On 2/2/2024 12:37 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.
Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
---
drivers/gpu/drm/xe/display/xe_hdcp_gsc.c | 188 ++++++++++++++++++++++-
1 file changed, 184 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
index 0f11a39333e2..eca941d7b281 100644
--- a/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
+++ b/drivers/gpu/drm/xe/display/xe_hdcp_gsc.c
@@ -3,8 +3,24 @@
* Copyright 2023, Intel Corporation.
*/
+#include "abi/gsc_command_header_abi.h"
My original idea was for the users to not include this header and rely
on the size provided by the emit functions. I see you use the check the
input size, which I didn't do on the proxy side because the buffer is
sized to be big enough for all possible commands. Overall not a blocker,
just consider the option.
#include "i915_drv.h"
Do you actually need i915_drv.h? You shouldn't be using any structure
from i915 here. If you just need it for the pointers to struct
drm_i915_private, just add a forward declaration for the structure.
#include "intel_hdcp_gsc.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 HOST_SESSION_CLIENT_MASK GENMASK_ULL(63, 56)
+#define HDCP_GSC_MESSAGE_SIZE sizeof(struct intel_hdcp_gsc_message)
this define is unused. Also, intel_hdcp_gsc_message is not the actual
message, but just contains a pointer to the object that holds the message.
+#define HDCP_GSC_HEADER_SIZE sizeof(struct intel_gsc_mtl_header)
bool intel_hdcp_gsc_cs_required(struct drm_i915_private *i915)
{
@@ -13,22 +29,186 @@ bool intel_hdcp_gsc_cs_required(struct drm_i915_private *i915)
bool intel_hdcp_gsc_check_status(struct drm_i915_private *i915)
{
- return false;
+ return true;
Shouldn't you actually do a check in here?
+}
+
+/*This function helps allocate memory for the command that we will send to gsc cs */
+static int intel_hdcp_gsc_initialize_message(struct drm_i915_private *i915,
Having a drm_i915_private here that is actually an xe_device is really
weird. I understand that the aim is to re-use most of the display code
from i915, but if you need to different back-ends maybe just have the
function accept a void pointer and then internally cast it to
drm_i915_private or xe_device based on the driver, or use struct
intel_display and cast it back to i915 or Xe with a container_of. I'll
leave the final comment on this to someone that has more understanding
than me of what's going on on the display side of things.
+ struct intel_hdcp_gsc_message *hdcp_message)
+{
+ struct xe_bo *bo = NULL;
+ u64 cmd_in, cmd_out;
+ int err, ret = 0;
+
+ /* allocate object of two page for HDCP command memory and store it */
+
+ xe_device_mem_access_get(i915);
+ bo = xe_bo_create_pin_map(i915, xe_device_get_root_tile(i915), NULL, PAGE_SIZE * 2,
+ ttm_bo_type_kernel,
+ XE_BO_CREATE_SYSTEM_BIT |
+ XE_BO_CREATE_GGTT_BIT);
+
+ if (IS_ERR(bo)) {
+ drm_err(&i915->drm, "Failed to allocate bo for HDCP streaming command!\n");
+ ret = err;
+ goto out;
+ }
+
+ cmd_in = xe_bo_ggtt_addr(bo);
+
+ if (iosys_map_is_null(&bo->vmap)) {
this can't happen, if the bo fails to map then xe_bo_create_pin_map will
return an error.
+ drm_err(&i915->drm, "Failed to map gsc message page!\n");
+ ret = PTR_ERR(&bo->vmap);
+ goto out;
+ }
+
+ cmd_out = cmd_in + PAGE_SIZE;
+
+ xe_map_memset(i915, &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(i915);
+ return ret;
+}
+
+static int intel_hdcp_gsc_hdcp2_init(struct drm_i915_private *i915)
+{
+ 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
+ */
+ i915->display.hdcp.hdcp_message = hdcp_message;
+ ret = intel_hdcp_gsc_initialize_message(i915, hdcp_message);
+
+ if (ret)
+ drm_err(&i915->drm, "Could not initialize hdcp_message\n");
Don't you need a kfree in this error path? alternatively you can use
drmm_kzalloc so that it is always automatically freed.
+
+ return ret;
}
int intel_hdcp_gsc_init(struct drm_i915_private *i915)
{
- drm_info(&i915->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(&i915->display.hdcp.hdcp_mutex);
+ i915->display.hdcp.arbiter = data;
+ i915->display.hdcp.arbiter->hdcp_dev = i915->drm.dev;
+ i915->display.hdcp.arbiter->ops = &gsc_hdcp_ops;
Does this patch compile on its own? As far as I can see gsc_hdcp_ops is
added in the next patch.
+ ret = intel_hdcp_gsc_hdcp2_init(i915);
+ mutex_unlock(&i915->display.hdcp.hdcp_mutex);
+
+ return ret;
Here as well missing the kfree on error
}
void intel_hdcp_gsc_fini(struct drm_i915_private *i915)
{
+ struct intel_hdcp_gsc_message *hdcp_message =
+ i915->display.hdcp.hdcp_message;
+
+ xe_bo_unpin_map_no_vm(hdcp_message->hdcp_bo);
+ kfree(hdcp_message);
+
}
+static int xe_gsc_send_sync(struct drm_i915_private *i915,
+ struct intel_hdcp_gsc_message *hdcp_message,
+ u32 msg_size_in, u32 msg_size_out,
+ u32 addr_in_off, u32 addr_out_off,
Those 2 variables are unused.
+ size_t msg_out_len)
+{
+ struct xe_gt *gt = hdcp_message->hdcp_bo->tile->media_gt;
+ struct iosys_map *map = &hdcp_message->hdcp_bo->vmap;
+ struct xe_gsc *gsc = >->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(&i915->drm, "failed to send gsc HDCP msg (%d)\n", ret);
+ return ret;
+ }
+
+ ret = xe_gsc_check_and_update_pending(i915, map, 0, map, addr_out_off);
This returns a bool, so you can call it directly inside the if statement
instead of casting the return to int.
+
+ if (ret)
+ return -EAGAIN;
+
+ ret = xe_gsc_read_out_header(i915, map, addr_out_off,
+ sizeof(struct hdcp_cmd_header), NULL);
Note that here you're only checking that the message is at least as big
as struct hdcp_cmd_header, but if there was an error and the only thing
in the message was the header it'll still pass. This links with a
comment below.
+
+ return ret;
+}
ssize_t intel_hdcp_gsc_msg_send(struct drm_i915_private *i915, 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, addr_in_off = 0, addr_out_off;
+ 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 = i915->display.hdcp.hdcp_message;
+ addr_out_off = PAGE_SIZE;
+
+ get_random_bytes(&host_session_id, sizeof(u64));
+ host_session_id = host_session_id & ~HOST_SESSION_CLIENT_MASK;
Can you move this host session code to a dedicated function in
xe_gsc_submit.c? that way we can re-use it for PXP. You can also drop
the re-definition of HOST_SESSION_CLIENT_MASK because that's already in
that file.
+ xe_device_mem_access_get(i915);
+ addr_in_off = xe_gsc_emit_header(i915, &hdcp_message->hdcp_bo->vmap,
Note that this function does not return the input offset, but the next
writable location (that's why I called it wr_offset in other code)
+ addr_in_off,
+ HECI_MEADDRESS_HDCP, host_session_id,
+ msg_in_len);
+
+ xe_map_memcpy_to(i915, &hdcp_message->hdcp_bo->vmap, addr_in_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(i915, hdcp_message, msg_size_in, msg_size_out,
+ addr_in_off, addr_out_off, msg_out_len);
+
+ /* Only try again if gsc says so */
+ if (ret != -EAGAIN)
+ break;
+
+ msleep(50);
+
+ } while (++tries < 20);
+
+ if (ret)
+ goto out;
+
+ xe_map_memcpy_from(i915, msg_out, &hdcp_message->hdcp_bo->vmap,
+ addr_out_off + HDCP_GSC_HEADER_SIZE,
+ msg_out_len);
here you are copying msg_out_len, but you haven't checked if the GSC has
actually written that much, you only checked that you had struct
hdcp_cmd_header.
Daniele
+
+out:
+ xe_device_mem_access_put(i915);
+ return ret;
}
