Re: [PATCH 6/6] remoteproc: qcom: Enable map/unmap and SHM bridge support

[Mukesh Ojha]

On Mon, Oct 07, 2024 at 08:22:39PM +0530, Mukesh Ojha wrote:
> On Mon, Oct 07, 2024 at 10:05:08AM +0200, neil.armstrong@xxxxxxxxxx wrote:
> > On 04/10/2024 23:23, Mukesh Ojha wrote:
> > > For Qualcomm SoCs runnning with Qualcomm EL2 hypervisor(QHEE), IOMMU
> > > translation for remote processors is managed by QHEE and if the same SoC
> > > run under KVM, remoteproc carveout and devmem region should be IOMMU
> > > mapped from Linux PAS driver before remoteproc is brought up and
> > > unmapped once it is tear down and apart from this, SHM bridge also need
> > > to set up to enable memory protection on both remoteproc meta data
> > > memory as well as for the carveout region.
> > > 
> > > Enable the support required to run Qualcomm remoteprocs on non-QHEE
> > > hypervisors.
> > > 
> > > Signed-off-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
> > > ---
> > >   drivers/remoteproc/qcom_q6v5_pas.c | 41 +++++++++++++++++++++++++++++-
> > >   1 file changed, 40 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c
> > > index ac339145e072..13bd13f1b989 100644
> > > --- a/drivers/remoteproc/qcom_q6v5_pas.c
> > > +++ b/drivers/remoteproc/qcom_q6v5_pas.c
> > > @@ -122,6 +122,7 @@ struct qcom_adsp {
> > >   	struct qcom_devmem_table *devmem;
> > >   	struct qcom_tzmem_area *tzmem;
> > > +	unsigned long sid;
> > >   };
> > >   static void adsp_segment_dump(struct rproc *rproc, struct rproc_dump_segment *segment,
> > > @@ -310,9 +311,21 @@ static int adsp_start(struct rproc *rproc)
> > >   	if (ret)
> > >   		return ret;
> > > +	ret = qcom_map_unmap_carveout(rproc, adsp->mem_phys, adsp->mem_size, true, true, adsp->sid);
> > > +	if (ret) {
> > > +		dev_err(adsp->dev, "iommu mapping failed, ret: %d\n", ret);
> > > +		goto disable_irqs;
> > > +	}
> > > +
> > > +	ret = qcom_map_devmem(rproc, adsp->devmem, true, adsp->sid);
> > > +	if (ret) {
> > > +		dev_err(adsp->dev, "devmem iommu mapping failed, ret: %d\n", ret);
> > > +		goto unmap_carveout;
> > > +	}
> > > +
> > >   	ret = adsp_pds_enable(adsp, adsp->proxy_pds, adsp->proxy_pd_count);
> > >   	if (ret < 0)
> > > -		goto disable_irqs;
> > > +		goto unmap_devmem;
> > >   	ret = clk_prepare_enable(adsp->xo);
> > >   	if (ret)
> > > @@ -400,6 +413,10 @@ static int adsp_start(struct rproc *rproc)
> > >   	clk_disable_unprepare(adsp->xo);
> > >   disable_proxy_pds:
> > >   	adsp_pds_disable(adsp, adsp->proxy_pds, adsp->proxy_pd_count);
> > > +unmap_devmem:
> > > +	qcom_unmap_devmem(rproc, adsp->devmem, adsp->sid);
> > > +unmap_carveout:
> > > +	qcom_map_unmap_carveout(rproc, adsp->mem_phys, adsp->mem_size, false, true, adsp->sid);
> > >   disable_irqs:
> > >   	qcom_q6v5_unprepare(&adsp->q6v5);
> > > @@ -445,6 +462,9 @@ static int adsp_stop(struct rproc *rproc)
> > >   			dev_err(adsp->dev, "failed to shutdown dtb: %d\n", ret);
> > >   	}
> > > +	qcom_unmap_devmem(rproc, adsp->devmem, adsp->sid);
> > > +	qcom_map_unmap_carveout(rproc, adsp->mem_phys, adsp->mem_size, false, true, adsp->sid);
> > > +
> > >   	handover = qcom_q6v5_unprepare(&adsp->q6v5);
> > >   	if (handover)
> > >   		qcom_pas_handover(&adsp->q6v5);
> > > @@ -844,6 +864,25 @@ static int adsp_probe(struct platform_device *pdev)
> > >   	}
> > >   	platform_set_drvdata(pdev, adsp);
> > > +	if (of_property_present(pdev->dev.of_node, "iommus")) {
> > > +		struct of_phandle_args args;
> > > +
> > > +		ret = of_parse_phandle_with_args(pdev->dev.of_node, "iommus", "#iommu-cells", 0, &args);
> > > +		if (ret < 0)
> > > +			return ret;
> > > +
> > > +		rproc->has_iommu = true;
> > > +		adsp->sid = args.args[0];
> > > +		of_node_put(args.np);
> > > +		ret = adsp_devmem_init(adsp);
> > > +		if (ret)
> > > +			return ret;
> > 
> > Why don't you get this table from the firmware like presumably QHEE does ?
> 
> Well, AFAIK, QHEE(EL2) has this information statically present and does
> not get it from anywhere., but will confirm this twice..

Double confirmed, device memory region required by remoteproc is
statically present with QHEE.

-Mukesh

> 
> -Mukesh
>