iommu/arm-smmu: Prepare for the adreno-smmu implementation

Do a bit of prep work to add the upcoming adreno-smmu implementation.

Add an hook to allow the implementation to choose which context banks
to allocate.

Move some of the common structs to arm-smmu.h in anticipation of them
being used by the implementations and update some of the existing hooks
to pass more information that the implementation will need.

These modifications will be used by the upcoming Adreno SMMU
implementation to identify the GPU device and properly configure it
for pagetable switching.

Co-developed-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>

3 files changed, 73 insertions, 55 deletions

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c
index a9861dcd0884..88f17cc33023 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c
@@ -69,7 +69,7 @@ static int cavium_cfg_probe(struct arm_smmu_device *smmu)
 }
 
 static int cavium_init_context(struct arm_smmu_domain *smmu_domain,
-		struct io_pgtable_cfg *pgtbl_cfg)
+		struct io_pgtable_cfg *pgtbl_cfg, struct device *dev)
 {
 	struct cavium_smmu *cs = container_of(smmu_domain->smmu,
 					      struct cavium_smmu, smmu);
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 8e884e58f208..dad7fa86fbd4 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -65,41 +65,10 @@ module_param(disable_bypass, bool, S_IRUGO);
 MODULE_PARM_DESC(disable_bypass,
 	"Disable bypass streams such that incoming transactions from devices that are not attached to an iommu domain will report an abort back to the device and will not be allowed to pass through the SMMU.");
 
-struct arm_smmu_s2cr {
-	struct iommu_group		*group;
-	int				count;
-	enum arm_smmu_s2cr_type		type;
-	enum arm_smmu_s2cr_privcfg	privcfg;
-	u8				cbndx;
-};
-
 #define s2cr_init_val (struct arm_smmu_s2cr){				\
 	.type = disable_bypass ? S2CR_TYPE_FAULT : S2CR_TYPE_BYPASS,	\
 }
 
-struct arm_smmu_smr {
-	u16				mask;
-	u16				id;
-	bool				valid;
-};
-
-struct arm_smmu_cb {
-	u64				ttbr[2];
-	u32				tcr[2];
-	u32				mair[2];
-	struct arm_smmu_cfg		*cfg;
-};
-
-struct arm_smmu_master_cfg {
-	struct arm_smmu_device		*smmu;
-	s16				smendx[];
-};
-#define INVALID_SMENDX			-1
-#define cfg_smendx(cfg, fw, i) \
-	(i >= fw->num_ids ? INVALID_SMENDX : cfg->smendx[i])
-#define for_each_cfg_sme(cfg, fw, i, idx) \
-	for (i = 0; idx = cfg_smendx(cfg, fw, i), i < fw->num_ids; ++i)
-
 static bool using_legacy_binding, using_generic_binding;
 
 static inline int arm_smmu_rpm_get(struct arm_smmu_device *smmu)
@@ -234,19 +203,6 @@ static int arm_smmu_register_legacy_master(struct device *dev,
 }
 #endif /* CONFIG_ARM_SMMU_LEGACY_DT_BINDINGS */
 
-static int __arm_smmu_alloc_bitmap(unsigned long *map, int start, int end)
-{
-	int idx;
-
-	do {
-		idx = find_next_zero_bit(map, end, start);
-		if (idx == end)
-			return -ENOSPC;
-	} while (test_and_set_bit(idx, map));
-
-	return idx;
-}
-
 static void __arm_smmu_free_bitmap(unsigned long *map, int idx)
 {
 	clear_bit(idx, map);
@@ -578,7 +534,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain,
 	}
 }
 
-static void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
+void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
 {
 	u32 reg;
 	bool stage1;
@@ -664,8 +620,19 @@ static void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
 	arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_SCTLR, reg);
 }
 
+static int arm_smmu_alloc_context_bank(struct arm_smmu_domain *smmu_domain,
+				       struct arm_smmu_device *smmu,
+				       struct device *dev, unsigned int start)
+{
+	if (smmu->impl && smmu->impl->alloc_context_bank)
+		return smmu->impl->alloc_context_bank(smmu_domain, smmu, dev, start);
+
+	return __arm_smmu_alloc_bitmap(smmu->context_map, start, smmu->num_context_banks);
+}
+
 static int arm_smmu_init_domain_context(struct iommu_domain *domain,
-					struct arm_smmu_device *smmu)
+					struct arm_smmu_device *smmu,
+					struct device *dev)
 {
 	int irq, start, ret = 0;
 	unsigned long ias, oas;
@@ -780,10 +747,13 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain,
 		ret = -EINVAL;
 		goto out_unlock;
 	}
-	ret = __arm_smmu_alloc_bitmap(smmu->context_map, start,
-				      smmu->num_context_banks);
-	if (ret < 0)
+
+	ret = arm_smmu_alloc_context_bank(smmu_domain, smmu, dev, start);
+	if (ret < 0) {
 		goto out_unlock;
+	}
+
+	smmu_domain->smmu = smmu;
 
 	cfg->cbndx = ret;
 	if (smmu->version < ARM_SMMU_V2) {
@@ -798,8 +768,6 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain,
 	else
 		cfg->asid = cfg->cbndx;
 
-	smmu_domain->smmu = smmu;
-
 	pgtbl_cfg = (struct io_pgtable_cfg) {
 		.pgsize_bitmap	= smmu->pgsize_bitmap,
 		.ias		= ias,
@@ -810,7 +778,7 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain,
 	};
 
 	if (smmu->impl && smmu->impl->init_context) {
-		ret = smmu->impl->init_context(smmu_domain, &pgtbl_cfg);
+		ret = smmu->impl->init_context(smmu_domain, &pgtbl_cfg, dev);
 		if (ret)
 			goto out_clear_smmu;
 	}
@@ -1194,7 +1162,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 		return ret;
 
 	/* Ensure that the domain is finalised */
-	ret = arm_smmu_init_domain_context(domain, smmu);
+	ret = arm_smmu_init_domain_context(domain, smmu, dev);
 	if (ret < 0)
 		goto rpm_put;
 
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.h b/drivers/iommu/arm/arm-smmu/arm-smmu.h
index f3e456893f28..9aaacc906597 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.h
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.h
@@ -256,6 +256,21 @@ enum arm_smmu_implementation {
 	QCOM_SMMUV2,
 };
 
+struct arm_smmu_s2cr {
+	struct iommu_group		*group;
+	int				count;
+	enum arm_smmu_s2cr_type		type;
+	enum arm_smmu_s2cr_privcfg	privcfg;
+	u8				cbndx;
+};
+
+struct arm_smmu_smr {
+	u16				mask;
+	u16				id;
+	bool				valid;
+	bool				pinned;
+};
+
 struct arm_smmu_device {
 	struct device			*dev;
 
@@ -331,6 +346,13 @@ struct arm_smmu_cfg {
 };
 #define ARM_SMMU_INVALID_IRPTNDX	0xff
 
+struct arm_smmu_cb {
+	u64				ttbr[2];
+	u32				tcr[2];
+	u32				mair[2];
+	struct arm_smmu_cfg		*cfg;
+};
+
 enum arm_smmu_domain_stage {
 	ARM_SMMU_DOMAIN_S1 = 0,
 	ARM_SMMU_DOMAIN_S2,
@@ -350,6 +372,11 @@ struct arm_smmu_domain {
 	struct iommu_domain		domain;
 };
 
+struct arm_smmu_master_cfg {
+	struct arm_smmu_device		*smmu;
+	s16				smendx[];
+};
+
 static inline u32 arm_smmu_lpae_tcr(struct io_pgtable_cfg *cfg)
 {
 	u32 tcr = FIELD_PREP(ARM_SMMU_TCR_TG0, cfg->arm_lpae_s1_cfg.tcr.tg) |
@@ -400,14 +427,36 @@ struct arm_smmu_impl {
 	int (*cfg_probe)(struct arm_smmu_device *smmu);
 	int (*reset)(struct arm_smmu_device *smmu);
 	int (*init_context)(struct arm_smmu_domain *smmu_domain,
-			struct io_pgtable_cfg *cfg);
+			struct io_pgtable_cfg *cfg, struct device *dev);
 	void (*tlb_sync)(struct arm_smmu_device *smmu, int page, int sync,
 			 int status);
 	int (*def_domain_type)(struct device *dev);
 	irqreturn_t (*global_fault)(int irq, void *dev);
 	irqreturn_t (*context_fault)(int irq, void *dev);
+	int (*alloc_context_bank)(struct arm_smmu_domain *smmu_domain,
+				  struct arm_smmu_device *smmu,
+				  struct device *dev, int start);
 };
 
+#define INVALID_SMENDX			-1
+#define cfg_smendx(cfg, fw, i) \
+	(i >= fw->num_ids ? INVALID_SMENDX : cfg->smendx[i])
+#define for_each_cfg_sme(cfg, fw, i, idx) \
+	for (i = 0; idx = cfg_smendx(cfg, fw, i), i < fw->num_ids; ++i)
+
+static inline int __arm_smmu_alloc_bitmap(unsigned long *map, int start, int end)
+{
+	int idx;
+
+	do {
+		idx = find_next_zero_bit(map, end, start);
+		if (idx == end)
+			return -ENOSPC;
+	} while (test_and_set_bit(idx, map));
+
+	return idx;
+}
+
 static inline void __iomem *arm_smmu_page(struct arm_smmu_device *smmu, int n)
 {
 	return smmu->base + (n << smmu->pgshift);
@@ -472,6 +521,7 @@ struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu);
 struct arm_smmu_device *nvidia_smmu_impl_init(struct arm_smmu_device *smmu);
 struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu);
 
+void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx);
 int arm_mmu500_reset(struct arm_smmu_device *smmu);
 
 #endif /* _ARM_SMMU_H */