diff options
Diffstat (limited to 'drivers/iommu/sprd-iommu.c')
| -rw-r--r-- | drivers/iommu/sprd-iommu.c | 567 |
1 files changed, 567 insertions, 0 deletions
diff --git a/drivers/iommu/sprd-iommu.c b/drivers/iommu/sprd-iommu.c new file mode 100644 index 0000000000..2fa9afebd4 --- /dev/null +++ b/drivers/iommu/sprd-iommu.c @@ -0,0 +1,567 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Unisoc IOMMU driver + * + * Copyright (C) 2020 Unisoc, Inc. + * Author: Chunyan Zhang <chunyan.zhang@unisoc.com> + */ + +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/errno.h> +#include <linux/iommu.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define SPRD_IOMMU_PAGE_SHIFT 12 +#define SPRD_IOMMU_PAGE_SIZE SZ_4K + +#define SPRD_EX_CFG 0x0 +#define SPRD_IOMMU_VAOR_BYPASS BIT(4) +#define SPRD_IOMMU_GATE_EN BIT(1) +#define SPRD_IOMMU_EN BIT(0) +#define SPRD_EX_UPDATE 0x4 +#define SPRD_EX_FIRST_VPN 0x8 +#define SPRD_EX_VPN_RANGE 0xc +#define SPRD_EX_FIRST_PPN 0x10 +#define SPRD_EX_DEFAULT_PPN 0x14 + +#define SPRD_IOMMU_VERSION 0x0 +#define SPRD_VERSION_MASK GENMASK(15, 8) +#define SPRD_VERSION_SHIFT 0x8 +#define SPRD_VAU_CFG 0x4 +#define SPRD_VAU_UPDATE 0x8 +#define SPRD_VAU_AUTH_CFG 0xc +#define SPRD_VAU_FIRST_PPN 0x10 +#define SPRD_VAU_DEFAULT_PPN_RD 0x14 +#define SPRD_VAU_DEFAULT_PPN_WR 0x18 +#define SPRD_VAU_FIRST_VPN 0x1c +#define SPRD_VAU_VPN_RANGE 0x20 + +enum sprd_iommu_version { + SPRD_IOMMU_EX, + SPRD_IOMMU_VAU, +}; + +/* + * struct sprd_iommu_device - high-level sprd IOMMU device representation, + * including hardware information and configuration, also driver data, etc + * + * @ver: sprd IOMMU IP version + * @prot_page_va: protect page base virtual address + * @prot_page_pa: protect page base physical address, data would be + * written to here while translation fault + * @base: mapped base address for accessing registers + * @dev: pointer to basic device structure + * @iommu: IOMMU core representation + * @group: IOMMU group + * @eb: gate clock which controls IOMMU access + */ +struct sprd_iommu_device { + struct sprd_iommu_domain *dom; + enum sprd_iommu_version ver; + u32 *prot_page_va; + dma_addr_t prot_page_pa; + void __iomem *base; + struct device *dev; + struct iommu_device iommu; + struct iommu_group *group; + struct clk *eb; +}; + +struct sprd_iommu_domain { + spinlock_t pgtlock; /* lock for page table */ + struct iommu_domain domain; + u32 *pgt_va; /* page table virtual address base */ + dma_addr_t pgt_pa; /* page table physical address base */ + struct sprd_iommu_device *sdev; +}; + +static const struct iommu_ops sprd_iommu_ops; + +static struct sprd_iommu_domain *to_sprd_domain(struct iommu_domain *dom) +{ + return container_of(dom, struct sprd_iommu_domain, domain); +} + +static inline void +sprd_iommu_write(struct sprd_iommu_device *sdev, unsigned int reg, u32 val) +{ + writel_relaxed(val, sdev->base + reg); +} + +static inline u32 +sprd_iommu_read(struct sprd_iommu_device *sdev, unsigned int reg) +{ + return readl_relaxed(sdev->base + reg); +} + +static inline void +sprd_iommu_update_bits(struct sprd_iommu_device *sdev, unsigned int reg, + u32 mask, u32 shift, u32 val) +{ + u32 t = sprd_iommu_read(sdev, reg); + + t = (t & (~(mask << shift))) | ((val & mask) << shift); + sprd_iommu_write(sdev, reg, t); +} + +static inline int +sprd_iommu_get_version(struct sprd_iommu_device *sdev) +{ + int ver = (sprd_iommu_read(sdev, SPRD_IOMMU_VERSION) & + SPRD_VERSION_MASK) >> SPRD_VERSION_SHIFT; + + switch (ver) { + case SPRD_IOMMU_EX: + case SPRD_IOMMU_VAU: + return ver; + default: + return -EINVAL; + } +} + +static size_t +sprd_iommu_pgt_size(struct iommu_domain *domain) +{ + return ((domain->geometry.aperture_end - + domain->geometry.aperture_start + 1) >> + SPRD_IOMMU_PAGE_SHIFT) * sizeof(u32); +} + +static struct iommu_domain *sprd_iommu_domain_alloc(unsigned int domain_type) +{ + struct sprd_iommu_domain *dom; + + if (domain_type != IOMMU_DOMAIN_DMA && domain_type != IOMMU_DOMAIN_UNMANAGED) + return NULL; + + dom = kzalloc(sizeof(*dom), GFP_KERNEL); + if (!dom) + return NULL; + + spin_lock_init(&dom->pgtlock); + + dom->domain.geometry.aperture_start = 0; + dom->domain.geometry.aperture_end = SZ_256M - 1; + dom->domain.geometry.force_aperture = true; + + return &dom->domain; +} + +static void sprd_iommu_first_vpn(struct sprd_iommu_domain *dom) +{ + struct sprd_iommu_device *sdev = dom->sdev; + u32 val; + unsigned int reg; + + if (sdev->ver == SPRD_IOMMU_EX) + reg = SPRD_EX_FIRST_VPN; + else + reg = SPRD_VAU_FIRST_VPN; + + val = dom->domain.geometry.aperture_start >> SPRD_IOMMU_PAGE_SHIFT; + sprd_iommu_write(sdev, reg, val); +} + +static void sprd_iommu_vpn_range(struct sprd_iommu_domain *dom) +{ + struct sprd_iommu_device *sdev = dom->sdev; + u32 val; + unsigned int reg; + + if (sdev->ver == SPRD_IOMMU_EX) + reg = SPRD_EX_VPN_RANGE; + else + reg = SPRD_VAU_VPN_RANGE; + + val = (dom->domain.geometry.aperture_end - + dom->domain.geometry.aperture_start) >> SPRD_IOMMU_PAGE_SHIFT; + sprd_iommu_write(sdev, reg, val); +} + +static void sprd_iommu_first_ppn(struct sprd_iommu_domain *dom) +{ + u32 val = dom->pgt_pa >> SPRD_IOMMU_PAGE_SHIFT; + struct sprd_iommu_device *sdev = dom->sdev; + unsigned int reg; + + if (sdev->ver == SPRD_IOMMU_EX) + reg = SPRD_EX_FIRST_PPN; + else + reg = SPRD_VAU_FIRST_PPN; + + sprd_iommu_write(sdev, reg, val); +} + +static void sprd_iommu_default_ppn(struct sprd_iommu_device *sdev) +{ + u32 val = sdev->prot_page_pa >> SPRD_IOMMU_PAGE_SHIFT; + + if (sdev->ver == SPRD_IOMMU_EX) { + sprd_iommu_write(sdev, SPRD_EX_DEFAULT_PPN, val); + } else if (sdev->ver == SPRD_IOMMU_VAU) { + sprd_iommu_write(sdev, SPRD_VAU_DEFAULT_PPN_RD, val); + sprd_iommu_write(sdev, SPRD_VAU_DEFAULT_PPN_WR, val); + } +} + +static void sprd_iommu_hw_en(struct sprd_iommu_device *sdev, bool en) +{ + unsigned int reg_cfg; + u32 mask, val; + + if (sdev->ver == SPRD_IOMMU_EX) + reg_cfg = SPRD_EX_CFG; + else + reg_cfg = SPRD_VAU_CFG; + + mask = SPRD_IOMMU_EN | SPRD_IOMMU_GATE_EN; + val = en ? mask : 0; + sprd_iommu_update_bits(sdev, reg_cfg, mask, 0, val); +} + +static void sprd_iommu_cleanup(struct sprd_iommu_domain *dom) +{ + size_t pgt_size; + + /* Nothing need to do if the domain hasn't been attached */ + if (!dom->sdev) + return; + + pgt_size = sprd_iommu_pgt_size(&dom->domain); + dma_free_coherent(dom->sdev->dev, pgt_size, dom->pgt_va, dom->pgt_pa); + dom->sdev = NULL; + sprd_iommu_hw_en(dom->sdev, false); +} + +static void sprd_iommu_domain_free(struct iommu_domain *domain) +{ + struct sprd_iommu_domain *dom = to_sprd_domain(domain); + + sprd_iommu_cleanup(dom); + kfree(dom); +} + +static int sprd_iommu_attach_device(struct iommu_domain *domain, + struct device *dev) +{ + struct sprd_iommu_device *sdev = dev_iommu_priv_get(dev); + struct sprd_iommu_domain *dom = to_sprd_domain(domain); + size_t pgt_size = sprd_iommu_pgt_size(domain); + + /* The device is attached to this domain */ + if (sdev->dom == dom) + return 0; + + /* The first time that domain is attaching to a device */ + if (!dom->pgt_va) { + dom->pgt_va = dma_alloc_coherent(sdev->dev, pgt_size, &dom->pgt_pa, GFP_KERNEL); + if (!dom->pgt_va) + return -ENOMEM; + + dom->sdev = sdev; + } + + sdev->dom = dom; + + /* + * One sprd IOMMU serves one client device only, disabled it before + * configure mapping table to avoid access conflict in case other + * mapping table is stored in. + */ + sprd_iommu_hw_en(sdev, false); + sprd_iommu_first_ppn(dom); + sprd_iommu_first_vpn(dom); + sprd_iommu_vpn_range(dom); + sprd_iommu_default_ppn(sdev); + sprd_iommu_hw_en(sdev, true); + + return 0; +} + +static int sprd_iommu_map(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t pgsize, size_t pgcount, + int prot, gfp_t gfp, size_t *mapped) +{ + struct sprd_iommu_domain *dom = to_sprd_domain(domain); + size_t size = pgcount * SPRD_IOMMU_PAGE_SIZE; + unsigned long flags; + unsigned int i; + u32 *pgt_base_iova; + u32 pabase = (u32)paddr; + unsigned long start = domain->geometry.aperture_start; + unsigned long end = domain->geometry.aperture_end; + + if (!dom->sdev) { + pr_err("No sprd_iommu_device attached to the domain\n"); + return -EINVAL; + } + + if (iova < start || (iova + size) > (end + 1)) { + dev_err(dom->sdev->dev, "(iova(0x%lx) + size(%zx)) are not in the range!\n", + iova, size); + return -EINVAL; + } + + pgt_base_iova = dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT); + + spin_lock_irqsave(&dom->pgtlock, flags); + for (i = 0; i < pgcount; i++) { + pgt_base_iova[i] = pabase >> SPRD_IOMMU_PAGE_SHIFT; + pabase += SPRD_IOMMU_PAGE_SIZE; + } + spin_unlock_irqrestore(&dom->pgtlock, flags); + + *mapped = size; + return 0; +} + +static size_t sprd_iommu_unmap(struct iommu_domain *domain, unsigned long iova, + size_t pgsize, size_t pgcount, + struct iommu_iotlb_gather *iotlb_gather) +{ + struct sprd_iommu_domain *dom = to_sprd_domain(domain); + unsigned long flags; + u32 *pgt_base_iova; + size_t size = pgcount * SPRD_IOMMU_PAGE_SIZE; + unsigned long start = domain->geometry.aperture_start; + unsigned long end = domain->geometry.aperture_end; + + if (iova < start || (iova + size) > (end + 1)) + return 0; + + pgt_base_iova = dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT); + + spin_lock_irqsave(&dom->pgtlock, flags); + memset(pgt_base_iova, 0, pgcount * sizeof(u32)); + spin_unlock_irqrestore(&dom->pgtlock, flags); + + return size; +} + +static void sprd_iommu_sync_map(struct iommu_domain *domain, + unsigned long iova, size_t size) +{ + struct sprd_iommu_domain *dom = to_sprd_domain(domain); + unsigned int reg; + + if (dom->sdev->ver == SPRD_IOMMU_EX) + reg = SPRD_EX_UPDATE; + else + reg = SPRD_VAU_UPDATE; + + /* clear IOMMU TLB buffer after page table updated */ + sprd_iommu_write(dom->sdev, reg, 0xffffffff); +} + +static void sprd_iommu_sync(struct iommu_domain *domain, + struct iommu_iotlb_gather *iotlb_gather) +{ + sprd_iommu_sync_map(domain, 0, 0); +} + +static phys_addr_t sprd_iommu_iova_to_phys(struct iommu_domain *domain, + dma_addr_t iova) +{ + struct sprd_iommu_domain *dom = to_sprd_domain(domain); + unsigned long flags; + phys_addr_t pa; + unsigned long start = domain->geometry.aperture_start; + unsigned long end = domain->geometry.aperture_end; + + if (WARN_ON(iova < start || iova > end)) + return 0; + + spin_lock_irqsave(&dom->pgtlock, flags); + pa = *(dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT)); + pa = (pa << SPRD_IOMMU_PAGE_SHIFT) + ((iova - start) & (SPRD_IOMMU_PAGE_SIZE - 1)); + spin_unlock_irqrestore(&dom->pgtlock, flags); + + return pa; +} + +static struct iommu_device *sprd_iommu_probe_device(struct device *dev) +{ + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + struct sprd_iommu_device *sdev; + + if (!fwspec || fwspec->ops != &sprd_iommu_ops) + return ERR_PTR(-ENODEV); + + sdev = dev_iommu_priv_get(dev); + + return &sdev->iommu; +} + +static struct iommu_group *sprd_iommu_device_group(struct device *dev) +{ + struct sprd_iommu_device *sdev = dev_iommu_priv_get(dev); + + return iommu_group_ref_get(sdev->group); +} + +static int sprd_iommu_of_xlate(struct device *dev, struct of_phandle_args *args) +{ + struct platform_device *pdev; + + if (!dev_iommu_priv_get(dev)) { + pdev = of_find_device_by_node(args->np); + dev_iommu_priv_set(dev, platform_get_drvdata(pdev)); + platform_device_put(pdev); + } + + return 0; +} + + +static const struct iommu_ops sprd_iommu_ops = { + .domain_alloc = sprd_iommu_domain_alloc, + .probe_device = sprd_iommu_probe_device, + .device_group = sprd_iommu_device_group, + .of_xlate = sprd_iommu_of_xlate, + .pgsize_bitmap = SPRD_IOMMU_PAGE_SIZE, + .owner = THIS_MODULE, + .default_domain_ops = &(const struct iommu_domain_ops) { + .attach_dev = sprd_iommu_attach_device, + .map_pages = sprd_iommu_map, + .unmap_pages = sprd_iommu_unmap, + .iotlb_sync_map = sprd_iommu_sync_map, + .iotlb_sync = sprd_iommu_sync, + .iova_to_phys = sprd_iommu_iova_to_phys, + .free = sprd_iommu_domain_free, + } +}; + +static const struct of_device_id sprd_iommu_of_match[] = { + { .compatible = "sprd,iommu-v1" }, + { }, +}; +MODULE_DEVICE_TABLE(of, sprd_iommu_of_match); + +/* + * Clock is not required, access to some of IOMMUs is controlled by gate + * clk, enabled clocks for that kind of IOMMUs before accessing. + * Return 0 for success or no clocks found. + */ +static int sprd_iommu_clk_enable(struct sprd_iommu_device *sdev) +{ + struct clk *eb; + + eb = devm_clk_get_optional(sdev->dev, NULL); + if (!eb) + return 0; + + if (IS_ERR(eb)) + return PTR_ERR(eb); + + sdev->eb = eb; + return clk_prepare_enable(eb); +} + +static void sprd_iommu_clk_disable(struct sprd_iommu_device *sdev) +{ + if (sdev->eb) + clk_disable_unprepare(sdev->eb); +} + +static int sprd_iommu_probe(struct platform_device *pdev) +{ + struct sprd_iommu_device *sdev; + struct device *dev = &pdev->dev; + void __iomem *base; + int ret; + + sdev = devm_kzalloc(dev, sizeof(*sdev), GFP_KERNEL); + if (!sdev) + return -ENOMEM; + + base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) { + dev_err(dev, "Failed to get ioremap resource.\n"); + return PTR_ERR(base); + } + sdev->base = base; + + sdev->prot_page_va = dma_alloc_coherent(dev, SPRD_IOMMU_PAGE_SIZE, + &sdev->prot_page_pa, GFP_KERNEL); + if (!sdev->prot_page_va) + return -ENOMEM; + + platform_set_drvdata(pdev, sdev); + sdev->dev = dev; + + /* All the client devices are in the same iommu-group */ + sdev->group = iommu_group_alloc(); + if (IS_ERR(sdev->group)) { + ret = PTR_ERR(sdev->group); + goto free_page; + } + + ret = iommu_device_sysfs_add(&sdev->iommu, dev, NULL, dev_name(dev)); + if (ret) + goto put_group; + + ret = iommu_device_register(&sdev->iommu, &sprd_iommu_ops, dev); + if (ret) + goto remove_sysfs; + + ret = sprd_iommu_clk_enable(sdev); + if (ret) + goto unregister_iommu; + + ret = sprd_iommu_get_version(sdev); + if (ret < 0) { + dev_err(dev, "IOMMU version(%d) is invalid.\n", ret); + goto disable_clk; + } + sdev->ver = ret; + + return 0; + +disable_clk: + sprd_iommu_clk_disable(sdev); +unregister_iommu: + iommu_device_unregister(&sdev->iommu); +remove_sysfs: + iommu_device_sysfs_remove(&sdev->iommu); +put_group: + iommu_group_put(sdev->group); +free_page: + dma_free_coherent(sdev->dev, SPRD_IOMMU_PAGE_SIZE, sdev->prot_page_va, sdev->prot_page_pa); + return ret; +} + +static void sprd_iommu_remove(struct platform_device *pdev) +{ + struct sprd_iommu_device *sdev = platform_get_drvdata(pdev); + + dma_free_coherent(sdev->dev, SPRD_IOMMU_PAGE_SIZE, sdev->prot_page_va, sdev->prot_page_pa); + + iommu_group_put(sdev->group); + sdev->group = NULL; + + platform_set_drvdata(pdev, NULL); + iommu_device_sysfs_remove(&sdev->iommu); + iommu_device_unregister(&sdev->iommu); +} + +static struct platform_driver sprd_iommu_driver = { + .driver = { + .name = "sprd-iommu", + .of_match_table = sprd_iommu_of_match, + .suppress_bind_attrs = true, + }, + .probe = sprd_iommu_probe, + .remove_new = sprd_iommu_remove, +}; +module_platform_driver(sprd_iommu_driver); + +MODULE_DESCRIPTION("IOMMU driver for Unisoc SoCs"); +MODULE_ALIAS("platform:sprd-iommu"); +MODULE_LICENSE("GPL"); |