RE: [PATCH v3 2/2] drm/bridge: cdns-dsi: Add support for StarFive JH7110 SoC

[Shengyang Chen]

Hi, Dmitry

Thanks for review and comment.

> -----Original Message-----
> From: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> Sent: 2024年2月7日 18:58
> To: Shengyang Chen <shengyang.chen@xxxxxxxxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx;
> andrzej.hajda@xxxxxxxxx; neil.armstrong@xxxxxxxxxx; rfoss@xxxxxxxxxx;
> Laurent.pinchart@xxxxxxxxxxxxxxxx; jonas@xxxxxxxxx;
> jernej.skrabec@xxxxxxxxx; maarten.lankhorst@xxxxxxxxxxxxxxx;
> mripard@xxxxxxxxxx; tzimmermann@xxxxxxx; airlied@xxxxxxxxx;
> daniel@xxxxxxxx; robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
> conor+dt@xxxxxxxxxx; p.zabel@xxxxxxxxxxxxxx;
> tomi.valkeinen@xxxxxxxxxxxxxxxx; r-ravikumar@xxxxxx;
> aford173@xxxxxxxxx; agx@xxxxxxxxxxx; rdunlap@xxxxxxxxxxxxx;
> u.kleine-koenig@xxxxxxxxxxxxxx; sam@xxxxxxxxxxxx; bbrezillon@xxxxxxxxxx;
> Changhuang Liang <changhuang.liang@xxxxxxxxxxxxxxxx>; Keith Zhao
> <keith.zhao@xxxxxxxxxxxxxxxx>; Jack Zhu <jack.zhu@xxxxxxxxxxxxxxxx>;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v3 2/2] drm/bridge: cdns-dsi: Add support for StarFive
> JH7110 SoC
> 
> On Tue, 6 Feb 2024 at 08:57, Shengyang Chen
> <shengyang.chen@xxxxxxxxxxxxxxxx> wrote:
> >
> > From: Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx>
> >
> > Add display bridge support for dsi on StarFive JH7110 SoC.
> >
> > The mainly modification is followed:
> >     1.Add extra clock and reset operation for JH7110.
> >     2.Add callback for JH7110.
> >
> > Signed-off-by: Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Shengyang Chen <shengyang.chen@xxxxxxxxxxxxxxxx>
> > ---
> >  drivers/gpu/drm/bridge/cadence/Kconfig        |   7 +
> >  drivers/gpu/drm/bridge/cadence/Makefile       |   1 +
> >  .../gpu/drm/bridge/cadence/cdns-dsi-core.c    |  29 ++-
> >  .../gpu/drm/bridge/cadence/cdns-dsi-core.h    |  21 ++
> >  .../gpu/drm/bridge/cadence/cdns-dsi-jh7110.c  | 193
> > ++++++++++++++++++  .../gpu/drm/bridge/cadence/cdns-dsi-jh7110.h  |
> > 16 ++
> >  6 files changed, 266 insertions(+), 1 deletion(-)  create mode 100644
> > drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.c
> >  create mode 100644 drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.h
> >
> > diff --git a/drivers/gpu/drm/bridge/cadence/Kconfig
> > b/drivers/gpu/drm/bridge/cadence/Kconfig
> > index cced81633ddc..ad9f572f4720 100644
> > --- a/drivers/gpu/drm/bridge/cadence/Kconfig
> > +++ b/drivers/gpu/drm/bridge/cadence/Kconfig
> > @@ -19,6 +19,13 @@ config DRM_CDNS_DSI_J721E
> >         help
> >           Support J721E Cadence DSI wrapper. The wrapper manages
> >           the routing of the DSS DPI signal to the Cadence DSI.
> > +
> > +config DRM_CDNS_DSI_JH7110
> > +       bool "JH7110 SOC Cadence DSI support"
> > +       default n
> > +       help
> > +         Cadence DPI to DSI bridge which is embedded in the
> > +         StarFive JH7110 SoC.
> >  endif
> >
> >  config DRM_CDNS_MHDP8546
> > diff --git a/drivers/gpu/drm/bridge/cadence/Makefile
> > b/drivers/gpu/drm/bridge/cadence/Makefile
> > index c95fd5b81d13..87f603a9f4ad 100644
> > --- a/drivers/gpu/drm/bridge/cadence/Makefile
> > +++ b/drivers/gpu/drm/bridge/cadence/Makefile
> > @@ -2,6 +2,7 @@
> >  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
> > +cdns-dsi-$(CONFIG_DRM_CDNS_DSI_JH7110) += cdns-dsi-jh7110.o
> >  obj-$(CONFIG_DRM_CDNS_MHDP8546) += cdns-mhdp8546.o
> cdns-mhdp8546-y
> > := cdns-mhdp8546-core.o cdns-mhdp8546-hdcp.o
> >  cdns-mhdp8546-$(CONFIG_DRM_CDNS_MHDP8546_J721E) +=
> > cdns-mhdp8546-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 7457d38622b0..c0c81745e765 100644
> > --- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
> > @@ -27,6 +27,10 @@
> >  #include "cdns-dsi-j721e.h"
> >  #endif
> >
> > +#ifdef CONFIG_DRM_CDNS_DSI_JH7110
> > +#include "cdns-dsi-jh7110.h"
> > +#endif
> > +
> >  #define IP_CONF                                0x0
> >  #define SP_HS_FIFO_DEPTH(x)            (((x) & GENMASK(30, 26)) >>
> 26)
> >  #define SP_LP_FIFO_DEPTH(x)            (((x) & GENMASK(25, 21)) >>
> 21)
> > @@ -552,6 +556,10 @@ static int cdns_dsi_adjust_phy_config(struct cdns_dsi
> *dsi,
> >         /* data rate was in bytes/sec, convert to bits/sec. */
> >         phy_cfg->hs_clk_rate = dlane_bps * 8;
> >
> > +       if (dsi->platform_ops && dsi->platform_ops->mode_fixup)
> > +               adj_dsi_htotal = dsi->platform_ops->mode_fixup(dsi,
> dsi_cfg, phy_cfg,
> > +
> dpi_hz,
> > + dpi_htotal, dsi_htotal);
> > +
> >         dsi_hfp_ext = adj_dsi_htotal - dsi_htotal;
> >         dsi_cfg->hfp += dsi_hfp_ext;
> >         dsi_cfg->htotal = dsi_htotal + dsi_hfp_ext; @@ -683,7 +691,7
> > @@ static void cdns_dsi_bridge_post_disable(struct drm_bridge *bridge)
> >         pm_runtime_put(dsi->base.dev);  }
> >
> > -static void cdns_dsi_hs_init(struct cdns_dsi *dsi)
> > +void cdns_dsi_hs_init(struct cdns_dsi *dsi)
> >  {
> >         struct cdns_dsi_output *output = &dsi->output;
> >         u32 status;
> > @@ -1026,6 +1034,14 @@ static ssize_t cdns_dsi_transfer(struct
> > mipi_dsi_host *host,
> >
> >         cdns_dsi_init_link(dsi);
> >
> > +       /*
> > +        * on JH7110 SoC , when transfer dsi command ,
> > +        * cdns_dsi_hs_init is needed.
> > +        * or the final ret will be error value.
> > +        */
> > +       if (dsi->platform_ops && dsi->platform_ops->transfer)
> > +               dsi->platform_ops->transfer(dsi);
> > +
> >         ret = mipi_dsi_create_packet(&packet, msg);
> >         if (ret)
> >                 goto out;
> > @@ -1142,6 +1158,9 @@ static int __maybe_unused cdns_dsi_resume(struct
> device *dev)
> >         clk_prepare_enable(dsi->dsi_p_clk);
> >         clk_prepare_enable(dsi->dsi_sys_clk);
> >
> > +       if (dsi->platform_ops && dsi->platform_ops->resume)
> > +               dsi->platform_ops->resume(dsi);
> > +
> >         return 0;
> >  }
> >
> > @@ -1152,6 +1171,10 @@ static int __maybe_unused
> cdns_dsi_suspend(struct device *dev)
> >         clk_disable_unprepare(dsi->dsi_sys_clk);
> >         clk_disable_unprepare(dsi->dsi_p_clk);
> >         reset_control_assert(dsi->dsi_p_rst);
> > +
> > +       if (dsi->platform_ops && dsi->platform_ops->suspend)
> > +               dsi->platform_ops->suspend(dsi);
> > +
> >         dsi->link_initialized = false;
> >         return 0;
> >  }
> > @@ -1294,6 +1317,10 @@ static const struct of_device_id
> > cdns_dsi_of_match[] = {  #ifdef CONFIG_DRM_CDNS_DSI_J721E
> >         { .compatible = "ti,j721e-dsi", .data = &dsi_ti_j721e_ops, },
> > #endif
> > +#ifdef CONFIG_DRM_CDNS_DSI_JH7110
> > +       { .compatible = "starfive,jh7110-dsi", .data =
> > +&dsi_ti_jh7110_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 ca7ea2da635c..0a86495ead7b 100644
> > --- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.h
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.h
> > @@ -53,12 +53,22 @@ struct cdns_dsi;
> >   * @deinit: Called in the CDNS DSI remove
> >   * @enable: Called at the beginning of CDNS DSI bridge enable
> >   * @disable: Called at the end of CDNS DSI bridge disable
> > + * @resume: Called at the resume of CDNS DSI
> > + * @suspend: Called at the suspend of CDNS DSI
> > + * @update: Called at the middle of CDNS DSI bridge enable
> >   */
> >  struct cdns_dsi_platform_ops {
> >         int (*init)(struct cdns_dsi *dsi);
> >         void (*deinit)(struct cdns_dsi *dsi);
> >         void (*enable)(struct cdns_dsi *dsi);
> >         void (*disable)(struct cdns_dsi *dsi);
> > +       void (*resume)(struct cdns_dsi *dsi);
> > +       void (*suspend)(struct cdns_dsi *dsi);
> > +       int (*mode_fixup)(struct cdns_dsi *dsi, struct cdns_dsi_cfg *dsi_cfg,
> > +                         struct phy_configure_opts_mipi_dphy
> *phy_cfg,
> > +                         unsigned long dpi_hz, unsigned long
> dpi_htotal,
> > +                         unsigned long dsi_htotal);
> > +       void (*transfer)(struct cdns_dsi *dsi);
> >  };
> >
> >  struct cdns_dsi {
> > @@ -79,6 +89,17 @@ struct cdns_dsi {
> >         bool link_initialized;
> >         bool phy_initialized;
> >         struct phy *dphy;
> > +
> > +#ifdef CONFIG_DRM_CDNS_DSI_JH7110
> > +       struct clk *dpi_clk;
> > +       struct clk *txesc_clk;
> > +       struct reset_control *dpi_rst;
> > +       struct reset_control *sys_rst;
> > +       struct reset_control *txesc_rst;
> > +       struct reset_control *txbytehs_rst; #endif
> >  };
> >
> > +void cdns_dsi_hs_init(struct cdns_dsi *dsi);
> > +
> >  #endif /* !__CDNS_DSI_H__ */
> > diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.c
> > b/drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.c
> > new file mode 100644
> > index 000000000000..c6b9296a9275
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.c
> > @@ -0,0 +1,193 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * JH7110 SoC Cadence DSI wrapper
> > + *
> > + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/io.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/reset.h>
> > +
> > +#include "cdns-dsi-jh7110.h"
> > +
> > +static int cdns_dsi_clock_enable(struct cdns_dsi *dsi, struct device
> > +*dev) {
> > +       int ret;
> > +
> > +       ret = clk_prepare_enable(dsi->dpi_clk);
> > +       if (ret) {
> > +               dev_err(dev, "Failed to prepare/enable dpi_clk\n");
> > +               return ret;
> > +       }
> > +
> > +       ret = clk_prepare_enable(dsi->txesc_clk);
> > +       if (ret) {
> > +               dev_err(dev, "Failed to prepare/enable txesc_clk\n");
> > +               return ret;
> > +       }
> > +
> > +       return ret;
> > +}
> > +
> > +static void cdns_dsi_clock_disable(struct cdns_dsi *dsi) {
> > +       clk_disable_unprepare(dsi->dpi_clk);
> > +       clk_disable_unprepare(dsi->txesc_clk);
> 
> Please use clk_bulk_ API and inline these two functions.
> 

ok, will follow up this issue.

> > +}
> > +
> > +static int cdns_dsi_resets_deassert(struct cdns_dsi *dsi, struct
> > +device *dev) {
> > +       int ret;
> > +
> > +       ret = reset_control_deassert(dsi->dpi_rst);
> > +       if (ret < 0) {
> > +               dev_err(dev, "failed to deassert dpi_rst\n");
> > +               return ret;
> > +       }
> > +
> > +       ret = reset_control_deassert(dsi->txesc_rst);
> > +       if (ret < 0) {
> > +               dev_err(dev, "failed to deassert txesc_rst\n");
> > +               return ret;
> > +       }
> > +
> > +       ret = reset_control_deassert(dsi->sys_rst);
> > +       if (ret < 0) {
> > +               dev_err(dev, "failed to deassert sys_rst\n");
> > +               return ret;
> > +       }
> 
> Same, please use reset_control_bulk API.
> 

ok, will follow up this issue.

> > +
> > +       return ret;
> > +}
> > +
> > +static int cdns_dsi_resets_assert(struct cdns_dsi *dsi, struct device
> > +*dev) {
> > +       int ret;
> > +
> > +       ret = reset_control_assert(dsi->dpi_rst);
> > +       if (ret < 0) {
> > +               dev_err(dev, "failed to assert dpi_rst\n");
> > +               return ret;
> > +       }
> > +
> > +       ret = reset_control_assert(dsi->txesc_rst);
> > +       if (ret < 0) {
> > +               dev_err(dev, "failed to assert txesc_rst\n");
> > +               return ret;
> > +       }
> > +
> > +       ret = reset_control_assert(dsi->sys_rst);
> > +       if (ret < 0) {
> > +               dev_err(dev, "failed to assert sys_rst\n");
> > +               return ret;
> > +       }
> > +
> > +       return ret;
> > +}
> > +
> > +static int cdns_dsi_get_clock(struct device *dev, struct cdns_dsi
> > +*dsi) {
> > +       dsi->dpi_clk = devm_clk_get(dev, "dpi");
> > +       if (IS_ERR(dsi->dpi_clk))
> > +               return PTR_ERR(dsi->dpi_clk);
> > +
> > +       dsi->txesc_clk = devm_clk_get(dev, "txesc");
> > +       if (IS_ERR(dsi->txesc_clk))
> > +               return PTR_ERR(dsi->txesc_clk);
> > +
> > +       return 0;
> > +}
> > +
> > +static int cdns_dsi_get_reset(struct device *dev, struct cdns_dsi
> > +*dsi) {
> > +       dsi->sys_rst = devm_reset_control_get_exclusive(dev, "sys");
> > +       if (IS_ERR(dsi->sys_rst))
> > +               return PTR_ERR(dsi->sys_rst);
> > +
> > +       dsi->dpi_rst = devm_reset_control_get_exclusive(dev, "dpi");
> > +       if (IS_ERR(dsi->dpi_rst))
> > +               return PTR_ERR(dsi->dpi_rst);
> > +
> > +       dsi->txesc_rst = devm_reset_control_get_exclusive(dev, "txesc");
> > +       if (IS_ERR(dsi->txesc_rst))
> > +               return PTR_ERR(dsi->txesc_rst);
> > +
> > +       dsi->txbytehs_rst = devm_reset_control_get_exclusive(dev,
> "txbytehs");
> > +       if (IS_ERR(dsi->txbytehs_rst))
> > +               return PTR_ERR(dsi->txbytehs_rst);
> > +
> > +       return 0;
> > +}
> > +
> > +static int cdns_dsi_jh7110_init(struct cdns_dsi *dsi) {
> > +       int ret;
> > +
> > +       ret = cdns_dsi_get_clock(dsi->base.dev, dsi);
> > +       if (ret)
> > +               return ret;
> > +
> > +       return cdns_dsi_get_reset(dsi->base.dev, dsi); }
> > +
> > +static void cdns_dsi_jh7110_resume(struct cdns_dsi *dsi) {
> > +       int ret;
> > +
> > +       ret = cdns_dsi_clock_enable(dsi, dsi->base.dev);
> > +       if (ret) {
> > +               dev_err(dsi->base.dev, "failed to enable clock\n");
> > +               return;
> > +       }
> > +       ret = cdns_dsi_resets_deassert(dsi, dsi->base.dev);
> > +       if (ret < 0) {
> > +               dev_err(dsi->base.dev, "failed to deassert reset\n");
> > +               return;
> > +       }
> > +}
> > +
> > +static void cdns_dsi_jh7110_suspend(struct cdns_dsi *dsi) {
> > +       int ret;
> > +
> > +       ret = cdns_dsi_resets_assert(dsi, dsi->base.dev);
> > +       if (ret < 0) {
> > +               dev_err(dsi->base.dev, "failed to deassert reset\n");
> > +               return;
> > +       }
> > +
> > +       cdns_dsi_clock_disable(dsi);
> > +}
> > +
> > +static int cdns_dsi_jh7110_mode_fixup(struct cdns_dsi *dsi, struct
> cdns_dsi_cfg *dsi_cfg,
> > +                                     struct
> phy_configure_opts_mipi_dphy *phy_cfg,
> > +                                     unsigned long dpi_hz, unsigned
> long dpi_htotal,
> > +                                     unsigned long dsi_htotal) {
> > +       unsigned long long dlane_bps;
> > +       unsigned long adj_dsi_htotal;
> > +       unsigned int lanes = dsi->output.dev->lanes;
> > +
> > +       phy_cfg->hs_clk_rate = phy_cfg->hs_clk_rate -
> (phy_cfg->hs_clk_rate % 10000000);
> > +       phy_cfg->hs_clk_rate += 100000000;
> 
> phy_cfg->hs_clk_rate = roundup(phy_cfg->hs_clk_rate, 100000000);
> 

ok, will fix it
thanks for suggestion.

> > +       dlane_bps = phy_cfg->hs_clk_rate * lanes * dpi_htotal / 8;
> > +       adj_dsi_htotal = dlane_bps / dpi_hz;
> > +
> > +       return adj_dsi_htotal;
> > +}
> > +
> > +static void jh7110_cdns_dsi_hs_init(struct cdns_dsi *dsi) {
> > +       cdns_dsi_hs_init(dsi);
> > +       reset_control_deassert(dsi->txbytehs_rst);
> 
> Is a single deassert enough here? Which funciion asserts the reset?
> 

will follow up this issue
We verified that we may add assert in our rpm suspend API in next version.
thanks for mention

> > +}
> > +
> > +const struct cdns_dsi_platform_ops dsi_ti_jh7110_ops = {
> > +       .init = cdns_dsi_jh7110_init,
> > +       .resume = cdns_dsi_jh7110_resume,
> > +       .suspend = cdns_dsi_jh7110_suspend,
> > +       .mode_fixup = cdns_dsi_jh7110_mode_fixup,
> > +       .transfer = jh7110_cdns_dsi_hs_init, };
> > diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.h
> > b/drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.h
> > new file mode 100644
> > index 000000000000..15d6a766b502
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-jh7110.h
> > @@ -0,0 +1,16 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * JH7110 Cadence DSI
> > + *
> > + * Copyright (C) 2022-2023 StarFive Technology Co., Ltd.
> > + * Author: keith.zhao <keith.zhao@xxxxxxxxxxxxxxxx>  */
> > +
> > +#ifndef __CDNS_DSI_JH7110_H__
> > +#define __CDNS_DSI_JH7110_H__
> > +
> > +#include "cdns-dsi-core.h"
> > +
> > +extern const struct cdns_dsi_platform_ops dsi_ti_jh7110_ops;
> > +
> > +#endif /* !__CDNS_DSI_JH7110_H__ */
> > --
> > 2.17.1
> >
> 
> 
> --
> With best wishes
> Dmitry


thanks.

Best Regards,
Shengyang