[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] [RFC PATCH v1 1/7] iommu/arm: ipmmu-vmsa: Add IPMMU-VMSA support



From: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>

It is VMSA-compatible IOMMU that integrated in the
newest Renesas SoCs (ARM). Copy Linux IPMMU driver as is for now.
Next patches will show what is going on.

Linux driver was taken here:
git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git rcar-3.5.3

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>
CC: Julien Grall <julien.grall@xxxxxxx>
CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
---
 xen/drivers/passthrough/arm/ipmmu-vmsa.c | 1647 ++++++++++++++++++++++++++++++
 1 file changed, 1647 insertions(+)
 create mode 100644 xen/drivers/passthrough/arm/ipmmu-vmsa.c

diff --git a/xen/drivers/passthrough/arm/ipmmu-vmsa.c 
b/xen/drivers/passthrough/arm/ipmmu-vmsa.c
new file mode 100644
index 0000000..2b380ff
--- /dev/null
+++ b/xen/drivers/passthrough/arm/ipmmu-vmsa.c
@@ -0,0 +1,1647 @@
+/*
+ * IPMMU VMSA
+ *
+ * Copyright (C) 2014 Renesas Electronics Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/delay.h>
+#include <linux/dma-iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iommu.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_iommu.h>
+#include <linux/platform_device.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+
+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
+#include <asm/dma-iommu.h>
+#include <asm/pgalloc.h>
+#endif
+
+#include "io-pgtable.h"
+
+#define IPMMU_CTX_MAX 8
+
+struct ipmmu_features {
+       bool use_ns_alias_offset;
+       bool has_cache_leaf_nodes;
+       bool has_eight_ctx;
+       bool setup_imbuscr;
+       bool twobit_imttbcr_sl0;
+};
+
+#ifdef CONFIG_RCAR_DDR_BACKUP
+struct hw_register {
+       char *reg_name;
+       unsigned int reg_offset;
+       unsigned int reg_data;
+};
+#endif
+
+struct ipmmu_vmsa_device {
+       struct device *dev;
+       void __iomem *base;
+       struct list_head list;
+       const struct ipmmu_features *features;
+       bool is_leaf;
+       unsigned int num_utlbs;
+       unsigned int num_ctx;
+       spinlock_t lock;                        /* Protects ctx and domains[] */
+       DECLARE_BITMAP(ctx, IPMMU_CTX_MAX);
+       struct ipmmu_vmsa_domain *domains[IPMMU_CTX_MAX];
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       struct hw_register *reg_backup[IPMMU_CTX_MAX];
+#endif
+
+       struct dma_iommu_mapping *mapping;
+};
+
+struct ipmmu_vmsa_domain {
+       struct ipmmu_vmsa_device *mmu;
+       struct ipmmu_vmsa_device *root;
+       struct iommu_domain io_domain;
+
+       struct io_pgtable_cfg cfg;
+       struct io_pgtable_ops *iop;
+
+       unsigned int context_id;
+       spinlock_t lock;                        /* Protects mappings */
+};
+
+struct ipmmu_vmsa_archdata {
+       struct ipmmu_vmsa_device *mmu;
+       unsigned int *utlbs;
+       unsigned int num_utlbs;
+       struct device *dev;
+       struct list_head list;
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       unsigned int *utlbs_val;
+       unsigned int *asids_val;
+#endif
+};
+
+static DEFINE_SPINLOCK(ipmmu_devices_lock);
+static LIST_HEAD(ipmmu_devices);
+
+static DEFINE_SPINLOCK(ipmmu_slave_devices_lock);
+static LIST_HEAD(ipmmu_slave_devices);
+
+static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom)
+{
+       return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
+}
+
+#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
+static struct ipmmu_vmsa_archdata *to_archdata(struct device *dev)
+{
+       return dev->archdata.iommu;
+}
+static void set_archdata(struct device *dev, struct ipmmu_vmsa_archdata *p)
+{
+       dev->archdata.iommu = p;
+}
+#else
+static struct ipmmu_vmsa_archdata *to_archdata(struct device *dev)
+{
+       return NULL;
+}
+static void set_archdata(struct device *dev, struct ipmmu_vmsa_archdata *p)
+{
+}
+#endif
+
+#define TLB_LOOP_TIMEOUT               100     /* 100us */
+
+/* 
-----------------------------------------------------------------------------
+ * Registers Definition
+ */
+
+#define IM_NS_ALIAS_OFFSET             0x800
+
+#define IM_CTX_SIZE                    0x40
+
+#define IMCTR                          0x0000
+#define IMCTR_TRE                      (1 << 17)
+#define IMCTR_AFE                      (1 << 16)
+#define IMCTR_RTSEL_MASK               (3 << 4)
+#define IMCTR_RTSEL_SHIFT              4
+#define IMCTR_TREN                     (1 << 3)
+#define IMCTR_INTEN                    (1 << 2)
+#define IMCTR_FLUSH                    (1 << 1)
+#define IMCTR_MMUEN                    (1 << 0)
+
+#define IMCAAR                         0x0004
+
+#define IMTTBCR                                0x0008
+#define IMTTBCR_EAE                    (1 << 31)
+#define IMTTBCR_PMB                    (1 << 30)
+#define IMTTBCR_SH1_NON_SHAREABLE      (0 << 28)
+#define IMTTBCR_SH1_OUTER_SHAREABLE    (2 << 28)
+#define IMTTBCR_SH1_INNER_SHAREABLE    (3 << 28)
+#define IMTTBCR_SH1_MASK               (3 << 28)
+#define IMTTBCR_ORGN1_NC               (0 << 26)
+#define IMTTBCR_ORGN1_WB_WA            (1 << 26)
+#define IMTTBCR_ORGN1_WT               (2 << 26)
+#define IMTTBCR_ORGN1_WB               (3 << 26)
+#define IMTTBCR_ORGN1_MASK             (3 << 26)
+#define IMTTBCR_IRGN1_NC               (0 << 24)
+#define IMTTBCR_IRGN1_WB_WA            (1 << 24)
+#define IMTTBCR_IRGN1_WT               (2 << 24)
+#define IMTTBCR_IRGN1_WB               (3 << 24)
+#define IMTTBCR_IRGN1_MASK             (3 << 24)
+#define IMTTBCR_TSZ1_MASK              (7 << 16)
+#define IMTTBCR_TSZ1_SHIFT             16
+#define IMTTBCR_SH0_NON_SHAREABLE      (0 << 12)
+#define IMTTBCR_SH0_OUTER_SHAREABLE    (2 << 12)
+#define IMTTBCR_SH0_INNER_SHAREABLE    (3 << 12)
+#define IMTTBCR_SH0_MASK               (3 << 12)
+#define IMTTBCR_ORGN0_NC               (0 << 10)
+#define IMTTBCR_ORGN0_WB_WA            (1 << 10)
+#define IMTTBCR_ORGN0_WT               (2 << 10)
+#define IMTTBCR_ORGN0_WB               (3 << 10)
+#define IMTTBCR_ORGN0_MASK             (3 << 10)
+#define IMTTBCR_IRGN0_NC               (0 << 8)
+#define IMTTBCR_IRGN0_WB_WA            (1 << 8)
+#define IMTTBCR_IRGN0_WT               (2 << 8)
+#define IMTTBCR_IRGN0_WB               (3 << 8)
+#define IMTTBCR_IRGN0_MASK             (3 << 8)
+#define IMTTBCR_SL0_LVL_2              (0 << 4)
+#define IMTTBCR_SL0_LVL_1              (1 << 4)
+#define IMTTBCR_TSZ0_MASK              (7 << 0)
+#define IMTTBCR_TSZ0_SHIFT             O
+
+#define IMTTBCR_SL0_TWOBIT_LVL_3       (0 << 6)
+#define IMTTBCR_SL0_TWOBIT_LVL_2       (1 << 6)
+#define IMTTBCR_SL0_TWOBIT_LVL_1       (2 << 6)
+
+#define IMBUSCR                                0x000c
+#define IMBUSCR_DVM                    (1 << 2)
+#define IMBUSCR_BUSSEL_SYS             (0 << 0)
+#define IMBUSCR_BUSSEL_CCI             (1 << 0)
+#define IMBUSCR_BUSSEL_IMCAAR          (2 << 0)
+#define IMBUSCR_BUSSEL_CCI_IMCAAR      (3 << 0)
+#define IMBUSCR_BUSSEL_MASK            (3 << 0)
+
+#define IMTTLBR0                       0x0010
+#define IMTTUBR0                       0x0014
+#define IMTTLBR1                       0x0018
+#define IMTTUBR1                       0x001c
+
+#define IMSTR                          0x0020
+#define IMSTR_ERRLVL_MASK              (3 << 12)
+#define IMSTR_ERRLVL_SHIFT             12
+#define IMSTR_ERRCODE_TLB_FORMAT       (1 << 8)
+#define IMSTR_ERRCODE_ACCESS_PERM      (4 << 8)
+#define IMSTR_ERRCODE_SECURE_ACCESS    (5 << 8)
+#define IMSTR_ERRCODE_MASK             (7 << 8)
+#define IMSTR_MHIT                     (1 << 4)
+#define IMSTR_ABORT                    (1 << 2)
+#define IMSTR_PF                       (1 << 1)
+#define IMSTR_TF                       (1 << 0)
+
+#define IMMAIR0                                0x0028
+#define IMMAIR1                                0x002c
+#define IMMAIR_ATTR_MASK               0xff
+#define IMMAIR_ATTR_DEVICE             0x04
+#define IMMAIR_ATTR_NC                 0x44
+#define IMMAIR_ATTR_WBRWA              0xff
+#define IMMAIR_ATTR_SHIFT(n)           ((n) << 3)
+#define IMMAIR_ATTR_IDX_NC             0
+#define IMMAIR_ATTR_IDX_WBRWA          1
+#define IMMAIR_ATTR_IDX_DEV            2
+
+#define IMEAR                          0x0030
+
+#define IMPCTR                         0x0200
+#define IMPSTR                         0x0208
+#define IMPEAR                         0x020c
+#define IMPMBA(n)                      (0x0280 + ((n) * 4))
+#define IMPMBD(n)                      (0x02c0 + ((n) * 4))
+
+#define IMUCTR(n)                      (0x0300 + ((n) * 16))
+#define IMUCTR2(n)                     (0x0600 + ((n) * 16))
+#define IMUCTR_FIXADDEN                        (1 << 31)
+#define IMUCTR_FIXADD_MASK             (0xff << 16)
+#define IMUCTR_FIXADD_SHIFT            16
+#define IMUCTR_TTSEL_MMU(n)            ((n) << 4)
+#define IMUCTR_TTSEL_PMB               (8 << 4)
+#define IMUCTR_TTSEL_MASK              (15 << 4)
+#define IMUCTR_FLUSH                   (1 << 1)
+#define IMUCTR_MMUEN                   (1 << 0)
+
+#define IMUASID(n)                     (0x0308 + ((n) * 16))
+#define IMUASID2(n)                    (0x0608 + ((n) * 16))
+#define IMUASID_ASID8_MASK             (0xff << 8)
+#define IMUASID_ASID8_SHIFT            8
+#define IMUASID_ASID0_MASK             (0xff << 0)
+#define IMUASID_ASID0_SHIFT            0
+
+#ifdef CONFIG_RCAR_DDR_BACKUP
+#define HW_REGISTER_BACKUP_SIZE                ARRAY_SIZE(root_pgtable0_reg)
+static struct hw_register root_pgtable0_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register root_pgtable1_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register root_pgtable2_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register root_pgtable3_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register root_pgtable4_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register root_pgtable5_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register root_pgtable6_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register root_pgtable7_reg[] = {
+       {"IMTTLBR0",    IMTTLBR0,       0},
+       {"IMTTUBR0",    IMTTUBR0,       0},
+       {"IMTTBCR",     IMTTBCR,        0},
+       {"IMTTLBR1",    IMTTLBR1,       0},
+       {"IMTTUBR1",    IMTTUBR1,       0},
+       {"IMMAIR0",     IMMAIR0,        0},
+       {"IMMAIR1",     IMMAIR1,        0},
+       {"IMCTR",       IMCTR,          0},
+};
+
+static struct hw_register *root_pgtable[IPMMU_CTX_MAX] = {
+       root_pgtable0_reg,
+       root_pgtable1_reg,
+       root_pgtable2_reg,
+       root_pgtable3_reg,
+       root_pgtable4_reg,
+       root_pgtable5_reg,
+       root_pgtable6_reg,
+       root_pgtable7_reg,
+};
+
+#endif
+/* 
-----------------------------------------------------------------------------
+ * Root device handling
+ */
+
+static bool ipmmu_is_root(struct ipmmu_vmsa_device *mmu)
+{
+       if (mmu->features->has_cache_leaf_nodes)
+               return mmu->is_leaf ? false : true;
+       else
+               return true; /* older IPMMU hardware treated as single root */
+}
+
+static struct ipmmu_vmsa_device *ipmmu_find_root(struct ipmmu_vmsa_device 
*leaf)
+{
+       struct ipmmu_vmsa_device *mmu = NULL;
+
+       if (ipmmu_is_root(leaf))
+               return leaf;
+
+       spin_lock(&ipmmu_devices_lock);
+
+       list_for_each_entry(mmu, &ipmmu_devices, list) {
+               if (ipmmu_is_root(mmu))
+                       break;
+       }
+
+       spin_unlock(&ipmmu_devices_lock);
+       return mmu;
+}
+
+/* 
-----------------------------------------------------------------------------
+ * Read/Write Access
+ */
+
+static u32 ipmmu_read(struct ipmmu_vmsa_device *mmu, unsigned int offset)
+{
+       return ioread32(mmu->base + offset);
+}
+
+static void ipmmu_write(struct ipmmu_vmsa_device *mmu, unsigned int offset,
+                       u32 data)
+{
+       iowrite32(data, mmu->base + offset);
+}
+
+static u32 ipmmu_ctx_read(struct ipmmu_vmsa_domain *domain, unsigned int reg)
+{
+       return ipmmu_read(domain->root, domain->context_id * IM_CTX_SIZE + reg);
+}
+
+static void ipmmu_ctx_write(struct ipmmu_vmsa_domain *domain, unsigned int reg,
+                           u32 data)
+{
+       ipmmu_write(domain->root, domain->context_id * IM_CTX_SIZE + reg, data);
+}
+
+static void ipmmu_ctx_write2(struct ipmmu_vmsa_domain *domain, unsigned int 
reg,
+                            u32 data)
+{
+       if (domain->mmu != domain->root)
+               ipmmu_write(domain->mmu,
+                           domain->context_id * IM_CTX_SIZE + reg, data);
+
+       ipmmu_write(domain->root, domain->context_id * IM_CTX_SIZE + reg, data);
+}
+
+/* 
-----------------------------------------------------------------------------
+ * TLB and microTLB Management
+ */
+
+/* Wait for any pending TLB invalidations to complete */
+static void ipmmu_tlb_sync(struct ipmmu_vmsa_domain *domain)
+{
+       unsigned int count = 0;
+
+       while (ipmmu_ctx_read(domain, IMCTR) & IMCTR_FLUSH) {
+               cpu_relax();
+               if (++count == TLB_LOOP_TIMEOUT) {
+                       dev_err_ratelimited(domain->mmu->dev,
+                       "TLB sync timed out -- MMU may be deadlocked\n");
+                       return;
+               }
+               udelay(1);
+       }
+}
+
+static void ipmmu_tlb_invalidate(struct ipmmu_vmsa_domain *domain)
+{
+       u32 reg;
+
+       reg = ipmmu_ctx_read(domain, IMCTR);
+       reg |= IMCTR_FLUSH;
+       ipmmu_ctx_write2(domain, IMCTR, reg);
+
+       ipmmu_tlb_sync(domain);
+}
+
+/*
+ * Enable MMU translation for the microTLB.
+ */
+static void ipmmu_utlb_enable(struct ipmmu_vmsa_domain *domain,
+                             unsigned int utlb)
+{
+       struct ipmmu_vmsa_device *mmu = domain->mmu;
+       unsigned int offset;
+
+       /*
+        * TODO: Reference-count the microTLB as several bus masters can be
+        * connected to the same microTLB.
+        */
+
+       /* TODO: What should we set the ASID to ? */
+       offset = (utlb < 32) ? IMUASID(utlb) : IMUASID2(utlb - 32);
+       ipmmu_write(mmu, offset, 0);
+
+       /* TODO: Do we need to flush the microTLB ? */
+       offset = (utlb < 32) ? IMUCTR(utlb) : IMUCTR2(utlb - 32);
+       ipmmu_write(mmu, offset,
+                   IMUCTR_TTSEL_MMU(domain->context_id) | IMUCTR_FLUSH |
+                   IMUCTR_MMUEN);
+}
+
+/*
+ * Disable MMU translation for the microTLB.
+ */
+static void ipmmu_utlb_disable(struct ipmmu_vmsa_domain *domain,
+                              unsigned int utlb)
+{
+       struct ipmmu_vmsa_device *mmu = domain->mmu;
+       unsigned int offset;
+
+       offset = (utlb < 32) ? IMUCTR(utlb) : IMUCTR2(utlb - 32);
+       ipmmu_write(mmu, offset, 0);
+}
+
+static void ipmmu_tlb_flush_all(void *cookie)
+{
+       struct ipmmu_vmsa_domain *domain = cookie;
+
+       ipmmu_tlb_invalidate(domain);
+}
+
+static void ipmmu_tlb_add_flush(unsigned long iova, size_t size,
+                               size_t granule, bool leaf, void *cookie)
+{
+       /* The hardware doesn't support selective TLB flush. */
+}
+
+static struct iommu_gather_ops ipmmu_gather_ops = {
+       .tlb_flush_all = ipmmu_tlb_flush_all,
+       .tlb_add_flush = ipmmu_tlb_add_flush,
+       .tlb_sync = ipmmu_tlb_flush_all,
+};
+
+/* 
-----------------------------------------------------------------------------
+ * Domain/Context Management
+ */
+
+static int ipmmu_domain_allocate_context(struct ipmmu_vmsa_device *mmu,
+                                        struct ipmmu_vmsa_domain *domain)
+{
+       unsigned long flags;
+       int ret;
+
+       spin_lock_irqsave(&mmu->lock, flags);
+
+       ret = find_first_zero_bit(mmu->ctx, mmu->num_ctx);
+       if (ret != mmu->num_ctx) {
+               mmu->domains[ret] = domain;
+               set_bit(ret, mmu->ctx);
+       } else
+               ret = -EBUSY;
+
+       spin_unlock_irqrestore(&mmu->lock, flags);
+
+       return ret;
+}
+
+static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain)
+{
+       u64 ttbr;
+       u32 tmp;
+       int ret;
+
+       /*
+        * Allocate the page table operations.
+        *
+        * VMSA states in section B3.6.3 "Control of Secure or Non-secure memory
+        * access, Long-descriptor format" that the NStable bit being set in a
+        * table descriptor will result in the NStable and NS bits of all child
+        * entries being ignored and considered as being set. The IPMMU seems
+        * not to comply with this, as it generates a secure access page fault
+        * if any of the NStable and NS bits isn't set when running in
+        * non-secure mode.
+        */
+       domain->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS;
+       domain->cfg.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
+       domain->cfg.ias = 32;
+       domain->cfg.oas = 40;
+       domain->cfg.tlb = &ipmmu_gather_ops;
+       domain->io_domain.geometry.aperture_end = DMA_BIT_MASK(32);
+       domain->io_domain.geometry.force_aperture = true;
+       /*
+        * TODO: Add support for coherent walk through CCI with DVM and remove
+        * cache handling. For now, delegate it to the io-pgtable code.
+        */
+       domain->cfg.iommu_dev = domain->root->dev;
+
+       domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg,
+                                          domain);
+       if (!domain->iop)
+               return -EINVAL;
+
+       /*
+        * Find an unused context.
+        */
+       ret = ipmmu_domain_allocate_context(domain->root, domain);
+       if (ret < 0) {
+               free_io_pgtable_ops(domain->iop);
+               return ret;
+       }
+
+       domain->context_id = ret;
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       domain->root->reg_backup[ret] = root_pgtable[ret];
+#endif
+
+       /* TTBR0 */
+       ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr[0];
+       ipmmu_ctx_write(domain, IMTTLBR0, ttbr);
+       ipmmu_ctx_write(domain, IMTTUBR0, ttbr >> 32);
+
+       /*
+        * TTBCR
+        * We use long descriptors with inner-shareable WBWA tables and allocate
+        * the whole 32-bit VA space to TTBR0.
+        */
+
+       if (domain->root->features->twobit_imttbcr_sl0)
+               tmp = IMTTBCR_SL0_TWOBIT_LVL_1;
+       else
+               tmp = IMTTBCR_SL0_LVL_1;
+
+       ipmmu_ctx_write(domain, IMTTBCR, IMTTBCR_EAE |
+                       IMTTBCR_SH0_INNER_SHAREABLE | IMTTBCR_ORGN0_WB_WA |
+                       IMTTBCR_IRGN0_WB_WA | tmp);
+
+       /* MAIR0 */
+       ipmmu_ctx_write(domain, IMMAIR0, domain->cfg.arm_lpae_s1_cfg.mair[0]);
+
+       /* IMBUSCR */
+       if (domain->root->features->setup_imbuscr)
+               ipmmu_ctx_write(domain, IMBUSCR,
+                               ipmmu_ctx_read(domain, IMBUSCR) &
+                               ~(IMBUSCR_DVM | IMBUSCR_BUSSEL_MASK));
+       /*
+        * IMSTR
+        * Clear all interrupt flags.
+        */
+       ipmmu_ctx_write(domain, IMSTR, ipmmu_ctx_read(domain, IMSTR));
+
+       /*
+        * IMCTR
+        * Enable the MMU and interrupt generation. The long-descriptor
+        * translation table format doesn't use TEX remapping. Don't enable AF
+        * software management as we have no use for it. Flush the TLB as
+        * required when modifying the context registers.
+        */
+       ipmmu_ctx_write2(domain, IMCTR,
+                        IMCTR_INTEN | IMCTR_FLUSH | IMCTR_MMUEN);
+
+       return 0;
+}
+
+static void ipmmu_domain_free_context(struct ipmmu_vmsa_device *mmu,
+                                     unsigned int context_id)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&mmu->lock, flags);
+
+       clear_bit(context_id, mmu->ctx);
+       mmu->domains[context_id] = NULL;
+
+       spin_unlock_irqrestore(&mmu->lock, flags);
+}
+
+static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain)
+{
+       /*
+        * Disable the context. Flush the TLB as required when modifying the
+        * context registers.
+        *
+        * TODO: Is TLB flush really needed ?
+        */
+       ipmmu_ctx_write2(domain, IMCTR, IMCTR_FLUSH);
+       ipmmu_tlb_sync(domain);
+
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       domain->root->reg_backup[domain->context_id] = NULL;
+#endif
+
+       ipmmu_domain_free_context(domain->root, domain->context_id);
+}
+
+/* 
-----------------------------------------------------------------------------
+ * Fault Handling
+ */
+
+static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
+{
+       const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
+       struct ipmmu_vmsa_device *mmu = domain->mmu;
+       u32 status;
+       u32 iova;
+
+       status = ipmmu_ctx_read(domain, IMSTR);
+       if (!(status & err_mask))
+               return IRQ_NONE;
+
+       iova = ipmmu_ctx_read(domain, IMEAR);
+
+       /*
+        * Clear the error status flags. Unlike traditional interrupt flag
+        * registers that must be cleared by writing 1, this status register
+        * seems to require 0. The error address register must be read before,
+        * otherwise its value will be 0.
+        */
+       ipmmu_ctx_write(domain, IMSTR, 0);
+
+       /* Log fatal errors. */
+       if (status & IMSTR_MHIT)
+               dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%08x\n",
+                                   iova);
+       if (status & IMSTR_ABORT)
+               dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%08x\n",
+                                   iova);
+
+       if (!(status & (IMSTR_PF | IMSTR_TF)))
+               return IRQ_NONE;
+
+       /*
+        * Try to handle page faults and translation faults.
+        *
+        * TODO: We need to look up the faulty device based on the I/O VA. Use
+        * the IOMMU device for now.
+        */
+       if (!report_iommu_fault(&domain->io_domain, mmu->dev, iova, 0))
+               return IRQ_HANDLED;
+
+       dev_err_ratelimited(mmu->dev,
+                           "Unhandled fault: status 0x%08x iova 0x%08x\n",
+                           status, iova);
+
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t ipmmu_irq(int irq, void *dev)
+{
+       struct ipmmu_vmsa_device *mmu = dev;
+       irqreturn_t status = IRQ_NONE;
+       unsigned int i;
+       unsigned long flags;
+
+       spin_lock_irqsave(&mmu->lock, flags);
+
+       /*
+        * Check interrupts for all active contexts.
+        */
+       for (i = 0; i < mmu->num_ctx; i++) {
+               if (!mmu->domains[i])
+                       continue;
+               if (ipmmu_domain_irq(mmu->domains[i]) == IRQ_HANDLED)
+                       status = IRQ_HANDLED;
+       }
+
+       spin_unlock_irqrestore(&mmu->lock, flags);
+
+       return status;
+}
+
+/* 
-----------------------------------------------------------------------------
+ * IOMMU Operations
+ */
+
+static struct iommu_domain *__ipmmu_domain_alloc(unsigned type)
+{
+       struct ipmmu_vmsa_domain *domain;
+
+       domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+       if (!domain)
+               return NULL;
+
+       spin_lock_init(&domain->lock);
+
+       return &domain->io_domain;
+}
+
+static void ipmmu_domain_free(struct iommu_domain *io_domain)
+{
+       struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+       /*
+        * Free the domain resources. We assume that all devices have already
+        * been detached.
+        */
+       ipmmu_domain_destroy_context(domain);
+       free_io_pgtable_ops(domain->iop);
+       kfree(domain);
+}
+
+static int ipmmu_attach_device(struct iommu_domain *io_domain,
+                              struct device *dev)
+{
+       struct ipmmu_vmsa_archdata *archdata = to_archdata(dev);
+       struct ipmmu_vmsa_device *root, *mmu = archdata->mmu;
+       struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+       unsigned long flags;
+       unsigned int i;
+       int ret = 0;
+
+       if (!mmu) {
+               dev_err(dev, "Cannot attach to IPMMU\n");
+               return -ENXIO;
+       }
+
+       root = ipmmu_find_root(archdata->mmu);
+       if (!root) {
+               dev_err(dev, "Unable to locate root IPMMU\n");
+               return -EAGAIN;
+       }
+
+       spin_lock_irqsave(&domain->lock, flags);
+
+       if (!domain->mmu) {
+               /* The domain hasn't been used yet, initialize it. */
+               domain->mmu = mmu;
+               domain->root = root;
+               ret = ipmmu_domain_init_context(domain);
+               if (ret < 0) {
+                       dev_err(dev, "Unable to initialize IPMMU context\n");
+                       domain->mmu = NULL;
+               } else {
+                       dev_info(dev, "Using IPMMU context %u\n",
+                                domain->context_id);
+               }
+       } else if (domain->mmu != mmu) {
+               /*
+                * Something is wrong, we can't attach two devices using
+                * different IOMMUs to the same domain.
+                */
+               dev_err(dev, "Can't attach IPMMU %s to domain on IPMMU %s\n",
+                       dev_name(mmu->dev), dev_name(domain->mmu->dev));
+               ret = -EINVAL;
+       } else {
+                       dev_info(dev, "Reusing IPMMU context %u\n",
+                                domain->context_id);
+       }
+
+       spin_unlock_irqrestore(&domain->lock, flags);
+
+       if (ret < 0)
+               return ret;
+
+       for (i = 0; i < archdata->num_utlbs; ++i)
+               ipmmu_utlb_enable(domain, archdata->utlbs[i]);
+
+       return 0;
+}
+
+static void ipmmu_detach_device(struct iommu_domain *io_domain,
+                               struct device *dev)
+{
+       struct ipmmu_vmsa_archdata *archdata = to_archdata(dev);
+       struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+       unsigned int i;
+
+       for (i = 0; i < archdata->num_utlbs; ++i)
+               ipmmu_utlb_disable(domain, archdata->utlbs[i]);
+
+       /*
+        * TODO: Optimize by disabling the context when no device is attached.
+        */
+}
+
+static int ipmmu_map(struct iommu_domain *io_domain, unsigned long iova,
+                    phys_addr_t paddr, size_t size, int prot)
+{
+       struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+       if (!domain)
+               return -ENODEV;
+
+       return domain->iop->map(domain->iop, iova, paddr, size, prot);
+}
+
+static size_t ipmmu_unmap(struct iommu_domain *io_domain, unsigned long iova,
+                         size_t size)
+{
+       struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+       return domain->iop->unmap(domain->iop, iova, size);
+}
+
+static phys_addr_t ipmmu_iova_to_phys(struct iommu_domain *io_domain,
+                                     dma_addr_t iova)
+{
+       struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
+
+       /* TODO: Is locking needed ? */
+
+       return domain->iop->iova_to_phys(domain->iop, iova);
+}
+
+static struct device *ipmmu_find_sibling_device(struct device *dev)
+{
+       struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
+       struct ipmmu_vmsa_archdata *sibling_archdata = NULL;
+       bool found = false;
+
+       spin_lock(&ipmmu_slave_devices_lock);
+
+       list_for_each_entry(sibling_archdata, &ipmmu_slave_devices, list) {
+               if (archdata == sibling_archdata)
+                       continue;
+               if (sibling_archdata->mmu == archdata->mmu) {
+                       found = true;
+                       break;
+               }
+       }
+
+       spin_unlock(&ipmmu_slave_devices_lock);
+
+       return found ? sibling_archdata->dev : NULL;
+}
+
+static struct iommu_group *ipmmu_find_group(struct device *dev)
+{
+       struct iommu_group *group;
+       struct device *sibling;
+
+       sibling = ipmmu_find_sibling_device(dev);
+       if (sibling)
+               group = iommu_group_get(sibling);
+       if (!sibling || IS_ERR(group))
+               group = generic_device_group(dev);
+
+       return group;
+}
+
+static int ipmmu_find_utlbs(struct ipmmu_vmsa_device *mmu, struct device *dev,
+                           unsigned int *utlbs, unsigned int num_utlbs)
+{
+       unsigned int i;
+
+       for (i = 0; i < num_utlbs; ++i) {
+               struct of_phandle_args args;
+               int ret;
+
+               ret = of_parse_phandle_with_args(dev->of_node, "iommus",
+                                                "#iommu-cells", i, &args);
+               if (ret < 0)
+                       return ret;
+
+               of_node_put(args.np);
+
+               if (args.np != mmu->dev->of_node || args.args_count != 1)
+                       return -EINVAL;
+
+               utlbs[i] = args.args[0];
+       }
+
+       return 0;
+}
+
+static int ipmmu_init_platform_device(struct device *dev)
+{
+       struct ipmmu_vmsa_archdata *archdata;
+       struct ipmmu_vmsa_device *mmu;
+       unsigned int *utlbs;
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       unsigned int *utlbs_val, *asids_val;
+#endif
+       unsigned int i;
+       int num_utlbs;
+       int ret = -ENODEV;
+
+       /* Find the master corresponding to the device. */
+
+       num_utlbs = of_count_phandle_with_args(dev->of_node, "iommus",
+                                              "#iommu-cells");
+       if (num_utlbs < 0)
+               return -ENODEV;
+
+       utlbs = kcalloc(num_utlbs, sizeof(*utlbs), GFP_KERNEL);
+       if (!utlbs)
+               return -ENOMEM;
+
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       utlbs_val = kcalloc(num_utlbs, sizeof(*utlbs_val), GFP_KERNEL);
+       if (!utlbs_val)
+               return -ENOMEM;
+       asids_val = kcalloc(num_utlbs, sizeof(*asids_val), GFP_KERNEL);
+       if (!asids_val)
+               return -ENOMEM;
+#endif
+
+       spin_lock(&ipmmu_devices_lock);
+
+       list_for_each_entry(mmu, &ipmmu_devices, list) {
+               ret = ipmmu_find_utlbs(mmu, dev, utlbs, num_utlbs);
+               if (!ret) {
+                       /*
+                        * TODO Take a reference to the MMU to protect
+                        * against device removal.
+                        */
+                       break;
+               }
+       }
+
+       spin_unlock(&ipmmu_devices_lock);
+
+       if (ret < 0)
+               goto error;
+
+       for (i = 0; i < num_utlbs; ++i) {
+               if (utlbs[i] >= mmu->num_utlbs) {
+                       ret = -EINVAL;
+                       goto error;
+               }
+       }
+
+       archdata = kzalloc(sizeof(*archdata), GFP_KERNEL);
+       if (!archdata) {
+               ret = -ENOMEM;
+               goto error;
+       }
+
+       archdata->mmu = mmu;
+       archdata->utlbs = utlbs;
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       archdata->utlbs_val = utlbs_val;
+       archdata->asids_val = asids_val;
+#endif
+       archdata->num_utlbs = num_utlbs;
+       archdata->dev = dev;
+       set_archdata(dev, archdata);
+       return 0;
+
+error:
+       kfree(utlbs);
+       return ret;
+}
+
+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
+
+static int ipmmu_add_device(struct device *dev)
+{
+       struct ipmmu_vmsa_device *mmu = NULL;
+       struct iommu_group *group;
+       int ret;
+
+       if (to_archdata(dev)) {
+               dev_warn(dev, "IOMMU driver already assigned to device %s\n",
+                        dev_name(dev));
+               return -EINVAL;
+       }
+
+       /* Create a device group and add the device to it. */
+       group = iommu_group_alloc();
+       if (IS_ERR(group)) {
+               dev_err(dev, "Failed to allocate IOMMU group\n");
+               ret = PTR_ERR(group);
+               goto error;
+       }
+
+       ret = iommu_group_add_device(group, dev);
+       iommu_group_put(group);
+
+       if (ret < 0) {
+               dev_err(dev, "Failed to add device to IPMMU group\n");
+               group = NULL;
+               goto error;
+       }
+
+       ret = ipmmu_init_platform_device(dev);
+       if (ret < 0)
+               goto error;
+
+       /*
+        * Create the ARM mapping, used by the ARM DMA mapping core to allocate
+        * VAs. This will allocate a corresponding IOMMU domain.
+        *
+        * TODO:
+        * - Create one mapping per context (TLB).
+        * - Make the mapping size configurable ? We currently use a 2GB mapping
+        *   at a 1GB offset to ensure that NULL VAs will fault.
+        */
+       mmu = to_archdata(dev)->mmu;
+       if (!mmu->mapping) {
+               struct dma_iommu_mapping *mapping;
+
+               mapping = arm_iommu_create_mapping(&platform_bus_type,
+                                                  SZ_1G, SZ_2G);
+               if (IS_ERR(mapping)) {
+                       dev_err(mmu->dev, "failed to create ARM IOMMU 
mapping\n");
+                       ret = PTR_ERR(mapping);
+                       goto error;
+               }
+
+               mmu->mapping = mapping;
+       }
+
+       /* Attach the ARM VA mapping to the device. */
+       ret = arm_iommu_attach_device(dev, mmu->mapping);
+       if (ret < 0) {
+               dev_err(dev, "Failed to attach device to VA mapping\n");
+               goto error;
+       }
+
+       return 0;
+
+error:
+       if (mmu)
+               arm_iommu_release_mapping(mmu->mapping);
+
+       set_archdata(dev, NULL);
+
+       if (!IS_ERR_OR_NULL(group))
+               iommu_group_remove_device(dev);
+
+       return ret;
+}
+
+static void ipmmu_remove_device(struct device *dev)
+{
+       struct ipmmu_vmsa_archdata *archdata = to_archdata(dev);
+
+       arm_iommu_detach_device(dev);
+       iommu_group_remove_device(dev);
+
+       kfree(archdata->utlbs);
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       kfree(archdata->utlbs_val);
+       kfree(archdata->asids_val);
+#endif
+       kfree(archdata);
+
+       set_archdata(dev, NULL);
+}
+
+static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
+{
+       if (type != IOMMU_DOMAIN_UNMANAGED)
+               return NULL;
+
+       return __ipmmu_domain_alloc(type);
+}
+
+static const struct iommu_ops ipmmu_ops = {
+       .domain_alloc = ipmmu_domain_alloc,
+       .domain_free = ipmmu_domain_free,
+       .attach_dev = ipmmu_attach_device,
+       .detach_dev = ipmmu_detach_device,
+       .map = ipmmu_map,
+       .unmap = ipmmu_unmap,
+       .map_sg = default_iommu_map_sg,
+       .iova_to_phys = ipmmu_iova_to_phys,
+       .add_device = ipmmu_add_device,
+       .remove_device = ipmmu_remove_device,
+       .pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
+};
+
+#endif /* !CONFIG_ARM && CONFIG_IOMMU_DMA */
+
+#ifdef CONFIG_IOMMU_DMA
+
+static struct iommu_domain *ipmmu_domain_alloc_dma(unsigned type)
+{
+       struct iommu_domain *io_domain = NULL;
+
+       switch (type) {
+       case IOMMU_DOMAIN_UNMANAGED:
+               io_domain = __ipmmu_domain_alloc(type);
+               break;
+
+       case IOMMU_DOMAIN_DMA:
+               io_domain = __ipmmu_domain_alloc(type);
+               if (io_domain)
+                       iommu_get_dma_cookie(io_domain);
+               break;
+       }
+
+       return io_domain;
+}
+
+static void ipmmu_domain_free_dma(struct iommu_domain *io_domain)
+{
+       switch (io_domain->type) {
+       case IOMMU_DOMAIN_DMA:
+               iommu_put_dma_cookie(io_domain);
+               /* fall-through */
+       default:
+               ipmmu_domain_free(io_domain);
+               break;
+       }
+}
+
+static int ipmmu_add_device_dma(struct device *dev)
+{
+       struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
+       struct iommu_group *group;
+
+       /* only accept devices with iommus property */
+       if (of_count_phandle_with_args(dev->of_node, "iommus",
+                                      "#iommu-cells") < 0)
+               return -ENODEV;
+
+       group = iommu_group_get_for_dev(dev);
+       if (IS_ERR(group))
+               return PTR_ERR(group);
+
+       archdata = dev->archdata.iommu;
+       spin_lock(&ipmmu_slave_devices_lock);
+       list_add(&archdata->list, &ipmmu_slave_devices);
+       spin_unlock(&ipmmu_slave_devices_lock);
+       return 0;
+}
+
+static void ipmmu_remove_device_dma(struct device *dev)
+{
+       struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu;
+
+       spin_lock(&ipmmu_slave_devices_lock);
+       list_del(&archdata->list);
+       spin_unlock(&ipmmu_slave_devices_lock);
+
+       iommu_group_remove_device(dev);
+}
+
+static struct iommu_group *ipmmu_device_group_dma(struct device *dev)
+{
+       struct iommu_group *group;
+       int ret;
+
+       ret = ipmmu_init_platform_device(dev);
+       if (!ret)
+               group = ipmmu_find_group(dev);
+       else
+               group = ERR_PTR(ret);
+
+       return group;
+}
+
+static int ipmmu_of_xlate_dma(struct device *dev,
+                             struct of_phandle_args *spec)
+{
+       /* If the IPMMU device is disabled in DT then return error
+        * to make sure the of_iommu code does not install ops
+        * even though the iommu device is disabled
+        */
+       if (!of_device_is_available(spec->np))
+               return -ENODEV;
+
+       return 0;
+}
+
+static const struct iommu_ops ipmmu_ops = {
+       .domain_alloc = ipmmu_domain_alloc_dma,
+       .domain_free = ipmmu_domain_free_dma,
+       .attach_dev = ipmmu_attach_device,
+       .detach_dev = ipmmu_detach_device,
+       .map = ipmmu_map,
+       .unmap = ipmmu_unmap,
+       .map_sg = default_iommu_map_sg,
+       .iova_to_phys = ipmmu_iova_to_phys,
+       .add_device = ipmmu_add_device_dma,
+       .remove_device = ipmmu_remove_device_dma,
+       .device_group = ipmmu_device_group_dma,
+       .pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
+       .of_xlate = ipmmu_of_xlate_dma,
+};
+
+#endif /* CONFIG_IOMMU_DMA */
+
+/* 
-----------------------------------------------------------------------------
+ * Probe/remove and init
+ */
+
+static void ipmmu_device_reset(struct ipmmu_vmsa_device *mmu)
+{
+       unsigned int i;
+
+       /* Disable all contexts. */
+       for (i = 0; i < mmu->num_ctx; ++i)
+               ipmmu_write(mmu, i * IM_CTX_SIZE + IMCTR, 0);
+}
+
+static const struct ipmmu_features ipmmu_features_default = {
+       .use_ns_alias_offset = true,
+       .has_cache_leaf_nodes = false,
+       .has_eight_ctx = false,
+       .setup_imbuscr = true,
+       .twobit_imttbcr_sl0 = false,
+};
+
+static const struct ipmmu_features ipmmu_features_rcar_gen3 = {
+       .use_ns_alias_offset = false,
+       .has_cache_leaf_nodes = true,
+       .has_eight_ctx = true,
+       .setup_imbuscr = false,
+       .twobit_imttbcr_sl0 = true,
+};
+
+static const struct of_device_id ipmmu_of_ids[] = {
+       {
+               .compatible = "renesas,ipmmu-vmsa",
+               .data = &ipmmu_features_default,
+       }, {
+               .compatible = "renesas,ipmmu-r8a7795",
+               .data = &ipmmu_features_rcar_gen3,
+       }, {
+               .compatible = "renesas,ipmmu-r8a7796",
+               .data = &ipmmu_features_rcar_gen3,
+       }, {
+               /* Terminator */
+       },
+};
+
+MODULE_DEVICE_TABLE(of, ipmmu_of_ids);
+
+static int ipmmu_probe(struct platform_device *pdev)
+{
+       struct ipmmu_vmsa_device *mmu;
+       const struct of_device_id *match;
+       struct resource *res;
+       int irq;
+       int ret;
+
+       match = of_match_node(ipmmu_of_ids, pdev->dev.of_node);
+       if (!match)
+               return -EINVAL;
+
+       mmu = devm_kzalloc(&pdev->dev, sizeof(*mmu), GFP_KERNEL);
+       if (!mmu) {
+               dev_err(&pdev->dev, "cannot allocate device data\n");
+               return -ENOMEM;
+       }
+
+       mmu->dev = &pdev->dev;
+       mmu->num_utlbs = 48;
+       spin_lock_init(&mmu->lock);
+       bitmap_zero(mmu->ctx, IPMMU_CTX_MAX);
+       mmu->features = match->data;
+       dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+
+       /* Map I/O memory and request IRQ. */
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       mmu->base = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(mmu->base))
+               return PTR_ERR(mmu->base);
+
+       /*
+        * The IPMMU has two register banks, for secure and non-secure modes.
+        * The bank mapped at the beginning of the IPMMU address space
+        * corresponds to the running mode of the CPU. When running in secure
+        * mode the non-secure register bank is also available at an offset.
+        *
+        * Secure mode operation isn't clearly documented and is thus currently
+        * not implemented in the driver. Furthermore, preliminary tests of
+        * non-secure operation with the main register bank were not successful.
+        * Offset the registers base unconditionally to point to the non-secure
+        * alias space for now.
+        */
+       if (mmu->features->use_ns_alias_offset)
+               mmu->base += IM_NS_ALIAS_OFFSET;
+
+       /*
+        * The number of contexts varies with generation and instance.
+        * Newer SoCs get a total of 8 contexts enabled, older ones just one.
+        */
+       if (mmu->features->has_eight_ctx)
+               mmu->num_ctx = 8;
+       else
+               mmu->num_ctx = 1;
+
+       WARN_ON(mmu->num_ctx > IPMMU_CTX_MAX);
+
+       irq = platform_get_irq(pdev, 0);
+
+       /*
+        * Determine if this IPMMU instance is a leaf device by checking
+        * if the renesas,ipmmu-main property exists or not.
+        */
+       if (mmu->features->has_cache_leaf_nodes &&
+           of_find_property(pdev->dev.of_node, "renesas,ipmmu-main", NULL))
+               mmu->is_leaf = true;
+
+       /* Root devices have mandatory IRQs */
+       if (ipmmu_is_root(mmu)) {
+               if (irq < 0) {
+                       dev_err(&pdev->dev, "no IRQ found\n");
+                       return irq;
+               }
+
+               ret = devm_request_irq(&pdev->dev, irq, ipmmu_irq, 0,
+                                      dev_name(&pdev->dev), mmu);
+               if (ret < 0) {
+                       dev_err(&pdev->dev, "failed to request IRQ %d\n", irq);
+                       return ret;
+               }
+
+               ipmmu_device_reset(mmu);
+       }
+
+       /*
+        * We can't create the ARM mapping here as it requires the bus to have
+        * an IOMMU, which only happens when bus_set_iommu() is called in
+        * ipmmu_init() after the probe function returns.
+        */
+
+       spin_lock(&ipmmu_devices_lock);
+       list_add(&mmu->list, &ipmmu_devices);
+       spin_unlock(&ipmmu_devices_lock);
+
+       platform_set_drvdata(pdev, mmu);
+
+       return 0;
+}
+
+static int ipmmu_remove(struct platform_device *pdev)
+{
+       struct ipmmu_vmsa_device *mmu = platform_get_drvdata(pdev);
+
+       spin_lock(&ipmmu_devices_lock);
+       list_del(&mmu->list);
+       spin_unlock(&ipmmu_devices_lock);
+
+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
+       arm_iommu_release_mapping(mmu->mapping);
+#endif
+
+       ipmmu_device_reset(mmu);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_RCAR_DDR_BACKUP
+static int ipmmu_utlbs_backup(struct ipmmu_vmsa_device *mmu)
+{
+       unsigned int i;
+       struct ipmmu_vmsa_device *slave_mmu = NULL;
+       struct ipmmu_vmsa_archdata *slave_dev = NULL;
+
+       pr_debug("%s: Handle UTLB backup\n", dev_name(mmu->dev));
+
+       spin_lock(&ipmmu_slave_devices_lock);
+
+       list_for_each_entry(slave_dev, &ipmmu_slave_devices, list) {
+               slave_mmu = slave_dev->mmu;
+
+               if (slave_mmu != mmu)
+                       continue;
+
+               for (i = 0; i < slave_dev->num_utlbs; ++i) {
+                       slave_dev->utlbs_val[i] =
+                               ipmmu_read(slave_mmu,
+                                       IMUCTR(slave_dev->utlbs[i]));
+                       slave_dev->asids_val[i] =
+                               ipmmu_read(slave_mmu,
+                                       IMUASID(slave_dev->utlbs[i]));
+                       pr_debug("%d: Backup UTLB[%d]: 0x%x, ASID[%d]: %d\n",
+                               i, slave_dev->utlbs[i], slave_dev->utlbs_val[i],
+                               slave_dev->utlbs[i],
+                               slave_dev->asids_val[i]);
+               }
+       }
+
+       spin_unlock(&ipmmu_slave_devices_lock);
+
+       return 0;
+}
+
+static int ipmmu_utlbs_restore(struct ipmmu_vmsa_device *mmu)
+{
+       unsigned int i;
+       struct ipmmu_vmsa_device *slave_mmu = NULL;
+       struct ipmmu_vmsa_archdata *slave_dev = NULL;
+
+       pr_debug("%s: Handle UTLB restore\n", dev_name(mmu->dev));
+
+       spin_lock(&ipmmu_slave_devices_lock);
+
+       list_for_each_entry(slave_dev, &ipmmu_slave_devices, list) {
+               slave_mmu = slave_dev->mmu;
+
+               if (slave_mmu != mmu)
+                       continue;
+
+               for (i = 0; i < slave_dev->num_utlbs; ++i) {
+                       ipmmu_write(slave_mmu, IMUASID(slave_dev->utlbs[i]),
+                                       slave_dev->asids_val[i]);
+                       ipmmu_write(slave_mmu,
+                               IMUCTR(slave_dev->utlbs[i]),
+                               (slave_dev->utlbs_val[i] | IMUCTR_FLUSH));
+                       pr_debug("%d: Restore UTLB[%d]: 0x%x, ASID[%d]: %d\n",
+                               i, slave_dev->utlbs[i],
+                               ipmmu_read(slave_mmu,
+                                       IMUCTR(slave_dev->utlbs[i])),
+                               slave_dev->utlbs[i],
+                               ipmmu_read(slave_mmu,
+                               IMUASID(slave_dev->utlbs[i])));
+               }
+       }
+
+       spin_unlock(&ipmmu_slave_devices_lock);
+
+       return 0;
+}
+
+static int ipmmu_domain_backup_context(struct ipmmu_vmsa_domain *domain)
+{
+       struct ipmmu_vmsa_device *mmu = domain->root;
+       struct hw_register *reg = mmu->reg_backup[domain->context_id];
+       unsigned int i;
+
+       pr_info("%s: Handle domain context backup\n", dev_name(mmu->dev));
+
+       for (i = 0; i < HW_REGISTER_BACKUP_SIZE; i++) {
+               reg[i].reg_data = ipmmu_ctx_read(domain, reg[i].reg_offset);
+
+               pr_info("%s: reg_data 0x%x, reg_offset 0x%x\n",
+                               reg[i].reg_name,
+                               reg[i].reg_data,
+                               reg[i].reg_offset);
+       }
+
+       return 0;
+}
+
+static int ipmmu_domain_restore_context(struct ipmmu_vmsa_domain *domain)
+{
+       struct ipmmu_vmsa_device *mmu = domain->root;
+       struct hw_register *reg = mmu->reg_backup[domain->context_id];
+       unsigned int i;
+
+       pr_info("%s: Handle domain context restore\n", dev_name(mmu->dev));
+
+       for (i = 0; i < HW_REGISTER_BACKUP_SIZE; i++) {
+               if (reg[i].reg_offset != IMCTR) {
+                       ipmmu_ctx_write(domain,
+                               reg[i].reg_offset,
+                               reg[i].reg_data);
+
+                       pr_info("%s: reg_data 0x%x, reg_offset 0x%x\n",
+                               reg[i].reg_name,
+                               ipmmu_ctx_read(domain, reg[i].reg_offset),
+                               reg[i].reg_offset);
+
+               } else {
+                       ipmmu_ctx_write2(domain,
+                               reg[i].reg_offset,
+                               reg[i].reg_data | IMCTR_FLUSH);
+
+                       pr_info("%s: reg_data 0x%x, reg_offset 0x%x\n",
+                               reg[i].reg_name,
+                               ipmmu_ctx_read(domain,
+                                       reg[i].reg_offset),
+                               reg[i].reg_offset);
+               }
+       }
+
+       return 0;
+}
+#endif
+
+static int ipmmu_suspend(struct device *dev)
+{
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       int ctx;
+       unsigned int i;
+       struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
+
+       pr_debug("%s: %s\n", __func__, dev_name(dev));
+
+       /* Only backup UTLB in IPMMU cache devices*/
+       if (!ipmmu_is_root(mmu))
+               ipmmu_utlbs_backup(mmu);
+
+       ctx = find_first_zero_bit(mmu->ctx, mmu->num_ctx);
+
+       for (i = 0; i < ctx; i++) {
+               pr_info("Handle ctx %d\n", i);
+               ipmmu_domain_backup_context(mmu->domains[i]);
+       }
+#endif
+
+       return 0;
+}
+
+static int ipmmu_resume(struct device *dev)
+{
+#ifdef CONFIG_RCAR_DDR_BACKUP
+       int ctx;
+       unsigned int i;
+       struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
+
+       pr_debug("%s: %s\n", __func__, dev_name(dev));
+
+       ctx = find_first_zero_bit(mmu->ctx, mmu->num_ctx);
+
+       for (i = 0; i < ctx; i++) {
+               pr_info("Handle ctx %d\n", i);
+               ipmmu_domain_restore_context(mmu->domains[i]);
+       }
+
+       /* Only backup UTLB in IPMMU cache devices*/
+       if (!ipmmu_is_root(mmu))
+               ipmmu_utlbs_restore(mmu);
+#endif
+
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(ipmmu_pm_ops,
+                       ipmmu_suspend, ipmmu_resume);
+#define DEV_PM_OPS (&ipmmu_pm_ops)
+#else
+#define DEV_PM_OPS NULL
+#endif /* CONFIG_PM_SLEEP */
+
+static struct platform_driver ipmmu_driver = {
+       .driver = {
+               .name = "ipmmu-vmsa",
+               .pm     = DEV_PM_OPS,
+               .of_match_table = of_match_ptr(ipmmu_of_ids),
+       },
+       .probe = ipmmu_probe,
+       .remove = ipmmu_remove,
+};
+
+static int __init ipmmu_init(void)
+{
+       static bool setup_done;
+       int ret;
+
+       if (setup_done)
+               return 0;
+
+       ret = platform_driver_register(&ipmmu_driver);
+       if (ret < 0)
+               return ret;
+
+#if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
+       if (!iommu_present(&platform_bus_type))
+               bus_set_iommu(&platform_bus_type, &ipmmu_ops);
+#endif
+
+       setup_done = true;
+       return 0;
+}
+
+static void __exit ipmmu_exit(void)
+{
+       return platform_driver_unregister(&ipmmu_driver);
+}
+
+subsys_initcall(ipmmu_init);
+module_exit(ipmmu_exit);
+
+#ifdef CONFIG_IOMMU_DMA
+static int __init ipmmu_vmsa_iommu_of_setup(struct device_node *np)
+{
+       static const struct iommu_ops *ops = &ipmmu_ops;
+
+       ipmmu_init();
+
+       of_iommu_set_ops(np, (struct iommu_ops *)ops);
+       if (!iommu_present(&platform_bus_type))
+               bus_set_iommu(&platform_bus_type, ops);
+
+       return 0;
+}
+
+IOMMU_OF_DECLARE(ipmmu_vmsa_iommu_of, "renesas,ipmmu-vmsa",
+                ipmmu_vmsa_iommu_of_setup);
+IOMMU_OF_DECLARE(ipmmu_r8a7795_iommu_of, "renesas,ipmmu-r8a7795",
+                ipmmu_vmsa_iommu_of_setup);
+IOMMU_OF_DECLARE(ipmmu_r8a7796_iommu_of, "renesas,ipmmu-r8a7796",
+                ipmmu_vmsa_iommu_of_setup);
+#endif
+
+MODULE_DESCRIPTION("IOMMU API for Renesas VMSA-compatible IPMMU");
+MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.