From: Krishna Reddy Date: Sat, 18 Jul 2020 19:34:55 +0000 (-0700) Subject: iommu/arm-smmu: add NVIDIA implementation for ARM MMU-500 usage X-Git-Tag: v5.15~3124^2^2~3 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=aab5a1c882760a5bc990b14e5c0c2ee4dab5f1ac;p=platform%2Fkernel%2Flinux-starfive.git iommu/arm-smmu: add NVIDIA implementation for ARM MMU-500 usage NVIDIA's Tegra194 SoC has three ARM MMU-500 instances. It uses two of the ARM MMU-500s together to interleave IOVA accesses across them and must be programmed identically. This implementation supports programming the two ARM MMU-500s that must be programmed identically. The third ARM MMU-500 instance is supported by standard arm-smmu.c driver itself. Signed-off-by: Krishna Reddy Reviewed-by: Jon Hunter Reviewed-by: Nicolin Chen Reviewed-by: Pritesh Raithatha Reviewed-by: Robin Murphy Reviewed-by: Thierry Reding Link: https://lore.kernel.org/r/20200718193457.30046-4-vdumpa@nvidia.com Signed-off-by: Will Deacon --- diff --git a/MAINTAINERS b/MAINTAINERS index 496fd4ea..ee2c0ba 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -16810,8 +16810,10 @@ F: drivers/i2c/busses/i2c-tegra.c TEGRA IOMMU DRIVERS M: Thierry Reding +R: Krishna Reddy L: linux-tegra@vger.kernel.org S: Supported +F: drivers/iommu/arm-smmu-nvidia.c F: drivers/iommu/tegra* TEGRA KBC DRIVER diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile index 3421901..2b8203d 100644 --- a/drivers/iommu/Makefile +++ b/drivers/iommu/Makefile @@ -15,7 +15,7 @@ obj-$(CONFIG_AMD_IOMMU) += amd/iommu.o amd/init.o amd/quirks.o obj-$(CONFIG_AMD_IOMMU_DEBUGFS) += amd/debugfs.o obj-$(CONFIG_AMD_IOMMU_V2) += amd/iommu_v2.o obj-$(CONFIG_ARM_SMMU) += arm_smmu.o -arm_smmu-objs += arm-smmu.o arm-smmu-impl.o arm-smmu-qcom.o +arm_smmu-objs += arm-smmu.o arm-smmu-impl.o arm-smmu-nvidia.o arm-smmu-qcom.o obj-$(CONFIG_ARM_SMMU_V3) += arm-smmu-v3.o obj-$(CONFIG_DMAR_TABLE) += intel/dmar.o obj-$(CONFIG_INTEL_IOMMU) += intel/iommu.o intel/pasid.o diff --git a/drivers/iommu/arm-smmu-impl.c b/drivers/iommu/arm-smmu-impl.c index c87d825..f4ff124 100644 --- a/drivers/iommu/arm-smmu-impl.c +++ b/drivers/iommu/arm-smmu-impl.c @@ -213,6 +213,9 @@ struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu) if (of_property_read_bool(np, "calxeda,smmu-secure-config-access")) smmu->impl = &calxeda_impl; + if (of_device_is_compatible(np, "nvidia,tegra194-smmu")) + return nvidia_smmu_impl_init(smmu); + if (of_device_is_compatible(np, "qcom,sdm845-smmu-500") || of_device_is_compatible(np, "qcom,sc7180-smmu-500") || of_device_is_compatible(np, "qcom,sm8150-smmu-500") || diff --git a/drivers/iommu/arm-smmu-nvidia.c b/drivers/iommu/arm-smmu-nvidia.c new file mode 100644 index 0000000..2f55e57 --- /dev/null +++ b/drivers/iommu/arm-smmu-nvidia.c @@ -0,0 +1,179 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2019-2020 NVIDIA CORPORATION. All rights reserved. + +#include +#include +#include +#include +#include + +#include "arm-smmu.h" + +/* + * Tegra194 has three ARM MMU-500 Instances. + * Two of them are used together and must be programmed identically for + * interleaved IOVA accesses across them and translates accesses from + * non-isochronous HW devices. + * Third one is used for translating accesses from isochronous HW devices. + * This implementation supports programming of the two instances that must + * be programmed identically. + * The third instance usage is through standard arm-smmu driver itself and + * is out of scope of this implementation. + */ +#define NUM_SMMU_INSTANCES 2 + +struct nvidia_smmu { + struct arm_smmu_device smmu; + void __iomem *bases[NUM_SMMU_INSTANCES]; +}; + +static inline void __iomem *nvidia_smmu_page(struct arm_smmu_device *smmu, + unsigned int inst, int page) +{ + struct nvidia_smmu *nvidia_smmu; + + nvidia_smmu = container_of(smmu, struct nvidia_smmu, smmu); + return nvidia_smmu->bases[inst] + (page << smmu->pgshift); +} + +static u32 nvidia_smmu_read_reg(struct arm_smmu_device *smmu, + int page, int offset) +{ + void __iomem *reg = nvidia_smmu_page(smmu, 0, page) + offset; + + return readl_relaxed(reg); +} + +static void nvidia_smmu_write_reg(struct arm_smmu_device *smmu, + int page, int offset, u32 val) +{ + unsigned int i; + + for (i = 0; i < NUM_SMMU_INSTANCES; i++) { + void __iomem *reg = nvidia_smmu_page(smmu, i, page) + offset; + + writel_relaxed(val, reg); + } +} + +static u64 nvidia_smmu_read_reg64(struct arm_smmu_device *smmu, + int page, int offset) +{ + void __iomem *reg = nvidia_smmu_page(smmu, 0, page) + offset; + + return readq_relaxed(reg); +} + +static void nvidia_smmu_write_reg64(struct arm_smmu_device *smmu, + int page, int offset, u64 val) +{ + unsigned int i; + + for (i = 0; i < NUM_SMMU_INSTANCES; i++) { + void __iomem *reg = nvidia_smmu_page(smmu, i, page) + offset; + + writeq_relaxed(val, reg); + } +} + +static void nvidia_smmu_tlb_sync(struct arm_smmu_device *smmu, int page, + int sync, int status) +{ + unsigned int delay; + + arm_smmu_writel(smmu, page, sync, 0); + + for (delay = 1; delay < TLB_LOOP_TIMEOUT; delay *= 2) { + unsigned int spin_cnt; + + for (spin_cnt = TLB_SPIN_COUNT; spin_cnt > 0; spin_cnt--) { + u32 val = 0; + unsigned int i; + + for (i = 0; i < NUM_SMMU_INSTANCES; i++) { + void __iomem *reg; + + reg = nvidia_smmu_page(smmu, i, page) + status; + val |= readl_relaxed(reg); + } + + if (!(val & ARM_SMMU_sTLBGSTATUS_GSACTIVE)) + return; + + cpu_relax(); + } + + udelay(delay); + } + + dev_err_ratelimited(smmu->dev, + "TLB sync timed out -- SMMU may be deadlocked\n"); +} + +static int nvidia_smmu_reset(struct arm_smmu_device *smmu) +{ + unsigned int i; + + for (i = 0; i < NUM_SMMU_INSTANCES; i++) { + u32 val; + void __iomem *reg = nvidia_smmu_page(smmu, i, ARM_SMMU_GR0) + + ARM_SMMU_GR0_sGFSR; + + /* clear global FSR */ + val = readl_relaxed(reg); + writel_relaxed(val, reg); + } + + return 0; +} + +static const struct arm_smmu_impl nvidia_smmu_impl = { + .read_reg = nvidia_smmu_read_reg, + .write_reg = nvidia_smmu_write_reg, + .read_reg64 = nvidia_smmu_read_reg64, + .write_reg64 = nvidia_smmu_write_reg64, + .reset = nvidia_smmu_reset, + .tlb_sync = nvidia_smmu_tlb_sync, +}; + +struct arm_smmu_device *nvidia_smmu_impl_init(struct arm_smmu_device *smmu) +{ + struct resource *res; + struct device *dev = smmu->dev; + struct nvidia_smmu *nvidia_smmu; + struct platform_device *pdev = to_platform_device(dev); + + nvidia_smmu = devm_kzalloc(dev, sizeof(*nvidia_smmu), GFP_KERNEL); + if (!nvidia_smmu) + return ERR_PTR(-ENOMEM); + + /* + * Copy the data from struct arm_smmu_device *smmu allocated in + * arm-smmu.c. The smmu from struct nvidia_smmu replaces the smmu + * pointer used in arm-smmu.c once this function returns. + * This is necessary to derive nvidia_smmu from smmu pointer passed + * through arm_smmu_impl function calls subsequently. + */ + nvidia_smmu->smmu = *smmu; + /* Instance 0 is ioremapped by arm-smmu.c. */ + nvidia_smmu->bases[0] = smmu->base; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!res) + return ERR_PTR(-ENODEV); + + nvidia_smmu->bases[1] = devm_ioremap_resource(dev, res); + if (IS_ERR(nvidia_smmu->bases[1])) + return ERR_CAST(nvidia_smmu->bases[1]); + + nvidia_smmu->smmu.impl = &nvidia_smmu_impl; + + /* + * Free the struct arm_smmu_device *smmu allocated in arm-smmu.c. + * Once this function returns, arm-smmu.c would use arm_smmu_device + * allocated as part of struct nvidia_smmu. + */ + devm_kfree(dev, smmu); + + return &nvidia_smmu->smmu; +} diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index de52011..35422a1 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1946,6 +1946,7 @@ static const struct of_device_id arm_smmu_of_match[] = { { .compatible = "arm,mmu-401", .data = &arm_mmu401 }, { .compatible = "arm,mmu-500", .data = &arm_mmu500 }, { .compatible = "cavium,smmu-v2", .data = &cavium_smmuv2 }, + { .compatible = "nvidia,smmu-500", .data = &arm_mmu500 }, { .compatible = "qcom,smmu-v2", .data = &qcom_smmuv2 }, { }, }; diff --git a/drivers/iommu/arm-smmu.h b/drivers/iommu/arm-smmu.h index c7d0122..fad63ef 100644 --- a/drivers/iommu/arm-smmu.h +++ b/drivers/iommu/arm-smmu.h @@ -452,6 +452,7 @@ static inline void arm_smmu_writeq(struct arm_smmu_device *smmu, int page, arm_smmu_writeq((s), ARM_SMMU_CB((s), (n)), (o), (v)) struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu); +struct arm_smmu_device *nvidia_smmu_impl_init(struct arm_smmu_device *smmu); struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu); int arm_mmu500_reset(struct arm_smmu_device *smmu);