[RFC PATCH] drm/msm: lookup the ICC paths in both mdp5/dpu and mdss devices

[Yassine Oudjana]

On Friday, August 5th, 2022 at 12:56 PM, Dmitry Baryshkov <dmitry.baryshkov at linaro.org> wrote:

> The commit 6874f48bb8b0 ("drm/msm: make mdp5/dpu devices master
> components") changed the MDP5 driver to look for the interconnect paths
> in the MDSS device rather than in the MDP5 device itself. This was left
> unnoticed since on my testing devices the interconnects probably didn't
> reach the sync state.
>
> Rather than just using the MDP5 device for ICC path lookups for the MDP5
> devices, introduce an additional helper to check both MDP5/DPU and MDSS
> nodes. This will be helpful for the MDP5->DPU conversion, since the
>
> driver will have to check both nodes.
>
> Fixes: 6874f48bb8b0 ("drm/msm: make mdp5/dpu devices master components")
> Reported-by: Marijn Suijten marijn.suijten at somainline.org
>
> Reported-by: Yassine Oudjana y.oudjana at protonmail.com
>
> Signed-off-by: Dmitry Baryshkov dmitry.baryshkov at linaro.org
>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 7 ++-----
> drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c | 9 +++------
> drivers/gpu/drm/msm/msm_drv.h | 2 ++
> drivers/gpu/drm/msm/msm_io_utils.c | 22 ++++++++++++++++++++++
> 4 files changed, 29 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index e23e2552e802..9eff6c2b1917 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -383,12 +383,9 @@ static int dpu_kms_parse_data_bus_icc_path(struct dpu_kms *dpu_kms)
> struct icc_path *path1;
> struct drm_device *dev = dpu_kms->dev;
>
> struct device *dpu_dev = dev->dev;
>
> - struct device *mdss_dev = dpu_dev->parent;
>
>
> - /* Interconnects are a part of MDSS device tree binding, not the
> - * MDP/DPU device. */
> - path0 = of_icc_get(mdss_dev, "mdp0-mem");
> - path1 = of_icc_get(mdss_dev, "mdp1-mem");
> + path0 = msm_icc_get(dpu_dev, "mdp0-mem");
> + path1 = msm_icc_get(dpu_dev, "mdp1-mem");
>
> if (IS_ERR_OR_NULL(path0))
> return PTR_ERR_OR_ZERO(path0);
> diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
> index 3d5621a68f85..b0c372fef5d5 100644
> --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
> +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
> @@ -921,12 +921,9 @@ static int mdp5_init(struct platform_device *pdev, struct drm_device *dev)
>
> static int mdp5_setup_interconnect(struct platform_device pdev)
> {
> - / Interconnects are a part of MDSS device tree binding, not the
> - * MDP5 device. */
> - struct device *mdss_dev = pdev->dev.parent;
>
> - struct icc_path *path0 = of_icc_get(mdss_dev, "mdp0-mem");
> - struct icc_path *path1 = of_icc_get(mdss_dev, "mdp1-mem");
> - struct icc_path *path_rot = of_icc_get(mdss_dev, "rotator-mem");
> + struct icc_path *path0 = msm_icc_get(&pdev->dev, "mdp0-mem");
>
> + struct icc_path *path1 = msm_icc_get(&pdev->dev, "mdp1-mem");
>
> + struct icc_path *path_rot = msm_icc_get(&pdev->dev, "rotator-mem");
>
>
> if (IS_ERR(path0))
> return PTR_ERR(path0);
> diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
> index 08388d742d65..d38510f6dbf5 100644
> --- a/drivers/gpu/drm/msm/msm_drv.h
> +++ b/drivers/gpu/drm/msm/msm_drv.h
> @@ -441,6 +441,8 @@ void __iomem *msm_ioremap_size(struct platform_device *pdev, const char *name,
> phys_addr_t *size);
> void __iomem *msm_ioremap_quiet(struct platform_device *pdev, const char *name);
>
> +struct icc_path *msm_icc_get(struct device *dev, const char *name);
> +
> #define msm_writel(data, addr) writel((data), (addr))
> #define msm_readl(addr) readl((addr))
>
> diff --git a/drivers/gpu/drm/msm/msm_io_utils.c b/drivers/gpu/drm/msm/msm_io_utils.c
> index 7b504617833a..d02cd29ce829 100644
> --- a/drivers/gpu/drm/msm/msm_io_utils.c
> +++ b/drivers/gpu/drm/msm/msm_io_utils.c
> @@ -5,6 +5,8 @@
> * Author: Rob Clark robdclark at gmail.com
>
> */
>
> +#include <linux/interconnect.h>
>
> +
> #include "msm_drv.h"
>
> /*
> @@ -124,3 +126,23 @@ void msm_hrtimer_work_init(struct msm_hrtimer_work *work,
> work->worker = worker;
>
> kthread_init_work(&work->work, fn);
>
> }
> +
> +struct icc_path *msm_icc_get(struct device *dev, const char *name)
> +{
> + struct device *mdss_dev = dev->parent;
>
> + struct icc_path path;
> +
> + path = of_icc_get(dev, name);
> + if (path)
> + return path;
> +
> + /
> + * If there are no interconnects attached to the corresponding device
> + * node, of_icc_get() will return NULL.
> + *
> + * If the MDP5/DPU device node doesn't have interconnects, lookup the
> + * path in the parent (MDSS) device.
> + */
> + return of_icc_get(mdss_dev, name);
> +
> +}
> --
> 2.35.1

Tested-by: Yassine Oudjana <y.oudjana at protonmail.com> # msm8996