[PATCH v10 03/13] iommu/arm-smmu: Add implementation hooks to configure contexts

[Jordan Crouse]

Add a new hook to allow implementations to implement their own context
bank allocation scheme and update the existing init_context function to
take the device pointer.

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

Signed-off-by: Jordan Crouse <jcrouse at codeaurora.org>
---

 drivers/iommu/arm-smmu-impl.c |  2 +-
 drivers/iommu/arm-smmu.c      | 46 ++++++++++++-----------------------
 drivers/iommu/arm-smmu.h      | 28 ++++++++++++++++++++-
 3 files changed, 44 insertions(+), 32 deletions(-)

diff --git a/drivers/iommu/arm-smmu-impl.c b/drivers/iommu/arm-smmu-impl.c
index a20e426d81ac..b71b14685cc9 100644
--- a/drivers/iommu/arm-smmu-impl.c
+++ b/drivers/iommu/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-smmu.c b/drivers/iommu/arm-smmu.c
index 8798428a4c8d..fff536a44faa 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -93,16 +93,6 @@ struct arm_smmu_cb {
 	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)
@@ -237,19 +227,6 @@ 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);
@@ -668,7 +645,8 @@ static void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx)
 }
 
 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;
@@ -782,10 +760,20 @@ 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_domain->smmu = smmu;
+
+	if (smmu->impl && smmu->impl->alloc_context_bank)
+		ret = smmu->impl->alloc_context_bank(smmu_domain, dev,
+				start, smmu->num_context_banks);
+	else
+		ret = __arm_smmu_alloc_bitmap(smmu->context_map, start,
 				      smmu->num_context_banks);
-	if (ret < 0)
+
+	if (ret < 0) {
+		smmu_domain->smmu = NULL;
 		goto out_unlock;
+	}
 
 	cfg->cbndx = ret;
 	if (smmu->version < ARM_SMMU_V2) {
@@ -800,8 +788,6 @@ 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,
@@ -812,7 +798,7 @@ 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;
 	}
@@ -1190,7 +1176,7 @@ 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-smmu.h b/drivers/iommu/arm-smmu.h
index 5f2de20e883b..d10d745a0290 100644
--- a/drivers/iommu/arm-smmu.h
+++ b/drivers/iommu/arm-smmu.h
@@ -347,6 +347,11 @@ 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) |
@@ -397,12 +402,33 @@ 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);
+	int (*alloc_context_bank)(struct arm_smmu_domain *smmu_domain,
+			struct device *dev, int start, int max);
 };
 
+#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);
-- 
2.25.1