Re: [PATCH v11 06/11] remoteproc: mediatek: Probe multi-core SCP

TingHan Shen (沈廷翰)
2023-05-15T12:31:29Z

Hi Mathieu,

On Fri, 2023-05-12 at 11:56 -0600, Mathieu Poirier wrote:
> External email : Please do not click links or open attachments until you have verified the sender or the content.
>
>
> On Wed, May 10, 2023 at 02:37:44PM +0800, Tinghan Shen wrote:
> > The difference of single-core SCP and multi-core SCP device tree is
> > the presence of child device nodes described SCP cores. The SCP
> > driver populates the platform device and checks the child nodes
> > to identify whether it's a single-core SCP or a multi-core SCP.
> >
> > Add the remoteproc instances of multi-core SCP to the SCP cluster list.
> > When the SCP driver is removed, it cleanup resources by walking
> > through the cluster list.
> >
> > Signed-off-by: Tinghan Shen <tinghan.shen@mediatek.com>
> > ---
> > drivers/remoteproc/mtk_scp.c | 135 ++++++++++++++++++++++++++++++-----
> > 1 file changed, 117 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
> > index ff73c6dd9637..87215a0e145e 100644
> > --- a/drivers/remoteproc/mtk_scp.c
> > +++ b/drivers/remoteproc/mtk_scp.c
> > @@ -864,7 +864,8 @@ static void scp_remove_rpmsg_subdev(struct mtk_scp *scp)
> > }
> >
> > static struct mtk_scp *scp_rproc_init(struct platform_device *pdev,
> > - struct mtk_scp_of_cluster *scp_cluster)
> > + struct mtk_scp_of_cluster *scp_cluster,
> > + const struct mtk_scp_of_data *of_data)
> > {
> > struct device *dev = &pdev->dev;
> > struct device_node *np = dev->of_node;
> > @@ -887,7 +888,7 @@ static struct mtk_scp *scp_rproc_init(struct platform_device *pdev,
> > scp = rproc->priv;
> > scp->rproc = rproc;
> > scp->dev = dev;
> > - scp->data = of_device_get_match_data(dev);
> > + scp->data = of_data;
> > platform_device_add_data(pdev, &scp, sizeof(scp));
> >
> > scp->reg_base = scp_cluster->reg_base;
> > @@ -938,10 +939,6 @@ static struct mtk_scp *scp_rproc_init(struct platform_device *pdev,
> > goto remove_subdev;
> > }
> >
> > - ret = rproc_add(rproc);
> > - if (ret)
> > - goto remove_subdev;
> > -
>
> This should have been done in the previous patch.

Ok.

>
> > return scp;
> >
> > remove_subdev:
> > @@ -956,19 +953,116 @@ static struct mtk_scp *scp_rproc_init(struct platform_device *pdev,
> > return ERR_PTR(ret);
> > }
> >
> > +static void scp_rproc_free(struct mtk_scp *scp)
> > +{
> > + int i;
> > +
> > + scp_remove_rpmsg_subdev(scp);
> > + scp_ipi_unregister(scp, SCP_IPI_INIT);
> > + scp_unmap_memory_region(scp);
> > + for (i = 0; i < SCP_IPI_MAX; i++)
> > + mutex_destroy(&scp->ipi_desc[i].lock);
> > + mutex_destroy(&scp->send_lock);
> > +}
> > +
> > +static int scp_is_single_core(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct device_node *np = dev_of_node(dev);
> > + struct device_node *child;
> > +
> > + child = of_get_next_available_child(np, NULL);
> > + if (!child)
> > + return dev_err_probe(dev, -ENODEV, "No child node\n");
> > +
> > + of_node_put(child);
> > + return of_node_name_eq(child, "cros-ec-rpmsg");
> > +}
> > +
> > static int scp_cluster_init(struct platform_device *pdev)
> > {
> > - struct mtk_scp *scp;
> > + struct mtk_scp *scp, *temp;
> > struct mtk_scp_of_cluster *scp_cluster = platform_get_drvdata(pdev);
> > struct list_head *cluster = &scp_cluster->mtk_scp_cluster;
> >
> > - scp = scp_rproc_init(pdev, scp_cluster);
> > - if (IS_ERR(scp))
> > - return PTR_ERR(scp);
> > + struct device *dev = &pdev->dev;
> > + struct device_node *np = dev_of_node(dev);
> > + struct platform_device *cpdev;
> > + struct device_node *child;
> > + const struct mtk_scp_of_data **cluster_of_data;
> > + int core_id = 0;
> > + int ret;
> > +
> > + ret = scp_is_single_core(pdev);
> > + if (ret < 0)
> > + return ret;
> > +
> > + if (ret) {
> > + dev_dbg(dev, "single-core scp\n");
> > +
> > + /* When using the SCP node phandle on exported SCP APIs, the drvdata
> > + * is expected to be the mtk_scp object, and as a result, it is intended
> > + * to be overwritten for single-core SCP usage.
> > + */
>
> Is this comment still relevant?

No, I'll remove it.

>
> > + scp = scp_rproc_init(pdev, scp_cluster, of_device_get_match_data(dev));
> > + if (IS_ERR(scp))
> > + return PTR_ERR(scp);
> > +
> > + list_add_tail(&scp->elem, cluster);
>
> This is getting messy. Please add two new functions, i.e scp_add_single_core()
> and scp_add_multi_core().

Ok.

>
> > + } else {
> > + dev_dbg(dev, "multi-core scp\n");
> > +
> > + cluster_of_data = (const struct mtk_scp_of_data **)of_device_get_match_data(dev);
> > +
> > + for_each_available_child_of_node(np, child) {
> > + if (!cluster_of_data[core_id]) {
> > + ret = -EINVAL;
> > + dev_err(dev, "Not support core %d\n", core_id);
> > + of_node_put(child);
> > + goto init_fail;
> > + }
> > +
> > + cpdev = of_find_device_by_node(child);
> > + if (!cpdev) {
> > + ret = -ENODEV;
> > + dev_err(dev, "Not found platform device for core %d\n", core_id);
> > + of_node_put(child);
> > + goto init_fail;
> > + }
> > +
> > + scp = scp_rproc_init(cpdev, scp_cluster, cluster_of_data[core_id]);
> > + if (IS_ERR(scp)) {
> > + dev_err(dev, "Failed to initialize core %d rproc\n", core_id);
> > + put_device(&cpdev->dev);
> > + of_node_put(child);
> > + goto init_fail;
> > + }
> > + list_add_tail(&scp->elem, cluster);
> > + put_device(&cpdev->dev);
> > +
> > + core_id++;
> > + }
> > + }
> >
> > - list_add_tail(&scp->elem, cluster);
> > + list_for_each_entry_safe_reverse(scp, temp, cluster, elem) {
> > + ret = rproc_add(scp->rproc);
>
> Call rproc_add() in the for_each_available_child_of_node() loop above. That way
> it if fails you can call scp_rproc_free() right away and jump to init_fail to
> deal with the other cores on the list.

Ok, I'll update it in next version.

>
> > + if (ret)
> > + goto add_fail;
> > + }
> >
> > return 0;
> > +
> > +add_fail:
> > + list_for_each_entry_continue(scp, cluster, elem) {
> > + rproc_del(scp->rproc);
> > + }
> > +init_fail:
> > + list_for_each_entry_safe_reverse(scp, temp, cluster, elem) {
> > + list_del(&scp->elem);
> > + scp_rproc_free(scp);
> > + }
> > +
>
> There are a serious problems with the code in both labels above. I will let you
> think about that and I will stop here for this revision.
>
> Mathieu

May be the problem is the possible null access of *scp?
Or, the resources bound with cpdev should be released at here?

>
> > + return ret;
> > }
> >
> > static int scp_probe(struct platform_device *pdev)
> > @@ -1005,6 +1099,10 @@ static int scp_probe(struct platform_device *pdev)
> > INIT_LIST_HEAD(&scp_cluster->mtk_scp_cluster);
> > platform_set_drvdata(pdev, scp_cluster);
> >
> > + ret = devm_of_platform_populate(dev);
> > + if (ret)
> > + return dev_err_probe(dev, ret, "Failed to populate platform devices\n");
> > +
> > ret = scp_cluster_init(pdev);
> > if (ret)
> > return ret;
> > @@ -1016,17 +1114,11 @@ static int scp_remove(struct platform_device *pdev)
> > {
> > struct mtk_scp_of_cluster *scp_cluster = platform_get_drvdata(pdev);
> > struct mtk_scp *scp, *temp;
> > - int i;
> >
> > list_for_each_entry_safe_reverse(scp, temp, &scp_cluster->mtk_scp_cluster, elem) {
> > list_del(&scp->elem);
> > rproc_del(scp->rproc);
> > - scp_remove_rpmsg_subdev(scp);
> > - scp_ipi_unregister(scp, SCP_IPI_INIT);
> > - scp_unmap_memory_region(scp);
> > - for (i = 0; i < SCP_IPI_MAX; i++)
> > - mutex_destroy(&scp->ipi_desc[i].lock);
> > - mutex_destroy(&scp->send_lock);
> > + scp_rproc_free(scp);
> > }
> >
> > return 0;
> > @@ -1106,12 +1198,19 @@ static const struct mtk_scp_of_data mt8195_of_data_c1 = {
> > .host_to_scp_int_bit = MT8195_CORE1_HOST_IPC_INT_BIT,
> > };
> >
> > +static const struct mtk_scp_of_data *mt8195_of_data_cores[] = {
> > + &mt8195_of_data,
> > + &mt8195_of_data_c1,
> > + NULL
> > +};
> > +
> > static const struct of_device_id mtk_scp_of_match[] = {
> > { .compatible = "mediatek,mt8183-scp", .data = &mt8183_of_data },
> > { .compatible = "mediatek,mt8186-scp", .data = &mt8186_of_data },
> > { .compatible = "mediatek,mt8188-scp", .data = &mt8188_of_data },
> > { .compatible = "mediatek,mt8192-scp", .data = &mt8192_of_data },
> > { .compatible = "mediatek,mt8195-scp", .data = &mt8195_of_data },
> > + { .compatible = "mediatek,mt8195-scp-dual", .data = &mt8195_of_data_cores },
> > {},
> > };
> > MODULE_DEVICE_TABLE(of, mtk_scp_of_match);
> > --
> > 2.18.0
> >

--
Best regards,
TingHan