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?
> Signed-off-by: Anatoliy Klymenko <anatoliy.klymenko@amd.com>
> ---
> 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.
Tomi