Re: [PATCH 3/4] venus: add check to make scm calls

From: Jordan Crouse <jcrouse@codeaurora.org>
To: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Cc: Vikash Garodia <vgarodia@codeaurora.org>,
	hverkuil@xs4all.nl, mchehab@kernel.org, andy.gross@linaro.org,
	bjorn.andersson@linaro.org, linux-media@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	linux-soc@vger.kernel.org, acourbot@google.com
Subject: Re: [PATCH 3/4] venus: add check to make scm calls
Date: Tue, 22 May 2018 13:50:27 -0600	[thread overview]
Message-ID: <20180522195026.GA16550@jcrouse-lnx.qualcomm.com> (raw)
In-Reply-To: <9d5e12b1-40bd-adab-05f0-bdb209bf0174@linaro.org>

On Tue, May 22, 2018 at 04:04:51PM +0300, Stanimir Varbanov wrote:
> Hi Vikash,
> 
> On 05/17/2018 02:32 PM, Vikash Garodia wrote:
> > In order to invoke scm calls, ensure that the platform
> > has the required support to invoke the scm calls in
> > secure world. This code is in preparation to add PIL
> > functionality in venus driver.
> > 
> > Signed-off-by: Vikash Garodia <vgarodia@codeaurora.org>
> > ---
> >  drivers/media/platform/qcom/venus/hfi_venus.c | 26 +++++++++++++++++++-------
> >  1 file changed, 19 insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
> > index f61d34b..9bcce94 100644
> > --- a/drivers/media/platform/qcom/venus/hfi_venus.c
> > +++ b/drivers/media/platform/qcom/venus/hfi_venus.c
> > @@ -27,6 +27,7 @@
> >  #include "hfi_msgs.h"
> >  #include "hfi_venus.h"
> >  #include "hfi_venus_io.h"
> > +#include "firmware.h"
> >  
> >  #define HFI_MASK_QHDR_TX_TYPE		0xff000000
> >  #define HFI_MASK_QHDR_RX_TYPE		0x00ff0000
> > @@ -570,13 +571,19 @@ static int venus_halt_axi(struct venus_hfi_device *hdev)
> >  static int venus_power_off(struct venus_hfi_device *hdev)
> >  {
> >  	int ret;
> > +	void __iomem *reg_base;
> >  
> >  	if (!hdev->power_enabled)
> >  		return 0;
> >  
> > -	ret = qcom_scm_set_remote_state(TZBSP_VIDEO_STATE_SUSPEND, 0);
> > -	if (ret)
> > -		return ret;
> > +	if (qcom_scm_is_available()) {
> > +		ret = qcom_scm_set_remote_state(TZBSP_VIDEO_STATE_SUSPEND, 0);
> 
> I think it will be clearer if we abstract qcom_scm_set_remote_state to
> something like venus_set_state(SUSPEND|RESUME) in firmware.c and export
> the functions to be used here.

This specific function is a little odd because the SCM function got overloaded
and used as a hardware workaround for the adreno a5xx zap shader.

When we added it for the GPU we knew the day would come that we would need it
for Venus so we kept the name purposely generic. You can wrap if if you want
but just know that there are other non video entities out there using it.

Jordan

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