Re: [PATCH v10 02/13] iommu/mediatek-v1: Free the existed fwspec if the master dev already has

Em Fri, 28 Jan 2022 13:40:55 +0100 Mauro Carvalho Chehab mchehab@kernel.org escreveu:

Hi Matthias/Yong,

Are you ok if this patch gets merged via the media tree together with the remaining series, or do you prefer to apply it via SoC tree instead?

Same questions for other patches touching files outside drivers/media on this pull request:

https://patchwork.kernel.org/project/linux-mediatek/patch/7af52d61-47c7-581d...

Like those: 0004-0013-iommu-mediatek-v1-Free-the-existed-fwspec-if-the-mas.patch 0005-0013-iommu-mediatek-Return-ENODEV-if-the-device-is-NULL.patch 0006-0013-iommu-mediatek-Add-probe_defer-for-smi-larb.patch 0007-0013-iommu-mediatek-Add-device_link-between-the-consumer-.patch

Regards, Mauro

Regards, Mauro

Em Mon, 17 Jan 2022 15:04:59 +0800 Yong Wu yong.wu@mediatek.com escreveu:

...

When the iommu master device enters of_iommu_xlate, the ops may be NULL(iommu dev is defered), then it will initialize the fwspec here:

[<c0c9c5bc>] (dev_iommu_fwspec_set) from [<c06bda80>] (iommu_fwspec_init+0xbc/0xd4) [<c06bd9c4>] (iommu_fwspec_init) from [<c06c0db4>] (of_iommu_xlate+0x7c/0x12c) [<c06c0d38>] (of_iommu_xlate) from [<c06c10e8>] (of_iommu_configure+0x144/0x1e8)

BUT the mtk_iommu_v1.c only supports arm32, the probing flow still is a bit weird. We always expect create the fwspec internally. otherwise it will enter here and return fail.

static int mtk_iommu_create_mapping(struct device *dev, struct of_phandle_args *args) { ... if (!fwspec) { .... } else if (dev_iommu_fwspec_get(dev)->ops != &mtk_iommu_ops) { >>>>>>>>>>Enter here. return fail.<<<<<<<<<<<< return -EINVAL; } ... }

Thus, Free the existed fwspec if the master device already has fwspec.

This issue is reported at: https://lore.kernel.org/linux-mediatek/trinity-7d9ebdc9-4849-4d93-bfb5-429dc...

Reported-by: Frank Wunderlich frank-w@public-files.de Tested-by: Frank Wunderlich frank-w@public-files.de # BPI-R2/MT7623 Signed-off-by: Yong Wu yong.wu@mediatek.com Acked-by: Joerg Roedel jroedel@suse.de Acked-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com

---

drivers/iommu/mtk_iommu_v1.c | 9 +++++++++ 1 file changed, 9 insertions(+)

diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index be22fcf988ce..1467ba1e4417 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -425,6 +425,15 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) struct mtk_iommu_data *data; int err, idx = 0;

• /*

• * In the deferred case, free the existed fwspec.
  

• * Always initialize the fwspec internally.
  

• */
  

• if (fwspec) {

• iommu_fwspec_free(dev);
  

• fwspec = dev_iommu_fwspec_get(dev);
  

• }
• while (!of_parse_phandle_with_args(dev->of_node, "iommus", "#iommu-cells", idx, &iommu_spec)) {

Thanks, Mauro

Thanks, Mauro