[PATCH v3 3/5] iommu: Add Allwinner H6 IOMMU driver
Maxime Ripard
maxime at cerno.tech
Tue May 5 10:09:32 UTC 2020
The Allwinner H6 has introduced an IOMMU for a few DMA controllers, mostly
video related: the display engine, the video decoders / encoders, the
camera capture controller, etc.
The design is pretty simple compared to other IOMMUs found in SoCs: there's
a single instance, controlling all the masters, with a single address
space.
It also features a performance monitoring unit that allows to retrieve
various informations (per-master and global TLB accesses, hits and misses,
access latency, etc) that isn't supported at the moment.
Signed-off-by: Maxime Ripard <maxime at cerno.tech>
---
drivers/iommu/Kconfig | 9 +-
drivers/iommu/Makefile | 1 +-
drivers/iommu/sun50i-iommu.c | 1065 +++++++++++++++++++++++++++++++++++-
3 files changed, 1075 insertions(+)
create mode 100644 drivers/iommu/sun50i-iommu.c
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 58b4a4dbfc78..6e80b0ea7228 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -303,6 +303,15 @@ config ROCKCHIP_IOMMU
Say Y here if you are using a Rockchip SoC that includes an IOMMU
device.
+config SUN50I_IOMMU
+ bool "Allwinner H6 IOMMU Support"
+ depends on ARCH_SUNXI || COMPILE_TEST
+ select ARM_DMA_USE_IOMMU
+ select IOMMU_API
+ select IOMMU_DMA
+ help
+ Support for the IOMMU introduced in the Allwinner H6 SoCs.
+
config TEGRA_IOMMU_GART
bool "Tegra GART IOMMU Support"
depends on ARCH_TEGRA_2x_SOC
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 9f33fdb3bb05..57cf4ba5e27c 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_MTK_IOMMU_V1) += mtk_iommu_v1.o
obj-$(CONFIG_OMAP_IOMMU) += omap-iommu.o
obj-$(CONFIG_OMAP_IOMMU_DEBUG) += omap-iommu-debug.o
obj-$(CONFIG_ROCKCHIP_IOMMU) += rockchip-iommu.o
+obj-$(CONFIG_SUN50I_IOMMU) += sun50i-iommu.o
obj-$(CONFIG_TEGRA_IOMMU_GART) += tegra-gart.o
obj-$(CONFIG_TEGRA_IOMMU_SMMU) += tegra-smmu.o
obj-$(CONFIG_EXYNOS_IOMMU) += exynos-iommu.o
diff --git a/drivers/iommu/sun50i-iommu.c b/drivers/iommu/sun50i-iommu.c
new file mode 100644
index 000000000000..d4c3fa2f0f82
--- /dev/null
+++ b/drivers/iommu/sun50i-iommu.c
@@ -0,0 +1,1065 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+// Copyright (C) 2016-2018, Allwinner Technology CO., LTD.
+// Copyright (C) 2019-2020, Cerno
+
+#include <linux/bitfield.h>
+#include <linux/bug.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/iommu.h>
+#include <linux/iopoll.h>
+#include <linux/ioport.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#define IOMMU_RESET_REG 0x010
+#define IOMMU_ENABLE_REG 0x020
+#define IOMMU_ENABLE_ENABLE BIT(0)
+
+#define IOMMU_BYPASS_REG 0x030
+#define IOMMU_AUTO_GATING_REG 0x040
+#define IOMMU_AUTO_GATING_ENABLE BIT(0)
+
+#define IOMMU_WBUF_CTRL_REG 0x044
+#define IOMMU_OOO_CTRL_REG 0x048
+#define IOMMU_4KB_BDY_PRT_CTRL_REG 0x04c
+#define IOMMU_TTB_REG 0x050
+#define IOMMU_TLB_ENABLE_REG 0x060
+#define IOMMU_TLB_PREFETCH_REG 0x070
+#define IOMMU_TLB_PREFETCH_MASTER_ENABLE(m) BIT(m)
+
+#define IOMMU_TLB_FLUSH_REG 0x080
+#define IOMMU_TLB_FLUSH_PTW_CACHE BIT(17)
+#define IOMMU_TLB_FLUSH_MACRO_TLB BIT(16)
+#define IOMMU_TLB_FLUSH_MICRO_TLB(i) (BIT(i) & GENMASK(5, 0))
+
+#define IOMMU_TLB_IVLD_ADDR_REG 0x090
+#define IOMMU_TLB_IVLD_ADDR_MASK_REG 0x094
+#define IOMMU_TLB_IVLD_ENABLE_REG 0x098
+#define IOMMU_TLB_IVLD_ENABLE_ENABLE BIT(0)
+
+#define IOMMU_PC_IVLD_ADDR_REG 0x0a0
+#define IOMMU_PC_IVLD_ENABLE_REG 0x0a8
+#define IOMMU_PC_IVLD_ENABLE_ENABLE BIT(0)
+
+#define IOMMU_DM_AUT_CTRL_REG(d) (0x0b0 + ((d) / 2) * 4)
+#define IOMMU_DM_AUT_CTRL_RD_UNAVAIL(d, m) (1 << (((d & 1) * 16) + ((m) * 2)))
+#define IOMMU_DM_AUT_CTRL_WR_UNAVAIL(d, m) (1 << (((d & 1) * 16) + ((m) * 2) + 1))
+
+#define IOMMU_DM_AUT_OVWT_REG 0x0d0
+#define IOMMU_INT_ENABLE_REG 0x100
+#define IOMMU_INT_CLR_REG 0x104
+#define IOMMU_INT_STA_REG 0x108
+#define IOMMU_INT_ERR_ADDR_REG(i) (0x110 + (i) * 4)
+#define IOMMU_INT_ERR_ADDR_L1_REG 0x130
+#define IOMMU_INT_ERR_ADDR_L2_REG 0x134
+#define IOMMU_INT_ERR_DATA_REG(i) (0x150 + (i) * 4)
+#define IOMMU_L1PG_INT_REG 0x0180
+#define IOMMU_L2PG_INT_REG 0x0184
+
+#define IOMMU_INT_INVALID_L2PG BIT(17)
+#define IOMMU_INT_INVALID_L1PG BIT(16)
+#define IOMMU_INT_MASTER_PERMISSION(m) BIT(m)
+#define IOMMU_INT_MASTER_MASK (IOMMU_INT_MASTER_PERMISSION(0) | \
+ IOMMU_INT_MASTER_PERMISSION(1) | \
+ IOMMU_INT_MASTER_PERMISSION(2) | \
+ IOMMU_INT_MASTER_PERMISSION(3) | \
+ IOMMU_INT_MASTER_PERMISSION(4) | \
+ IOMMU_INT_MASTER_PERMISSION(5))
+#define IOMMU_INT_MASK (IOMMU_INT_INVALID_L1PG | \
+ IOMMU_INT_INVALID_L2PG | \
+ IOMMU_INT_MASTER_MASK)
+
+#define PT_ENTRY_SIZE sizeof(u32)
+
+#define NUM_DT_ENTRIES 4096
+#define DT_SIZE (NUM_DT_ENTRIES * PT_ENTRY_SIZE)
+
+#define NUM_PT_ENTRIES 256
+#define PT_SIZE (NUM_PT_ENTRIES * PT_ENTRY_SIZE)
+
+struct sun50i_iommu {
+ struct iommu_device iommu;
+
+ /* Lock to modify the IOMMU registers */
+ spinlock_t iommu_lock;
+
+ struct device *dev;
+ void __iomem *base;
+ struct reset_control *reset;
+ struct clk *clk;
+
+ struct iommu_domain *domain;
+ struct iommu_group *group;
+ struct kmem_cache *pt_pool;
+};
+
+struct sun50i_iommu_domain {
+ struct iommu_domain domain;
+
+ /* Number of devices attached to the domain */
+ refcount_t refcnt;
+
+ /* L1 Page Table */
+ u32 *dt;
+ dma_addr_t dt_dma;
+
+ struct sun50i_iommu *iommu;
+};
+
+static struct sun50i_iommu_domain *to_sun50i_domain(struct iommu_domain *domain)
+{
+ return container_of(domain, struct sun50i_iommu_domain, domain);
+}
+
+static struct sun50i_iommu *sun50i_iommu_from_dev(struct device *dev)
+{
+ return dev_iommu_priv_get(dev);
+}
+
+static u32 iommu_read(struct sun50i_iommu *iommu, u32 offset)
+{
+ return readl(iommu->base + offset);
+}
+
+static void iommu_write(struct sun50i_iommu *iommu, u32 offset, u32 value)
+{
+ writel(value, iommu->base + offset);
+}
+
+/*
+ * The Allwinner H6 IOMMU uses a 2-level page table.
+ *
+ * The first level is the usual Directory Table (DT), that consists of
+ * 4096 4-bytes Directory Table Entries (DTE), each pointing to a Page
+ * Table (PT).
+ *
+ * Each PT consits of 256 4-bytes Page Table Entries (PTE), each
+ * pointing to a 4kB page of physical memory.
+ *
+ * The IOMMU supports a single DT, pointed by the IOMMU_TTB_REG
+ * register that contains its physical address.
+ */
+
+#define SUN50I_IOVA_DTE_MASK GENMASK(31, 20)
+#define SUN50I_IOVA_PTE_MASK GENMASK(19, 12)
+#define SUN50I_IOVA_PAGE_MASK GENMASK(11, 0)
+
+static u32 sun50i_iova_get_dte_index(dma_addr_t iova)
+{
+ return FIELD_GET(SUN50I_IOVA_DTE_MASK, iova);
+}
+
+static u32 sun50i_iova_get_pte_index(dma_addr_t iova)
+{
+ return FIELD_GET(SUN50I_IOVA_PTE_MASK, iova);
+}
+
+static u32 sun50i_iova_get_page_offset(dma_addr_t iova)
+{
+ return FIELD_GET(SUN50I_IOVA_PAGE_MASK, iova);
+}
+
+/*
+ * Each Directory Table Entry has a Page Table address and a valid
+ * bit:
+
+ * +---------------------+-----------+-+
+ * | PT address | Reserved |V|
+ * +---------------------+-----------+-+
+ * 31:10 - Page Table address
+ * 9:2 - Reserved
+ * 1:0 - 1 if the entry is valid
+ */
+
+#define SUN50I_DTE_PT_ADDRESS_MASK GENMASK(31, 10)
+#define SUN50I_DTE_PT_ATTRS GENMASK(1, 0)
+#define SUN50I_DTE_PT_VALID 1
+
+static phys_addr_t sun50i_dte_get_pt_address(u32 dte)
+{
+ return (phys_addr_t)dte & SUN50I_DTE_PT_ADDRESS_MASK;
+}
+
+static bool sun50i_dte_is_pt_valid(u32 dte)
+{
+ return (dte & SUN50I_DTE_PT_ATTRS) == SUN50I_DTE_PT_VALID;
+}
+
+static u32 sun50i_mk_dte(dma_addr_t pt_dma)
+{
+ return (pt_dma & SUN50I_DTE_PT_ADDRESS_MASK) | SUN50I_DTE_PT_VALID;
+}
+
+/*
+ * Each PTE has a Page address, an authority index and a valid bit:
+ *
+ * +----------------+-----+-----+-----+---+-----+
+ * | Page address | Rsv | ACI | Rsv | V | Rsv |
+ * +----------------+-----+-----+-----+---+-----+
+ * 31:12 - Page address
+ * 11:8 - Reserved
+ * 7:4 - Authority Control Index
+ * 3:2 - Reserved
+ * 1 - 1 if the entry is valid
+ * 0 - Reserved
+ *
+ * The way permissions work is that the IOMMU has 16 "domains" that
+ * can be configured to give each masters either read or write
+ * permissions through the IOMMU_DM_AUT_CTRL_REG registers. The domain
+ * 0 seems like the default domain, and its permissions in the
+ * IOMMU_DM_AUT_CTRL_REG are only read-only, so it's not really
+ * useful to enforce any particular permission.
+ *
+ * Each page entry will then have a reference to the domain they are
+ * affected to, so that we can actually enforce them on a per-page
+ * basis.
+ *
+ * In order to make it work with the IOMMU framework, we will be using
+ * 4 different domains, starting at 1: RD_WR, RD, WR and NONE
+ * depending on the permission we want to enforce. Each domain will
+ * have each master setup in the same way, since the IOMMU framework
+ * doesn't seem to restrict page access on a per-device basis. And
+ * then we will use the relevant domain index when generating the page
+ * table entry depending on the permissions we want to be enforced.
+ */
+
+enum sun50i_iommu_aci {
+ SUN50I_IOMMU_ACI_DO_NOT_USE = 0,
+ SUN50I_IOMMU_ACI_NONE,
+ SUN50I_IOMMU_ACI_RD,
+ SUN50I_IOMMU_ACI_WR,
+ SUN50I_IOMMU_ACI_RD_WR,
+};
+
+#define SUN50I_PTE_PAGE_ADDRESS_MASK GENMASK(31, 12)
+#define SUN50I_PTE_ACI_MASK GENMASK(7, 4)
+#define SUN50I_PTE_PAGE_VALID BIT(1)
+
+static phys_addr_t sun50i_pte_get_page_address(u32 pte)
+{
+ return (phys_addr_t)pte & SUN50I_PTE_PAGE_ADDRESS_MASK;
+}
+
+static enum sun50i_iommu_aci sun50i_get_pte_aci(u32 pte)
+{
+ return FIELD_GET(SUN50I_PTE_ACI_MASK, pte);
+}
+
+static bool sun50i_pte_is_page_valid(u32 pte)
+{
+ return pte & SUN50I_PTE_PAGE_VALID;
+}
+
+static u32 sun50i_mk_pte(phys_addr_t page, int prot)
+{
+ enum sun50i_iommu_aci aci;
+ u32 flags = 0;
+
+ if (prot & (IOMMU_READ | IOMMU_WRITE))
+ aci = SUN50I_IOMMU_ACI_RD_WR;
+ else if (prot & IOMMU_READ)
+ aci = SUN50I_IOMMU_ACI_RD;
+ else if (prot & IOMMU_WRITE)
+ aci = SUN50I_IOMMU_ACI_WR;
+ else
+ aci = SUN50I_IOMMU_ACI_NONE;
+
+ flags |= FIELD_PREP(SUN50I_PTE_ACI_MASK, aci);
+ page &= SUN50I_PTE_PAGE_ADDRESS_MASK;
+ return page | flags | SUN50I_PTE_PAGE_VALID;
+}
+
+static void sun50i_table_flush(struct sun50i_iommu_domain *sun50i_domain,
+ void *vaddr, unsigned int count)
+{
+ struct sun50i_iommu *iommu = sun50i_domain->iommu;
+ dma_addr_t dma = virt_to_phys(vaddr);
+ size_t size = count * PT_ENTRY_SIZE;
+
+ dma_sync_single_for_device(iommu->dev, dma, size, DMA_TO_DEVICE);
+}
+
+static int sun50i_iommu_flush_all_tlb(struct sun50i_iommu *iommu)
+{
+ u32 reg;
+ int ret;
+
+ assert_spin_locked(&iommu->iommu_lock);
+
+ iommu_write(iommu,
+ IOMMU_TLB_FLUSH_REG,
+ IOMMU_TLB_FLUSH_PTW_CACHE |
+ IOMMU_TLB_FLUSH_MACRO_TLB |
+ IOMMU_TLB_FLUSH_MICRO_TLB(5) |
+ IOMMU_TLB_FLUSH_MICRO_TLB(4) |
+ IOMMU_TLB_FLUSH_MICRO_TLB(3) |
+ IOMMU_TLB_FLUSH_MICRO_TLB(2) |
+ IOMMU_TLB_FLUSH_MICRO_TLB(1) |
+ IOMMU_TLB_FLUSH_MICRO_TLB(0));
+
+ ret = readl_poll_timeout(iommu->base + IOMMU_TLB_FLUSH_REG,
+ reg, !reg,
+ 1, 2000);
+ if (ret)
+ dev_warn(iommu->dev, "TLB Flush timed out!\n");
+
+ return ret;
+}
+
+static int sun50i_iommu_ptw_invalidate(struct sun50i_iommu *iommu,
+ dma_addr_t iova)
+{
+ int ret;
+ u32 reg;
+
+ assert_spin_locked(&iommu->iommu_lock);
+
+ iommu_write(iommu, IOMMU_PC_IVLD_ADDR_REG, iova);
+ iommu_write(iommu, IOMMU_PC_IVLD_ENABLE_REG,
+ IOMMU_PC_IVLD_ENABLE_ENABLE);
+
+ ret = readl_poll_timeout(iommu->base + IOMMU_PC_IVLD_ENABLE_REG,
+ reg, !(reg & IOMMU_PC_IVLD_ENABLE_ENABLE),
+ 1, 2000);
+ if (ret)
+ dev_err(iommu->dev, "PTW cache invalid timed out\n");
+
+ return ret;
+}
+
+static void sun50i_iommu_flush_iotlb_all(struct iommu_domain *domain)
+{
+ struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
+ struct sun50i_iommu *iommu = sun50i_domain->iommu;
+ unsigned long flags;
+
+ /*
+ * At boot, we'll have a first call into .flush_iotlb_all right after
+ * .add_device, and since we link our (single) domain to our iommu in
+ * the .attach_device callback, we don't have that pointer set.
+ *
+ * It shouldn't really be any trouble to ignore it though since we flush
+ * all caches as part of the device powerup.
+ */
+ if (!iommu)
+ return;
+
+ spin_lock_irqsave(&iommu->iommu_lock, flags);
+ sun50i_iommu_flush_all_tlb(iommu);
+ spin_unlock_irqrestore(&iommu->iommu_lock, flags);
+}
+
+static void sun50i_iommu_iotlb_sync(struct iommu_domain *domain,
+ struct iommu_iotlb_gather *gather)
+{
+ sun50i_iommu_flush_iotlb_all(domain);
+}
+
+static int sun50i_iommu_enable(struct sun50i_iommu *iommu)
+{
+ struct sun50i_iommu_domain *sun50i_domain;
+ unsigned long flags;
+ int ret;
+
+ if (!iommu->domain)
+ return 0;
+
+ sun50i_domain = to_sun50i_domain(iommu->domain);
+
+ ret = reset_control_deassert(iommu->reset);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(iommu->clk);
+ if (ret)
+ goto err_reset_assert;
+
+ spin_lock_irqsave(&iommu->iommu_lock, flags);
+
+ iommu_write(iommu, IOMMU_TTB_REG, sun50i_domain->dt_dma);
+ iommu_write(iommu, IOMMU_TLB_PREFETCH_REG,
+ IOMMU_TLB_PREFETCH_MASTER_ENABLE(0) |
+ IOMMU_TLB_PREFETCH_MASTER_ENABLE(1) |
+ IOMMU_TLB_PREFETCH_MASTER_ENABLE(2) |
+ IOMMU_TLB_PREFETCH_MASTER_ENABLE(3) |
+ IOMMU_TLB_PREFETCH_MASTER_ENABLE(4) |
+ IOMMU_TLB_PREFETCH_MASTER_ENABLE(5));
+ iommu_write(iommu, IOMMU_INT_ENABLE_REG, IOMMU_INT_MASK);
+ iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_NONE),
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 0) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 0) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 1) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 1) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 2) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 2) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 3) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 3) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 4) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 4) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 5) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 5));
+
+ iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_RD),
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 0) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 1) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 2) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 3) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 4) |
+ IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 5));
+
+ iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_WR),
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 0) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 1) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 2) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 3) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 4) |
+ IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 5));
+
+ ret = sun50i_iommu_flush_all_tlb(iommu);
+ if (ret) {
+ spin_unlock_irqrestore(&iommu->iommu_lock, flags);
+ goto err_clk_disable;
+ }
+
+ iommu_write(iommu, IOMMU_AUTO_GATING_REG, IOMMU_AUTO_GATING_ENABLE);
+ iommu_write(iommu, IOMMU_ENABLE_REG, IOMMU_ENABLE_ENABLE);
+
+ spin_unlock_irqrestore(&iommu->iommu_lock, flags);
+
+ return 0;
+
+err_clk_disable:
+ clk_disable_unprepare(iommu->clk);
+
+err_reset_assert:
+ reset_control_assert(iommu->reset);
+
+ return ret;
+}
+
+static void sun50i_iommu_disable(struct sun50i_iommu *iommu)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&iommu->iommu_lock, flags);
+
+ iommu_write(iommu, IOMMU_ENABLE_REG, 0);
+ iommu_write(iommu, IOMMU_TTB_REG, 0);
+
+ spin_unlock_irqrestore(&iommu->iommu_lock, flags);
+
+ clk_disable_unprepare(iommu->clk);
+ reset_control_assert(iommu->reset);
+}
+
+static void *sun50i_iommu_alloc_page_table(struct sun50i_iommu *iommu,
+ gfp_t gfp)
+{
+ dma_addr_t pt_dma;
+ u32 *page_table;
+
+ page_table = kmem_cache_zalloc(iommu->pt_pool, gfp);
+ if (!page_table)
+ return ERR_PTR(-ENOMEM);
+
+ pt_dma = dma_map_single(iommu->dev, page_table, PT_SIZE, DMA_TO_DEVICE);
+ if (dma_mapping_error(iommu->dev, pt_dma)) {
+ dev_err(iommu->dev, "Couldn't map L2 Page Table\n");
+ kmem_cache_free(iommu->pt_pool, page_table);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* We rely on the physical address and DMA address being the same */
+ WARN_ON(pt_dma != virt_to_phys(page_table));
+
+ return page_table;
+}
+
+static void sun50i_iommu_free_page_table(struct sun50i_iommu *iommu,
+ u32 *page_table)
+{
+ phys_addr_t pt_phys = virt_to_phys(page_table);
+
+ dma_unmap_single(iommu->dev, pt_phys, PT_SIZE, DMA_TO_DEVICE);
+ kmem_cache_free(iommu->pt_pool, page_table);
+}
+
+static u32 *sun50i_dte_get_page_table(struct sun50i_iommu_domain *sun50i_domain,
+ dma_addr_t iova, gfp_t gfp)
+{
+ struct sun50i_iommu *iommu = sun50i_domain->iommu;
+ unsigned long flags;
+ u32 *page_table;
+ u32 *dte_addr;
+ u32 old_dte;
+ u32 dte;
+
+ dte_addr = &sun50i_domain->dt[sun50i_iova_get_dte_index(iova)];
+ dte = *dte_addr;
+ if (sun50i_dte_is_pt_valid(dte)) {
+ phys_addr_t pt_phys = sun50i_dte_get_pt_address(dte);
+ return (u32 *)phys_to_virt(pt_phys);
+ }
+
+ page_table = sun50i_iommu_alloc_page_table(iommu, gfp);
+ if (IS_ERR(page_table))
+ return page_table;
+
+ dte = sun50i_mk_dte(virt_to_phys(page_table));
+ old_dte = cmpxchg(dte_addr, 0, dte);
+ if (old_dte) {
+ phys_addr_t installed_pt_phys =
+ sun50i_dte_get_pt_address(old_dte);
+ u32 *installed_pt = phys_to_virt(installed_pt_phys);
+ u32 *drop_pt = page_table;
+
+ page_table = installed_pt;
+ dte = old_dte;
+ sun50i_iommu_free_page_table(iommu, drop_pt);
+ }
+
+ sun50i_table_flush(sun50i_domain, page_table, PT_SIZE);
+ sun50i_table_flush(sun50i_domain, dte_addr, 1);
+
+ spin_lock_irqsave(&iommu->iommu_lock, flags);
+ sun50i_iommu_ptw_invalidate(iommu, iova);
+ spin_unlock_irqrestore(&iommu->iommu_lock, flags);
+
+ return page_table;
+}
+
+static int sun50i_iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+{
+ struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
+ struct sun50i_iommu *iommu = sun50i_domain->iommu;
+ u32 pte_index;
+ u32 *page_table, *pte_addr;
+ int ret = 0;
+
+ page_table = sun50i_dte_get_page_table(sun50i_domain, iova, gfp);
+ if (IS_ERR(page_table)) {
+ ret = PTR_ERR(page_table);
+ goto out;
+ }
+
+ pte_index = sun50i_iova_get_pte_index(iova);
+ pte_addr = &page_table[pte_index];
+ if (unlikely(sun50i_pte_is_page_valid(*pte_addr))) {
+ phys_addr_t page_phys = sun50i_pte_get_page_address(*pte_addr);
+ dev_err(iommu->dev,
+ "iova %pad already mapped to %pa cannot remap to %pa prot: %#x\n",
+ &iova, &page_phys, &paddr, prot);
+ ret = -EBUSY;
+ goto out;
+ }
+
+ *pte_addr = sun50i_mk_pte(paddr, prot);
+ sun50i_table_flush(sun50i_domain, pte_addr, 1);
+
+out:
+ return ret;
+}
+
+static size_t sun50i_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
+ size_t size, struct iommu_iotlb_gather *gather)
+{
+ struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
+ struct sun50i_iommu *iommu = sun50i_domain->iommu;
+ phys_addr_t pt_phys;
+ dma_addr_t pte_dma;
+ u32 *pte_addr;
+ u32 dte;
+
+ dte = sun50i_domain->dt[sun50i_iova_get_dte_index(iova)];
+ if (!sun50i_dte_is_pt_valid(dte))
+ return 0;
+
+ pt_phys = sun50i_dte_get_pt_address(dte);
+ pte_addr = (u32 *)phys_to_virt(pt_phys) + sun50i_iova_get_pte_index(iova);
+ pte_dma = pt_phys + sun50i_iova_get_pte_index(iova) * PT_ENTRY_SIZE;
+
+ if (!sun50i_pte_is_page_valid(*pte_addr))
+ return 0;
+
+ memset(pte_addr, 0, sizeof(*pte_addr));
+ sun50i_table_flush(sun50i_domain, pte_addr, 1);
+
+ spin_lock(&iommu->iommu_lock);
+ sun50i_iommu_ptw_invalidate(iommu, iova);
+ spin_unlock(&iommu->iommu_lock);
+
+ return SZ_4K;
+}
+
+static phys_addr_t sun50i_iommu_iova_to_phys(struct iommu_domain *domain,
+ dma_addr_t iova)
+{
+ struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
+ phys_addr_t pt_phys;
+ u32 *page_table;
+ u32 dte, pte;
+
+ dte = sun50i_domain->dt[sun50i_iova_get_dte_index(iova)];
+ if (!sun50i_dte_is_pt_valid(dte))
+ return 0;
+
+ pt_phys = sun50i_dte_get_pt_address(dte);
+ page_table = (u32 *)phys_to_virt(pt_phys);
+ pte = page_table[sun50i_iova_get_pte_index(iova)];
+ if (!sun50i_pte_is_page_valid(pte))
+ return 0;
+
+ return sun50i_pte_get_page_address(pte) +
+ sun50i_iova_get_page_offset(iova);
+}
+
+static struct iommu_domain *sun50i_iommu_domain_alloc(unsigned type)
+{
+ struct sun50i_iommu_domain *sun50i_domain;
+
+ if (type != IOMMU_DOMAIN_DMA &&
+ type != IOMMU_DOMAIN_IDENTITY &&
+ type != IOMMU_DOMAIN_UNMANAGED)
+ return NULL;
+
+ sun50i_domain = kzalloc(sizeof(*sun50i_domain), GFP_KERNEL);
+ if (!sun50i_domain)
+ return NULL;
+
+ if (type == IOMMU_DOMAIN_DMA &&
+ iommu_get_dma_cookie(&sun50i_domain->domain))
+ goto err_free_domain;
+
+ sun50i_domain->dt = (u32 *)__get_free_pages(GFP_KERNEL,
+ get_order(DT_SIZE));
+ if (!sun50i_domain->dt)
+ goto err_put_cookie;
+ memset(sun50i_domain->dt, 0, DT_SIZE);
+
+ refcount_set(&sun50i_domain->refcnt, 1);
+
+ sun50i_domain->domain.geometry.aperture_start = 0;
+ sun50i_domain->domain.geometry.aperture_end = DMA_BIT_MASK(32);
+ sun50i_domain->domain.geometry.force_aperture = true;
+
+ return &sun50i_domain->domain;
+
+err_put_cookie:
+ if (type == IOMMU_DOMAIN_DMA)
+ iommu_put_dma_cookie(&sun50i_domain->domain);
+
+err_free_domain:
+ kfree(sun50i_domain);
+
+ return NULL;
+}
+
+static void sun50i_iommu_domain_free(struct iommu_domain *domain)
+{
+ struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
+
+ free_pages((unsigned long)sun50i_domain->dt, get_order(DT_SIZE));
+ sun50i_domain->dt = NULL;
+
+ iommu_put_dma_cookie(domain);
+
+ kfree(sun50i_domain);
+}
+
+static int sun50i_iommu_attach_domain(struct sun50i_iommu *iommu,
+ struct sun50i_iommu_domain *sun50i_domain)
+{
+ iommu->domain = &sun50i_domain->domain;
+ sun50i_domain->iommu = iommu;
+
+ sun50i_domain->dt_dma = dma_map_single(iommu->dev, sun50i_domain->dt,
+ DT_SIZE, DMA_TO_DEVICE);
+ if (dma_mapping_error(iommu->dev, sun50i_domain->dt_dma)) {
+ dev_err(iommu->dev, "Couldn't map L1 Page Table\n");
+ return -ENOMEM;
+ }
+
+ return sun50i_iommu_enable(iommu);
+}
+
+static void sun50i_iommu_detach_domain(struct sun50i_iommu *iommu,
+ struct sun50i_iommu_domain *sun50i_domain)
+{
+ unsigned int i;
+
+ for (i = 0; i < NUM_DT_ENTRIES; i++) {
+ phys_addr_t pt_phys;
+ u32 *page_table;
+ u32 *dte_addr;
+ u32 dte;
+
+ dte_addr = &sun50i_domain->dt[i];
+ dte = *dte_addr;
+ if (!sun50i_dte_is_pt_valid(dte))
+ continue;
+
+ memset(dte_addr, 0, sizeof(*dte_addr));
+ sun50i_table_flush(sun50i_domain, dte_addr, 1);
+
+ pt_phys = sun50i_dte_get_pt_address(dte);
+ page_table = phys_to_virt(pt_phys);
+ sun50i_iommu_free_page_table(iommu, page_table);
+ }
+
+
+ sun50i_iommu_disable(iommu);
+
+ dma_unmap_single(iommu->dev, virt_to_phys(sun50i_domain->dt),
+ DT_SIZE, DMA_TO_DEVICE);
+
+ iommu->domain = NULL;
+}
+
+static void sun50i_iommu_detach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
+ struct sun50i_iommu *iommu = dev_iommu_priv_get(dev);
+
+ dev_dbg(dev, "Detaching from IOMMU domain\n");
+
+ if (iommu->domain != domain)
+ return;
+
+ if (refcount_dec_and_test(&sun50i_domain->refcnt))
+ sun50i_iommu_detach_domain(iommu, sun50i_domain);
+}
+
+static int sun50i_iommu_attach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
+ struct sun50i_iommu *iommu;
+
+ iommu = sun50i_iommu_from_dev(dev);
+ if (!iommu)
+ return -ENODEV;
+
+ dev_dbg(dev, "Attaching to IOMMU domain\n");
+
+ refcount_inc(&sun50i_domain->refcnt);
+
+ if (iommu->domain == domain)
+ return 0;
+
+ if (iommu->domain)
+ sun50i_iommu_detach_device(iommu->domain, dev);
+
+ sun50i_iommu_attach_domain(iommu, sun50i_domain);
+
+ return 0;
+}
+
+static int sun50i_iommu_add_device(struct device *dev)
+{
+ struct sun50i_iommu *iommu;
+ struct iommu_group *group;
+
+ iommu = sun50i_iommu_from_dev(dev);
+ if (!iommu)
+ return -ENODEV;
+
+ group = iommu_group_get_for_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ iommu_group_put(group);
+
+ return 0;
+}
+
+static void sun50i_iommu_remove_device(struct device *dev)
+{
+ iommu_group_remove_device(dev);
+}
+
+static struct iommu_group *sun50i_iommu_device_group(struct device *dev)
+{
+ struct sun50i_iommu *iommu = sun50i_iommu_from_dev(dev);
+
+ return iommu_group_ref_get(iommu->group);
+}
+
+static int sun50i_iommu_of_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct platform_device *iommu_pdev = of_find_device_by_node(args->np);
+ unsigned id = args->args[0];
+
+ dev_iommu_priv_set(dev, platform_get_drvdata(iommu_pdev));
+
+ return iommu_fwspec_add_ids(dev, &id, 1);
+}
+
+static struct iommu_ops sun50i_iommu_ops = {
+ .pgsize_bitmap = SZ_4K,
+ .add_device = sun50i_iommu_add_device,
+ .attach_dev = sun50i_iommu_attach_device,
+ .detach_dev = sun50i_iommu_detach_device,
+ .device_group = sun50i_iommu_device_group,
+ .domain_alloc = sun50i_iommu_domain_alloc,
+ .domain_free = sun50i_iommu_domain_free,
+ .flush_iotlb_all = sun50i_iommu_flush_iotlb_all,
+ .iotlb_sync = sun50i_iommu_iotlb_sync,
+ .iova_to_phys = sun50i_iommu_iova_to_phys,
+ .map = sun50i_iommu_map,
+ .of_xlate = sun50i_iommu_of_xlate,
+ .remove_device = sun50i_iommu_remove_device,
+ .unmap = sun50i_iommu_unmap,
+};
+
+static void sun50i_iommu_report_fault(struct sun50i_iommu *iommu,
+ unsigned master, phys_addr_t iova,
+ unsigned prot)
+{
+ dev_err(iommu->dev, "Page fault for %pad (master %d, dir %s)\n",
+ &iova, master, (prot == IOMMU_FAULT_WRITE) ? "wr" : "rd");
+
+ if (iommu->domain)
+ report_iommu_fault(iommu->domain, iommu->dev, iova, prot);
+ else
+ dev_err(iommu->dev, "Page fault while iommu not attached to any domain?\n");
+}
+
+static phys_addr_t sun50i_iommu_handle_pt_irq(struct sun50i_iommu *iommu,
+ unsigned addr_reg,
+ unsigned blame_reg)
+{
+ phys_addr_t iova;
+ unsigned master;
+ u32 blame;
+
+ assert_spin_locked(&iommu->iommu_lock);
+
+ iova = iommu_read(iommu, addr_reg);
+ blame = iommu_read(iommu, blame_reg);
+ master = ilog2(blame & IOMMU_INT_MASTER_MASK);
+
+ /*
+ * If the address is not in the page table, we can't get what
+ * operation triggered the fault. Assume it's a read
+ * operation.
+ */
+ sun50i_iommu_report_fault(iommu, master, iova, IOMMU_FAULT_READ);
+
+ return iova;
+}
+
+static phys_addr_t sun50i_iommu_handle_perm_irq(struct sun50i_iommu *iommu)
+{
+ enum sun50i_iommu_aci aci;
+ phys_addr_t iova;
+ unsigned master;
+ unsigned dir;
+ u32 blame;
+
+ assert_spin_locked(&iommu->iommu_lock);
+
+ blame = iommu_read(iommu, IOMMU_INT_STA_REG);
+ master = ilog2(blame & IOMMU_INT_MASTER_MASK);
+ iova = iommu_read(iommu, IOMMU_INT_ERR_ADDR_REG(master));
+ aci = sun50i_get_pte_aci(iommu_read(iommu,
+ IOMMU_INT_ERR_DATA_REG(master)));
+
+ switch (aci) {
+ /*
+ * If we are in the read-only domain, then it means we
+ * tried to write.
+ */
+ case SUN50I_IOMMU_ACI_RD:
+ dir = IOMMU_FAULT_WRITE;
+ break;
+
+ /*
+ * If we are in the write-only domain, then it means
+ * we tried to read.
+ */
+ case SUN50I_IOMMU_ACI_WR:
+
+ /*
+ * If we are in the domain without any permission, we
+ * can't really tell. Let's default to a read
+ * operation.
+ */
+ case SUN50I_IOMMU_ACI_NONE:
+
+ /* WTF? */
+ case SUN50I_IOMMU_ACI_RD_WR:
+ default:
+ dir = IOMMU_FAULT_READ;
+ break;
+ }
+
+ /*
+ * If the address is not in the page table, we can't get what
+ * operation triggered the fault. Assume it's a read
+ * operation.
+ */
+ sun50i_iommu_report_fault(iommu, master, iova, dir);
+
+ return iova;
+}
+
+static irqreturn_t sun50i_iommu_irq(int irq, void *dev_id)
+{
+ struct sun50i_iommu *iommu = dev_id;
+ phys_addr_t iova;
+ u32 status;
+
+ spin_lock(&iommu->iommu_lock);
+
+ status = iommu_read(iommu, IOMMU_INT_STA_REG);
+ if (!(status & IOMMU_INT_MASK)) {
+ spin_unlock(&iommu->iommu_lock);
+ return IRQ_NONE;
+ }
+
+ if (status & IOMMU_INT_INVALID_L2PG)
+ iova = sun50i_iommu_handle_pt_irq(iommu,
+ IOMMU_INT_ERR_ADDR_L2_REG,
+ IOMMU_L2PG_INT_REG);
+ else if (status & IOMMU_INT_INVALID_L1PG)
+ iova = sun50i_iommu_handle_pt_irq(iommu,
+ IOMMU_INT_ERR_ADDR_L1_REG,
+ IOMMU_L1PG_INT_REG);
+ else
+ iova = sun50i_iommu_handle_perm_irq(iommu);
+
+ iommu_write(iommu, IOMMU_INT_CLR_REG, status);
+
+ iommu_write(iommu, IOMMU_RESET_REG, ~status);
+ iommu_write(iommu, IOMMU_RESET_REG, status);
+
+ spin_unlock(&iommu->iommu_lock);
+
+ return IRQ_HANDLED;
+}
+
+static int sun50i_iommu_probe(struct platform_device *pdev)
+{
+ struct sun50i_iommu *iommu;
+ int ret, irq;
+
+ iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
+ if (!iommu)
+ return -ENOMEM;
+ spin_lock_init(&iommu->iommu_lock);
+ platform_set_drvdata(pdev, iommu);
+ iommu->dev = &pdev->dev;
+
+ iommu->pt_pool = kmem_cache_create(dev_name(&pdev->dev),
+ PT_SIZE, PT_SIZE,
+ SLAB_HWCACHE_ALIGN,
+ NULL);
+ if (!iommu->pt_pool)
+ return -ENOMEM;
+
+ iommu->group = iommu_group_alloc();
+ if (IS_ERR(iommu->group)) {
+ ret = PTR_ERR(iommu->group);
+ goto err_free_cache;
+ }
+
+ iommu->base = devm_platform_ioremap_resource(pdev, 0);
+ if (!iommu->base) {
+ ret = PTR_ERR(iommu->base);
+ goto err_free_group;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ ret = irq;
+ goto err_free_group;
+ }
+
+ iommu->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(iommu->clk)) {
+ dev_err(&pdev->dev, "Couldn't get our clock.\n");
+ ret = PTR_ERR(iommu->clk);
+ goto err_free_group;
+ }
+
+ iommu->reset = devm_reset_control_get(&pdev->dev, NULL);
+ if (IS_ERR(iommu->reset)) {
+ dev_err(&pdev->dev, "Couldn't get our reset line.\n");
+ ret = PTR_ERR(iommu->reset);
+ goto err_free_group;
+ }
+
+ ret = iommu_device_sysfs_add(&iommu->iommu, &pdev->dev,
+ NULL, dev_name(&pdev->dev));
+ if (ret)
+ goto err_free_group;
+
+ iommu_device_set_ops(&iommu->iommu, &sun50i_iommu_ops);
+ iommu_device_set_fwnode(&iommu->iommu, &pdev->dev.of_node->fwnode);
+
+ ret = iommu_device_register(&iommu->iommu);
+ if (ret)
+ goto err_remove_sysfs;
+
+ ret = devm_request_irq(&pdev->dev, irq, sun50i_iommu_irq, 0,
+ dev_name(&pdev->dev), iommu);
+ if (ret < 0)
+ goto err_unregister;
+
+ bus_set_iommu(&platform_bus_type, &sun50i_iommu_ops);
+
+ return 0;
+
+err_unregister:
+ iommu_device_unregister(&iommu->iommu);
+
+err_remove_sysfs:
+ iommu_device_sysfs_remove(&iommu->iommu);
+
+err_free_group:
+ iommu_group_put(iommu->group);
+
+err_free_cache:
+ kmem_cache_destroy(iommu->pt_pool);
+
+ return ret;
+}
+
+static const struct of_device_id sun50i_iommu_dt[] = {
+ { .compatible = "allwinner,sun50i-h6-iommu", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, sun50i_iommu_dt);
+
+static struct platform_driver sun50i_iommu_driver = {
+ .driver = {
+ .name = "sun50i-iommu",
+ .of_match_table = sun50i_iommu_dt,
+ .suppress_bind_attrs = true,
+ }
+};
+builtin_platform_driver_probe(sun50i_iommu_driver, sun50i_iommu_probe);
+
+MODULE_DESCRIPTION("Allwinner H6 IOMMU driver");
+MODULE_AUTHOR("Maxime Ripard <maxime at cerno.tech>");
+MODULE_AUTHOR("zhuxianbin <zhuxianbin at allwinnertech.com>");
+MODULE_LICENSE("Dual BSD/GPL");
--
git-series 0.9.1
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