On Wed, Aug 26, 2015 at 01:36:05AM +0530, Animesh Manna wrote: > Dmc will restore the csr program except DC9, cold boot, > warm reset, PCI function level reset, and hibernate/suspend. > > intel_csr_load_program() function is used to load the firmware > data from kernel memory to csr address space. > > All values of csr address space will be zero if it got reset and > the first byte of csr program is always a non-zero if firmware > is loaded successfuly. Based on hardware status will load the > firmware. > > Without this condition check if we overwrite the firmware data the > counters exposed for dc5/dc6 (help for debugging) will be nullified. > > v1: Initial version. > > v2: Based on review comments from Daniel, > - Added a check to know hardware status and load the firmware if not loaded. > > Cc: Daniel Vetter <daniel.vetter@xxxxxxxxx> > Cc: Damien Lespiau <damien.lespiau@xxxxxxxxx> > Cc: Imre Deak <imre.deak@xxxxxxxxx> > Cc: Sunil Kamath <sunil.kamath@xxxxxxxxx> > Signed-off-by: Animesh Manna <animesh.manna@xxxxxxxxx> > Signed-off-by: Vathsala Nagaraju <vathsala.nagaraju@xxxxxxxxx> > --- > drivers/gpu/drm/i915/intel_csr.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c > index ba1ae03..682cc26 100644 > --- a/drivers/gpu/drm/i915/intel_csr.c > +++ b/drivers/gpu/drm/i915/intel_csr.c > @@ -252,6 +252,15 @@ void intel_csr_load_program(struct drm_device *dev) > return; > } > > + /* > + * Dmc will restore the csr the program except DC9, cold boot, > + * warm reset, PCI function level reset, and hibernate/suspend. > + * This condition will help to check if csr address space is reset/ > + * not loaded. > + */ Atm we call this from driver load and resume, which doesn seem to cover all the cases you mention in the comment. Should this be a WARN_ON instead? Or do we have troubles in our init sequence where we load too many times? Either way I can't reconcile your commit message with the comment here. -Daniel > + if (I915_READ(CSR_PROGRAM_BASE)) > + return; > + > mutex_lock(&dev_priv->csr_lock); > fw_size = dev_priv->csr.dmc_fw_size; > for (i = 0; i < fw_size; i++) > -- > 2.0.2 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
