Hi Philipp, On Mon, 27 Jul 2026 09:35:38 +0200, Philipp Zabel wrote: > On Sa, 2026-07-25 at 00:51 -0400, Cody Kang via B4 Relay wrote: > > From: Cody Kang <[email protected]> > > > > Add the atomic KMS implementation on top of the hardware backend: one > > CRTC and one primary plane per DPU instance. atomic_check validates > > the plane rectangle 1:1 against the mode and sizes the per-channel FBC > > line buffer; atomic commit builds the cmdlist batches, maps the > > framebuffer through the DMMU and arms the cfg-ready handshake, with > > vblank events driven from the DPU interrupt. > > > > Signed-off-by: Cody Kang <[email protected]> > > --- > > drivers/gpu/drm/spacemit/spacemit_crtc.c | 815 > > +++++++++++++++++++++++++++++ > > drivers/gpu/drm/spacemit/spacemit_planes.c | 376 +++++++++++++ > > 2 files changed, 1191 insertions(+) > > > > diff --git a/drivers/gpu/drm/spacemit/spacemit_crtc.c > > b/drivers/gpu/drm/spacemit/spacemit_crtc.c > > new file mode 100644 > > index 000000000000..b75ff6320501 > > --- /dev/null > > +++ b/drivers/gpu/drm/spacemit/spacemit_crtc.c > > @@ -0,0 +1,815 @@ > [...] > > +/* > > + * The assert and deassert orders are not mirror images: the hardware wants > > + * these. > > + */ > > +static void dpu_reset_assert(struct device *dev, const char *name, > > + struct reset_control *rstc) > > +{ > > + int ret = reset_control_assert(rstc); > > + > > + if (ret) > > + dev_warn(dev, "failed to assert %s reset: %d\n", name, ret); > > +} > > + > > +static void dpu_reset_deassert(struct device *dev, const char *name, > > + struct reset_control *rstc) > > +{ > > + int ret = reset_control_deassert(rstc); > > + > > + if (ret) > > + dev_warn(dev, "failed to deassert %s reset: %d\n", name, ret); > > +} > > + > > +static int dpu_pm_suspend(struct device *dev) > > +{ > > + struct spacemit_drm_private *priv = dev_get_drvdata(dev); > > + struct spacemit_crtc *a_crtc = priv->a_crtc; > > + > > + /* > > + * Assert before gating: a reset asserted into an already-gated block > > + * has no clock edges to propagate on and leaves the register file > > + * untouched. > > + */ > > + dpu_reset_assert(dev, "lcd", a_crtc->lcd_reset); > > + dpu_reset_assert(dev, "esc", a_crtc->esc_reset); > > + dpu_reset_assert(dev, "mclk", a_crtc->mclk_reset); > > It looks like these three are mirrored, and could be handled by > reset_control_bulk_assert/deassert().
Thanks for the review. Indeed, reset_control_bulk_deassert() walking the array in reverse gives exactly the mirrored order the hardware wants. Will fix in v2. Cody
