6.1-stable review patch. If anyone has any objections, please let me know.
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From: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com
[ Upstream commit fcf226f1f7083cba76af47bf8dd764b68b149cd2 ]
As specified in this driver, the context banks are 0x1000 apart but on some SoCs the context number does not necessarily match this logic, hence we end up using the wrong ASID: keeping in mind that this IOMMU implementation relies heavily on SCM (TZ) calls, it is mandatory that we communicate the right context number.
Since this is all about how context banks are mapped in firmware, which may be board dependent (as a different firmware version may eventually change the expected context bank numbers), introduce a new property "qcom,ctx-asid": when found, the ASID will be forced as read from the devicetree.
When "qcom,ctx-asid" is not found, this driver retains the previous behavior as to avoid breaking older devicetrees or systems that do not require forcing ASID numbers.
Signed-off-by: Marijn Suijten marijn.suijten@somainline.org [Marijn: Rebased over next-20221111] Signed-off-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Reviewed-by: Konrad Dybcio konrad.dybcio@linaro.org Link: https://lore.kernel.org/r/20230622092742.74819-3-angelogioacchino.delregno@c... Signed-off-by: Will Deacon will@kernel.org Stable-dep-of: 6a3908ce56e6 ("iommu/qcom: fix device leak on of_xlate()") Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)
--- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c +++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c @@ -563,7 +563,8 @@ static int qcom_iommu_of_xlate(struct de * index into qcom_iommu->ctxs: */ if (WARN_ON(asid < 1) || - WARN_ON(asid > qcom_iommu->num_ctxs)) { + WARN_ON(asid > qcom_iommu->num_ctxs) || + WARN_ON(qcom_iommu->ctxs[asid - 1] == NULL)) { put_device(&iommu_pdev->dev); return -EINVAL; } @@ -650,7 +651,8 @@ free_mem:
static int get_asid(const struct device_node *np) { - u32 reg; + u32 reg, val; + int asid;
/* read the "reg" property directly to get the relative address * of the context bank, and calculate the asid from that: @@ -658,7 +660,17 @@ static int get_asid(const struct device_ if (of_property_read_u32_index(np, "reg", 0, ®)) return -ENODEV;
- return reg / 0x1000; /* context banks are 0x1000 apart */ + /* + * Context banks are 0x1000 apart but, in some cases, the ASID + * number doesn't match to this logic and needs to be passed + * from the DT configuration explicitly. + */ + if (!of_property_read_u32(np, "qcom,ctx-asid", &val)) + asid = val; + else + asid = reg / 0x1000; + + return asid; }
static int qcom_iommu_ctx_probe(struct platform_device *pdev)