On 04/03/2024 09:08, Boris Brezillon wrote:
> panthor_device_resume/suspend() are only compiled when CONFIG_PM is
> enabled but panthro_drv.c doesn't use the pm_ptr() macro to conditionally
> discard resume/suspend assignments, which causes undefined symbol
> errors at link time when !PM.
>
> We could fix that by using pm_ptr(), but supporting the !PM case makes
> little sense (the whole point of these embedded GPUs is to be low power,
> so proper PM is a basic requirement in that case). So let's just enforce
> the presence of CONFIG_PM with a Kconfig dependency instead.
>
> If someone needs to relax this dependency, it can be done in a follow-up.
>
> Reported-by: kernel test robot <l...@intel.com>
> Closes:
> https://lore.kernel.org/oe-kbuild-all/202403031944.eoimq8wk-...@intel.com/
> Signed-off-by: Boris Brezillon <boris.brezil...@collabora.com>
Seems reasonable, it should be easy to relax the CONFIG_PM condition in
the future if anyone has an actual need.
Reviewed-by: Steven Price <steven.pr...@arm.com>
> ---
> drivers/gpu/drm/panthor/Kconfig | 1 +
> drivers/gpu/drm/panthor/panthor_device.c | 2 --
> 2 files changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/panthor/Kconfig b/drivers/gpu/drm/panthor/Kconfig
> index 55b40ad07f3b..fdce7c1b2310 100644
> --- a/drivers/gpu/drm/panthor/Kconfig
> +++ b/drivers/gpu/drm/panthor/Kconfig
> @@ -6,6 +6,7 @@ config DRM_PANTHOR
> depends on ARM || ARM64 || COMPILE_TEST
> depends on !GENERIC_ATOMIC64 # for IOMMU_IO_PGTABLE_LPAE
> depends on MMU
> + depends on PM
> select DEVFREQ_GOV_SIMPLE_ONDEMAND
> select DRM_EXEC
> select DRM_GEM_SHMEM_HELPER
> diff --git a/drivers/gpu/drm/panthor/panthor_device.c
> b/drivers/gpu/drm/panthor/panthor_device.c
> index 68e467ee458a..efea29143a54 100644
> --- a/drivers/gpu/drm/panthor/panthor_device.c
> +++ b/drivers/gpu/drm/panthor/panthor_device.c
> @@ -403,7 +403,6 @@ int panthor_device_mmap_io(struct panthor_device *ptdev,
> struct vm_area_struct *
> return 0;
> }
>
> -#ifdef CONFIG_PM
> int panthor_device_resume(struct device *dev)
> {
> struct panthor_device *ptdev = dev_get_drvdata(dev);
> @@ -548,4 +547,3 @@ int panthor_device_suspend(struct device *dev)
> mutex_unlock(&ptdev->pm.mmio_lock);
> return ret;
> }
> -#endif
