From a09d4c8d8d5a5f01e0a49aed274fdca3ab5c3966 Mon Sep 17 00:00:00 2001 From: Detlev Casanova Date: Fri, 15 Nov 2024 11:20:41 -0500 Subject: [PATCH 456/480] drm/rockchip: vop2: Add clock resets support At the end of initialization, each VP clock needs to be reset before they can be used. Failing to do so can put the VOP in an undefined state where the generated HDMI signal is either lost or not matching the selected mode. This issue can be reproduced by switching modes multiple times. Depending on the setup, after about 10 mode switches, the signal will be lost and the value in register 0x890 (VSYNCWIDTH + VFRONT) will take the value `0x0000018c`. That makes VSYNCWIDTH=0, which is wrong. Adding the clock resets after the VOP configuration fixes the issue. Signed-off-by: Detlev Casanova --- drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 31 ++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c index 62aee42ccf03..c8480485cb15 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -158,6 +159,7 @@ struct vop2_win { struct vop2_video_port { struct drm_crtc crtc; struct vop2 *vop2; + struct reset_control *dclk_rst; struct clk *dclk; struct clk *dclk_src; unsigned int id; @@ -2134,6 +2136,26 @@ static int us_to_vertical_line(struct drm_display_mode *mode, int us) return us * mode->clock / mode->htotal / 1000; } +static int vop2_clk_reset(struct vop2_video_port *vp) +{ + struct reset_control *rstc = vp->dclk_rst; + struct vop2 *vop2 = vp->vop2; + int ret; + + if (!rstc) + return 0; + + ret = reset_control_assert(rstc); + if (ret < 0) + drm_warn(vop2->drm, "failed to assert reset\n"); + udelay(10); + ret = reset_control_deassert(rstc); + if (ret < 0) + drm_warn(vop2->drm, "failed to deassert reset\n"); + + return ret; +} + static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, struct drm_atomic_state *state) { @@ -2297,6 +2319,8 @@ static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, vop2_crtc_atomic_try_set_gamma(vop2, vp, crtc, crtc_state); + vop2_clk_reset(vp); + drm_crtc_vblank_on(crtc); vop2_unlock(vop2); @@ -3254,6 +3278,13 @@ static int vop2_create_crtcs(struct vop2 *vop2) vp->data = vp_data; snprintf(dclk_name, sizeof(dclk_name), "dclk_vp%d", vp->id); + + vp->dclk_rst = devm_reset_control_get_optional(vop2->dev, dclk_name); + if (IS_ERR(vp->dclk_rst)) { + drm_err(vop2->drm, "failed to get %s reset\n", dclk_name); + return PTR_ERR(vp->dclk_rst); + } + vp->dclk = devm_clk_get(vop2->dev, dclk_name); if (IS_ERR(vp->dclk)) { drm_err(vop2->drm, "failed to get %s\n", dclk_name); -- 2.49.0