korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-11 12:28:41 +08:00
Code Issues Packages Projects Releases Wiki Activity

firmware: qcom: scm: clarify the comment in qcom_scm_pas_init_image()

Browse Source 
The "memory protection" mechanism mentioned in the comment is the SHM
Bridge. This is also the reason why we do not convert this call to using
the TZ memory allocator.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Tested-by: Andrew Halaney <ahalaney@redhat.com> # sc8280xp-lenovo-thinkpad-x13s
Tested-by: Deepti Jaggi <quic_djaggi@quicinc.com> #sa8775p-ride
Reviewed-by: Elliot Berman <quic_eberman@quicinc.com>
Link: https://lore.kernel.org/r/20240527-shm-bridge-v10-13-ce7afaa58d3a@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
This commit is contained in:
Bartosz Golaszewski 2024-05-27 14:55:03 +02:00 committed by Bjorn Andersson
parent a33b2579c8
commit dcf5bd889a
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/firmware/qcom/qcom_scm.c
View File

@ -582,6 +582,13 @@ int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size,
* During the scm call memory protection will be enabled for the meta
* data blob, so make sure it's physically contiguous, 4K aligned and
* non-cachable to avoid XPU violations.
*
* For PIL calls the hypervisor creates SHM Bridges for the blob
* buffers on behalf of Linux so we must not do it ourselves hence
* not using the TZMem allocator here.
*
* If we pass a buffer that is already part of an SHM Bridge to this
* call, it will fail.
*/
mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
GFP_KERNEL);