diff mbox series

[4/5] drm/xe/hdcp: Enable HDCP for XE

Message ID 20240209101412.1326176-5-suraj.kandpal@intel.com (mailing list archive)
State New, archived
Headers show
Series XE HDCP Enablement | expand

Commit Message

Kandpal, Suraj Feb. 9, 2024, 10:14 a.m. UTC
Enable HDCP for Xe by defining functions which take care of
interaction of HDCP as a client with the GSC CS interface.

--v2
-add kfree at appropriate place [Daniele]
-remove useless define [Daniele]
-move host session logic to xe_gsc_submit.c [Daniele]
-call xe_gsc_check_and_update_pending directly in an if condition
[Daniele]
-use xe_device instead of drm_i915_private [Daniele]

--v3
-use xe prefix for newly exposed function [Daniele]
-remove client specific defines from intel_gsc_mtl_header [Daniele]
-add missing kfree() [Daniele]
-have NULL check for hdcp_message in finish function [Daniele]
-dont have too many variable declarations in the same line [Daniele]

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
---
 drivers/gpu/drm/xe/display/xe_hdcp_gsc.c | 180 ++++++++++++++++++++++-
 drivers/gpu/drm/xe/xe_gsc_submit.c       |  15 ++
 drivers/gpu/drm/xe/xe_gsc_submit.h       |   1 +
 3 files changed, 193 insertions(+), 3 deletions(-)

Comments

kernel test robot Feb. 9, 2024, 5:50 p.m. UTC | #1
Hi Suraj,

kernel test robot noticed the following build warnings:

[auto build test WARNING on drm-xe/drm-xe-next]
[also build test WARNING on drm-tip/drm-tip]
[cannot apply to drm-intel/for-linux-next drm-intel/for-linux-next-fixes linus/master v6.8-rc3 next-20240209]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Suraj-Kandpal/drm-i915-hdcp-Move-intel_hdcp_gsc_message-def-away-from-header-file/20240209-181915
base:   https://gitlab.freedesktop.org/drm/xe/kernel.git drm-xe-next
patch link:    https://lore.kernel.org/r/20240209101412.1326176-5-suraj.kandpal%40intel.com
patch subject: [PATCH 4/5] drm/xe/hdcp: Enable HDCP for XE
config: loongarch-allmodconfig (https://download.01.org/0day-ci/archive/20240210/202402100132.XIP3zz5i-lkp@intel.com/config)
compiler: loongarch64-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240210/202402100132.XIP3zz5i-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202402100132.XIP3zz5i-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/xe/xe_gsc_submit.c:50: warning: expecting prototype for xe_gsc_get_host_session_id(). Prototype was for xe_gsc_create_host_session_id() instead


vim +50 drivers/gpu/drm/xe/xe_gsc_submit.c

    42	
    43	/**
    44	 * xe_gsc_get_host_session_id - Creates a random 64 bit host_session id with
    45	 * bits 56-63 masked.
    46	 *
    47	 * Returns: random host_session_id which can be used to send messages to gsc cs
    48	 */
    49	u64 xe_gsc_create_host_session_id(void)
  > 50	{
    51		u64 host_session_id;
    52	
    53		get_random_bytes(&host_session_id, sizeof(u64));
    54		host_session_id &= ~HOST_SESSION_CLIENT_MASK;
    55		return host_session_id;
    56	}
    57
Daniele Ceraolo Spurio Feb. 13, 2024, 11:30 p.m. UTC | #2
On 2/9/2024 2:14 AM, Suraj Kandpal wrote:
> Enable HDCP for Xe by defining functions which take care of
> interaction of HDCP as a client with the GSC CS interface.
>
> --v2
> -add kfree at appropriate place [Daniele]
> -remove useless define [Daniele]
> -move host session logic to xe_gsc_submit.c [Daniele]
> -call xe_gsc_check_and_update_pending directly in an if condition
> [Daniele]
> -use xe_device instead of drm_i915_private [Daniele]
>
> --v3
> -use xe prefix for newly exposed function [Daniele]
> -remove client specific defines from intel_gsc_mtl_header [Daniele]
> -add missing kfree() [Daniele]
> -have NULL check for hdcp_message in finish function [Daniele]
> -dont have too many variable declarations in the same line [Daniele]
>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>   drivers/gpu/drm/xe/display/xe_hdcp_gsc.c | 180 ++++++++++++++++++++++-
>   drivers/gpu/drm/xe/xe_gsc_submit.c       |  15 ++
>   drivers/gpu/drm/xe/xe_gsc_submit.h       |   1 +
>   3 files changed, 193 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> index 425db3532ce5..aa8c13916bb6 100644
> --- a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> +++ b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> @@ -4,12 +4,27 @@
>    */
>   
>   #include <drm/drm_print.h>
> +#include <linux/delay.h>
>   
> +#include "abi/gsc_command_header_abi.h"
>   #include "intel_hdcp_gsc.h"
>   #include "xe_device_types.h"
>   #include "xe_gt.h"
>   #include "xe_gsc_proxy.h"
>   #include "xe_pm.h"
> +#include "xe_bo.h"
> +#include "xe_map.h"
> +#include "xe_gsc_submit.h"
> +
> +#define HECI_MEADDRESS_HDCP 18
> +
> +struct intel_hdcp_gsc_message {
> +	struct xe_bo *hdcp_bo;
> +	u64 hdcp_cmd_in;
> +	u64 hdcp_cmd_out;
> +};
> +
> +#define HDCP_GSC_HEADER_SIZE sizeof(struct intel_gsc_mtl_header)
>   
>   bool intel_hdcp_gsc_cs_required(struct xe_device *xe)
>   {
> @@ -40,19 +55,178 @@ bool intel_hdcp_gsc_check_status(struct xe_device *xe)
>   	return ret;
>   }
>   
> +/*This function helps allocate memory for the command that we will send to gsc cs */
> +static int intel_hdcp_gsc_initialize_message(struct xe_device *xe,
> +					     struct intel_hdcp_gsc_message *hdcp_message)
> +{
> +	struct xe_bo *bo = NULL;
> +	u64 cmd_in, cmd_out;
> +	int ret = 0;
> +
> +	/* allocate object of two page for HDCP command memory and store it */
> +	xe_device_mem_access_get(xe);
> +	bo = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe), NULL, PAGE_SIZE * 2,
> +				  ttm_bo_type_kernel,
> +				  XE_BO_CREATE_SYSTEM_BIT |
> +				  XE_BO_CREATE_GGTT_BIT);
> +
> +	if (IS_ERR(bo)) {
> +		drm_err(&xe->drm, "Failed to allocate bo for HDCP streaming command!\n");
> +		ret = PTR_ERR(bo);
> +		goto out;
> +	}
> +
> +	cmd_in = xe_bo_ggtt_addr(bo);
> +	cmd_out = cmd_in + PAGE_SIZE;
> +	xe_map_memset(xe, &bo->vmap, 0, 0, bo->size);
> +
> +	hdcp_message->hdcp_bo = bo;
> +	hdcp_message->hdcp_cmd_in = cmd_in;
> +	hdcp_message->hdcp_cmd_out = cmd_out;
> +out:
> +	xe_device_mem_access_put(xe);
> +	return ret;
> +}
> +
> +static int intel_hdcp_gsc_hdcp2_init(struct xe_device *xe)
> +{
> +	struct intel_hdcp_gsc_message *hdcp_message;
> +	int ret;
> +
> +	hdcp_message = kzalloc(sizeof(*hdcp_message), GFP_KERNEL);
> +
> +	if (!hdcp_message)
> +		return -ENOMEM;
> +
> +	/*
> +	 * NOTE: No need to lock the comp mutex here as it is already
> +	 * going to be taken before this function called
> +	 */
> +	ret = intel_hdcp_gsc_initialize_message(xe, hdcp_message);
> +	xe->display.hdcp.hdcp_message = hdcp_message;
> +
> +	if (ret) {
> +		drm_err(&xe->drm, "Could not initialize hdcp_message\n");
> +		kfree(hdcp_message);

Here you're leaving xe->display.hdcp.hdcp_message pointing to a memory 
location that we no longer own. is that safe for the _fini function?

LGTM apart from this (assuming it is going to be squashed with the next 
patch for merge).

Daniele

> +	}
> +
> +	return ret;
> +}
> +
>   int intel_hdcp_gsc_init(struct xe_device *xe)
>   {
> -	drm_dbg_kms(&xe->drm, "HDCP support not yet implemented\n");
> -	return -ENODEV;
> +	struct i915_hdcp_arbiter *data;
> +	int ret;
> +
> +	data = kzalloc(sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	mutex_lock(&xe->display.hdcp.hdcp_mutex);
> +	xe->display.hdcp.arbiter = data;
> +	xe->display.hdcp.arbiter->hdcp_dev = xe->drm.dev;
> +	xe->display.hdcp.arbiter->ops = &gsc_hdcp_ops;
> +	ret = intel_hdcp_gsc_hdcp2_init(xe);
> +	if (ret)
> +		kfree(data);
> +
> +	mutex_unlock(&xe->display.hdcp.hdcp_mutex);
> +
> +	return ret;
>   }
>   
>   void intel_hdcp_gsc_fini(struct xe_device *xe)
>   {
> +	struct intel_hdcp_gsc_message *hdcp_message =
> +					xe->display.hdcp.hdcp_message;
> +
> +	if (!hdcp_message)
> +		return;
> +
> +	xe_bo_unpin_map_no_vm(hdcp_message->hdcp_bo);
> +	kfree(hdcp_message);
> +}
> +
> +static int xe_gsc_send_sync(struct xe_device *xe,
> +			    struct intel_hdcp_gsc_message *hdcp_message,
> +			    u32 msg_size_in, u32 msg_size_out,
> +			    u32 addr_out_off)
> +{
> +	struct xe_gt *gt = hdcp_message->hdcp_bo->tile->media_gt;
> +	struct iosys_map *map = &hdcp_message->hdcp_bo->vmap;
> +	struct xe_gsc *gsc = &gt->uc.gsc;
> +	int ret;
> +
> +	ret = xe_gsc_pkt_submit_kernel(gsc, hdcp_message->hdcp_cmd_in, msg_size_in,
> +				       hdcp_message->hdcp_cmd_out, msg_size_out);
> +	if (ret) {
> +		drm_err(&xe->drm, "failed to send gsc HDCP msg (%d)\n", ret);
> +		return ret;
> +	}
> +
> +	if (xe_gsc_check_and_update_pending(xe, map, 0, map, addr_out_off))
> +		return -EAGAIN;
> +
> +	ret = xe_gsc_read_out_header(xe, map, addr_out_off,
> +				     sizeof(struct hdcp_cmd_header), NULL);
> +
> +	return ret;
>   }
>   
>   ssize_t intel_hdcp_gsc_msg_send(struct xe_device *xe, u8 *msg_in,
>   				size_t msg_in_len, u8 *msg_out,
>   				size_t msg_out_len)
>   {
> -	return -ENODEV;
> +	const size_t max_msg_size = PAGE_SIZE - HDCP_GSC_HEADER_SIZE;
> +	struct intel_hdcp_gsc_message *hdcp_message;
> +	u64 host_session_id;
> +	u32 msg_size_in, msg_size_out;
> +	u32 addr_out_off, addr_in_wr_off = 0;
> +	int ret, tries = 0;
> +
> +	if (msg_in_len > max_msg_size || msg_out_len > max_msg_size) {
> +		ret = -ENOSPC;
> +		goto out;
> +	}
> +
> +	msg_size_in = msg_in_len + HDCP_GSC_HEADER_SIZE;
> +	msg_size_out = msg_out_len + HDCP_GSC_HEADER_SIZE;
> +	hdcp_message = xe->display.hdcp.hdcp_message;
> +	addr_out_off = PAGE_SIZE;
> +
> +	host_session_id = xe_gsc_create_host_session_id();
> +	xe_device_mem_access_get(xe);
> +	addr_in_wr_off = xe_gsc_emit_header(xe, &hdcp_message->hdcp_bo->vmap,
> +					    addr_in_wr_off, HECI_MEADDRESS_HDCP,
> +					    host_session_id, msg_in_len);
> +	xe_map_memcpy_to(xe, &hdcp_message->hdcp_bo->vmap, addr_in_wr_off,
> +			 msg_in, msg_in_len);
> +	/*
> +	 * Keep sending request in case the pending bit is set no need to add
> +	 * message handle as we are using same address hence loc. of header is
> +	 * same and it will contain the message handle. we will send the message
> +	 * 20 times each message 50 ms apart
> +	 */
> +	do {
> +		ret = xe_gsc_send_sync(xe, hdcp_message, msg_size_in, msg_size_out,
> +				       addr_out_off);
> +
> +		/* Only try again if gsc says so */
> +		if (ret != -EAGAIN)
> +			break;
> +
> +		msleep(50);
> +
> +	} while (++tries < 20);
> +
> +	if (ret)
> +		goto out;
> +
> +	xe_map_memcpy_from(xe, msg_out, &hdcp_message->hdcp_bo->vmap,
> +			   addr_out_off + HDCP_GSC_HEADER_SIZE,
> +			   msg_out_len);
> +
> +out:
> +	xe_device_mem_access_put(xe);
> +	return ret;
>   }
> diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.c b/drivers/gpu/drm/xe/xe_gsc_submit.c
> index 348994b271be..9a18f5667db3 100644
> --- a/drivers/gpu/drm/xe/xe_gsc_submit.c
> +++ b/drivers/gpu/drm/xe/xe_gsc_submit.c
> @@ -40,6 +40,21 @@ gsc_to_gt(struct xe_gsc *gsc)
>   	return container_of(gsc, struct xe_gt, uc.gsc);
>   }
>   
> +/**
> + * xe_gsc_get_host_session_id - Creates a random 64 bit host_session id with
> + * bits 56-63 masked.
> + *
> + * Returns: random host_session_id which can be used to send messages to gsc cs
> + */
> +u64 xe_gsc_create_host_session_id(void)
> +{
> +	u64 host_session_id;
> +
> +	get_random_bytes(&host_session_id, sizeof(u64));
> +	host_session_id &= ~HOST_SESSION_CLIENT_MASK;
> +	return host_session_id;
> +}
> +
>   /**
>    * xe_gsc_emit_header - write the MTL GSC header in memory
>    * @xe: the Xe device
> diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.h b/drivers/gpu/drm/xe/xe_gsc_submit.h
> index 1939855031a6..1416b5745a4c 100644
> --- a/drivers/gpu/drm/xe/xe_gsc_submit.h
> +++ b/drivers/gpu/drm/xe/xe_gsc_submit.h
> @@ -28,4 +28,5 @@ int xe_gsc_read_out_header(struct xe_device *xe,
>   int xe_gsc_pkt_submit_kernel(struct xe_gsc *gsc, u64 addr_in, u32 size_in,
>   			     u64 addr_out, u32 size_out);
>   
> +u64 xe_gsc_create_host_session_id(void);
>   #endif
Kandpal, Suraj Feb. 14, 2024, 5:33 a.m. UTC | #3
> > interaction of HDCP as a client with the GSC CS interface.
> >
> > --v2
> > -add kfree at appropriate place [Daniele] -remove useless define
> > [Daniele] -move host session logic to xe_gsc_submit.c [Daniele] -call
> > xe_gsc_check_and_update_pending directly in an if condition [Daniele]
> > -use xe_device instead of drm_i915_private [Daniele]
> >
> > --v3
> > -use xe prefix for newly exposed function [Daniele] -remove client
> > specific defines from intel_gsc_mtl_header [Daniele] -add missing
> > kfree() [Daniele] -have NULL check for hdcp_message in finish function
> > [Daniele] -dont have too many variable declarations in the same line
> > [Daniele]
> >
> > Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> > ---
> >   drivers/gpu/drm/xe/display/xe_hdcp_gsc.c | 180
> ++++++++++++++++++++++-
> >   drivers/gpu/drm/xe/xe_gsc_submit.c       |  15 ++
> >   drivers/gpu/drm/xe/xe_gsc_submit.h       |   1 +
> >   3 files changed, 193 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > index 425db3532ce5..aa8c13916bb6 100644
> > --- a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > +++ b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
> > @@ -4,12 +4,27 @@
> >    */
> >
> >   #include <drm/drm_print.h>
> > +#include <linux/delay.h>
> >
> > +#include "abi/gsc_command_header_abi.h"
> >   #include "intel_hdcp_gsc.h"
> >   #include "xe_device_types.h"
> >   #include "xe_gt.h"
> >   #include "xe_gsc_proxy.h"
> >   #include "xe_pm.h"
> > +#include "xe_bo.h"
> > +#include "xe_map.h"
> > +#include "xe_gsc_submit.h"
> > +
> > +#define HECI_MEADDRESS_HDCP 18
> > +
> > +struct intel_hdcp_gsc_message {
> > +	struct xe_bo *hdcp_bo;
> > +	u64 hdcp_cmd_in;
> > +	u64 hdcp_cmd_out;
> > +};
> > +
> > +#define HDCP_GSC_HEADER_SIZE sizeof(struct intel_gsc_mtl_header)
> >
> >   bool intel_hdcp_gsc_cs_required(struct xe_device *xe)
> >   {
> > @@ -40,19 +55,178 @@ bool intel_hdcp_gsc_check_status(struct xe_device
> *xe)
> >   	return ret;
> >   }
> >
> > +/*This function helps allocate memory for the command that we will
> > +send to gsc cs */ static int intel_hdcp_gsc_initialize_message(struct
> xe_device *xe,
> > +					     struct intel_hdcp_gsc_message
> *hdcp_message) {
> > +	struct xe_bo *bo = NULL;
> > +	u64 cmd_in, cmd_out;
> > +	int ret = 0;
> > +
> > +	/* allocate object of two page for HDCP command memory and store
> it */
> > +	xe_device_mem_access_get(xe);
> > +	bo = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe), NULL,
> PAGE_SIZE * 2,
> > +				  ttm_bo_type_kernel,
> > +				  XE_BO_CREATE_SYSTEM_BIT |
> > +				  XE_BO_CREATE_GGTT_BIT);
> > +
> > +	if (IS_ERR(bo)) {
> > +		drm_err(&xe->drm, "Failed to allocate bo for HDCP streaming
> command!\n");
> > +		ret = PTR_ERR(bo);
> > +		goto out;
> > +	}
> > +
> > +	cmd_in = xe_bo_ggtt_addr(bo);
> > +	cmd_out = cmd_in + PAGE_SIZE;
> > +	xe_map_memset(xe, &bo->vmap, 0, 0, bo->size);
> > +
> > +	hdcp_message->hdcp_bo = bo;
> > +	hdcp_message->hdcp_cmd_in = cmd_in;
> > +	hdcp_message->hdcp_cmd_out = cmd_out;
> > +out:
> > +	xe_device_mem_access_put(xe);
> > +	return ret;
> > +}
> > +
> > +static int intel_hdcp_gsc_hdcp2_init(struct xe_device *xe) {
> > +	struct intel_hdcp_gsc_message *hdcp_message;
> > +	int ret;
> > +
> > +	hdcp_message = kzalloc(sizeof(*hdcp_message), GFP_KERNEL);
> > +
> > +	if (!hdcp_message)
> > +		return -ENOMEM;
> > +
> > +	/*
> > +	 * NOTE: No need to lock the comp mutex here as it is already
> > +	 * going to be taken before this function called
> > +	 */
> > +	ret = intel_hdcp_gsc_initialize_message(xe, hdcp_message);
> > +	xe->display.hdcp.hdcp_message = hdcp_message;
> > +
> > +	if (ret) {
> > +		drm_err(&xe->drm, "Could not initialize hdcp_message\n");
> > +		kfree(hdcp_message);
> 
> Here you're leaving xe->display.hdcp.hdcp_message pointing to a memory
> location that we no longer own. is that safe for the _fini function?
> 

Would it be better to not have a kfree here if initialization fails it gets taken care of
In finish function anyways that would be safer I presume.

> LGTM apart from this (assuming it is going to be squashed with the next
> patch for merge).

Yes this will be squashed with the next patch when I send the new revision

Regards,
Suraj Kandpal
> 
> Daniele
> 
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> >   int intel_hdcp_gsc_init(struct xe_device *xe)
> >   {
> > -	drm_dbg_kms(&xe->drm, "HDCP support not yet implemented\n");
> > -	return -ENODEV;
> > +	struct i915_hdcp_arbiter *data;
> > +	int ret;
> > +
> > +	data = kzalloc(sizeof(*data), GFP_KERNEL);
> > +	if (!data)
> > +		return -ENOMEM;
> > +
> > +	mutex_lock(&xe->display.hdcp.hdcp_mutex);
> > +	xe->display.hdcp.arbiter = data;
> > +	xe->display.hdcp.arbiter->hdcp_dev = xe->drm.dev;
> > +	xe->display.hdcp.arbiter->ops = &gsc_hdcp_ops;
> > +	ret = intel_hdcp_gsc_hdcp2_init(xe);
> > +	if (ret)
> > +		kfree(data);
> > +
> > +	mutex_unlock(&xe->display.hdcp.hdcp_mutex);
> > +
> > +	return ret;
> >   }
> >
> >   void intel_hdcp_gsc_fini(struct xe_device *xe)
> >   {
> > +	struct intel_hdcp_gsc_message *hdcp_message =
> > +					xe->display.hdcp.hdcp_message;
> > +
> > +	if (!hdcp_message)
> > +		return;
> > +
> > +	xe_bo_unpin_map_no_vm(hdcp_message->hdcp_bo);
> > +	kfree(hdcp_message);
> > +}
> > +
> > +static int xe_gsc_send_sync(struct xe_device *xe,
> > +			    struct intel_hdcp_gsc_message *hdcp_message,
> > +			    u32 msg_size_in, u32 msg_size_out,
> > +			    u32 addr_out_off)
> > +{
> > +	struct xe_gt *gt = hdcp_message->hdcp_bo->tile->media_gt;
> > +	struct iosys_map *map = &hdcp_message->hdcp_bo->vmap;
> > +	struct xe_gsc *gsc = &gt->uc.gsc;
> > +	int ret;
> > +
> > +	ret = xe_gsc_pkt_submit_kernel(gsc, hdcp_message->hdcp_cmd_in,
> msg_size_in,
> > +				       hdcp_message->hdcp_cmd_out,
> msg_size_out);
> > +	if (ret) {
> > +		drm_err(&xe->drm, "failed to send gsc HDCP msg (%d)\n",
> ret);
> > +		return ret;
> > +	}
> > +
> > +	if (xe_gsc_check_and_update_pending(xe, map, 0, map,
> addr_out_off))
> > +		return -EAGAIN;
> > +
> > +	ret = xe_gsc_read_out_header(xe, map, addr_out_off,
> > +				     sizeof(struct hdcp_cmd_header), NULL);
> > +
> > +	return ret;
> >   }
> >
> >   ssize_t intel_hdcp_gsc_msg_send(struct xe_device *xe, u8 *msg_in,
> >   				size_t msg_in_len, u8 *msg_out,
> >   				size_t msg_out_len)
> >   {
> > -	return -ENODEV;
> > +	const size_t max_msg_size = PAGE_SIZE - HDCP_GSC_HEADER_SIZE;
> > +	struct intel_hdcp_gsc_message *hdcp_message;
> > +	u64 host_session_id;
> > +	u32 msg_size_in, msg_size_out;
> > +	u32 addr_out_off, addr_in_wr_off = 0;
> > +	int ret, tries = 0;
> > +
> > +	if (msg_in_len > max_msg_size || msg_out_len > max_msg_size) {
> > +		ret = -ENOSPC;
> > +		goto out;
> > +	}
> > +
> > +	msg_size_in = msg_in_len + HDCP_GSC_HEADER_SIZE;
> > +	msg_size_out = msg_out_len + HDCP_GSC_HEADER_SIZE;
> > +	hdcp_message = xe->display.hdcp.hdcp_message;
> > +	addr_out_off = PAGE_SIZE;
> > +
> > +	host_session_id = xe_gsc_create_host_session_id();
> > +	xe_device_mem_access_get(xe);
> > +	addr_in_wr_off = xe_gsc_emit_header(xe, &hdcp_message-
> >hdcp_bo->vmap,
> > +					    addr_in_wr_off,
> HECI_MEADDRESS_HDCP,
> > +					    host_session_id, msg_in_len);
> > +	xe_map_memcpy_to(xe, &hdcp_message->hdcp_bo->vmap,
> addr_in_wr_off,
> > +			 msg_in, msg_in_len);
> > +	/*
> > +	 * Keep sending request in case the pending bit is set no need to add
> > +	 * message handle as we are using same address hence loc. of header
> is
> > +	 * same and it will contain the message handle. we will send the
> message
> > +	 * 20 times each message 50 ms apart
> > +	 */
> > +	do {
> > +		ret = xe_gsc_send_sync(xe, hdcp_message, msg_size_in,
> msg_size_out,
> > +				       addr_out_off);
> > +
> > +		/* Only try again if gsc says so */
> > +		if (ret != -EAGAIN)
> > +			break;
> > +
> > +		msleep(50);
> > +
> > +	} while (++tries < 20);
> > +
> > +	if (ret)
> > +		goto out;
> > +
> > +	xe_map_memcpy_from(xe, msg_out, &hdcp_message->hdcp_bo-
> >vmap,
> > +			   addr_out_off + HDCP_GSC_HEADER_SIZE,
> > +			   msg_out_len);
> > +
> > +out:
> > +	xe_device_mem_access_put(xe);
> > +	return ret;
> >   }
> > diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.c
> > b/drivers/gpu/drm/xe/xe_gsc_submit.c
> > index 348994b271be..9a18f5667db3 100644
> > --- a/drivers/gpu/drm/xe/xe_gsc_submit.c
> > +++ b/drivers/gpu/drm/xe/xe_gsc_submit.c
> > @@ -40,6 +40,21 @@ gsc_to_gt(struct xe_gsc *gsc)
> >   	return container_of(gsc, struct xe_gt, uc.gsc);
> >   }
> >
> > +/**
> > + * xe_gsc_get_host_session_id - Creates a random 64 bit host_session
> > +id with
> > + * bits 56-63 masked.
> > + *
> > + * Returns: random host_session_id which can be used to send messages
> > +to gsc cs  */
> > +u64 xe_gsc_create_host_session_id(void)
> > +{
> > +	u64 host_session_id;
> > +
> > +	get_random_bytes(&host_session_id, sizeof(u64));
> > +	host_session_id &= ~HOST_SESSION_CLIENT_MASK;
> > +	return host_session_id;
> > +}
> > +
> >   /**
> >    * xe_gsc_emit_header - write the MTL GSC header in memory
> >    * @xe: the Xe device
> > diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.h
> > b/drivers/gpu/drm/xe/xe_gsc_submit.h
> > index 1939855031a6..1416b5745a4c 100644
> > --- a/drivers/gpu/drm/xe/xe_gsc_submit.h
> > +++ b/drivers/gpu/drm/xe/xe_gsc_submit.h
> > @@ -28,4 +28,5 @@ int xe_gsc_read_out_header(struct xe_device *xe,
> >   int xe_gsc_pkt_submit_kernel(struct xe_gsc *gsc, u64 addr_in, u32 size_in,
> >   			     u64 addr_out, u32 size_out);
> >
> > +u64 xe_gsc_create_host_session_id(void);
> >   #endif
Daniele Ceraolo Spurio Feb. 14, 2024, 5:05 p.m. UTC | #4
On 2/13/2024 9:33 PM, Kandpal, Suraj wrote:
>>> interaction of HDCP as a client with the GSC CS interface.
>>>
>>> --v2
>>> -add kfree at appropriate place [Daniele] -remove useless define
>>> [Daniele] -move host session logic to xe_gsc_submit.c [Daniele] -call
>>> xe_gsc_check_and_update_pending directly in an if condition [Daniele]
>>> -use xe_device instead of drm_i915_private [Daniele]
>>>
>>> --v3
>>> -use xe prefix for newly exposed function [Daniele] -remove client
>>> specific defines from intel_gsc_mtl_header [Daniele] -add missing
>>> kfree() [Daniele] -have NULL check for hdcp_message in finish function
>>> [Daniele] -dont have too many variable declarations in the same line
>>> [Daniele]
>>>
>>> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
>>> ---
>>>    drivers/gpu/drm/xe/display/xe_hdcp_gsc.c | 180
>> ++++++++++++++++++++++-
>>>    drivers/gpu/drm/xe/xe_gsc_submit.c       |  15 ++
>>>    drivers/gpu/drm/xe/xe_gsc_submit.h       |   1 +
>>>    3 files changed, 193 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
>>> b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
>>> index 425db3532ce5..aa8c13916bb6 100644
>>> --- a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
>>> +++ b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
>>> @@ -4,12 +4,27 @@
>>>     */
>>>
>>>    #include <drm/drm_print.h>
>>> +#include <linux/delay.h>
>>>
>>> +#include "abi/gsc_command_header_abi.h"
>>>    #include "intel_hdcp_gsc.h"
>>>    #include "xe_device_types.h"
>>>    #include "xe_gt.h"
>>>    #include "xe_gsc_proxy.h"
>>>    #include "xe_pm.h"
>>> +#include "xe_bo.h"
>>> +#include "xe_map.h"
>>> +#include "xe_gsc_submit.h"
>>> +
>>> +#define HECI_MEADDRESS_HDCP 18
>>> +
>>> +struct intel_hdcp_gsc_message {
>>> +	struct xe_bo *hdcp_bo;
>>> +	u64 hdcp_cmd_in;
>>> +	u64 hdcp_cmd_out;
>>> +};
>>> +
>>> +#define HDCP_GSC_HEADER_SIZE sizeof(struct intel_gsc_mtl_header)
>>>
>>>    bool intel_hdcp_gsc_cs_required(struct xe_device *xe)
>>>    {
>>> @@ -40,19 +55,178 @@ bool intel_hdcp_gsc_check_status(struct xe_device
>> *xe)
>>>    	return ret;
>>>    }
>>>
>>> +/*This function helps allocate memory for the command that we will
>>> +send to gsc cs */ static int intel_hdcp_gsc_initialize_message(struct
>> xe_device *xe,
>>> +					     struct intel_hdcp_gsc_message
>> *hdcp_message) {
>>> +	struct xe_bo *bo = NULL;
>>> +	u64 cmd_in, cmd_out;
>>> +	int ret = 0;
>>> +
>>> +	/* allocate object of two page for HDCP command memory and store
>> it */
>>> +	xe_device_mem_access_get(xe);
>>> +	bo = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe), NULL,
>> PAGE_SIZE * 2,
>>> +				  ttm_bo_type_kernel,
>>> +				  XE_BO_CREATE_SYSTEM_BIT |
>>> +				  XE_BO_CREATE_GGTT_BIT);
>>> +
>>> +	if (IS_ERR(bo)) {
>>> +		drm_err(&xe->drm, "Failed to allocate bo for HDCP streaming
>> command!\n");
>>> +		ret = PTR_ERR(bo);
>>> +		goto out;
>>> +	}
>>> +
>>> +	cmd_in = xe_bo_ggtt_addr(bo);
>>> +	cmd_out = cmd_in + PAGE_SIZE;
>>> +	xe_map_memset(xe, &bo->vmap, 0, 0, bo->size);
>>> +
>>> +	hdcp_message->hdcp_bo = bo;
>>> +	hdcp_message->hdcp_cmd_in = cmd_in;
>>> +	hdcp_message->hdcp_cmd_out = cmd_out;
>>> +out:
>>> +	xe_device_mem_access_put(xe);
>>> +	return ret;
>>> +}
>>> +
>>> +static int intel_hdcp_gsc_hdcp2_init(struct xe_device *xe) {
>>> +	struct intel_hdcp_gsc_message *hdcp_message;
>>> +	int ret;
>>> +
>>> +	hdcp_message = kzalloc(sizeof(*hdcp_message), GFP_KERNEL);
>>> +
>>> +	if (!hdcp_message)
>>> +		return -ENOMEM;
>>> +
>>> +	/*
>>> +	 * NOTE: No need to lock the comp mutex here as it is already
>>> +	 * going to be taken before this function called
>>> +	 */
>>> +	ret = intel_hdcp_gsc_initialize_message(xe, hdcp_message);
>>> +	xe->display.hdcp.hdcp_message = hdcp_message;
>>> +
>>> +	if (ret) {
>>> +		drm_err(&xe->drm, "Could not initialize hdcp_message\n");
>>> +		kfree(hdcp_message);
>> Here you're leaving xe->display.hdcp.hdcp_message pointing to a memory
>> location that we no longer own. is that safe for the _fini function?
>>
> Would it be better to not have a kfree here if initialization fails it gets taken care of
> In finish function anyways that would be safer I presume.

We normally try to clean up immediately when things go wrong, also 
because if this failure causes the driver load to abort the _fini 
function might not get called (but not sure if this is the case here).
In this case this can be easily fixed by simply changing it to:

ret = intel_hdcp_gsc_initialize_message(xe, hdcp_message);
if (ret) {
	drm_err(&xe->drm, "Could not initialize hdcp_message\n");
	kfree(hdcp_message);
	return ret;
}

xe->display.hdcp.hdcp_message = hdcp_message;
return 0;


Which guarantees that xe->display.hdcp.hdcp_message is only set when the 
allocation exists with minimal changes to the code.

Daniele

>
>> LGTM apart from this (assuming it is going to be squashed with the next
>> patch for merge).
> Yes this will be squashed with the next patch when I send the new revision
>
> Regards,
> Suraj Kandpal
>> Daniele
>>
>>> +	}
>>> +
>>> +	return ret;
>>> +}
>>> +
>>>    int intel_hdcp_gsc_init(struct xe_device *xe)
>>>    {
>>> -	drm_dbg_kms(&xe->drm, "HDCP support not yet implemented\n");
>>> -	return -ENODEV;
>>> +	struct i915_hdcp_arbiter *data;
>>> +	int ret;
>>> +
>>> +	data = kzalloc(sizeof(*data), GFP_KERNEL);
>>> +	if (!data)
>>> +		return -ENOMEM;
>>> +
>>> +	mutex_lock(&xe->display.hdcp.hdcp_mutex);
>>> +	xe->display.hdcp.arbiter = data;
>>> +	xe->display.hdcp.arbiter->hdcp_dev = xe->drm.dev;
>>> +	xe->display.hdcp.arbiter->ops = &gsc_hdcp_ops;
>>> +	ret = intel_hdcp_gsc_hdcp2_init(xe);
>>> +	if (ret)
>>> +		kfree(data);
>>> +
>>> +	mutex_unlock(&xe->display.hdcp.hdcp_mutex);
>>> +
>>> +	return ret;
>>>    }
>>>
>>>    void intel_hdcp_gsc_fini(struct xe_device *xe)
>>>    {
>>> +	struct intel_hdcp_gsc_message *hdcp_message =
>>> +					xe->display.hdcp.hdcp_message;
>>> +
>>> +	if (!hdcp_message)
>>> +		return;
>>> +
>>> +	xe_bo_unpin_map_no_vm(hdcp_message->hdcp_bo);
>>> +	kfree(hdcp_message);
>>> +}
>>> +
>>> +static int xe_gsc_send_sync(struct xe_device *xe,
>>> +			    struct intel_hdcp_gsc_message *hdcp_message,
>>> +			    u32 msg_size_in, u32 msg_size_out,
>>> +			    u32 addr_out_off)
>>> +{
>>> +	struct xe_gt *gt = hdcp_message->hdcp_bo->tile->media_gt;
>>> +	struct iosys_map *map = &hdcp_message->hdcp_bo->vmap;
>>> +	struct xe_gsc *gsc = &gt->uc.gsc;
>>> +	int ret;
>>> +
>>> +	ret = xe_gsc_pkt_submit_kernel(gsc, hdcp_message->hdcp_cmd_in,
>> msg_size_in,
>>> +				       hdcp_message->hdcp_cmd_out,
>> msg_size_out);
>>> +	if (ret) {
>>> +		drm_err(&xe->drm, "failed to send gsc HDCP msg (%d)\n",
>> ret);
>>> +		return ret;
>>> +	}
>>> +
>>> +	if (xe_gsc_check_and_update_pending(xe, map, 0, map,
>> addr_out_off))
>>> +		return -EAGAIN;
>>> +
>>> +	ret = xe_gsc_read_out_header(xe, map, addr_out_off,
>>> +				     sizeof(struct hdcp_cmd_header), NULL);
>>> +
>>> +	return ret;
>>>    }
>>>
>>>    ssize_t intel_hdcp_gsc_msg_send(struct xe_device *xe, u8 *msg_in,
>>>    				size_t msg_in_len, u8 *msg_out,
>>>    				size_t msg_out_len)
>>>    {
>>> -	return -ENODEV;
>>> +	const size_t max_msg_size = PAGE_SIZE - HDCP_GSC_HEADER_SIZE;
>>> +	struct intel_hdcp_gsc_message *hdcp_message;
>>> +	u64 host_session_id;
>>> +	u32 msg_size_in, msg_size_out;
>>> +	u32 addr_out_off, addr_in_wr_off = 0;
>>> +	int ret, tries = 0;
>>> +
>>> +	if (msg_in_len > max_msg_size || msg_out_len > max_msg_size) {
>>> +		ret = -ENOSPC;
>>> +		goto out;
>>> +	}
>>> +
>>> +	msg_size_in = msg_in_len + HDCP_GSC_HEADER_SIZE;
>>> +	msg_size_out = msg_out_len + HDCP_GSC_HEADER_SIZE;
>>> +	hdcp_message = xe->display.hdcp.hdcp_message;
>>> +	addr_out_off = PAGE_SIZE;
>>> +
>>> +	host_session_id = xe_gsc_create_host_session_id();
>>> +	xe_device_mem_access_get(xe);
>>> +	addr_in_wr_off = xe_gsc_emit_header(xe, &hdcp_message-
>>> hdcp_bo->vmap,
>>> +					    addr_in_wr_off,
>> HECI_MEADDRESS_HDCP,
>>> +					    host_session_id, msg_in_len);
>>> +	xe_map_memcpy_to(xe, &hdcp_message->hdcp_bo->vmap,
>> addr_in_wr_off,
>>> +			 msg_in, msg_in_len);
>>> +	/*
>>> +	 * Keep sending request in case the pending bit is set no need to add
>>> +	 * message handle as we are using same address hence loc. of header
>> is
>>> +	 * same and it will contain the message handle. we will send the
>> message
>>> +	 * 20 times each message 50 ms apart
>>> +	 */
>>> +	do {
>>> +		ret = xe_gsc_send_sync(xe, hdcp_message, msg_size_in,
>> msg_size_out,
>>> +				       addr_out_off);
>>> +
>>> +		/* Only try again if gsc says so */
>>> +		if (ret != -EAGAIN)
>>> +			break;
>>> +
>>> +		msleep(50);
>>> +
>>> +	} while (++tries < 20);
>>> +
>>> +	if (ret)
>>> +		goto out;
>>> +
>>> +	xe_map_memcpy_from(xe, msg_out, &hdcp_message->hdcp_bo-
>>> vmap,
>>> +			   addr_out_off + HDCP_GSC_HEADER_SIZE,
>>> +			   msg_out_len);
>>> +
>>> +out:
>>> +	xe_device_mem_access_put(xe);
>>> +	return ret;
>>>    }
>>> diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.c
>>> b/drivers/gpu/drm/xe/xe_gsc_submit.c
>>> index 348994b271be..9a18f5667db3 100644
>>> --- a/drivers/gpu/drm/xe/xe_gsc_submit.c
>>> +++ b/drivers/gpu/drm/xe/xe_gsc_submit.c
>>> @@ -40,6 +40,21 @@ gsc_to_gt(struct xe_gsc *gsc)
>>>    	return container_of(gsc, struct xe_gt, uc.gsc);
>>>    }
>>>
>>> +/**
>>> + * xe_gsc_get_host_session_id - Creates a random 64 bit host_session
>>> +id with
>>> + * bits 56-63 masked.
>>> + *
>>> + * Returns: random host_session_id which can be used to send messages
>>> +to gsc cs  */
>>> +u64 xe_gsc_create_host_session_id(void)
>>> +{
>>> +	u64 host_session_id;
>>> +
>>> +	get_random_bytes(&host_session_id, sizeof(u64));
>>> +	host_session_id &= ~HOST_SESSION_CLIENT_MASK;
>>> +	return host_session_id;
>>> +}
>>> +
>>>    /**
>>>     * xe_gsc_emit_header - write the MTL GSC header in memory
>>>     * @xe: the Xe device
>>> diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.h
>>> b/drivers/gpu/drm/xe/xe_gsc_submit.h
>>> index 1939855031a6..1416b5745a4c 100644
>>> --- a/drivers/gpu/drm/xe/xe_gsc_submit.h
>>> +++ b/drivers/gpu/drm/xe/xe_gsc_submit.h
>>> @@ -28,4 +28,5 @@ int xe_gsc_read_out_header(struct xe_device *xe,
>>>    int xe_gsc_pkt_submit_kernel(struct xe_gsc *gsc, u64 addr_in, u32 size_in,
>>>    			     u64 addr_out, u32 size_out);
>>>
>>> +u64 xe_gsc_create_host_session_id(void);
>>>    #endif
diff mbox series

Patch

diff --git a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
index 425db3532ce5..aa8c13916bb6 100644
--- a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
+++ b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
@@ -4,12 +4,27 @@ 
  */
 
 #include <drm/drm_print.h>
+#include <linux/delay.h>
 
+#include "abi/gsc_command_header_abi.h"
 #include "intel_hdcp_gsc.h"
 #include "xe_device_types.h"
 #include "xe_gt.h"
 #include "xe_gsc_proxy.h"
 #include "xe_pm.h"
+#include "xe_bo.h"
+#include "xe_map.h"
+#include "xe_gsc_submit.h"
+
+#define HECI_MEADDRESS_HDCP 18
+
+struct intel_hdcp_gsc_message {
+	struct xe_bo *hdcp_bo;
+	u64 hdcp_cmd_in;
+	u64 hdcp_cmd_out;
+};
+
+#define HDCP_GSC_HEADER_SIZE sizeof(struct intel_gsc_mtl_header)
 
 bool intel_hdcp_gsc_cs_required(struct xe_device *xe)
 {
@@ -40,19 +55,178 @@  bool intel_hdcp_gsc_check_status(struct xe_device *xe)
 	return ret;
 }
 
+/*This function helps allocate memory for the command that we will send to gsc cs */
+static int intel_hdcp_gsc_initialize_message(struct xe_device *xe,
+					     struct intel_hdcp_gsc_message *hdcp_message)
+{
+	struct xe_bo *bo = NULL;
+	u64 cmd_in, cmd_out;
+	int ret = 0;
+
+	/* allocate object of two page for HDCP command memory and store it */
+	xe_device_mem_access_get(xe);
+	bo = xe_bo_create_pin_map(xe, xe_device_get_root_tile(xe), NULL, PAGE_SIZE * 2,
+				  ttm_bo_type_kernel,
+				  XE_BO_CREATE_SYSTEM_BIT |
+				  XE_BO_CREATE_GGTT_BIT);
+
+	if (IS_ERR(bo)) {
+		drm_err(&xe->drm, "Failed to allocate bo for HDCP streaming command!\n");
+		ret = PTR_ERR(bo);
+		goto out;
+	}
+
+	cmd_in = xe_bo_ggtt_addr(bo);
+	cmd_out = cmd_in + PAGE_SIZE;
+	xe_map_memset(xe, &bo->vmap, 0, 0, bo->size);
+
+	hdcp_message->hdcp_bo = bo;
+	hdcp_message->hdcp_cmd_in = cmd_in;
+	hdcp_message->hdcp_cmd_out = cmd_out;
+out:
+	xe_device_mem_access_put(xe);
+	return ret;
+}
+
+static int intel_hdcp_gsc_hdcp2_init(struct xe_device *xe)
+{
+	struct intel_hdcp_gsc_message *hdcp_message;
+	int ret;
+
+	hdcp_message = kzalloc(sizeof(*hdcp_message), GFP_KERNEL);
+
+	if (!hdcp_message)
+		return -ENOMEM;
+
+	/*
+	 * NOTE: No need to lock the comp mutex here as it is already
+	 * going to be taken before this function called
+	 */
+	ret = intel_hdcp_gsc_initialize_message(xe, hdcp_message);
+	xe->display.hdcp.hdcp_message = hdcp_message;
+
+	if (ret) {
+		drm_err(&xe->drm, "Could not initialize hdcp_message\n");
+		kfree(hdcp_message);
+	}
+
+	return ret;
+}
+
 int intel_hdcp_gsc_init(struct xe_device *xe)
 {
-	drm_dbg_kms(&xe->drm, "HDCP support not yet implemented\n");
-	return -ENODEV;
+	struct i915_hdcp_arbiter *data;
+	int ret;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	mutex_lock(&xe->display.hdcp.hdcp_mutex);
+	xe->display.hdcp.arbiter = data;
+	xe->display.hdcp.arbiter->hdcp_dev = xe->drm.dev;
+	xe->display.hdcp.arbiter->ops = &gsc_hdcp_ops;
+	ret = intel_hdcp_gsc_hdcp2_init(xe);
+	if (ret)
+		kfree(data);
+
+	mutex_unlock(&xe->display.hdcp.hdcp_mutex);
+
+	return ret;
 }
 
 void intel_hdcp_gsc_fini(struct xe_device *xe)
 {
+	struct intel_hdcp_gsc_message *hdcp_message =
+					xe->display.hdcp.hdcp_message;
+
+	if (!hdcp_message)
+		return;
+
+	xe_bo_unpin_map_no_vm(hdcp_message->hdcp_bo);
+	kfree(hdcp_message);
+}
+
+static int xe_gsc_send_sync(struct xe_device *xe,
+			    struct intel_hdcp_gsc_message *hdcp_message,
+			    u32 msg_size_in, u32 msg_size_out,
+			    u32 addr_out_off)
+{
+	struct xe_gt *gt = hdcp_message->hdcp_bo->tile->media_gt;
+	struct iosys_map *map = &hdcp_message->hdcp_bo->vmap;
+	struct xe_gsc *gsc = &gt->uc.gsc;
+	int ret;
+
+	ret = xe_gsc_pkt_submit_kernel(gsc, hdcp_message->hdcp_cmd_in, msg_size_in,
+				       hdcp_message->hdcp_cmd_out, msg_size_out);
+	if (ret) {
+		drm_err(&xe->drm, "failed to send gsc HDCP msg (%d)\n", ret);
+		return ret;
+	}
+
+	if (xe_gsc_check_and_update_pending(xe, map, 0, map, addr_out_off))
+		return -EAGAIN;
+
+	ret = xe_gsc_read_out_header(xe, map, addr_out_off,
+				     sizeof(struct hdcp_cmd_header), NULL);
+
+	return ret;
 }
 
 ssize_t intel_hdcp_gsc_msg_send(struct xe_device *xe, u8 *msg_in,
 				size_t msg_in_len, u8 *msg_out,
 				size_t msg_out_len)
 {
-	return -ENODEV;
+	const size_t max_msg_size = PAGE_SIZE - HDCP_GSC_HEADER_SIZE;
+	struct intel_hdcp_gsc_message *hdcp_message;
+	u64 host_session_id;
+	u32 msg_size_in, msg_size_out;
+	u32 addr_out_off, addr_in_wr_off = 0;
+	int ret, tries = 0;
+
+	if (msg_in_len > max_msg_size || msg_out_len > max_msg_size) {
+		ret = -ENOSPC;
+		goto out;
+	}
+
+	msg_size_in = msg_in_len + HDCP_GSC_HEADER_SIZE;
+	msg_size_out = msg_out_len + HDCP_GSC_HEADER_SIZE;
+	hdcp_message = xe->display.hdcp.hdcp_message;
+	addr_out_off = PAGE_SIZE;
+
+	host_session_id = xe_gsc_create_host_session_id();
+	xe_device_mem_access_get(xe);
+	addr_in_wr_off = xe_gsc_emit_header(xe, &hdcp_message->hdcp_bo->vmap,
+					    addr_in_wr_off, HECI_MEADDRESS_HDCP,
+					    host_session_id, msg_in_len);
+	xe_map_memcpy_to(xe, &hdcp_message->hdcp_bo->vmap, addr_in_wr_off,
+			 msg_in, msg_in_len);
+	/*
+	 * Keep sending request in case the pending bit is set no need to add
+	 * message handle as we are using same address hence loc. of header is
+	 * same and it will contain the message handle. we will send the message
+	 * 20 times each message 50 ms apart
+	 */
+	do {
+		ret = xe_gsc_send_sync(xe, hdcp_message, msg_size_in, msg_size_out,
+				       addr_out_off);
+
+		/* Only try again if gsc says so */
+		if (ret != -EAGAIN)
+			break;
+
+		msleep(50);
+
+	} while (++tries < 20);
+
+	if (ret)
+		goto out;
+
+	xe_map_memcpy_from(xe, msg_out, &hdcp_message->hdcp_bo->vmap,
+			   addr_out_off + HDCP_GSC_HEADER_SIZE,
+			   msg_out_len);
+
+out:
+	xe_device_mem_access_put(xe);
+	return ret;
 }
diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.c b/drivers/gpu/drm/xe/xe_gsc_submit.c
index 348994b271be..9a18f5667db3 100644
--- a/drivers/gpu/drm/xe/xe_gsc_submit.c
+++ b/drivers/gpu/drm/xe/xe_gsc_submit.c
@@ -40,6 +40,21 @@  gsc_to_gt(struct xe_gsc *gsc)
 	return container_of(gsc, struct xe_gt, uc.gsc);
 }
 
+/**
+ * xe_gsc_get_host_session_id - Creates a random 64 bit host_session id with
+ * bits 56-63 masked.
+ *
+ * Returns: random host_session_id which can be used to send messages to gsc cs
+ */
+u64 xe_gsc_create_host_session_id(void)
+{
+	u64 host_session_id;
+
+	get_random_bytes(&host_session_id, sizeof(u64));
+	host_session_id &= ~HOST_SESSION_CLIENT_MASK;
+	return host_session_id;
+}
+
 /**
  * xe_gsc_emit_header - write the MTL GSC header in memory
  * @xe: the Xe device
diff --git a/drivers/gpu/drm/xe/xe_gsc_submit.h b/drivers/gpu/drm/xe/xe_gsc_submit.h
index 1939855031a6..1416b5745a4c 100644
--- a/drivers/gpu/drm/xe/xe_gsc_submit.h
+++ b/drivers/gpu/drm/xe/xe_gsc_submit.h
@@ -28,4 +28,5 @@  int xe_gsc_read_out_header(struct xe_device *xe,
 int xe_gsc_pkt_submit_kernel(struct xe_gsc *gsc, u64 addr_in, u32 size_in,
 			     u64 addr_out, u32 size_out);
 
+u64 xe_gsc_create_host_session_id(void);
 #endif