iommu/arm-smmu: Abstract GR1 accesses

Introduce some register access abstractions which we will later use to
encapsulate various quirks. GR1 is the easiest page to start with.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 24b4de1..d612dda 100644 (file)
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -71,7 +71,6 @@
 
 /* SMMU global address space */
 #define ARM_SMMU_GR0(smmu)             ((smmu)->base)
-#define ARM_SMMU_GR1(smmu)             ((smmu)->base + (1 << (smmu)->pgshift))
 
 /*
  * SMMU global address space with conditional offset to access secure
@@ -250,6 +249,29 @@ struct arm_smmu_domain {
        struct iommu_domain             domain;
 };
 
+static void __iomem *arm_smmu_page(struct arm_smmu_device *smmu, int n)
+{
+       return smmu->base + (n << smmu->pgshift);
+}
+
+static u32 arm_smmu_readl(struct arm_smmu_device *smmu, int page, int offset)
+{
+       return readl_relaxed(arm_smmu_page(smmu, page) + offset);
+}
+
+static void arm_smmu_writel(struct arm_smmu_device *smmu, int page, int offset,
+                           u32 val)
+{
+       writel_relaxed(val, arm_smmu_page(smmu, page) + offset);
+}
+
+#define ARM_SMMU_GR1           1
+
+#define arm_smmu_gr1_read(s, o)                \
+       arm_smmu_readl((s), ARM_SMMU_GR1, (o))
+#define arm_smmu_gr1_write(s, o, v)    \
+       arm_smmu_writel((s), ARM_SMMU_GR1, (o), (v))
+
 struct arm_smmu_option_prop {
        u32 opt;
        const char *prop;
@@ -574,7 +596,6 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
        struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
        struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
        struct arm_smmu_device *smmu = smmu_domain->smmu;
-       void __iomem *gr1_base = ARM_SMMU_GR1(smmu);
        void __iomem *cb_base;
 
        cb_base = ARM_SMMU_CB(smmu, cfg->cbndx);
@@ -585,7 +606,7 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
 
        fsynr = readl_relaxed(cb_base + ARM_SMMU_CB_FSYNR0);
        iova = readq_relaxed(cb_base + ARM_SMMU_CB_FAR);
-       cbfrsynra = readl_relaxed(gr1_base + ARM_SMMU_GR1_CBFRSYNRA(cfg->cbndx));
+       cbfrsynra = arm_smmu_gr1_read(smmu, ARM_SMMU_GR1_CBFRSYNRA(cfg->cbndx));
 
        dev_err_ratelimited(smmu->dev,
        "Unhandled context fault: fsr=0x%x, iova=0x%08lx, fsynr=0x%x, cbfrsynra=0x%x, cb=%d\n",
@@ -676,7 +697,7 @@ static void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
        bool stage1;
        struct arm_smmu_cb *cb = &smmu->cbs[idx];
        struct arm_smmu_cfg *cfg = cb->cfg;
-       void __iomem *cb_base, *gr1_base;
+       void __iomem *cb_base;
 
        cb_base = ARM_SMMU_CB(smmu, idx);
 
@@ -686,7 +707,6 @@ static void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
                return;
        }
 
-       gr1_base = ARM_SMMU_GR1(smmu);
        stage1 = cfg->cbar != CBAR_TYPE_S2_TRANS;
 
        /* CBA2R */
@@ -699,7 +719,7 @@ static void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
                if (smmu->features & ARM_SMMU_FEAT_VMID16)
                        reg |= FIELD_PREP(CBA2R_VMID16, cfg->vmid);
 
-               writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBA2R(idx));
+               arm_smmu_gr1_write(smmu, ARM_SMMU_GR1_CBA2R(idx), reg);
        }
 
        /* CBAR */
@@ -718,7 +738,7 @@ static void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
                /* 8-bit VMIDs live in CBAR */
                reg |= FIELD_PREP(CBAR_VMID, cfg->vmid);
        }
-       writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(idx));
+       arm_smmu_gr1_write(smmu, ARM_SMMU_GR1_CBAR(idx), reg);
 
        /*
         * TCR