Re: [PATCH 2/2] drm: bridge: cdns-mhdp8546: Enable HDCP

[Robert Foss]

Hey Parshuram,

This patch looks good to me.
Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>

On Fri, 26 Feb 2021 at 17:18, Parshuram Thombare <pthombar@xxxxxxxxxxx> wrote:
>
> This patch enable HDCP in MHDP driver.
>
> Signed-off-by: Parshuram Thombare <pthombar@xxxxxxxxxxx>
> ---
>  drivers/gpu/drm/bridge/cadence/Makefile       |   2 +-
>  .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 105 +++-
>  .../drm/bridge/cadence/cdns-mhdp8546-core.h   |  21 +
>  .../drm/bridge/cadence/cdns-mhdp8546-hdcp.c   | 578 ++++++++++++++++++
>  .../drm/bridge/cadence/cdns-mhdp8546-hdcp.h   |  89 +++
>  5 files changed, 782 insertions(+), 13 deletions(-)
>  create mode 100644 drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c
>  create mode 100644 drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.h
>
> diff --git a/drivers/gpu/drm/bridge/cadence/Makefile b/drivers/gpu/drm/bridge/cadence/Makefile
> index 8f647991b374..4d2db8df1bc6 100644
> --- a/drivers/gpu/drm/bridge/cadence/Makefile
> +++ b/drivers/gpu/drm/bridge/cadence/Makefile
> @@ -1,4 +1,4 @@
>  # SPDX-License-Identifier: GPL-2.0-only
>  obj-$(CONFIG_DRM_CDNS_MHDP8546) += cdns-mhdp8546.o
> -cdns-mhdp8546-y := cdns-mhdp8546-core.o
> +cdns-mhdp8546-y := cdns-mhdp8546-core.o cdns-mhdp8546-hdcp.o
>  cdns-mhdp8546-$(CONFIG_DRM_CDNS_MHDP8546_J721E) += cdns-mhdp8546-j721e.o
> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> index d0c65610ebb5..e2d75fc596f6 100644
> --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> @@ -42,6 +42,7 @@
>  #include <drm/drm_connector.h>
>  #include <drm/drm_crtc_helper.h>
>  #include <drm/drm_dp_helper.h>
> +#include <drm/drm_hdcp.h>
>  #include <drm/drm_modeset_helper_vtables.h>
>  #include <drm/drm_print.h>
>  #include <drm/drm_probe_helper.h>
> @@ -49,7 +50,7 @@
>  #include <asm/unaligned.h>
>
>  #include "cdns-mhdp8546-core.h"
> -
> +#include "cdns-mhdp8546-hdcp.h"
>  #include "cdns-mhdp8546-j721e.h"
>
>  static int cdns_mhdp_mailbox_read(struct cdns_mhdp_device *mhdp)
> @@ -1614,10 +1615,40 @@ enum drm_mode_status cdns_mhdp_mode_valid(struct drm_connector *conn,
>         return MODE_OK;
>  }
>
> +static int cdns_mhdp_connector_atomic_check(struct drm_connector *conn,
> +                                           struct drm_atomic_state *state)
> +{
> +       struct drm_connector_state *old_state, *new_state;
> +       struct drm_crtc_state *crtc_state;
> +       u64 old_cp, new_cp;
> +
> +       old_state = drm_atomic_get_old_connector_state(state, conn);
> +       new_state = drm_atomic_get_new_connector_state(state, conn);
> +       old_cp = old_state->content_protection;
> +       new_cp = new_state->content_protection;
> +
> +       if (!new_state->crtc) {
> +               if (old_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED)
> +                       new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
> +               return 0;
> +       }
> +
> +       if (old_cp == new_cp ||
> +           (old_cp == DRM_MODE_CONTENT_PROTECTION_DESIRED &&
> +            new_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED))
> +               return 0;
> +
> +       crtc_state = drm_atomic_get_new_crtc_state(state, new_state->crtc);
> +       crtc_state->mode_changed = true;
> +
> +       return 0;
> +}
> +
>  static const struct drm_connector_helper_funcs cdns_mhdp_conn_helper_funcs = {
>         .detect_ctx = cdns_mhdp_connector_detect,
>         .get_modes = cdns_mhdp_get_modes,
>         .mode_valid = cdns_mhdp_mode_valid,
> +       .atomic_check = cdns_mhdp_connector_atomic_check,
>  };
>
>  static const struct drm_connector_funcs cdns_mhdp_conn_funcs = {
> @@ -1662,7 +1693,7 @@ static int cdns_mhdp_connector_init(struct cdns_mhdp_device *mhdp)
>                 return ret;
>         }
>
> -       return 0;
> +       return drm_connector_attach_content_protection_property(conn, true);
>  }
>
>  static int cdns_mhdp_attach(struct drm_bridge *bridge,
> @@ -1956,6 +1987,13 @@ static void cdns_mhdp_atomic_enable(struct drm_bridge *bridge,
>         conn_state = drm_atomic_get_new_connector_state(state, connector);
>         if (WARN_ON(!conn_state))
>                 goto out;
> +       if (conn_state->content_protection ==
> +           DRM_MODE_CONTENT_PROTECTION_DESIRED &&
> +           mhdp->hw_state == MHDP_HW_READY) {
> +               mutex_unlock(&mhdp->link_mutex);
> +               cdns_mhdp_hdcp_enable(mhdp);
> +               mutex_lock(&mhdp->link_mutex);
> +       }
>
>         crtc_state = drm_atomic_get_new_crtc_state(state, conn_state->crtc);
>         if (WARN_ON(!crtc_state))
> @@ -2000,6 +2038,7 @@ static void cdns_mhdp_atomic_disable(struct drm_bridge *bridge,
>
>         mutex_lock(&mhdp->link_mutex);
>
> +       cdns_mhdp_hdcp_disable(mhdp);
>         mhdp->bridge_enabled = false;
>         cdns_mhdp_reg_read(mhdp, CDNS_DP_FRAMER_GLOBAL_CONFIG, &resp);
>         resp &= ~CDNS_DP_FRAMER_EN;
> @@ -2288,7 +2327,6 @@ static irqreturn_t cdns_mhdp_irq_handler(int irq, void *data)
>         struct cdns_mhdp_device *mhdp = data;
>         u32 apb_stat, sw_ev0;
>         bool bridge_attached;
> -       int ret;
>
>         apb_stat = readl(mhdp->regs + CDNS_APB_INT_STATUS);
>         if (!(apb_stat & CDNS_APB_INT_MASK_SW_EVENT_INT))
> @@ -2307,20 +2345,54 @@ static irqreturn_t cdns_mhdp_irq_handler(int irq, void *data)
>         spin_unlock(&mhdp->start_lock);
>
>         if (bridge_attached && (sw_ev0 & CDNS_DPTX_HPD)) {
> -               ret = cdns_mhdp_update_link_status(mhdp);
> -               if (mhdp->connector.dev) {
> -                       if (ret < 0)
> -                               schedule_work(&mhdp->modeset_retry_work);
> -                       else
> -                               drm_kms_helper_hotplug_event(mhdp->bridge.dev);
> -               } else {
> -                       drm_bridge_hpd_notify(&mhdp->bridge, cdns_mhdp_detect(mhdp));
> -               }
> +               schedule_work(&mhdp->hpd_work);
> +       }
> +
> +       if (sw_ev0 & ~CDNS_DPTX_HPD) {
> +               mhdp->sw_events |= (sw_ev0 & ~CDNS_DPTX_HPD);
> +               wake_up(&mhdp->sw_events_wq);
>         }
>
>         return IRQ_HANDLED;
>  }
>
> +u32 cdns_mhdp_wait_for_sw_event(struct cdns_mhdp_device *mhdp, u32 event)
> +{
> +       u32 ret;
> +
> +       ret = wait_event_timeout(mhdp->sw_events_wq,
> +                                mhdp->sw_events & event,
> +                                msecs_to_jiffies(500));
> +       if (!ret) {
> +               dev_dbg(mhdp->dev, "SW event 0x%x timeout\n", event);
> +               goto sw_event_out;
> +       }
> +
> +       ret = mhdp->sw_events;
> +       mhdp->sw_events &= ~event;
> +
> +sw_event_out:
> +       return ret;
> +}
> +
> +static void cdns_mhdp_hpd_work(struct work_struct *work)
> +{
> +       struct cdns_mhdp_device *mhdp = container_of(work,
> +                                                    struct cdns_mhdp_device,
> +                                                    hpd_work);
> +       int ret;
> +
> +       ret = cdns_mhdp_update_link_status(mhdp);
> +       if (mhdp->connector.dev) {
> +               if (ret < 0)
> +                       schedule_work(&mhdp->modeset_retry_work);
> +               else
> +                       drm_kms_helper_hotplug_event(mhdp->bridge.dev);
> +       } else {
> +               drm_bridge_hpd_notify(&mhdp->bridge, cdns_mhdp_detect(mhdp));
> +       }
> +}
> +
>  static int cdns_mhdp_probe(struct platform_device *pdev)
>  {
>         struct device *dev = &pdev->dev;
> @@ -2356,6 +2428,12 @@ static int cdns_mhdp_probe(struct platform_device *pdev)
>                 return PTR_ERR(mhdp->regs);
>         }
>
> +       mhdp->sapb_regs = devm_platform_ioremap_resource(pdev, 2);
> +       if (IS_ERR(mhdp->sapb_regs)) {
> +               dev_err(dev, "Failed to get SAPB memory resource\n");
> +               return PTR_ERR(mhdp->sapb_regs);
> +       }
> +
>         mhdp->phy = devm_of_phy_get_by_index(dev, pdev->dev.of_node, 0);
>         if (IS_ERR(mhdp->phy)) {
>                 dev_err(dev, "no PHY configured\n");
> @@ -2430,13 +2508,16 @@ static int cdns_mhdp_probe(struct platform_device *pdev)
>
>         /* Initialize the work for modeset in case of link train failure */
>         INIT_WORK(&mhdp->modeset_retry_work, cdns_mhdp_modeset_retry_fn);
> +       INIT_WORK(&mhdp->hpd_work, cdns_mhdp_hpd_work);
>
>         init_waitqueue_head(&mhdp->fw_load_wq);
> +       init_waitqueue_head(&mhdp->sw_events_wq);
>
>         ret = cdns_mhdp_load_firmware(mhdp);
>         if (ret)
>                 goto phy_exit;
>
> +       cdns_mhdp_hdcp_init(mhdp, pdev->dev.of_node);
>         drm_bridge_add(&mhdp->bridge);
>
>         return 0;
> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h
> index 5897a85e3159..0d652569e487 100644
> --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h
> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h
> @@ -47,6 +47,10 @@ struct phy;
>
>  #define CDNS_SW_EVENT0                         0x00044
>  #define CDNS_DPTX_HPD                          BIT(0)
> +#define CDNS_HDCP_TX_STATUS                    BIT(4)
> +#define CDNS_HDCP2_TX_IS_KM_STORED             BIT(5)
> +#define CDNS_HDCP2_TX_STORE_KM                 BIT(6)
> +#define CDNS_HDCP_TX_IS_RCVR_ID_VALID          BIT(7)
>
>  #define CDNS_SW_EVENT1                         0x00048
>  #define CDNS_SW_EVENT2                         0x0004c
> @@ -339,8 +343,17 @@ struct cdns_mhdp_platform_info {
>  #define to_cdns_mhdp_bridge_state(s) \
>                 container_of(s, struct cdns_mhdp_bridge_state, base)
>
> +struct cdns_mhdp_hdcp {
> +       struct delayed_work check_work;
> +       struct work_struct prop_work;
> +       struct mutex mutex; /* mutex to protect hdcp.value */
> +       u32 value;
> +       u8 config;
> +};
> +
>  struct cdns_mhdp_device {
>         void __iomem *regs;
> +       void __iomem *sapb_regs;
>         void __iomem *j721e_regs;
>
>         struct device *dev;
> @@ -392,9 +405,17 @@ struct cdns_mhdp_device {
>
>         /* Work struct to schedule a uevent on link train failure */
>         struct work_struct modeset_retry_work;
> +       struct work_struct hpd_work;
> +
> +       wait_queue_head_t sw_events_wq;
> +       u32 sw_events;
> +
> +       struct cdns_mhdp_hdcp hdcp;
>  };
>
>  #define connector_to_mhdp(x) container_of(x, struct cdns_mhdp_device, connector)
>  #define bridge_to_mhdp(x) container_of(x, struct cdns_mhdp_device, bridge)
>
> +u32 cdns_mhdp_wait_for_sw_event(struct cdns_mhdp_device *mhdp, uint32_t event);
> +
>  #endif
> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c
> new file mode 100644
> index 000000000000..c0ee8235ffa9
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c
> @@ -0,0 +1,578 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Cadence MHDP8546 DP bridge driver.
> + *
> + * Copyright (C) 2020 Cadence Design Systems, Inc.
> + *
> + */
> +
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +
> +#include <asm/unaligned.h>
> +
> +#include "cdns-mhdp8546-hdcp.h"
> +
> +static int cdns_mhdp_secure_mailbox_read(struct cdns_mhdp_device *mhdp)
> +{
> +       int ret, empty;
> +
> +       WARN_ON(!mutex_is_locked(&mhdp->mbox_mutex));
> +
> +       ret = readx_poll_timeout(readl, mhdp->sapb_regs + CDNS_MAILBOX_EMPTY,
> +                                empty, !empty, MAILBOX_RETRY_US,
> +                                MAILBOX_TIMEOUT_US);
> +       if (ret < 0)
> +               return ret;
> +
> +       return readl(mhdp->sapb_regs + CDNS_MAILBOX_RX_DATA) & 0xff;
> +}
> +
> +static int cdns_mhdp_secure_mailbox_write(struct cdns_mhdp_device *mhdp,
> +                                         u8 val)
> +{
> +       int ret, full;
> +
> +       WARN_ON(!mutex_is_locked(&mhdp->mbox_mutex));
> +
> +       ret = readx_poll_timeout(readl, mhdp->sapb_regs + CDNS_MAILBOX_FULL,
> +                                full, !full, MAILBOX_RETRY_US,
> +                                MAILBOX_TIMEOUT_US);
> +       if (ret < 0)
> +               return ret;
> +
> +       writel(val, mhdp->sapb_regs + CDNS_MAILBOX_TX_DATA);
> +
> +       return 0;
> +}
> +
> +static int cdns_mhdp_secure_mailbox_recv_header(struct cdns_mhdp_device *mhdp,
> +                                               u8 module_id,
> +                                               u8 opcode,
> +                                               u16 req_size)
> +{
> +       u32 mbox_size, i;
> +       u8 header[4];
> +       int ret;
> +
> +       /* read the header of the message */
> +       for (i = 0; i < sizeof(header); i++) {
> +               ret = cdns_mhdp_secure_mailbox_read(mhdp);
> +               if (ret < 0)
> +                       return ret;
> +
> +               header[i] = ret;
> +       }
> +
> +       mbox_size = get_unaligned_be16(header + 2);
> +
> +       if (opcode != header[0] || module_id != header[1] ||
> +           (opcode != HDCP_TRAN_IS_REC_ID_VALID && req_size != mbox_size)) {
> +               for (i = 0; i < mbox_size; i++)
> +                       if (cdns_mhdp_secure_mailbox_read(mhdp) < 0)
> +                               break;
> +               return -EINVAL;
> +       }
> +
> +       return 0;
> +}
> +
> +static int cdns_mhdp_secure_mailbox_recv_data(struct cdns_mhdp_device *mhdp,
> +                                             u8 *buff, u16 buff_size)
> +{
> +       int ret;
> +       u32 i;
> +
> +       for (i = 0; i < buff_size; i++) {
> +               ret = cdns_mhdp_secure_mailbox_read(mhdp);
> +               if (ret < 0)
> +                       return ret;
> +
> +               buff[i] = ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static int cdns_mhdp_secure_mailbox_send(struct cdns_mhdp_device *mhdp,
> +                                        u8 module_id,
> +                                        u8 opcode,
> +                                        u16 size,
> +                                        u8 *message)
> +{
> +       u8 header[4];
> +       int ret;
> +       u32 i;
> +
> +       header[0] = opcode;
> +       header[1] = module_id;
> +       put_unaligned_be16(size, header + 2);
> +
> +       for (i = 0; i < sizeof(header); i++) {
> +               ret = cdns_mhdp_secure_mailbox_write(mhdp, header[i]);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       for (i = 0; i < size; i++) {
> +               ret = cdns_mhdp_secure_mailbox_write(mhdp, message[i]);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static int cdns_mhdp_hdcp_get_status(struct cdns_mhdp_device *mhdp,
> +                                    u16 *hdcp_port_status)
> +{
> +       u8 hdcp_status[HDCP_STATUS_SIZE];
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                           HDCP_TRAN_STATUS_CHANGE, 0, NULL);
> +       if (ret)
> +               goto err_get_hdcp_status;
> +
> +       ret = cdns_mhdp_secure_mailbox_recv_header(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                                  HDCP_TRAN_STATUS_CHANGE,
> +                                                  sizeof(hdcp_status));
> +       if (ret)
> +               goto err_get_hdcp_status;
> +
> +       ret = cdns_mhdp_secure_mailbox_recv_data(mhdp, hdcp_status,
> +                                                sizeof(hdcp_status));
> +       if (ret)
> +               goto err_get_hdcp_status;
> +
> +       *hdcp_port_status = ((u16)(hdcp_status[0] << 8) | hdcp_status[1]);
> +
> +err_get_hdcp_status:
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +static u8 cdns_mhdp_hdcp_handle_status(struct cdns_mhdp_device *mhdp,
> +                                      u16 status)
> +{
> +       u8 err = GET_HDCP_PORT_STS_LAST_ERR(status);
> +
> +       if (err)
> +               dev_dbg(mhdp->dev, "HDCP Error = %d", err);
> +
> +       return err;
> +}
> +
> +static int cdns_mhdp_hdcp_rx_id_valid_response(struct cdns_mhdp_device *mhdp,
> +                                              u8 valid)
> +{
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                           HDCP_TRAN_RESPOND_RECEIVER_ID_VALID,
> +                                           1, &valid);
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +static int cdns_mhdp_hdcp_rx_id_valid(struct cdns_mhdp_device *mhdp,
> +                                     u8 *recv_num, u8 *hdcp_rx_id)
> +{
> +       u8 rec_id_hdr[2];
> +       u8 status;
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                           HDCP_TRAN_IS_REC_ID_VALID, 0, NULL);
> +       if (ret)
> +               goto err_rx_id_valid;
> +
> +       ret = cdns_mhdp_secure_mailbox_recv_header(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                                  HDCP_TRAN_IS_REC_ID_VALID,
> +                                                  sizeof(status));
> +       if (ret)
> +               goto err_rx_id_valid;
> +
> +       ret = cdns_mhdp_secure_mailbox_recv_data(mhdp, rec_id_hdr, 2);
> +       if (ret)
> +               goto err_rx_id_valid;
> +
> +       *recv_num = rec_id_hdr[0];
> +
> +       ret = cdns_mhdp_secure_mailbox_recv_data(mhdp, hdcp_rx_id, 5 * *recv_num);
> +
> +err_rx_id_valid:
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +static int cdns_mhdp_hdcp_km_stored_resp(struct cdns_mhdp_device *mhdp,
> +                                        u32 size, u8 *km)
> +{
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                           HDCP2X_TX_RESPOND_KM, size, km);
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +static int cdns_mhdp_hdcp_tx_is_km_stored(struct cdns_mhdp_device *mhdp,
> +                                         u8 *resp, u32 size)
> +{
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                           HDCP2X_TX_IS_KM_STORED, 0, NULL);
> +       if (ret)
> +               goto err_is_km_stored;
> +
> +       ret = cdns_mhdp_secure_mailbox_recv_header(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                                  HDCP2X_TX_IS_KM_STORED,
> +                                                  size);
> +       if (ret)
> +               goto err_is_km_stored;
> +
> +       ret = cdns_mhdp_secure_mailbox_recv_data(mhdp, resp, size);
> +err_is_km_stored:
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +static int cdns_mhdp_hdcp_tx_config(struct cdns_mhdp_device *mhdp,
> +                                   u8 hdcp_cfg)
> +{
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                           HDCP_TRAN_CONFIGURATION, 1, &hdcp_cfg);
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +static int cdns_mhdp_hdcp_set_config(struct cdns_mhdp_device *mhdp,
> +                                    u8 hdcp_config, bool enable)
> +{
> +       u16 hdcp_port_status;
> +       u32 ret_event;
> +       u8 hdcp_cfg;
> +       int ret;
> +
> +       hdcp_cfg = hdcp_config | (enable ? 0x04 : 0) |
> +                  (HDCP_CONTENT_TYPE_0 << 3);
> +       cdns_mhdp_hdcp_tx_config(mhdp, hdcp_cfg);
> +       ret_event = cdns_mhdp_wait_for_sw_event(mhdp, CDNS_HDCP_TX_STATUS);
> +       if (!ret_event)
> +               return -1;
> +
> +       ret = cdns_mhdp_hdcp_get_status(mhdp, &hdcp_port_status);
> +       if (ret || cdns_mhdp_hdcp_handle_status(mhdp, hdcp_port_status))
> +               return -1;
> +
> +       return 0;
> +}
> +
> +static int cdns_mhdp_hdcp_auth_check(struct cdns_mhdp_device *mhdp)
> +{
> +       u16 hdcp_port_status;
> +       u32 ret_event;
> +       int ret;
> +
> +       ret_event = cdns_mhdp_wait_for_sw_event(mhdp, CDNS_HDCP_TX_STATUS);
> +       if (!ret_event)
> +               return -1;
> +
> +       ret = cdns_mhdp_hdcp_get_status(mhdp, &hdcp_port_status);
> +       if (ret || cdns_mhdp_hdcp_handle_status(mhdp, hdcp_port_status))
> +               return -1;
> +
> +       if (hdcp_port_status & 1) {
> +               dev_dbg(mhdp->dev, "Authentication completed successfully!\n");
> +               return 0;
> +       }
> +
> +       dev_dbg(mhdp->dev, "Authentication failed\n");
> +
> +       return -1;
> +}
> +
> +static int cdns_mhdp_hdcp_check_receviers(struct cdns_mhdp_device *mhdp)
> +{
> +       u8 hdcp_rec_id[HDCP_MAX_RECEIVERS][HDCP_RECEIVER_ID_SIZE_BYTES];
> +       u8 hdcp_num_rec;
> +       u32 ret_event;
> +
> +       ret_event = cdns_mhdp_wait_for_sw_event(mhdp,
> +                                               CDNS_HDCP_TX_IS_RCVR_ID_VALID);
> +       if (!ret_event)
> +               return -1;
> +
> +       hdcp_num_rec = 0;
> +       memset(&hdcp_rec_id, 0, sizeof(hdcp_rec_id));
> +       cdns_mhdp_hdcp_rx_id_valid(mhdp, &hdcp_num_rec, (u8 *)hdcp_rec_id);
> +       cdns_mhdp_hdcp_rx_id_valid_response(mhdp, 1);
> +
> +       return 0;
> +}
> +
> +static int cdns_mhdp_hdcp_auth_22(struct cdns_mhdp_device *mhdp)
> +{
> +       u8 resp[HDCP_STATUS_SIZE];
> +       u16 hdcp_port_status;
> +       u32 ret_event;
> +       int ret;
> +
> +       dev_dbg(mhdp->dev, "HDCP: Start 2.2 Authentication\n");
> +       ret_event = cdns_mhdp_wait_for_sw_event(mhdp,
> +                                               CDNS_HDCP2_TX_IS_KM_STORED);
> +       if (!ret_event)
> +               return -1;
> +
> +       if (ret_event & CDNS_HDCP_TX_STATUS) {
> +               mhdp->sw_events &= ~CDNS_HDCP_TX_STATUS;
> +               ret = cdns_mhdp_hdcp_get_status(mhdp, &hdcp_port_status);
> +               if (ret || cdns_mhdp_hdcp_handle_status(mhdp, hdcp_port_status))
> +                       return -1;
> +       }
> +
> +       cdns_mhdp_hdcp_tx_is_km_stored(mhdp, resp, sizeof(resp));
> +       cdns_mhdp_hdcp_km_stored_resp(mhdp, 0, NULL);
> +
> +       if (cdns_mhdp_hdcp_check_receviers(mhdp))
> +               return -1;
> +
> +       return 0;
> +}
> +
> +static inline int cdns_mhdp_hdcp_auth_14(struct cdns_mhdp_device *mhdp)
> +{
> +       dev_dbg(mhdp->dev, "HDCP: Starting 1.4 Authentication\n");
> +       return cdns_mhdp_hdcp_check_receviers(mhdp);
> +}
> +
> +static int cdns_mhdp_hdcp_auth(struct cdns_mhdp_device *mhdp,
> +                              u8 hdcp_config)
> +{
> +       int ret;
> +
> +       ret = cdns_mhdp_hdcp_set_config(mhdp, hdcp_config, true);
> +       if (ret)
> +               goto auth_failed;
> +
> +       if (hdcp_config == HDCP_TX_1)
> +               ret = cdns_mhdp_hdcp_auth_14(mhdp);
> +       else
> +               ret = cdns_mhdp_hdcp_auth_22(mhdp);
> +
> +       if (ret)
> +               goto auth_failed;
> +
> +       ret = cdns_mhdp_hdcp_auth_check(mhdp);
> +       if (ret)
> +               ret = cdns_mhdp_hdcp_auth_check(mhdp);
> +
> +auth_failed:
> +       return ret;
> +}
> +
> +static int _cdns_mhdp_hdcp_disable(struct cdns_mhdp_device *mhdp)
> +{
> +       int ret;
> +
> +       dev_dbg(mhdp->dev, "[%s:%d] HDCP is being disabled...\n",
> +               mhdp->connector.name, mhdp->connector.base.id);
> +
> +       ret = cdns_mhdp_hdcp_set_config(mhdp, 0, false);
> +
> +       return ret;
> +}
> +
> +static int _cdns_mhdp_hdcp_enable(struct cdns_mhdp_device *mhdp)
> +{
> +       int ret, tries = 3;
> +       u32 i;
> +
> +       for (i = 0; i < tries; i++) {
> +               if (mhdp->hdcp.config & HDCP_CONFIG_2_2) {
> +                       ret = cdns_mhdp_hdcp_auth(mhdp, HDCP_TX_2);
> +                       if (!ret)
> +                               return 0;
> +               }
> +               _cdns_mhdp_hdcp_disable(mhdp);
> +
> +               if (mhdp->hdcp.config & HDCP_CONFIG_1_4) {
> +                       ret = cdns_mhdp_hdcp_auth(mhdp, HDCP_TX_1);
> +                       if (!ret)
> +                               return 0;
> +               }
> +               _cdns_mhdp_hdcp_disable(mhdp);
> +       }
> +
> +       dev_err(mhdp->dev, "HDCP authentication failed (%d tries/%d)\n",
> +               tries, ret);
> +
> +       return ret;
> +}
> +
> +static int cdns_mhdp_hdcp_check_link(struct cdns_mhdp_device *mhdp)
> +{
> +       u16 hdcp_port_status;
> +       int ret = 0;
> +
> +       mutex_lock(&mhdp->hdcp.mutex);
> +       if (mhdp->hdcp.value == DRM_MODE_CONTENT_PROTECTION_UNDESIRED)
> +               goto out;
> +
> +       ret = cdns_mhdp_hdcp_get_status(mhdp, &hdcp_port_status);
> +       if (!ret && hdcp_port_status & HDCP_PORT_STS_AUTH)
> +               goto out;
> +
> +       dev_err(mhdp->dev,
> +               "[%s:%d] HDCP link failed, retrying authentication\n",
> +               mhdp->connector.name, mhdp->connector.base.id);
> +
> +       ret = _cdns_mhdp_hdcp_disable(mhdp);
> +       if (ret) {
> +               mhdp->hdcp.value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
> +               schedule_work(&mhdp->hdcp.prop_work);
> +               goto out;
> +       }
> +
> +       ret = _cdns_mhdp_hdcp_enable(mhdp);
> +       if (ret) {
> +               mhdp->hdcp.value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
> +               schedule_work(&mhdp->hdcp.prop_work);
> +       }
> +out:
> +       mutex_unlock(&mhdp->hdcp.mutex);
> +       return ret;
> +}
> +
> +static void cdns_mhdp_hdcp_check_work(struct work_struct *work)
> +{
> +       struct delayed_work *d_work = to_delayed_work(work);
> +       struct cdns_mhdp_hdcp *hdcp = container_of(d_work,
> +                                                  struct cdns_mhdp_hdcp,
> +                                                  check_work);
> +       struct cdns_mhdp_device *mhdp = container_of(hdcp,
> +                                                    struct cdns_mhdp_device,
> +                                                    hdcp);
> +
> +       if (!cdns_mhdp_hdcp_check_link(mhdp))
> +               schedule_delayed_work(&hdcp->check_work,
> +                                     DRM_HDCP_CHECK_PERIOD_MS);
> +}
> +
> +static void cdns_mhdp_hdcp_prop_work(struct work_struct *work)
> +{
> +       struct cdns_mhdp_hdcp *hdcp = container_of(work,
> +                                                  struct cdns_mhdp_hdcp,
> +                                                  prop_work);
> +       struct cdns_mhdp_device *mhdp = container_of(hdcp,
> +                                                    struct cdns_mhdp_device,
> +                                                    hdcp);
> +       struct drm_device *dev = mhdp->connector.dev;
> +       struct drm_connector_state *state;
> +
> +       drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> +       mutex_lock(&mhdp->hdcp.mutex);
> +       if (mhdp->hdcp.value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
> +               state = mhdp->connector.state;
> +               state->content_protection = mhdp->hdcp.value;
> +       }
> +       mutex_unlock(&mhdp->hdcp.mutex);
> +       drm_modeset_unlock(&dev->mode_config.connection_mutex);
> +}
> +
> +int cdns_mhdp_hdcp_set_lc(struct cdns_mhdp_device *mhdp, u8 *val)
> +{
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_GENERAL,
> +                                           HDCP_GENERAL_SET_LC_128,
> +                                           16, val);
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +int
> +cdns_mhdp_hdcp_set_public_key_params(struct cdns_mhdp_device *mhdp,
> +                                    struct cdns_hdcp_tx_public_key_param *val)
> +{
> +       int ret;
> +
> +       mutex_lock(&mhdp->mbox_mutex);
> +       ret = cdns_mhdp_secure_mailbox_send(mhdp, MB_MODULE_ID_HDCP_TX,
> +                                           HDCP2X_TX_SET_PUBLIC_KEY_PARAMS,
> +                                           sizeof(*val), (u8 *)val);
> +       mutex_unlock(&mhdp->mbox_mutex);
> +
> +       return ret;
> +}
> +
> +int cdns_mhdp_hdcp_enable(struct cdns_mhdp_device *mhdp)
> +{
> +       int ret;
> +
> +       mutex_lock(&mhdp->hdcp.mutex);
> +       ret = _cdns_mhdp_hdcp_enable(mhdp);
> +       if (ret)
> +               goto out;
> +
> +       mhdp->hdcp.value = DRM_MODE_CONTENT_PROTECTION_ENABLED;
> +       schedule_work(&mhdp->hdcp.prop_work);
> +       schedule_delayed_work(&mhdp->hdcp.check_work,
> +                             DRM_HDCP_CHECK_PERIOD_MS);
> +out:
> +       mutex_unlock(&mhdp->hdcp.mutex);
> +       return ret;
> +}
> +
> +int cdns_mhdp_hdcp_disable(struct cdns_mhdp_device *mhdp)
> +{
> +       int ret = 0;
> +
> +       mutex_lock(&mhdp->hdcp.mutex);
> +       if (mhdp->hdcp.value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
> +               mhdp->hdcp.value = DRM_MODE_CONTENT_PROTECTION_UNDESIRED;
> +               schedule_work(&mhdp->hdcp.prop_work);
> +               ret = _cdns_mhdp_hdcp_disable(mhdp);
> +       }
> +       mutex_unlock(&mhdp->hdcp.mutex);
> +       cancel_delayed_work_sync(&mhdp->hdcp.check_work);
> +
> +       return ret;
> +}
> +
> +int cdns_mhdp_hdcp_init(struct cdns_mhdp_device *mhdp,
> +                       struct device_node *of_node)
> +{
> +       u32 config;
> +       int ret;
> +
> +       ret = of_property_read_u32(of_node, "hdcp-config", &config);
> +       if (ret)
> +               mhdp->hdcp.config = HDCP_CONFIG_ALL;
> +       else
> +               mhdp->hdcp.config = config;
> +
> +       INIT_DELAYED_WORK(&mhdp->hdcp.check_work, cdns_mhdp_hdcp_check_work);
> +       INIT_WORK(&mhdp->hdcp.prop_work, cdns_mhdp_hdcp_prop_work);
> +       mutex_init(&mhdp->hdcp.mutex);
> +
> +       return 0;
> +}
> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.h b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.h
> new file mode 100644
> index 000000000000..fc694a9e4c04
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.h
> @@ -0,0 +1,89 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Cadence MHDP8546 DP bridge driver.
> + *
> + * Copyright (C) 2020 Cadence Design Systems, Inc.
> + *
> + */
> +
> +#ifndef CDNS_MHDP8546_HDCP_H
> +#define CDNS_MHDP8546_HDCP_H
> +
> +#include "cdns-mhdp8546-core.h"
> +
> +#define HDCP_MAX_RECEIVERS 32
> +#define HDCP_RECEIVER_ID_SIZE_BYTES 5
> +#define HDCP_STATUS_SIZE         0x5
> +#define HDCP_PORT_STS_AUTH       0x1
> +#define HDCP_PORT_STS_LAST_ERR_SHIFT 0x5
> +#define HDCP_PORT_STS_LAST_ERR_MASK  (0x0F << 5)
> +#define GET_HDCP_PORT_STS_LAST_ERR(__sts__) \
> +       (((__sts__) & HDCP_PORT_STS_LAST_ERR_MASK) >> \
> +       HDCP_PORT_STS_LAST_ERR_SHIFT)
> +
> +#define HDCP_CONFIG_1_4     BIT(0) /* use HDCP 1.4 only */
> +#define HDCP_CONFIG_2_2     BIT(1) /* use HDCP 2.2 only */
> +/* use All HDCP versions */
> +#define HDCP_CONFIG_ALL     (BIT(0) | BIT(1))
> +#define HDCP_CONFIG_NONE    0
> +
> +enum {
> +       HDCP_GENERAL_SET_LC_128,
> +       HDCP_SET_SEED,
> +};
> +
> +enum {
> +       HDCP_TRAN_CONFIGURATION,
> +       HDCP2X_TX_SET_PUBLIC_KEY_PARAMS,
> +       HDCP2X_TX_SET_DEBUG_RANDOM_NUMBERS,
> +       HDCP2X_TX_RESPOND_KM,
> +       HDCP1_TX_SEND_KEYS,
> +       HDCP1_TX_SEND_RANDOM_AN,
> +       HDCP_TRAN_STATUS_CHANGE,
> +       HDCP2X_TX_IS_KM_STORED,
> +       HDCP2X_TX_STORE_KM,
> +       HDCP_TRAN_IS_REC_ID_VALID,
> +       HDCP_TRAN_RESPOND_RECEIVER_ID_VALID,
> +       HDCP_TRAN_TEST_KEYS,
> +       HDCP2X_TX_SET_KM_KEY_PARAMS,
> +       HDCP_NUM_OF_SUPPORTED_MESSAGES
> +};
> +
> +enum {
> +       HDCP_CONTENT_TYPE_0,
> +       HDCP_CONTENT_TYPE_1,
> +};
> +
> +#define DRM_HDCP_CHECK_PERIOD_MS (128 * 16)
> +
> +#define HDCP_PAIRING_R_ID 5
> +#define HDCP_PAIRING_M_LEN 16
> +#define HDCP_KM_LEN 16
> +#define HDCP_PAIRING_M_EKH 16
> +
> +struct cdns_hdcp_pairing_data {
> +       u8 receiver_id[HDCP_PAIRING_R_ID];
> +       u8 m[HDCP_PAIRING_M_LEN];
> +       u8 km[HDCP_KM_LEN];
> +       u8 ekh[HDCP_PAIRING_M_EKH];
> +};
> +
> +enum {
> +       HDCP_TX_2,
> +       HDCP_TX_1,
> +       HDCP_TX_BOTH,
> +};
> +
> +#define DLP_MODULUS_N 384
> +#define DLP_E 3
> +
> +struct cdns_hdcp_tx_public_key_param {
> +       u8 N[DLP_MODULUS_N];
> +       u8 E[DLP_E];
> +};
> +
> +int cdns_mhdp_hdcp_enable(struct cdns_mhdp_device *mhdp);
> +int cdns_mhdp_hdcp_disable(struct cdns_mhdp_device *mhdp);
> +int cdns_mhdp_hdcp_init(struct cdns_mhdp_device *mhdp, struct device_node *of_node);
> +
> +#endif
> --
> 2.25.1
>