| Message ID | 20240527-shm-bridge-v10-13-ce7afaa58d3a@linaro.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | firmware: qcom: implement support for and enable SHM bridge | expand |
On Mon, May 27, 2024 at 02:55:03PM +0200, Bartosz Golaszewski wrote: > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> > > 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> > --- > drivers/firmware/qcom/qcom_scm.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c > index c82957727650..86e26f17ca19 100644 > --- a/drivers/firmware/qcom/qcom_scm.c > +++ b/drivers/firmware/qcom/qcom_scm.c > @@ -583,6 +583,13 @@ 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 Linus so we must not do it ourselves hence Linux > + * 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); > > -- > 2.43.0 >
On Fri, Jun 21, 2024 at 12:54 AM Elliot Berman <quic_eberman@quicinc.com> wrote: > > On Mon, May 27, 2024 at 02:55:03PM +0200, Bartosz Golaszewski wrote: > > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> > > > > 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> > > --- > > drivers/firmware/qcom/qcom_scm.c | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c > > index c82957727650..86e26f17ca19 100644 > > --- a/drivers/firmware/qcom/qcom_scm.c > > +++ b/drivers/firmware/qcom/qcom_scm.c > > @@ -583,6 +583,13 @@ 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 Linus so we must not do it ourselves hence > Linux Can this be fixed when applying? I don't think there's anything else that warrants a respin. Bart > > + * 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); > > > > -- > > 2.43.0 > >
diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c index c82957727650..86e26f17ca19 100644 --- a/drivers/firmware/qcom/qcom_scm.c +++ b/drivers/firmware/qcom/qcom_scm.c @@ -583,6 +583,13 @@ 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 Linus 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);