Hi, On Fri, Dec 20, 2019 at 9:03 PM Artur Świgoń <a.swigon@xxxxxxxxxxx> wrote: > > From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > > This patch adds interconnect support to exynos-mixer. The mixer works > the same as before when CONFIG_INTERCONNECT is 'n'. The patch description doesn't include why interconnect is required and what to do. > > Co-developed-by: Artur Świgoń <a.swigon@xxxxxxxxxxx> > Signed-off-by: Artur Świgoń <a.swigon@xxxxxxxxxxx> > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > --- > drivers/gpu/drm/exynos/exynos_mixer.c | 71 +++++++++++++++++++++++++-- > 1 file changed, 66 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c > index 6cfdb95fef2f..a7e7240a055f 100644 > --- a/drivers/gpu/drm/exynos/exynos_mixer.c > +++ b/drivers/gpu/drm/exynos/exynos_mixer.c > @@ -13,6 +13,7 @@ > #include <linux/component.h> > #include <linux/delay.h> > #include <linux/i2c.h> > +#include <linux/interconnect.h> > #include <linux/interrupt.h> > #include <linux/irq.h> > #include <linux/kernel.h> > @@ -97,6 +98,7 @@ struct mixer_context { > struct exynos_drm_crtc *crtc; > struct exynos_drm_plane planes[MIXER_WIN_NR]; > unsigned long flags; > + struct icc_path *soc_path; > > int irq; > void __iomem *mixer_regs; > @@ -931,6 +933,40 @@ static void mixer_disable_vblank(struct exynos_drm_crtc *crtc) > mixer_reg_writemask(mixer_ctx, MXR_INT_EN, 0, MXR_INT_EN_VSYNC); > } > > +static void mixer_set_memory_bandwidth(struct exynos_drm_crtc *crtc) > +{ > + struct drm_display_mode *mode = &crtc->base.state->adjusted_mode; > + struct mixer_context *ctx = crtc->ctx; > + unsigned long bw, bandwidth = 0; > + int i, j, sub; > + > + if (!ctx->soc_path) > + return; > + > + for (i = 0; i < MIXER_WIN_NR; i++) { > + struct drm_plane *plane = &ctx->planes[i].base; > + const struct drm_format_info *format; > + > + if (plane->state && plane->state->crtc && plane->state->fb) { > + format = plane->state->fb->format; > + bw = mode->hdisplay * mode->vdisplay * > + drm_mode_vrefresh(mode); > + if (mode->flags & DRM_MODE_FLAG_INTERLACE) > + bw /= 2; > + for (j = 0; j < format->num_planes; j++) { > + sub = j ? (format->vsub * format->hsub) : 1; > + bandwidth += format->cpp[j] * bw / sub; > + } > + } > + } > + > + /* add 20% safety margin */ > + bandwidth = bandwidth / 4 * 5; > + > + dev_dbg(ctx->dev, "exynos-mixer: safe bandwidth %ld Bps\n", bandwidth); > + icc_set_bw(ctx->soc_path, Bps_to_icc(bandwidth), 0); > +} I recommend that add the role of this function in order to guarantee the minimum bandwidth to prevent performance drop or h/w issue. > + > static void mixer_atomic_begin(struct exynos_drm_crtc *crtc) > { > struct mixer_context *ctx = crtc->ctx; > @@ -982,6 +1018,7 @@ static void mixer_atomic_flush(struct exynos_drm_crtc *crtc) > if (!test_bit(MXR_BIT_POWERED, &mixer_ctx->flags)) > return; > > + mixer_set_memory_bandwidth(crtc); > mixer_enable_sync(mixer_ctx); > exynos_crtc_handle_event(crtc); > } > @@ -1029,6 +1066,7 @@ static void mixer_disable(struct exynos_drm_crtc *crtc) > for (i = 0; i < MIXER_WIN_NR; i++) > mixer_disable_plane(crtc, &ctx->planes[i]); > > + mixer_set_memory_bandwidth(crtc); > exynos_drm_pipe_clk_enable(crtc, false); > > pm_runtime_put(ctx->dev); > @@ -1220,12 +1258,22 @@ static int mixer_probe(struct platform_device *pdev) > struct device *dev = &pdev->dev; > const struct mixer_drv_data *drv; > struct mixer_context *ctx; > + struct icc_path *path; > int ret; > > + /* > + * Returns NULL if CONFIG_INTERCONNECT is disabled. > + * May return ERR_PTR(-EPROBE_DEFER). > + */ > + path = of_icc_get(dev, NULL); > + if (IS_ERR(path)) > + return PTR_ERR(path); > + > ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); > if (!ctx) { > DRM_DEV_ERROR(dev, "failed to alloc mixer context.\n"); > - return -ENOMEM; > + ret = -ENOMEM; > + goto err; > } > > drv = of_device_get_match_data(dev); > @@ -1233,6 +1281,7 @@ static int mixer_probe(struct platform_device *pdev) > ctx->pdev = pdev; > ctx->dev = dev; > ctx->mxr_ver = drv->version; > + ctx->soc_path = path; > > if (drv->is_vp_enabled) > __set_bit(MXR_BIT_VP_ENABLED, &ctx->flags); > @@ -1242,17 +1291,29 @@ static int mixer_probe(struct platform_device *pdev) > platform_set_drvdata(pdev, ctx); > > ret = component_add(&pdev->dev, &mixer_component_ops); > - if (!ret) > - pm_runtime_enable(dev); > + if (ret < 0) > + goto err; > + > + pm_runtime_enable(dev); > + > + return 0; > + > +err: > + icc_put(path); > > return ret; > } > > static int mixer_remove(struct platform_device *pdev) > { > - pm_runtime_disable(&pdev->dev); > + struct device *dev = &pdev->dev; > + struct mixer_context *ctx = dev_get_drvdata(dev); > + > + pm_runtime_disable(dev); > + > + component_del(dev, &mixer_component_ops); > > - component_del(&pdev->dev, &mixer_component_ops); > + icc_put(ctx->soc_path); > > return 0; > } > -- > 2.17.1 > Basically, I agree this patch about using ICC feature to guarantee the minimum bandwidth. But, I don't have the knowledge of exynos-mixer.c. So, just I reviewed the part of ICC usage. After digging the exynos-mixer.c, I'll reply the reviewed tag. Thanks. -- Best Regards, Chanwoo Choi _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel