[PATCH v3 00/11] Add mediate-drm secure flow for SVP

Jason-JH.Lin jason-jh.lin at mediatek.com
Sat Dec 23 10:29:21 PST 2023


From: Jason-jh Lin <jason-jh.lin at mediatek.corp-partner.google.com>

Memory Definitions:
secure memory - Memory allocated in the TEE (Trusted Execution
Environment) which is inaccessible in the REE (Rich Execution
Environment, i.e. linux kernel/userspace).
secure handle - Integer value which acts as reference to 'secure
memory'. Used in communication between TEE and REE to reference
'secure memory'.
secure buffer - 'secure memory' that is used to store decrypted,
compressed video or for other general purposes in the TEE.
secure surface - 'secure memory' that is used to store graphic buffers.

Memory Usage in SVP:
The overall flow of SVP starts with encrypted video coming in from an
outside source into the REE. The REE will then allocate a 'secure
buffer' and send the corresponding 'secure handle' along with the
encrypted, compressed video data to the TEE. The TEE will then decrypt
the video and store the result in the 'secure buffer'. The REE will
then allocate a 'secure surface'. The REE will pass the 'secure
handles' for both the 'secure buffer' and 'secure surface' into the
TEE for video decoding. The video decoder HW will then decode the
contents of the 'secure buffer' and place the result in the 'secure
surface'. The REE will then attach the 'secure surface' to the overlay
plane for rendering of the video.

Everything relating to ensuring security of the actual contents of the
'secure buffer' and 'secure surface' is out of scope for the REE and
is the responsibility of the TEE.

DRM driver handles allocation of gem objects that are backed by a 'secure
surface' and for displaying a 'secure surface' on the overlay plane.
This introduces a new flag for object creation called
DRM_MTK_GEM_CREATE_ENCRYPTED which indicates it should be a 'secure
surface'. All changes here are in MediaTek specific code.
---
TODO:
1) Remove get sec larb port interface in ddp_comp, ovl and ovl_adaptor.
2) Verify instruction for enabling/disabling dapc and larb port in TEE
   drop the sec_engine flags in normal world and.
3) Move DISP_REG_OVL_SECURE setting to secure world for mtk_disp_ovl.c.
4) Change the parameter register address in mtk_ddp_sec_write()
   from "u32 addr" to "struct cmdq_client_reg *cmdq_reg".
5) Implement setting mmsys routing table in the secure world series.
---
Based on 5 series and 1 patch:
[1] v3 dma-buf: heaps: Add MediaTek secure heap
- https://patchwork.kernel.org/project/linux-mediatek/list/?series=809023
[2] v3 add driver to support secure video decoder
- https://patchwork.kernel.org/project/linux-mediatek/list/?series=807308
[3] v4 soc: mediatek: Add register definitions for GCE
- https://patchwork.kernel.org/project/linux-mediatek/patch/20231212121957.19231-2-shawn.sung@mediatek.com/
[4] v2 Add CMDQ driver support for mt8188
- https://patchwork.kernel.org/project/linux-mediatek/list/?series=810302
[5] Add mediatek,gce-events definition to mediatek,gce-mailbox bindings
- https://patchwork.kernel.org/project/linux-mediatek/list/?series=810938
[6] v3 Add CMDQ secure driver for SVP
- https://patchwork.kernel.org/project/linux-mediatek/list/?series=812379
---
Change in v3:
1. fix kerneldoc problems
2. fix typo in title and commit message
3. adjust naming for secure variable
4. add the missing part for is_suecure plane implementation
5. use BIT_ULL macro to replace bit shifting
6. move modification of ovl_adaptor part to the correct patch
7. add TODO list in commit message
8. add commit message for using share memory to store execute count

Change in v2:

1. remove the DRIVER_RDNDER flag for mtk_drm_ioctl
2. move cmdq_insert_backup_cookie into client driver
3. move secure gce node define from mt8195-cherry.dtsi to mt8195.dtsi
---
CK Hu (1):
  drm/mediatek: Add interface to allocate MediaTek GEM buffer.

Jason-JH.Lin (10):
  drm/mediatek/uapi: Add DRM_MTK_GEM_CREATE_ENCRYPTED flag
  drm/mediatek: Add secure buffer control flow to mtk_drm_gem
  drm/mediatek: Add secure identify flag and funcution to mtk_drm_plane
  drm/mediatek: Add mtk_ddp_sec_write to config secure buffer info
  drm/mediatek: Add get_sec_port interface to mtk_ddp_comp
  drm/mediatek: Add secure layer config support for ovl
  drm/mediatek: Add secure layer config support for ovl_adaptor
  drm/mediatek: Add secure flow support to mediatek-drm
  drm/mediatek: Add cmdq_insert_backup_cookie before secure pkt finalize
  arm64: dts: mt8195: Add secure mbox settings for vdosys

 arch/arm64/boot/dts/mediatek/mt8195.dtsi      |   6 +-
 drivers/gpu/drm/mediatek/mtk_disp_drv.h       |   3 +
 drivers/gpu/drm/mediatek/mtk_disp_ovl.c       |  31 +-
 .../gpu/drm/mediatek/mtk_disp_ovl_adaptor.c   |  15 +
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c       | 274 +++++++++++++++++-
 drivers/gpu/drm/mediatek/mtk_drm_crtc.h       |   1 +
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c   |  30 ++
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h   |  14 +
 drivers/gpu/drm/mediatek/mtk_drm_drv.c        |  13 +
 drivers/gpu/drm/mediatek/mtk_drm_gem.c        | 122 ++++++++
 drivers/gpu/drm/mediatek/mtk_drm_gem.h        |  16 +
 drivers/gpu/drm/mediatek/mtk_drm_plane.c      |  26 ++
 drivers/gpu/drm/mediatek/mtk_drm_plane.h      |   2 +
 drivers/gpu/drm/mediatek/mtk_mdp_rdma.c       |  11 +-
 drivers/gpu/drm/mediatek/mtk_mdp_rdma.h       |   2 +
 include/uapi/drm/mediatek_drm.h               |  59 ++++
 16 files changed, 607 insertions(+), 18 deletions(-)
 create mode 100644 include/uapi/drm/mediatek_drm.h

-- 
2.18.0




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