Hi Anatoliy, On Fri, Jan 19, 2024 at 05:53:30AM +0000, Klymenko, Anatoliy wrote: > On Wed, 17 Jan 2024 16:20:10 +0200, Tomi Valkeinen wrote: > > On 13/01/2024 01:42, Anatoliy Klymenko wrote: > > > Filter out status register against interrupts' mask. > > > Some events are being reported via DP status register, even if > > > corresponding interrupts have been disabled. Avoid processing of such > > > events in interrupt handler context. > > > > The subject talks about vblank and live mode, the the description doesn't. Can > > you elaborate in the desc a bit about when this is an issue and why it wasn't > > before? > > Yes, I should make patch comment more consistent and elaborate. I will fix it in the next version. Thank you. > > > > > > Signed-off-by: Anatoliy Klymenko <anatoliy.klymenko@xxxxxxx> > > > --- > > > drivers/gpu/drm/xlnx/zynqmp_dp.c | 11 +++++++++-- > > > 1 file changed, 9 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c > > > b/drivers/gpu/drm/xlnx/zynqmp_dp.c > > > index d60b7431603f..571c5dbc97e5 100644 > > > --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c > > > +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c > > > @@ -1624,8 +1624,16 @@ static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data) > > > u32 status, mask; > > > > > > status = zynqmp_dp_read(dp, ZYNQMP_DP_INT_STATUS); > > > + zynqmp_dp_write(dp, ZYNQMP_DP_INT_STATUS, status); > > > mask = zynqmp_dp_read(dp, ZYNQMP_DP_INT_MASK); > > > - if (!(status & ~mask)) > > > + > > > + /* > > > + * Status register may report some events, which corresponding interrupts > > > + * have been disabled. Filter out those events against interrupts' mask. > > > + */ > > > + status &= ~mask; > > > + > > > + if (!status) > > > return IRQ_NONE; > > > > > > /* dbg for diagnostic, but not much that the driver can do */ > > > @@ -1634,7 +1642,6 @@ static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data) > > > if (status & ZYNQMP_DP_INT_CHBUF_OVERFLW_MASK) > > > dev_dbg_ratelimited(dp->dev, "overflow interrupt\n"); > > > > > > - zynqmp_dp_write(dp, ZYNQMP_DP_INT_STATUS, status); > > > > > > if (status & ZYNQMP_DP_INT_VBLANK_START) > > > zynqmp_dpsub_drm_handle_vblank(dp->dpsub); > > > > Moving the zynqmp_dp_write() is not related to this fix, is it? I think it should be in > > a separate patch. > > The sole purpose of zynqmp_dp_write() is to clear status register. The > sooner we do it the better (after reading status in the local variable > of course). No disagreement about that. Tomi's point is that it's a good change, but it should be done in a separate patch, by itself, not bundled with other changes. The usual rule in the kernel is "one change, one commit". > We can also reuse status variable for in-place filtering > against the interrupt mask, which makes this change dependent on > zynqmp_dp_write() reordering. I will add a comment explaining this. Is > it ok? -- Regards, Laurent Pinchart
