Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
Pre-existing issues: - [High] The `atomic_check` callback incorrectly modifies driver private hardware state (`hdmi->tmds_char_rate`) and invokes PHY configuration functions (`phy_configure`), violating the stateless nature of atomic checks. -- commit 6a5a6d9518ed6863c0bd7d0093aee570c295458a Author: Cristian Ciocaltea <[email protected]> drm/rockchip: dw_hdmi_qp: Support 10-bit YUV422 output format This commit adds support for 10-bit YUV 4:2:2 output to the DW HDMI QP encoder by configuring the PHY with 8 bpc when YUV 4:2:2 is in use. This keeps the output clock aligned with the TMDS character rate. > diff --git a/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c > b/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c > index 9c4cf68d79d50..78473f9a0fce3 100644 > --- a/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c > +++ b/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c > @@ -215,6 +215,7 @@ dw_hdmi_qp_rockchip_encoder_atomic_check(struct > drm_encoder *encoder, > s->output_mode = ROCKCHIP_OUT_MODE_AAAA; > break; > case MEDIA_BUS_FMT_UYVY8_1X16: > + case MEDIA_BUS_FMT_UYVY10_1X20: > s->output_mode = ROCKCHIP_OUT_MODE_YUV422; > break; > case MEDIA_BUS_FMT_UYYVYY8_0_5X24: > @@ -226,7 +227,14 @@ dw_hdmi_qp_rockchip_encoder_atomic_check(struct > drm_encoder *encoder, > } > > phy_cfg.hdmi.tmds_char_rate = conn_state->hdmi.tmds_char_rate; > - phy_cfg.hdmi.bpc = conn_state->hdmi.output_bpc; > + /* > + * YUV422 always transmits two 12-bit components per clock cycle, > + * regardless of the color depth, which from a rate perspective is > + * equivalent to three 8-bit RGB components. Force 8 bpc here to > + * keep the PHY PLL output aligned with the TMDS character rate. > + */ > + phy_cfg.hdmi.bpc = (s->output_mode == ROCKCHIP_OUT_MODE_YUV422 ? > + 8 : conn_state->hdmi.output_bpc); > > ret = phy_configure(hdmi->phy, &phy_cfg); > if (!ret) { > hdmi->tmds_char_rate = conn_state->hdmi.tmds_char_rate; [Severity: High] This isn't a bug introduced by this patch, but does this violate the DRM atomic API contract? Modifying physical PHY hardware state and persistent driver state (hdmi->tmds_char_rate) during the stateless atomic check phase could cause problems if userspace issues a test-only atomic commit. If a compositor issues DRM_MODE_ATOMIC_TEST_ONLY, phy_configure() will program the PHY hardware and hdmi->tmds_char_rate will be mutated. When the test-only commit is discarded, the PHY is left in an unexpected state. A subsequent real commit might then hit the fast-path check earlier in this function: if (hdmi->tmds_char_rate == conn_state->hdmi.tmds_char_rate && s->output_bpc == conn_state->hdmi.output_bpc && s->bus_format == ingest_fmt) return 0; and skip PHY configuration entirely, leaving the hardware incorrectly configured. Could this lead to hardware misconfiguration, visual glitches, or black screens? > s->output_type = DRM_MODE_CONNECTOR_HDMIA; > s->output_bpc = conn_state->hdmi.output_bpc; > s->bus_format = ingest_fmt; -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=11
