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Diffstat (limited to 'drivers/iommu/arm-smmu-impl.c')
-rw-r--r--drivers/iommu/arm-smmu-impl.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/drivers/iommu/arm-smmu-impl.c b/drivers/iommu/arm-smmu-impl.c
new file mode 100644
index 000000000000..5c87a38620c4
--- /dev/null
+++ b/drivers/iommu/arm-smmu-impl.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Miscellaneous Arm SMMU implementation and integration quirks
+// Copyright (C) 2019 Arm Limited
+
+#define pr_fmt(fmt) "arm-smmu: " fmt
+
+#include <linux/bitfield.h>
+#include <linux/of.h>
+
+#include "arm-smmu.h"
+
+
+static int arm_smmu_gr0_ns(int offset)
+{
+ switch(offset) {
+ case ARM_SMMU_GR0_sCR0:
+ case ARM_SMMU_GR0_sACR:
+ case ARM_SMMU_GR0_sGFSR:
+ case ARM_SMMU_GR0_sGFSYNR0:
+ case ARM_SMMU_GR0_sGFSYNR1:
+ case ARM_SMMU_GR0_sGFSYNR2:
+ return offset + 0x400;
+ default:
+ return offset;
+ }
+}
+
+static u32 arm_smmu_read_ns(struct arm_smmu_device *smmu, int page,
+ int offset)
+{
+ if (page == ARM_SMMU_GR0)
+ offset = arm_smmu_gr0_ns(offset);
+ return readl_relaxed(arm_smmu_page(smmu, page) + offset);
+}
+
+static void arm_smmu_write_ns(struct arm_smmu_device *smmu, int page,
+ int offset, u32 val)
+{
+ if (page == ARM_SMMU_GR0)
+ offset = arm_smmu_gr0_ns(offset);
+ writel_relaxed(val, arm_smmu_page(smmu, page) + offset);
+}
+
+/* Since we don't care for sGFAR, we can do without 64-bit accessors */
+static const struct arm_smmu_impl calxeda_impl = {
+ .read_reg = arm_smmu_read_ns,
+ .write_reg = arm_smmu_write_ns,
+};
+
+
+struct cavium_smmu {
+ struct arm_smmu_device smmu;
+ u32 id_base;
+};
+
+static int cavium_cfg_probe(struct arm_smmu_device *smmu)
+{
+ static atomic_t context_count = ATOMIC_INIT(0);
+ struct cavium_smmu *cs = container_of(smmu, struct cavium_smmu, smmu);
+ /*
+ * Cavium CN88xx erratum #27704.
+ * Ensure ASID and VMID allocation is unique across all SMMUs in
+ * the system.
+ */
+ cs->id_base = atomic_fetch_add(smmu->num_context_banks, &context_count);
+ dev_notice(smmu->dev, "\tenabling workaround for Cavium erratum 27704\n");
+
+ return 0;
+}
+
+static int cavium_init_context(struct arm_smmu_domain *smmu_domain)
+{
+ struct cavium_smmu *cs = container_of(smmu_domain->smmu,
+ struct cavium_smmu, smmu);
+
+ if (smmu_domain->stage == ARM_SMMU_DOMAIN_S2)
+ smmu_domain->cfg.vmid += cs->id_base;
+ else
+ smmu_domain->cfg.asid += cs->id_base;
+
+ return 0;
+}
+
+static const struct arm_smmu_impl cavium_impl = {
+ .cfg_probe = cavium_cfg_probe,
+ .init_context = cavium_init_context,
+};
+
+static struct arm_smmu_device *cavium_smmu_impl_init(struct arm_smmu_device *smmu)
+{
+ struct cavium_smmu *cs;
+
+ cs = devm_kzalloc(smmu->dev, sizeof(*cs), GFP_KERNEL);
+ if (!cs)
+ return ERR_PTR(-ENOMEM);
+
+ cs->smmu = *smmu;
+ cs->smmu.impl = &cavium_impl;
+
+ devm_kfree(smmu->dev, smmu);
+
+ return &cs->smmu;
+}
+
+
+#define ARM_MMU500_ACTLR_CPRE (1 << 1)
+
+#define ARM_MMU500_ACR_CACHE_LOCK (1 << 26)
+#define ARM_MMU500_ACR_S2CRB_TLBEN (1 << 10)
+#define ARM_MMU500_ACR_SMTNMB_TLBEN (1 << 8)
+
+static int arm_mmu500_reset(struct arm_smmu_device *smmu)
+{
+ u32 reg, major;
+ int i;
+ /*
+ * On MMU-500 r2p0 onwards we need to clear ACR.CACHE_LOCK before
+ * writes to the context bank ACTLRs will stick. And we just hope that
+ * Secure has also cleared SACR.CACHE_LOCK for this to take effect...
+ */
+ reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_ID7);
+ major = FIELD_GET(ID7_MAJOR, reg);
+ reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sACR);
+ if (major >= 2)
+ reg &= ~ARM_MMU500_ACR_CACHE_LOCK;
+ /*
+ * Allow unmatched Stream IDs to allocate bypass
+ * TLB entries for reduced latency.
+ */
+ reg |= ARM_MMU500_ACR_SMTNMB_TLBEN | ARM_MMU500_ACR_S2CRB_TLBEN;
+ arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sACR, reg);
+
+ /*
+ * Disable MMU-500's not-particularly-beneficial next-page
+ * prefetcher for the sake of errata #841119 and #826419.
+ */
+ for (i = 0; i < smmu->num_context_banks; ++i) {
+ reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR);
+ reg &= ~ARM_MMU500_ACTLR_CPRE;
+ arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg);
+ }
+
+ return 0;
+}
+
+static const struct arm_smmu_impl arm_mmu500_impl = {
+ .reset = arm_mmu500_reset,
+};
+
+
+struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu)
+{
+ /*
+ * We will inevitably have to combine model-specific implementation
+ * quirks with platform-specific integration quirks, but everything
+ * we currently support happens to work out as straightforward
+ * mutually-exclusive assignments.
+ */
+ switch (smmu->model) {
+ case ARM_MMU500:
+ smmu->impl = &arm_mmu500_impl;
+ break;
+ case CAVIUM_SMMUV2:
+ return cavium_smmu_impl_init(smmu);
+ default:
+ break;
+ }
+
+ if (of_property_read_bool(smmu->dev->of_node,
+ "calxeda,smmu-secure-config-access"))
+ smmu->impl = &calxeda_impl;
+
+ return smmu;
+}