iommu/arm-smmu-v3: Add context descriptor tables allocators

Support for SSID will require allocating context descriptor tables. Move
the context descriptor allocation to separate functions.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 1723137..3f7248d 100644 (file)
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -552,11 +552,13 @@ struct arm_smmu_ctx_desc {
 struct arm_smmu_ctx_desc_cfg {
        __le64                          *cdtab;
        dma_addr_t                      cdtab_dma;
+       unsigned int                    num_l1_ents;
 };
 
 struct arm_smmu_s1_cfg {
        struct arm_smmu_ctx_desc_cfg    cdcfg;
        struct arm_smmu_ctx_desc        cd;
+       u8                              s1cdmax;
 };
 
 struct arm_smmu_s2_cfg {
@@ -1475,6 +1477,35 @@ static void arm_smmu_write_ctx_desc(struct arm_smmu_device *smmu,
        cdptr[3] = cpu_to_le64(cfg->cd.mair);
 }
 
+static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain)
+{
+       size_t l1size;
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
+       struct arm_smmu_ctx_desc_cfg *cdcfg = &cfg->cdcfg;
+
+       cdcfg->num_l1_ents = 1UL << cfg->s1cdmax;
+       l1size = cdcfg->num_l1_ents * (CTXDESC_CD_DWORDS << 3);
+       cdcfg->cdtab = dmam_alloc_coherent(smmu->dev, l1size, &cdcfg->cdtab_dma,
+                                          GFP_KERNEL);
+       if (!cdcfg->cdtab) {
+               dev_warn(smmu->dev, "failed to allocate context descriptor\n");
+               return -ENOMEM;
+       }
+       return 0;
+}
+
+static void arm_smmu_free_cd_tables(struct arm_smmu_domain *smmu_domain)
+{
+       struct arm_smmu_device *smmu = smmu_domain->smmu;
+       struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg.cdcfg;
+       size_t l1size = cdcfg->num_l1_ents * (CTXDESC_CD_DWORDS << 3);
+
+       dmam_free_coherent(smmu->dev, l1size, cdcfg->cdtab, cdcfg->cdtab_dma);
+       cdcfg->cdtab_dma = 0;
+       cdcfg->cdtab = NULL;
+}
+
 /* Stream table manipulation functions */
 static void
 arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
@@ -2118,11 +2149,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
                struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
 
                if (cfg->cdcfg.cdtab) {
-                       dmam_free_coherent(smmu_domain->smmu->dev,
-                                          CTXDESC_CD_DWORDS << 3,
-                                          cfg->cdcfg.cdtab,
-                                          cfg->cdcfg.cdtab_dma);
-
+                       arm_smmu_free_cd_tables(smmu_domain);
                        arm_smmu_bitmap_free(smmu->asid_map, cfg->cd.asid);
                }
        } else {
@@ -2147,15 +2174,9 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
        if (asid < 0)
                return asid;
 
-       cfg->cdcfg.cdtab = dmam_alloc_coherent(smmu->dev,
-                                              CTXDESC_CD_DWORDS << 3,
-                                              &cfg->cdcfg.cdtab_dma,
-                                              GFP_KERNEL);
-       if (!cfg->cdcfg.cdtab) {
-               dev_warn(smmu->dev, "failed to allocate context descriptor\n");
-               ret = -ENOMEM;
+       ret = arm_smmu_alloc_cd_tables(smmu_domain);
+       if (ret)
                goto out_free_asid;
-       }
 
        cfg->cd.asid    = (u16)asid;
        cfg->cd.ttbr    = pgtbl_cfg->arm_lpae_s1_cfg.ttbr;