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

From: Dmitry Baryshkov
Date: Wed Feb 07 2024 - 05:58:05 EST


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.

> +}
> +
> +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.

> +
> + 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);

> + 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?

> +}
> +
> +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