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Date:   Tue, 3 Jan 2023 15:52:32 +0530
From:   Rahul T R <r-ravikumar@ti.com>
To:     Laurent Pinchart <laurent.pinchart@ideasonboard.com>
CC:     <dri-devel@lists.freedesktop.org>, <robh+dt@kernel.org>,
        <krzysztof.kozlowski+dt@linaro.org>,
        <tomi.valkeinen@ideasonboard.com>, <andrzej.hajda@intel.com>,
        <narmstrong@baylibre.com>, <robert.foss@linaro.org>,
        <jonas@kwiboo.se>, <jernej.skrabec@gmail.com>, <airlied@linux.ie>,
        <daniel@ffwll.ch>, <p.zabel@pengutronix.de>,
        <linux-kernel@vger.kernel.org>, <jpawar@cadence.com>,
        <sjakhade@cadence.com>, <mparab@cadence.com>, <a-bhatia1@ti.com>,
        <devicetree@vger.kernel.org>, <vigneshr@ti.com>,
        <lee.jones@linaro.org>
Subject: Re: [PATCH v10 5/5] drm/bridge: cdns-dsi: Add support for J721E
 wrapper
Message-ID: <20230103102231.xl3ccvz4zrymnk75@uda0490373>
References: <20230102100942.1828-1-r-ravikumar@ti.com>
 <20230102100942.1828-6-r-ravikumar@ti.com>
 <Y7Lc3m+EatH7x2w7@pendragon.ideasonboard.com>
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Hi Laurent,

Thanks for the detailed review
I have addressed the review comments
and sent v11 of this series

On 15:32-20230102, Laurent Pinchart wrote:
> Hi Rahul,
> 
> Thank you for the patch.
> 
> On Mon, Jan 02, 2023 at 03:39:42PM +0530, Rahul T R wrote:
> > Add support for wrapper settings for DSI bridge on
> > j721e. Also enable DPI0
> > 
> > ---------------      -----------------------
> > |      -------|      |-------              |
> > | DSS  | DPI2 |----->| DPI0 |  DSI Wrapper |
> > |      -------|      |-------              |
> > ---------------      -----------------------
> > 
> > As shown above DPI2 output of DSS is connected
> > to DPI0 input of DSI Wrapper, DSI wrapper
> > gives control wheather to enable/disable DPI0
> > input. In j721e above is the only configuration
> > supported
> 
> You can also go up to 72 characters per line here :-)
> 
> > Signed-off-by: Rahul T R <r-ravikumar@ti.com>
> > Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> > ---
> >  drivers/gpu/drm/bridge/cadence/Kconfig        | 10 ++++
> >  drivers/gpu/drm/bridge/cadence/Makefile       |  1 +
> >  .../gpu/drm/bridge/cadence/cdns-dsi-core.c    | 35 ++++++++++++-
> >  .../gpu/drm/bridge/cadence/cdns-dsi-core.h    | 13 +++++
> >  .../gpu/drm/bridge/cadence/cdns-dsi-j721e.c   | 51 +++++++++++++++++++
> >  .../gpu/drm/bridge/cadence/cdns-dsi-j721e.h   | 16 ++++++
> >  6 files changed, 125 insertions(+), 1 deletion(-)
> >  create mode 100644 drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.c
> >  create mode 100644 drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.h
> > 
> > diff --git a/drivers/gpu/drm/bridge/cadence/Kconfig b/drivers/gpu/drm/bridge/cadence/Kconfig
> > index 8fbb46c66094..f8ea0393fe8a 100644
> > --- a/drivers/gpu/drm/bridge/cadence/Kconfig
> > +++ b/drivers/gpu/drm/bridge/cadence/Kconfig
> > @@ -36,3 +36,13 @@ config DRM_CDNS_DSI
> >  	help
> >  	  Support Cadence DPI to DSI bridge. This is an internal
> >  	  bridge and is meant to be directly embedded in a SoC.
> > +
> > +if DRM_CDNS_DSI
> > +
> > +config DRM_CDNS_DSI_J721E
> > +	bool "J721E Cadence DSI wrapper support"
> > +	default y
> > +	help
> > +	  Support J721E Cadence DSI wrapper. The wrapper manages
> > +	  the routing of the DSS DPI signal to the Cadence DSI.
> > +endif
> > diff --git a/drivers/gpu/drm/bridge/cadence/Makefile b/drivers/gpu/drm/bridge/cadence/Makefile
> > index e3d8e9a40784..4cffc8ff71c4 100644
> > --- a/drivers/gpu/drm/bridge/cadence/Makefile
> > +++ b/drivers/gpu/drm/bridge/cadence/Makefile
> > @@ -4,3 +4,4 @@ cdns-mhdp8546-y := cdns-mhdp8546-core.o cdns-mhdp8546-hdcp.o
> >  cdns-mhdp8546-$(CONFIG_DRM_CDNS_MHDP8546_J721E) += cdns-mhdp8546-j721e.o
> >  obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o
> >  cdns-dsi-y := cdns-dsi-core.o
> > +cdns-dsi-$(CONFIG_DRM_CDNS_DSI_J721E) += cdns-dsi-j721e.o
> > diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
> > index cba91247ab26..a5b5dfbf09a0 100644
> > --- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
> > @@ -15,12 +15,16 @@
> >  #include <linux/iopoll.h>
> >  #include <linux/module.h>
> >  #include <linux/of_address.h>
> > +#include <linux/of_device.h>
> >  #include <linux/of_graph.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/pm_runtime.h>
> >  #include <linux/reset.h>
> >  
> >  #include "cdns-dsi-core.h"
> > +#ifdef CONFIG_DRM_CDNS_DSI_J721E
> > +#include "cdns-dsi-j721e.h"
> > +#endif
> >  
> >  static inline struct cdns_dsi *input_to_dsi(struct cdns_dsi_input *input)
> >  {
> > @@ -265,6 +269,10 @@ static void cdns_dsi_bridge_disable(struct drm_bridge *bridge)
> >  
> >  	val = readl(dsi->regs + MCTL_MAIN_EN) & ~IF_EN(input->id);
> >  	writel(val, dsi->regs + MCTL_MAIN_EN);
> > +
> > +	if (dsi->platform_ops && dsi->platform_ops->disable)
> > +		dsi->platform_ops->disable(dsi);
> > +
> >  	pm_runtime_put(dsi->base.dev);
> >  }
> >  
> > @@ -360,6 +368,9 @@ static void cdns_dsi_bridge_enable(struct drm_bridge *bridge)
> >  	if (WARN_ON(pm_runtime_get_sync(dsi->base.dev) < 0))
> >  		return;
> >  
> > +	if (dsi->platform_ops && dsi->platform_ops->enable)
> > +		dsi->platform_ops->enable(dsi);
> > +
> >  	mode = &bridge->encoder->crtc->state->adjusted_mode;
> >  	nlanes = output->dev->lanes;
> >  
> > @@ -800,6 +811,8 @@ static int cdns_dsi_drm_probe(struct platform_device *pdev)
> >  		goto err_disable_pclk;
> >  	}
> >  
> > +	dsi->platform_ops = of_device_get_match_data(&pdev->dev);
> > +
> >  	val = readl(dsi->regs + IP_CONF);
> >  	dsi->direct_cmd_fifo_depth = 1 << (DIRCMD_FIFO_DEPTH(val) + 2);
> >  	dsi->rx_fifo_depth = RX_FIFO_DEPTH(val);
> > @@ -835,14 +848,27 @@ static int cdns_dsi_drm_probe(struct platform_device *pdev)
> >  	dsi->base.dev = &pdev->dev;
> >  	dsi->base.ops = &cdns_dsi_ops;
> >  
> > +	if (dsi->platform_ops && dsi->platform_ops->init) {
> > +		ret = dsi->platform_ops->init(dsi);
> > +		if (ret != 0) {
> > +			dev_err(&pdev->dev, "platform initialization failed: %d\n",
> > +				ret);
> > +			goto err_disable_runtime_pm;
> > +		}
> > +	}
> > +
> >  	ret = mipi_dsi_host_register(&dsi->base);
> >  	if (ret)
> > -		goto err_disable_runtime_pm;
> > +		goto err_deinit_platform;
> >  
> >  	clk_disable_unprepare(dsi->dsi_p_clk);
> >  
> >  	return 0;
> >  
> > +err_deinit_platform:
> > +	if (dsi->platform_ops && dsi->platform_ops->deinit)
> > +		dsi->platform_ops->deinit(dsi);
> > +
> >  err_disable_runtime_pm:
> >  	pm_runtime_disable(&pdev->dev);
> >  
> > @@ -857,6 +883,10 @@ static int cdns_dsi_drm_remove(struct platform_device *pdev)
> >  	struct cdns_dsi *dsi = platform_get_drvdata(pdev);
> >  
> >  	mipi_dsi_host_unregister(&dsi->base);
> > +
> > +	if (dsi->platform_ops && dsi->platform_ops->deinit)
> > +		dsi->platform_ops->deinit(dsi);
> > +
> >  	pm_runtime_disable(&pdev->dev);
> >  
> >  	return 0;
> > @@ -864,6 +894,9 @@ static int cdns_dsi_drm_remove(struct platform_device *pdev)
> >  
> >  static const struct of_device_id cdns_dsi_of_match[] = {
> >  	{ .compatible = "cdns,dsi" },
> > +#ifdef CONFIG_DRM_CDNS_DSI_J721E
> > +	{ .compatible = "ti,j721e-dsi", .data = &dsi_ti_j721e_ops, },
> > +#endif
> >  	{ },
> >  };
> >  MODULE_DEVICE_TABLE(of, cdns_dsi_of_match);
> > diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.h b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.h
> > index 65cc77f19b39..2b1e96440c49 100644
> > --- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.h
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.h
> > @@ -439,9 +439,22 @@ struct cdns_dsi_input {
> >  	struct drm_bridge bridge;
> >  };
> >  
> > +struct cdns_dsi;
> > +
> 
> Please add kerneldoc to document the operations.
> 
> > +struct dsi_platform_ops {
> 
> Call this cdns_dsi_platform_ops, dsi_platform_ops is too generic.
> 
> > +	int (*init)(struct cdns_dsi *dsi);
> > +	void (*deinit)(struct cdns_dsi *dsi);
> > +	void (*enable)(struct cdns_dsi *dsi);
> > +	void (*disable)(struct cdns_dsi *dsi);
> > +};
> > +
> >  struct cdns_dsi {
> >  	struct mipi_dsi_host base;
> >  	void __iomem *regs;
> > +#ifdef CONFIG_DRM_CDNS_DSI_J721E
> > +	void __iomem *j721e_regs;
> > +#endif
> > +	const struct dsi_platform_ops *platform_ops;
> >  	struct cdns_dsi_input input;
> >  	struct cdns_dsi_output output;
> >  	unsigned int direct_cmd_fifo_depth;
> > diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.c
> > new file mode 100644
> > index 000000000000..b5216acb333e
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.c
> > @@ -0,0 +1,51 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * TI j721e Cadence DSI wrapper
> > + *
> > + * Copyright (C) 2022 Texas Instruments Incorporated - http://www.ti.com/
> > + * Author: Rahul T R <r-ravikumar@ti.com>
> > + */
> > +
> > +#include <linux/io.h>
> > +#include <linux/platform_device.h>
> > +
> > +#include "cdns-dsi-j721e.h"
> > +
> > +#define DSI_WRAP_REVISION		0x0
> > +#define DSI_WRAP_DPI_CONTROL		0x4
> > +#define DSI_WRAP_DSC_CONTROL		0x8
> > +#define DSI_WRAP_DPI_SECURE		0xc
> > +#define DSI_WRAP_DSI_0_ASF_STATUS	0x10
> > +
> > +#define DSI_WRAP_DPI_0_EN		BIT(0)
> > +#define DSI_WRAP_DSI2_MUX_SEL		BIT(4)
> > +
> > +static int cdns_dsi_j721e_init(struct cdns_dsi *dsi)
> > +{
> > +	struct platform_device *pdev = to_platform_device(dsi->base.dev);
> > +
> > +	dsi->j721e_regs = devm_platform_ioremap_resource(pdev, 1);
> > +	return PTR_ERR_OR_ZERO(dsi->j721e_regs);
> > +}
> > +
> > +static void cdns_dsi_j721e_enable(struct cdns_dsi *dsi)
> > +{
> > +	/*
> > +	 * Enable DPI0 as its input. DSS0 DPI2 is connected
> > +	 * to DSI DPI0. This is the only supported configuration on
> > +	 * J721E.
> > +	 */
> > +	writel(DSI_WRAP_DPI_0_EN, dsi->j721e_regs + DSI_WRAP_DPI_CONTROL);
> > +}
> > +
> > +static void cdns_dsi_j721e_disable(struct cdns_dsi *dsi)
> > +{
> > +	/* Put everything to defaults  */
> > +	writel(0, dsi->j721e_regs + DSI_WRAP_DPI_CONTROL);
> > +}
> > +
> > +const struct dsi_platform_ops dsi_ti_j721e_ops = {
> > +	.init = cdns_dsi_j721e_init,
> > +	.enable = cdns_dsi_j721e_enable,
> > +	.disable = cdns_dsi_j721e_disable,
> > +};
> > diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.h b/drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.h
> > new file mode 100644
> > index 000000000000..fd251c1a268b
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-j721e.h
> > @@ -0,0 +1,16 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * TI j721e Cadence DSI wrapper
> > + *
> > + * Copyright (C) 2022 Texas Instruments Incorporated - http://www.ti.com/
> > + * Author: Rahul T R <r-ravikumar@ti.com>
> > + */
> > +
> > +#ifndef CDNS_DSI_J721E_H
> 
> __ prefix for header guard ?
> 
> > +#define CDNS_DSI_J721E_H
> > +
> > +#include "cdns-dsi-core.h"
> > +
> > +extern const struct dsi_platform_ops dsi_ti_j721e_ops;
> > +
> > +#endif /* !CDNS_DSI_J721E_H */
> 
> -- 
> Regards,
> 
> Laurent Pinchart

Regards
Rahul T R