From mboxrd@z Thu Jan 1 00:00:00 1970 From: andreas.herrmann@calxeda.com (Andreas Herrmann) Date: Tue, 24 Sep 2013 17:06:56 +0200 Subject: [PATCH 2/7] iommu/arm-smmu: Calculate SMMU_CB_BASE from smmu register values In-Reply-To: <1380035221-11576-1-git-send-email-andreas.herrmann@calxeda.com> References: <1380035221-11576-1-git-send-email-andreas.herrmann@calxeda.com> Message-ID: <1380035221-11576-3-git-send-email-andreas.herrmann@calxeda.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Currently it is derived from smmu resource size. If the resource size is wrongly specified (e.g. too large) this leads to a miscalculation and can cause undefined behaviour when context bank registers are modified. Signed-off-by: Andreas Herrmann --- drivers/iommu/arm-smmu.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 97b764b..f5a856e 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -207,7 +207,7 @@ #define CBA2R_RW64_64BIT (1 << 0) /* Translation context bank */ -#define ARM_SMMU_CB_BASE(smmu) ((smmu)->base + ((smmu)->size >> 1)) +#define ARM_SMMU_CB_BASE(smmu) ((smmu)->cb_base) #define ARM_SMMU_CB(smmu, n) ((n) * (smmu)->pagesize) #define ARM_SMMU_CB_SCTLR 0x0 @@ -339,6 +339,7 @@ struct arm_smmu_device { struct device_node *parent_of_node; void __iomem *base; + void __iomem *cb_base; unsigned long size; unsigned long pagesize; @@ -1701,7 +1702,9 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu) /* Check that we ioremapped enough */ size = 1 << (((id >> ID1_NUMPAGENDXB_SHIFT) & ID1_NUMPAGENDXB_MASK) + 1); - size *= (smmu->pagesize << 1); + size *= smmu->pagesize; + smmu->cb_base = smmu->base + size; + size *= 2; if (smmu->size < size) dev_warn(smmu->dev, "device is 0x%lx bytes but only mapped 0x%lx!\n", -- 1.7.9.5