// 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 io_pgtable_cfg *pgtbl_cfg, struct device *dev)
{
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_krealloc(smmu->dev, smmu, sizeof(*cs), GFP_KERNEL);
if (!cs)
return ERR_PTR(-ENOMEM);
cs->smmu.impl = &cavium_impl;
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)
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(ARM_SMMU_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);
reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR);
if (reg & ARM_MMU500_ACTLR_CPRE)
dev_warn_once(smmu->dev, "Failed to disable prefetcher [errata #841119 and #826419], check ACR.CACHE_LOCK\n");
}
return 0;
}
static const struct arm_smmu_impl arm_mmu500_impl = {
.reset = arm_mmu500_reset,
};
static u64 mrvl_mmu500_readq(struct arm_smmu_device *smmu, int page, int off)
{
/*
* Marvell Armada-AP806 erratum #582743.
* Split all the readq to double readl
*/
return hi_lo_readq_relaxed(arm_smmu_page(smmu, page) + off);
}
static void mrvl_mmu500_writeq(struct arm_smmu_device *smmu, int page, int off,
u64 val)
{
/*
* Marvell Armada-AP806 erratum #582743.
* Split all the writeq to double writel
*/
hi_lo_writeq_relaxed(val, arm_smmu_page(smmu, page) + off);
}
static int mrvl_mmu500_cfg_probe(struct arm_smmu_device *smmu)
{
/*
* Armada-AP806 erratum #582743.
* Hide the SMMU_IDR2.PTFSv8 fields to sidestep the AArch64
* formats altogether and allow using 32 bits access on the
* interconnect.
*/
smmu->features &= ~(ARM_SMMU_FEAT_FMT_AARCH64_4K |
ARM_SMMU_FEAT_FMT_AARCH64_16K |
ARM_SMMU_FEAT_FMT_AARCH64_64K);
return 0;
}
static const struct arm_smmu_impl mrvl_mmu500_impl = {
.read_reg64 = mrvl_mmu500_readq,
.write_reg64 = mrvl_mmu500_writeq,
.cfg_probe = mrvl_mmu500_cfg_probe,
.reset = arm_mmu500_reset,
};
struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu)
{
const struct device_node *np = smmu->dev->of_node;
/*
* Set the impl for model-specific implementation quirks first,
* such that platform integration quirks can pick it up and
* inherit from it if necessary.
*/
switch (smmu->model) {
case ARM_MMU500:
smmu->impl = &arm_mmu500_impl;
break;
case CAVIUM_SMMUV2:
return cavium_smmu_impl_init(smmu);
default:
break;
}
/* This is implicitly MMU-400 */
if (of_property_read_bool(np, "calxeda,smmu-secure-config-access"))
smmu->impl = &calxeda_impl;
if (of_device_is_compatible(np, "nvidia,tegra234-smmu") ||
of_device_is_compatible(np, "nvidia,tegra194-smmu") ||
of_device_is_compatible(np, "nvidia,tegra186-smmu"))
return nvidia_smmu_impl_init(smmu);
if (IS_ENABLED(CONFIG_ARM_SMMU_QCOM))
smmu = qcom_smmu_impl_init(smmu);
if (of_device_is_compatible(np, "marvell,ap806-smmu-500"))
smmu->impl = &mrvl_mmu500_impl;
return smmu;
}
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