Commit ecfadb6e authored by Will Deacon's avatar Will Deacon Committed by Joerg Roedel
Browse files

iommu/arm-smmu: Simplify VMID and ASID allocation 



We only use ASIDs and VMIDs to identify individual stage-1 and stage-2
context-banks respectively, so rather than allocate these separately
from the context-banks, just calculate them based on the context bank
index.

Note that VMIDs are offset by 1, since VMID 0 is reserved for stage-1.
This doesn't cause us any issues with the numberspaces, since the
maximum number of context banks is half the minimum number of VMIDs.

Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarJoerg Roedel <joro@8bytes.org>
parent 1463fe44

drivers/iommu/arm-smmu.c

+11 −22
Original line number Diff line number Diff line
@@ -56,9 +56,6 @@ 
/* Maximum number of mapping groups per SMMU */

#define ARM_SMMU_MAX_SMRS		128



/* Number of VMIDs per SMMU */

#define ARM_SMMU_NUM_VMIDS		256



/* SMMU global address space */

#define ARM_SMMU_GR0(smmu)		((smmu)->base)

#define ARM_SMMU_GR1(smmu)		((smmu)->base + (smmu)->pagesize)
@@ -369,21 +366,21 @@ struct arm_smmu_device { 
	u32				num_context_irqs;

	unsigned int			*irqs;



	DECLARE_BITMAP(vmid_map, ARM_SMMU_NUM_VMIDS);



	struct list_head		list;

	struct rb_root			masters;

};



struct arm_smmu_cfg {

	struct arm_smmu_device		*smmu;

	u8				vmid;

	u8				cbndx;

	u8				irptndx;

	u32				cbar;

	pgd_t				*pgd;

};



#define ARM_SMMU_CB_ASID(cfg)		((cfg)->cbndx)

#define ARM_SMMU_CB_VMID(cfg)		((cfg)->cbndx + 1)



struct arm_smmu_domain {

	/*

	 * A domain can span across multiple, chained SMMUs and requires
@@ -545,10 +542,12 @@ static void arm_smmu_tlb_inv_context(struct arm_smmu_cfg *cfg) 


	if (stage1) {

		base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);

		writel_relaxed(cfg->vmid, base + ARM_SMMU_CB_S1_TLBIASID);

		writel_relaxed(ARM_SMMU_CB_ASID(cfg),

			       base + ARM_SMMU_CB_S1_TLBIASID);

	} else {

		base = ARM_SMMU_GR0(smmu);

		writel_relaxed(cfg->vmid, base + ARM_SMMU_GR0_TLBIVMID);

		writel_relaxed(ARM_SMMU_CB_VMID(cfg),

			       base + ARM_SMMU_GR0_TLBIVMID);

	}



	arm_smmu_tlb_sync(smmu);
@@ -650,7 +649,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain) 
	if (stage1)

		reg |= (CBAR_S1_MEMATTR_WB << CBAR_S1_MEMATTR_SHIFT);

	else

		reg |= root_cfg->vmid << CBAR_VMID_SHIFT;

		reg |= ARM_SMMU_CB_VMID(root_cfg) << CBAR_VMID_SHIFT;

	writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(root_cfg->cbndx));



	if (smmu->version > 1) {
@@ -715,7 +714,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain) 
	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_LO);

	reg = (phys_addr_t)__pa(root_cfg->pgd) >> 32;

	if (stage1)

		reg |= root_cfg->vmid << TTBRn_HI_ASID_SHIFT;

		reg |= ARM_SMMU_CB_ASID(root_cfg) << TTBRn_HI_ASID_SHIFT;

	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_HI);



	/*
@@ -807,12 +806,6 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain, 
		return -ENODEV;

	}



	/* VMID zero is reserved for stage-1 mappings */

	ret = __arm_smmu_alloc_bitmap(smmu->vmid_map, 1, ARM_SMMU_NUM_VMIDS);

	if (IS_ERR_VALUE(ret))

		return ret;



	root_cfg->vmid = ret;

	if (smmu->features & ARM_SMMU_FEAT_TRANS_NESTED) {

		/*

		 * We will likely want to change this if/when KVM gets
@@ -831,10 +824,9 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain, 
	ret = __arm_smmu_alloc_bitmap(smmu->context_map, start,

				      smmu->num_context_banks);

	if (IS_ERR_VALUE(ret))

		goto out_free_vmid;

		return ret;



	root_cfg->cbndx = ret;



	if (smmu->version == 1) {

		root_cfg->irptndx = atomic_inc_return(&smmu->irptndx);

		root_cfg->irptndx %= smmu->num_context_irqs;
@@ -858,8 +850,6 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain, 


out_free_context:

	__arm_smmu_free_bitmap(smmu->context_map, root_cfg->cbndx);

out_free_vmid:

	__arm_smmu_free_bitmap(smmu->vmid_map, root_cfg->vmid);

	return ret;

}
@@ -884,7 +874,6 @@ static void arm_smmu_destroy_domain_context(struct iommu_domain *domain) 
		free_irq(irq, domain);

	}



	__arm_smmu_free_bitmap(smmu->vmid_map, root_cfg->vmid);

	__arm_smmu_free_bitmap(smmu->context_map, root_cfg->cbndx);

}
@@ -1936,7 +1925,7 @@ static int arm_smmu_device_remove(struct platform_device *pdev) 
		of_node_put(master->of_node);

	}



	if (!bitmap_empty(smmu->vmid_map, ARM_SMMU_NUM_VMIDS))

	if (!bitmap_empty(smmu->context_map, ARM_SMMU_MAX_CBS))

		dev_err(dev, "removing device with active domains!\n");



	for (i = 0; i < smmu->num_global_irqs; ++i)

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