On 12/06/17 01:30, Logan Gunthorpe wrote: > Add a check to ensure iowrite64 is only used if it is atomic. > > It was decided in [1] that the tilcdc driver should not be using an > atomic operation (so it was left out of this patchset). However, it turns > out that through the drm code, a nonatomic header is actually included: > > include/linux/io-64-nonatomic-lo-hi.h > is included from include/drm/drm_os_linux.h:9:0, > from include/drm/drmP.h:74, > from include/drm/drm_modeset_helper.h:26, > from include/drm/drm_atomic_helper.h:33, > from drivers/gpu/drm/tilcdc/tilcdc_crtc.c:19: > > And thus, without this change, this patchset would inadvertantly > change the behaviour of the tilcdc driver. > > [1] > lkml.kernel.org/r/cak8p3a2hho_zcnstzq7hmwsz5la5thu19fwzpun16imnyyn...@mail.gmail.com > > Signed-off-by: Logan Gunthorpe <log...@deltatee.com> > Reviewed-by: Andy Shevchenko <andy.shevche...@gmail.com> > Cc: Jyri Sarha <jsa...@ti.com> > Cc: Arnd Bergmann <a...@arndb.de> > Cc: Tomi Valkeinen <tomi.valkei...@ti.com> > Cc: David Airlie <airl...@linux.ie>
I guess it is about time for me to pick this up for the next pull request. Thanks, Jyri > --- > drivers/gpu/drm/tilcdc/tilcdc_regs.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/tilcdc/tilcdc_regs.h > b/drivers/gpu/drm/tilcdc/tilcdc_regs.h > index 9d528c0a67a4..5048ebb86835 100644 > --- a/drivers/gpu/drm/tilcdc/tilcdc_regs.h > +++ b/drivers/gpu/drm/tilcdc/tilcdc_regs.h > @@ -133,7 +133,7 @@ static inline void tilcdc_write64(struct drm_device *dev, > u32 reg, u64 data) > struct tilcdc_drm_private *priv = dev->dev_private; > volatile void __iomem *addr = priv->mmio + reg; > > -#ifdef iowrite64 > +#if defined(iowrite64) && !defined(iowrite64_is_nonatomic) > iowrite64(data, addr); > #else > __iowmb(); > -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
