Fixes: bed41005e617 ("drm/pl111: Initial drm/kms driver for pl111") Signed-off-by: Arnd Bergmann arnd@arndb.de
arch/arm/mach-s3c64xx/Kconfig | 1 - drivers/gpu/drm/pl111/Kconfig | 1 + drivers/gpu/drm/pl111/pl111_drv.c | 2 -- 3 files changed, 1 insertion(+), 3 deletions(-)
diff --git a/arch/arm/mach-s3c64xx/Kconfig b/arch/arm/mach-s3c64xx/Kconfig index 459214fa20b4..5ee5ad74a3d6 100644 --- a/arch/arm/mach-s3c64xx/Kconfig +++ b/arch/arm/mach-s3c64xx/Kconfig @@ -40,7 +40,6 @@ config CPU_S3C6410
config S3C64XX_PL080 def_bool DMADEVICES
select ARM_AMBAI must admit that I miss how pl111 DRM driver create circular dependency with S3C64XX_PL080 (or AMBA_PL08X?). Maybe it is unrelated change and should be a separate patch?
When I add 'depends on ARM_AMBA' for pl111, I get this dependency loop:
drivers/i2c/Kconfig:7: symbol I2C is selected by FB_DDC For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/video/fbdev/Kconfig:63: symbol FB_DDC is selected by FB_CYBER2000_DDC For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/video/fbdev/Kconfig:381: symbol FB_CYBER2000_DDC depends on FB_CYBER2000 For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/video/fbdev/Kconfig:369: symbol FB_CYBER2000 depends on FB For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/video/fbdev/Kconfig:5: symbol FB is selected by DRM_KMS_FB_HELPER For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/gpu/drm/Kconfig:72: symbol DRM_KMS_FB_HELPER is selected by DRM_KMS_CMA_HELPER For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/gpu/drm/Kconfig:137: symbol DRM_KMS_CMA_HELPER is selected by DRM_PL111 For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/gpu/drm/pl111/Kconfig:1: symbol DRM_PL111 depends on ARM_AMBA For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/amba/Kconfig:1: symbol ARM_AMBA is selected by S3C64XX_PL080 For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" arch/arm/mach-s3c64xx/Kconfig:42: symbol S3C64XX_PL080 default value contains DMADEVICES For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" drivers/dma/Kconfig:5: symbol DMADEVICES is selected by SND_SOC_SH4_SIU For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" sound/soc/sh/Kconfig:29: symbol SND_SOC_SH4_SIU is selected by SND_SIU_MIGOR For a resolution refer to Documentation/kbuild/kconfig-language.txt subsection "Kconfig recursive dependency limitations" sound/soc/sh/Kconfig:59: symbol SND_SIU_MIGOR depends on I2C
We could break the loop at any of those places, but the S3C64XX_PL080 symbol seemed the easiest way since the 'select' there is completely unnecessary and it directly relates to the change I made in PL111.
Assuming ARM_AMBA is unnecessary here, then it should be unnecessary in other platforms as well but we have it (git grep 'select ARM_AMBA'). The ARM_AMBA is a dependency of AMBA_PL08X which is selected by S3C64xx... so IMHO this is needed.
Best regards, Krzysztof