v4.19.13 snapshot.
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
new file mode 100644
index 0000000..d2fb347
--- /dev/null
+++ b/drivers/iommu/omap-iommu.c
@@ -0,0 +1,1599 @@
+/*
+ * omap iommu: tlb and pagetable primitives
+ *
+ * Copyright (C) 2008-2010 Nokia Corporation
+ * Copyright (C) 2013-2017 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
+ * Paul Mundt and Toshihiro Kobayashi
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/iommu.h>
+#include <linux/omap-iommu.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_iommu.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#include <linux/platform_data/iommu-omap.h>
+
+#include "omap-iopgtable.h"
+#include "omap-iommu.h"
+
+static const struct iommu_ops omap_iommu_ops;
+
+#define to_iommu(dev) \
+ ((struct omap_iommu *)platform_get_drvdata(to_platform_device(dev)))
+
+/* bitmap of the page sizes currently supported */
+#define OMAP_IOMMU_PGSIZES (SZ_4K | SZ_64K | SZ_1M | SZ_16M)
+
+#define MMU_LOCK_BASE_SHIFT 10
+#define MMU_LOCK_BASE_MASK (0x1f << MMU_LOCK_BASE_SHIFT)
+#define MMU_LOCK_BASE(x) \
+ ((x & MMU_LOCK_BASE_MASK) >> MMU_LOCK_BASE_SHIFT)
+
+#define MMU_LOCK_VICT_SHIFT 4
+#define MMU_LOCK_VICT_MASK (0x1f << MMU_LOCK_VICT_SHIFT)
+#define MMU_LOCK_VICT(x) \
+ ((x & MMU_LOCK_VICT_MASK) >> MMU_LOCK_VICT_SHIFT)
+
+static struct platform_driver omap_iommu_driver;
+static struct kmem_cache *iopte_cachep;
+
+/**
+ * to_omap_domain - Get struct omap_iommu_domain from generic iommu_domain
+ * @dom: generic iommu domain handle
+ **/
+static struct omap_iommu_domain *to_omap_domain(struct iommu_domain *dom)
+{
+ return container_of(dom, struct omap_iommu_domain, domain);
+}
+
+/**
+ * omap_iommu_save_ctx - Save registers for pm off-mode support
+ * @dev: client device
+ **/
+void omap_iommu_save_ctx(struct device *dev)
+{
+ struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+ struct omap_iommu *obj;
+ u32 *p;
+ int i;
+
+ if (!arch_data)
+ return;
+
+ while (arch_data->iommu_dev) {
+ obj = arch_data->iommu_dev;
+ p = obj->ctx;
+ for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
+ p[i] = iommu_read_reg(obj, i * sizeof(u32));
+ dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i,
+ p[i]);
+ }
+ arch_data++;
+ }
+}
+EXPORT_SYMBOL_GPL(omap_iommu_save_ctx);
+
+/**
+ * omap_iommu_restore_ctx - Restore registers for pm off-mode support
+ * @dev: client device
+ **/
+void omap_iommu_restore_ctx(struct device *dev)
+{
+ struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+ struct omap_iommu *obj;
+ u32 *p;
+ int i;
+
+ if (!arch_data)
+ return;
+
+ while (arch_data->iommu_dev) {
+ obj = arch_data->iommu_dev;
+ p = obj->ctx;
+ for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
+ iommu_write_reg(obj, p[i], i * sizeof(u32));
+ dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i,
+ p[i]);
+ }
+ arch_data++;
+ }
+}
+EXPORT_SYMBOL_GPL(omap_iommu_restore_ctx);
+
+static void dra7_cfg_dspsys_mmu(struct omap_iommu *obj, bool enable)
+{
+ u32 val, mask;
+
+ if (!obj->syscfg)
+ return;
+
+ mask = (1 << (obj->id * DSP_SYS_MMU_CONFIG_EN_SHIFT));
+ val = enable ? mask : 0;
+ regmap_update_bits(obj->syscfg, DSP_SYS_MMU_CONFIG, mask, val);
+}
+
+static void __iommu_set_twl(struct omap_iommu *obj, bool on)
+{
+ u32 l = iommu_read_reg(obj, MMU_CNTL);
+
+ if (on)
+ iommu_write_reg(obj, MMU_IRQ_TWL_MASK, MMU_IRQENABLE);
+ else
+ iommu_write_reg(obj, MMU_IRQ_TLB_MISS_MASK, MMU_IRQENABLE);
+
+ l &= ~MMU_CNTL_MASK;
+ if (on)
+ l |= (MMU_CNTL_MMU_EN | MMU_CNTL_TWL_EN);
+ else
+ l |= (MMU_CNTL_MMU_EN);
+
+ iommu_write_reg(obj, l, MMU_CNTL);
+}
+
+static int omap2_iommu_enable(struct omap_iommu *obj)
+{
+ u32 l, pa;
+
+ if (!obj->iopgd || !IS_ALIGNED((u32)obj->iopgd, SZ_16K))
+ return -EINVAL;
+
+ pa = virt_to_phys(obj->iopgd);
+ if (!IS_ALIGNED(pa, SZ_16K))
+ return -EINVAL;
+
+ l = iommu_read_reg(obj, MMU_REVISION);
+ dev_info(obj->dev, "%s: version %d.%d\n", obj->name,
+ (l >> 4) & 0xf, l & 0xf);
+
+ iommu_write_reg(obj, pa, MMU_TTB);
+
+ dra7_cfg_dspsys_mmu(obj, true);
+
+ if (obj->has_bus_err_back)
+ iommu_write_reg(obj, MMU_GP_REG_BUS_ERR_BACK_EN, MMU_GP_REG);
+
+ __iommu_set_twl(obj, true);
+
+ return 0;
+}
+
+static void omap2_iommu_disable(struct omap_iommu *obj)
+{
+ u32 l = iommu_read_reg(obj, MMU_CNTL);
+
+ l &= ~MMU_CNTL_MASK;
+ iommu_write_reg(obj, l, MMU_CNTL);
+ dra7_cfg_dspsys_mmu(obj, false);
+
+ dev_dbg(obj->dev, "%s is shutting down\n", obj->name);
+}
+
+static int iommu_enable(struct omap_iommu *obj)
+{
+ int err;
+ struct platform_device *pdev = to_platform_device(obj->dev);
+ struct iommu_platform_data *pdata = dev_get_platdata(&pdev->dev);
+
+ if (pdata && pdata->deassert_reset) {
+ err = pdata->deassert_reset(pdev, pdata->reset_name);
+ if (err) {
+ dev_err(obj->dev, "deassert_reset failed: %d\n", err);
+ return err;
+ }
+ }
+
+ pm_runtime_get_sync(obj->dev);
+
+ err = omap2_iommu_enable(obj);
+
+ return err;
+}
+
+static void iommu_disable(struct omap_iommu *obj)
+{
+ struct platform_device *pdev = to_platform_device(obj->dev);
+ struct iommu_platform_data *pdata = dev_get_platdata(&pdev->dev);
+
+ omap2_iommu_disable(obj);
+
+ pm_runtime_put_sync(obj->dev);
+
+ if (pdata && pdata->assert_reset)
+ pdata->assert_reset(pdev, pdata->reset_name);
+}
+
+/*
+ * TLB operations
+ */
+static u32 iotlb_cr_to_virt(struct cr_regs *cr)
+{
+ u32 page_size = cr->cam & MMU_CAM_PGSZ_MASK;
+ u32 mask = get_cam_va_mask(cr->cam & page_size);
+
+ return cr->cam & mask;
+}
+
+static u32 get_iopte_attr(struct iotlb_entry *e)
+{
+ u32 attr;
+
+ attr = e->mixed << 5;
+ attr |= e->endian;
+ attr |= e->elsz >> 3;
+ attr <<= (((e->pgsz == MMU_CAM_PGSZ_4K) ||
+ (e->pgsz == MMU_CAM_PGSZ_64K)) ? 0 : 6);
+ return attr;
+}
+
+static u32 iommu_report_fault(struct omap_iommu *obj, u32 *da)
+{
+ u32 status, fault_addr;
+
+ status = iommu_read_reg(obj, MMU_IRQSTATUS);
+ status &= MMU_IRQ_MASK;
+ if (!status) {
+ *da = 0;
+ return 0;
+ }
+
+ fault_addr = iommu_read_reg(obj, MMU_FAULT_AD);
+ *da = fault_addr;
+
+ iommu_write_reg(obj, status, MMU_IRQSTATUS);
+
+ return status;
+}
+
+void iotlb_lock_get(struct omap_iommu *obj, struct iotlb_lock *l)
+{
+ u32 val;
+
+ val = iommu_read_reg(obj, MMU_LOCK);
+
+ l->base = MMU_LOCK_BASE(val);
+ l->vict = MMU_LOCK_VICT(val);
+}
+
+void iotlb_lock_set(struct omap_iommu *obj, struct iotlb_lock *l)
+{
+ u32 val;
+
+ val = (l->base << MMU_LOCK_BASE_SHIFT);
+ val |= (l->vict << MMU_LOCK_VICT_SHIFT);
+
+ iommu_write_reg(obj, val, MMU_LOCK);
+}
+
+static void iotlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr)
+{
+ cr->cam = iommu_read_reg(obj, MMU_READ_CAM);
+ cr->ram = iommu_read_reg(obj, MMU_READ_RAM);
+}
+
+static void iotlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr)
+{
+ iommu_write_reg(obj, cr->cam | MMU_CAM_V, MMU_CAM);
+ iommu_write_reg(obj, cr->ram, MMU_RAM);
+
+ iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
+ iommu_write_reg(obj, 1, MMU_LD_TLB);
+}
+
+/* only used in iotlb iteration for-loop */
+struct cr_regs __iotlb_read_cr(struct omap_iommu *obj, int n)
+{
+ struct cr_regs cr;
+ struct iotlb_lock l;
+
+ iotlb_lock_get(obj, &l);
+ l.vict = n;
+ iotlb_lock_set(obj, &l);
+ iotlb_read_cr(obj, &cr);
+
+ return cr;
+}
+
+#ifdef PREFETCH_IOTLB
+static struct cr_regs *iotlb_alloc_cr(struct omap_iommu *obj,
+ struct iotlb_entry *e)
+{
+ struct cr_regs *cr;
+
+ if (!e)
+ return NULL;
+
+ if (e->da & ~(get_cam_va_mask(e->pgsz))) {
+ dev_err(obj->dev, "%s:\twrong alignment: %08x\n", __func__,
+ e->da);
+ return ERR_PTR(-EINVAL);
+ }
+
+ cr = kmalloc(sizeof(*cr), GFP_KERNEL);
+ if (!cr)
+ return ERR_PTR(-ENOMEM);
+
+ cr->cam = (e->da & MMU_CAM_VATAG_MASK) | e->prsvd | e->pgsz | e->valid;
+ cr->ram = e->pa | e->endian | e->elsz | e->mixed;
+
+ return cr;
+}
+
+/**
+ * load_iotlb_entry - Set an iommu tlb entry
+ * @obj: target iommu
+ * @e: an iommu tlb entry info
+ **/
+static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
+{
+ int err = 0;
+ struct iotlb_lock l;
+ struct cr_regs *cr;
+
+ if (!obj || !obj->nr_tlb_entries || !e)
+ return -EINVAL;
+
+ pm_runtime_get_sync(obj->dev);
+
+ iotlb_lock_get(obj, &l);
+ if (l.base == obj->nr_tlb_entries) {
+ dev_warn(obj->dev, "%s: preserve entries full\n", __func__);
+ err = -EBUSY;
+ goto out;
+ }
+ if (!e->prsvd) {
+ int i;
+ struct cr_regs tmp;
+
+ for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp)
+ if (!iotlb_cr_valid(&tmp))
+ break;
+
+ if (i == obj->nr_tlb_entries) {
+ dev_dbg(obj->dev, "%s: full: no entry\n", __func__);
+ err = -EBUSY;
+ goto out;
+ }
+
+ iotlb_lock_get(obj, &l);
+ } else {
+ l.vict = l.base;
+ iotlb_lock_set(obj, &l);
+ }
+
+ cr = iotlb_alloc_cr(obj, e);
+ if (IS_ERR(cr)) {
+ pm_runtime_put_sync(obj->dev);
+ return PTR_ERR(cr);
+ }
+
+ iotlb_load_cr(obj, cr);
+ kfree(cr);
+
+ if (e->prsvd)
+ l.base++;
+ /* increment victim for next tlb load */
+ if (++l.vict == obj->nr_tlb_entries)
+ l.vict = l.base;
+ iotlb_lock_set(obj, &l);
+out:
+ pm_runtime_put_sync(obj->dev);
+ return err;
+}
+
+#else /* !PREFETCH_IOTLB */
+
+static int load_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
+{
+ return 0;
+}
+
+#endif /* !PREFETCH_IOTLB */
+
+static int prefetch_iotlb_entry(struct omap_iommu *obj, struct iotlb_entry *e)
+{
+ return load_iotlb_entry(obj, e);
+}
+
+/**
+ * flush_iotlb_page - Clear an iommu tlb entry
+ * @obj: target iommu
+ * @da: iommu device virtual address
+ *
+ * Clear an iommu tlb entry which includes 'da' address.
+ **/
+static void flush_iotlb_page(struct omap_iommu *obj, u32 da)
+{
+ int i;
+ struct cr_regs cr;
+
+ pm_runtime_get_sync(obj->dev);
+
+ for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, cr) {
+ u32 start;
+ size_t bytes;
+
+ if (!iotlb_cr_valid(&cr))
+ continue;
+
+ start = iotlb_cr_to_virt(&cr);
+ bytes = iopgsz_to_bytes(cr.cam & 3);
+
+ if ((start <= da) && (da < start + bytes)) {
+ dev_dbg(obj->dev, "%s: %08x<=%08x(%x)\n",
+ __func__, start, da, bytes);
+ iotlb_load_cr(obj, &cr);
+ iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
+ break;
+ }
+ }
+ pm_runtime_put_sync(obj->dev);
+
+ if (i == obj->nr_tlb_entries)
+ dev_dbg(obj->dev, "%s: no page for %08x\n", __func__, da);
+}
+
+/**
+ * flush_iotlb_all - Clear all iommu tlb entries
+ * @obj: target iommu
+ **/
+static void flush_iotlb_all(struct omap_iommu *obj)
+{
+ struct iotlb_lock l;
+
+ pm_runtime_get_sync(obj->dev);
+
+ l.base = 0;
+ l.vict = 0;
+ iotlb_lock_set(obj, &l);
+
+ iommu_write_reg(obj, 1, MMU_GFLUSH);
+
+ pm_runtime_put_sync(obj->dev);
+}
+
+/*
+ * H/W pagetable operations
+ */
+static void flush_iopte_range(struct device *dev, dma_addr_t dma,
+ unsigned long offset, int num_entries)
+{
+ size_t size = num_entries * sizeof(u32);
+
+ dma_sync_single_range_for_device(dev, dma, offset, size, DMA_TO_DEVICE);
+}
+
+static void iopte_free(struct omap_iommu *obj, u32 *iopte, bool dma_valid)
+{
+ dma_addr_t pt_dma;
+
+ /* Note: freed iopte's must be clean ready for re-use */
+ if (iopte) {
+ if (dma_valid) {
+ pt_dma = virt_to_phys(iopte);
+ dma_unmap_single(obj->dev, pt_dma, IOPTE_TABLE_SIZE,
+ DMA_TO_DEVICE);
+ }
+
+ kmem_cache_free(iopte_cachep, iopte);
+ }
+}
+
+static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd,
+ dma_addr_t *pt_dma, u32 da)
+{
+ u32 *iopte;
+ unsigned long offset = iopgd_index(da) * sizeof(da);
+
+ /* a table has already existed */
+ if (*iopgd)
+ goto pte_ready;
+
+ /*
+ * do the allocation outside the page table lock
+ */
+ spin_unlock(&obj->page_table_lock);
+ iopte = kmem_cache_zalloc(iopte_cachep, GFP_KERNEL);
+ spin_lock(&obj->page_table_lock);
+
+ if (!*iopgd) {
+ if (!iopte)
+ return ERR_PTR(-ENOMEM);
+
+ *pt_dma = dma_map_single(obj->dev, iopte, IOPTE_TABLE_SIZE,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(obj->dev, *pt_dma)) {
+ dev_err(obj->dev, "DMA map error for L2 table\n");
+ iopte_free(obj, iopte, false);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /*
+ * we rely on dma address and the physical address to be
+ * the same for mapping the L2 table
+ */
+ if (WARN_ON(*pt_dma != virt_to_phys(iopte))) {
+ dev_err(obj->dev, "DMA translation error for L2 table\n");
+ dma_unmap_single(obj->dev, *pt_dma, IOPTE_TABLE_SIZE,
+ DMA_TO_DEVICE);
+ iopte_free(obj, iopte, false);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ *iopgd = virt_to_phys(iopte) | IOPGD_TABLE;
+
+ flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
+ dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte);
+ } else {
+ /* We raced, free the reduniovant table */
+ iopte_free(obj, iopte, false);
+ }
+
+pte_ready:
+ iopte = iopte_offset(iopgd, da);
+ *pt_dma = iopgd_page_paddr(iopgd);
+ dev_vdbg(obj->dev,
+ "%s: da:%08x pgd:%p *pgd:%08x pte:%p *pte:%08x\n",
+ __func__, da, iopgd, *iopgd, iopte, *iopte);
+
+ return iopte;
+}
+
+static int iopgd_alloc_section(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
+{
+ u32 *iopgd = iopgd_offset(obj, da);
+ unsigned long offset = iopgd_index(da) * sizeof(da);
+
+ if ((da | pa) & ~IOSECTION_MASK) {
+ dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
+ __func__, da, pa, IOSECTION_SIZE);
+ return -EINVAL;
+ }
+
+ *iopgd = (pa & IOSECTION_MASK) | prot | IOPGD_SECTION;
+ flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
+ return 0;
+}
+
+static int iopgd_alloc_super(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
+{
+ u32 *iopgd = iopgd_offset(obj, da);
+ unsigned long offset = iopgd_index(da) * sizeof(da);
+ int i;
+
+ if ((da | pa) & ~IOSUPER_MASK) {
+ dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
+ __func__, da, pa, IOSUPER_SIZE);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < 16; i++)
+ *(iopgd + i) = (pa & IOSUPER_MASK) | prot | IOPGD_SUPER;
+ flush_iopte_range(obj->dev, obj->pd_dma, offset, 16);
+ return 0;
+}
+
+static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
+{
+ u32 *iopgd = iopgd_offset(obj, da);
+ dma_addr_t pt_dma;
+ u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da);
+ unsigned long offset = iopte_index(da) * sizeof(da);
+
+ if (IS_ERR(iopte))
+ return PTR_ERR(iopte);
+
+ *iopte = (pa & IOPAGE_MASK) | prot | IOPTE_SMALL;
+ flush_iopte_range(obj->dev, pt_dma, offset, 1);
+
+ dev_vdbg(obj->dev, "%s: da:%08x pa:%08x pte:%p *pte:%08x\n",
+ __func__, da, pa, iopte, *iopte);
+
+ return 0;
+}
+
+static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
+{
+ u32 *iopgd = iopgd_offset(obj, da);
+ dma_addr_t pt_dma;
+ u32 *iopte = iopte_alloc(obj, iopgd, &pt_dma, da);
+ unsigned long offset = iopte_index(da) * sizeof(da);
+ int i;
+
+ if ((da | pa) & ~IOLARGE_MASK) {
+ dev_err(obj->dev, "%s: %08x:%08x should aligned on %08lx\n",
+ __func__, da, pa, IOLARGE_SIZE);
+ return -EINVAL;
+ }
+
+ if (IS_ERR(iopte))
+ return PTR_ERR(iopte);
+
+ for (i = 0; i < 16; i++)
+ *(iopte + i) = (pa & IOLARGE_MASK) | prot | IOPTE_LARGE;
+ flush_iopte_range(obj->dev, pt_dma, offset, 16);
+ return 0;
+}
+
+static int
+iopgtable_store_entry_core(struct omap_iommu *obj, struct iotlb_entry *e)
+{
+ int (*fn)(struct omap_iommu *, u32, u32, u32);
+ u32 prot;
+ int err;
+
+ if (!obj || !e)
+ return -EINVAL;
+
+ switch (e->pgsz) {
+ case MMU_CAM_PGSZ_16M:
+ fn = iopgd_alloc_super;
+ break;
+ case MMU_CAM_PGSZ_1M:
+ fn = iopgd_alloc_section;
+ break;
+ case MMU_CAM_PGSZ_64K:
+ fn = iopte_alloc_large;
+ break;
+ case MMU_CAM_PGSZ_4K:
+ fn = iopte_alloc_page;
+ break;
+ default:
+ fn = NULL;
+ break;
+ }
+
+ if (WARN_ON(!fn))
+ return -EINVAL;
+
+ prot = get_iopte_attr(e);
+
+ spin_lock(&obj->page_table_lock);
+ err = fn(obj, e->da, e->pa, prot);
+ spin_unlock(&obj->page_table_lock);
+
+ return err;
+}
+
+/**
+ * omap_iopgtable_store_entry - Make an iommu pte entry
+ * @obj: target iommu
+ * @e: an iommu tlb entry info
+ **/
+static int
+omap_iopgtable_store_entry(struct omap_iommu *obj, struct iotlb_entry *e)
+{
+ int err;
+
+ flush_iotlb_page(obj, e->da);
+ err = iopgtable_store_entry_core(obj, e);
+ if (!err)
+ prefetch_iotlb_entry(obj, e);
+ return err;
+}
+
+/**
+ * iopgtable_lookup_entry - Lookup an iommu pte entry
+ * @obj: target iommu
+ * @da: iommu device virtual address
+ * @ppgd: iommu pgd entry pointer to be returned
+ * @ppte: iommu pte entry pointer to be returned
+ **/
+static void
+iopgtable_lookup_entry(struct omap_iommu *obj, u32 da, u32 **ppgd, u32 **ppte)
+{
+ u32 *iopgd, *iopte = NULL;
+
+ iopgd = iopgd_offset(obj, da);
+ if (!*iopgd)
+ goto out;
+
+ if (iopgd_is_table(*iopgd))
+ iopte = iopte_offset(iopgd, da);
+out:
+ *ppgd = iopgd;
+ *ppte = iopte;
+}
+
+static size_t iopgtable_clear_entry_core(struct omap_iommu *obj, u32 da)
+{
+ size_t bytes;
+ u32 *iopgd = iopgd_offset(obj, da);
+ int nent = 1;
+ dma_addr_t pt_dma;
+ unsigned long pd_offset = iopgd_index(da) * sizeof(da);
+ unsigned long pt_offset = iopte_index(da) * sizeof(da);
+
+ if (!*iopgd)
+ return 0;
+
+ if (iopgd_is_table(*iopgd)) {
+ int i;
+ u32 *iopte = iopte_offset(iopgd, da);
+
+ bytes = IOPTE_SIZE;
+ if (*iopte & IOPTE_LARGE) {
+ nent *= 16;
+ /* rewind to the 1st entry */
+ iopte = iopte_offset(iopgd, (da & IOLARGE_MASK));
+ }
+ bytes *= nent;
+ memset(iopte, 0, nent * sizeof(*iopte));
+ pt_dma = iopgd_page_paddr(iopgd);
+ flush_iopte_range(obj->dev, pt_dma, pt_offset, nent);
+
+ /*
+ * do table walk to check if this table is necessary or not
+ */
+ iopte = iopte_offset(iopgd, 0);
+ for (i = 0; i < PTRS_PER_IOPTE; i++)
+ if (iopte[i])
+ goto out;
+
+ iopte_free(obj, iopte, true);
+ nent = 1; /* for the next L1 entry */
+ } else {
+ bytes = IOPGD_SIZE;
+ if ((*iopgd & IOPGD_SUPER) == IOPGD_SUPER) {
+ nent *= 16;
+ /* rewind to the 1st entry */
+ iopgd = iopgd_offset(obj, (da & IOSUPER_MASK));
+ }
+ bytes *= nent;
+ }
+ memset(iopgd, 0, nent * sizeof(*iopgd));
+ flush_iopte_range(obj->dev, obj->pd_dma, pd_offset, nent);
+out:
+ return bytes;
+}
+
+/**
+ * iopgtable_clear_entry - Remove an iommu pte entry
+ * @obj: target iommu
+ * @da: iommu device virtual address
+ **/
+static size_t iopgtable_clear_entry(struct omap_iommu *obj, u32 da)
+{
+ size_t bytes;
+
+ spin_lock(&obj->page_table_lock);
+
+ bytes = iopgtable_clear_entry_core(obj, da);
+ flush_iotlb_page(obj, da);
+
+ spin_unlock(&obj->page_table_lock);
+
+ return bytes;
+}
+
+static void iopgtable_clear_entry_all(struct omap_iommu *obj)
+{
+ unsigned long offset;
+ int i;
+
+ spin_lock(&obj->page_table_lock);
+
+ for (i = 0; i < PTRS_PER_IOPGD; i++) {
+ u32 da;
+ u32 *iopgd;
+
+ da = i << IOPGD_SHIFT;
+ iopgd = iopgd_offset(obj, da);
+ offset = iopgd_index(da) * sizeof(da);
+
+ if (!*iopgd)
+ continue;
+
+ if (iopgd_is_table(*iopgd))
+ iopte_free(obj, iopte_offset(iopgd, 0), true);
+
+ *iopgd = 0;
+ flush_iopte_range(obj->dev, obj->pd_dma, offset, 1);
+ }
+
+ flush_iotlb_all(obj);
+
+ spin_unlock(&obj->page_table_lock);
+}
+
+/*
+ * Device IOMMU generic operations
+ */
+static irqreturn_t iommu_fault_handler(int irq, void *data)
+{
+ u32 da, errs;
+ u32 *iopgd, *iopte;
+ struct omap_iommu *obj = data;
+ struct iommu_domain *domain = obj->domain;
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+
+ if (!omap_domain->dev)
+ return IRQ_NONE;
+
+ errs = iommu_report_fault(obj, &da);
+ if (errs == 0)
+ return IRQ_HANDLED;
+
+ /* Fault callback or TLB/PTE Dynamic loading */
+ if (!report_iommu_fault(domain, obj->dev, da, 0))
+ return IRQ_HANDLED;
+
+ iommu_write_reg(obj, 0, MMU_IRQENABLE);
+
+ iopgd = iopgd_offset(obj, da);
+
+ if (!iopgd_is_table(*iopgd)) {
+ dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:px%08x\n",
+ obj->name, errs, da, iopgd, *iopgd);
+ return IRQ_NONE;
+ }
+
+ iopte = iopte_offset(iopgd, da);
+
+ dev_err(obj->dev, "%s: errs:0x%08x da:0x%08x pgd:0x%p *pgd:0x%08x pte:0x%p *pte:0x%08x\n",
+ obj->name, errs, da, iopgd, *iopgd, iopte, *iopte);
+
+ return IRQ_NONE;
+}
+
+/**
+ * omap_iommu_attach() - attach iommu device to an iommu domain
+ * @obj: target omap iommu device
+ * @iopgd: page table
+ **/
+static int omap_iommu_attach(struct omap_iommu *obj, u32 *iopgd)
+{
+ int err;
+
+ spin_lock(&obj->iommu_lock);
+
+ obj->pd_dma = dma_map_single(obj->dev, iopgd, IOPGD_TABLE_SIZE,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(obj->dev, obj->pd_dma)) {
+ dev_err(obj->dev, "DMA map error for L1 table\n");
+ err = -ENOMEM;
+ goto out_err;
+ }
+
+ obj->iopgd = iopgd;
+ err = iommu_enable(obj);
+ if (err)
+ goto out_err;
+ flush_iotlb_all(obj);
+
+ spin_unlock(&obj->iommu_lock);
+
+ dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
+
+ return 0;
+
+out_err:
+ spin_unlock(&obj->iommu_lock);
+
+ return err;
+}
+
+/**
+ * omap_iommu_detach - release iommu device
+ * @obj: target iommu
+ **/
+static void omap_iommu_detach(struct omap_iommu *obj)
+{
+ if (!obj || IS_ERR(obj))
+ return;
+
+ spin_lock(&obj->iommu_lock);
+
+ dma_unmap_single(obj->dev, obj->pd_dma, IOPGD_TABLE_SIZE,
+ DMA_TO_DEVICE);
+ iommu_disable(obj);
+ obj->pd_dma = 0;
+ obj->iopgd = NULL;
+
+ spin_unlock(&obj->iommu_lock);
+
+ dev_dbg(obj->dev, "%s: %s\n", __func__, obj->name);
+}
+
+static bool omap_iommu_can_register(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+
+ if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu"))
+ return true;
+
+ /*
+ * restrict IOMMU core registration only for processor-port MDMA MMUs
+ * on DRA7 DSPs
+ */
+ if ((!strcmp(dev_name(&pdev->dev), "40d01000.mmu")) ||
+ (!strcmp(dev_name(&pdev->dev), "41501000.mmu")))
+ return true;
+
+ return false;
+}
+
+static int omap_iommu_dra7_get_dsp_system_cfg(struct platform_device *pdev,
+ struct omap_iommu *obj)
+{
+ struct device_node *np = pdev->dev.of_node;
+ int ret;
+
+ if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu"))
+ return 0;
+
+ if (!of_property_read_bool(np, "ti,syscon-mmuconfig")) {
+ dev_err(&pdev->dev, "ti,syscon-mmuconfig property is missing\n");
+ return -EINVAL;
+ }
+
+ obj->syscfg =
+ syscon_regmap_lookup_by_phandle(np, "ti,syscon-mmuconfig");
+ if (IS_ERR(obj->syscfg)) {
+ /* can fail with -EPROBE_DEFER */
+ ret = PTR_ERR(obj->syscfg);
+ return ret;
+ }
+
+ if (of_property_read_u32_index(np, "ti,syscon-mmuconfig", 1,
+ &obj->id)) {
+ dev_err(&pdev->dev, "couldn't get the IOMMU instance id within subsystem\n");
+ return -EINVAL;
+ }
+
+ if (obj->id != 0 && obj->id != 1) {
+ dev_err(&pdev->dev, "invalid IOMMU instance id\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * OMAP Device MMU(IOMMU) detection
+ */
+static int omap_iommu_probe(struct platform_device *pdev)
+{
+ int err = -ENODEV;
+ int irq;
+ struct omap_iommu *obj;
+ struct resource *res;
+ struct device_node *of = pdev->dev.of_node;
+
+ if (!of) {
+ pr_err("%s: only DT-based devices are supported\n", __func__);
+ return -ENODEV;
+ }
+
+ obj = devm_kzalloc(&pdev->dev, sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL);
+ if (!obj)
+ return -ENOMEM;
+
+ obj->name = dev_name(&pdev->dev);
+ obj->nr_tlb_entries = 32;
+ err = of_property_read_u32(of, "ti,#tlb-entries", &obj->nr_tlb_entries);
+ if (err && err != -EINVAL)
+ return err;
+ if (obj->nr_tlb_entries != 32 && obj->nr_tlb_entries != 8)
+ return -EINVAL;
+ if (of_find_property(of, "ti,iommu-bus-err-back", NULL))
+ obj->has_bus_err_back = MMU_GP_REG_BUS_ERR_BACK_EN;
+
+ obj->dev = &pdev->dev;
+ obj->ctx = (void *)obj + sizeof(*obj);
+
+ spin_lock_init(&obj->iommu_lock);
+ spin_lock_init(&obj->page_table_lock);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ obj->regbase = devm_ioremap_resource(obj->dev, res);
+ if (IS_ERR(obj->regbase))
+ return PTR_ERR(obj->regbase);
+
+ err = omap_iommu_dra7_get_dsp_system_cfg(pdev, obj);
+ if (err)
+ return err;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return -ENODEV;
+
+ err = devm_request_irq(obj->dev, irq, iommu_fault_handler, IRQF_SHARED,
+ dev_name(obj->dev), obj);
+ if (err < 0)
+ return err;
+ platform_set_drvdata(pdev, obj);
+
+ if (omap_iommu_can_register(pdev)) {
+ obj->group = iommu_group_alloc();
+ if (IS_ERR(obj->group))
+ return PTR_ERR(obj->group);
+
+ err = iommu_device_sysfs_add(&obj->iommu, obj->dev, NULL,
+ obj->name);
+ if (err)
+ goto out_group;
+
+ iommu_device_set_ops(&obj->iommu, &omap_iommu_ops);
+
+ err = iommu_device_register(&obj->iommu);
+ if (err)
+ goto out_sysfs;
+ }
+
+ pm_runtime_irq_safe(obj->dev);
+ pm_runtime_enable(obj->dev);
+
+ omap_iommu_debugfs_add(obj);
+
+ dev_info(&pdev->dev, "%s registered\n", obj->name);
+
+ return 0;
+
+out_sysfs:
+ iommu_device_sysfs_remove(&obj->iommu);
+out_group:
+ iommu_group_put(obj->group);
+ return err;
+}
+
+static int omap_iommu_remove(struct platform_device *pdev)
+{
+ struct omap_iommu *obj = platform_get_drvdata(pdev);
+
+ if (obj->group) {
+ iommu_group_put(obj->group);
+ obj->group = NULL;
+
+ iommu_device_sysfs_remove(&obj->iommu);
+ iommu_device_unregister(&obj->iommu);
+ }
+
+ omap_iommu_debugfs_remove(obj);
+
+ pm_runtime_disable(obj->dev);
+
+ dev_info(&pdev->dev, "%s removed\n", obj->name);
+ return 0;
+}
+
+static const struct of_device_id omap_iommu_of_match[] = {
+ { .compatible = "ti,omap2-iommu" },
+ { .compatible = "ti,omap4-iommu" },
+ { .compatible = "ti,dra7-iommu" },
+ { .compatible = "ti,dra7-dsp-iommu" },
+ {},
+};
+
+static struct platform_driver omap_iommu_driver = {
+ .probe = omap_iommu_probe,
+ .remove = omap_iommu_remove,
+ .driver = {
+ .name = "omap-iommu",
+ .of_match_table = of_match_ptr(omap_iommu_of_match),
+ },
+};
+
+static u32 iotlb_init_entry(struct iotlb_entry *e, u32 da, u32 pa, int pgsz)
+{
+ memset(e, 0, sizeof(*e));
+
+ e->da = da;
+ e->pa = pa;
+ e->valid = MMU_CAM_V;
+ e->pgsz = pgsz;
+ e->endian = MMU_RAM_ENDIAN_LITTLE;
+ e->elsz = MMU_RAM_ELSZ_8;
+ e->mixed = 0;
+
+ return iopgsz_to_bytes(e->pgsz);
+}
+
+static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
+ phys_addr_t pa, size_t bytes, int prot)
+{
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+ struct device *dev = omap_domain->dev;
+ struct omap_iommu_device *iommu;
+ struct omap_iommu *oiommu;
+ struct iotlb_entry e;
+ int omap_pgsz;
+ u32 ret = -EINVAL;
+ int i;
+
+ omap_pgsz = bytes_to_iopgsz(bytes);
+ if (omap_pgsz < 0) {
+ dev_err(dev, "invalid size to map: %d\n", bytes);
+ return -EINVAL;
+ }
+
+ dev_dbg(dev, "mapping da 0x%lx to pa %pa size 0x%x\n", da, &pa, bytes);
+
+ iotlb_init_entry(&e, da, pa, omap_pgsz);
+
+ iommu = omap_domain->iommus;
+ for (i = 0; i < omap_domain->num_iommus; i++, iommu++) {
+ oiommu = iommu->iommu_dev;
+ ret = omap_iopgtable_store_entry(oiommu, &e);
+ if (ret) {
+ dev_err(dev, "omap_iopgtable_store_entry failed: %d\n",
+ ret);
+ break;
+ }
+ }
+
+ if (ret) {
+ while (i--) {
+ iommu--;
+ oiommu = iommu->iommu_dev;
+ iopgtable_clear_entry(oiommu, da);
+ }
+ }
+
+ return ret;
+}
+
+static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
+ size_t size)
+{
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+ struct device *dev = omap_domain->dev;
+ struct omap_iommu_device *iommu;
+ struct omap_iommu *oiommu;
+ bool error = false;
+ size_t bytes = 0;
+ int i;
+
+ dev_dbg(dev, "unmapping da 0x%lx size %u\n", da, size);
+
+ iommu = omap_domain->iommus;
+ for (i = 0; i < omap_domain->num_iommus; i++, iommu++) {
+ oiommu = iommu->iommu_dev;
+ bytes = iopgtable_clear_entry(oiommu, da);
+ if (!bytes)
+ error = true;
+ }
+
+ /*
+ * simplify return - we are only checking if any of the iommus
+ * reported an error, but not if all of them are unmapping the
+ * same number of entries. This should not occur due to the
+ * mirror programming.
+ */
+ return error ? 0 : bytes;
+}
+
+static int omap_iommu_count(struct device *dev)
+{
+ struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+ int count = 0;
+
+ while (arch_data->iommu_dev) {
+ count++;
+ arch_data++;
+ }
+
+ return count;
+}
+
+/* caller should call cleanup if this function fails */
+static int omap_iommu_attach_init(struct device *dev,
+ struct omap_iommu_domain *odomain)
+{
+ struct omap_iommu_device *iommu;
+ int i;
+
+ odomain->num_iommus = omap_iommu_count(dev);
+ if (!odomain->num_iommus)
+ return -EINVAL;
+
+ odomain->iommus = kcalloc(odomain->num_iommus, sizeof(*iommu),
+ GFP_ATOMIC);
+ if (!odomain->iommus)
+ return -ENOMEM;
+
+ iommu = odomain->iommus;
+ for (i = 0; i < odomain->num_iommus; i++, iommu++) {
+ iommu->pgtable = kzalloc(IOPGD_TABLE_SIZE, GFP_ATOMIC);
+ if (!iommu->pgtable)
+ return -ENOMEM;
+
+ /*
+ * should never fail, but please keep this around to ensure
+ * we keep the hardware happy
+ */
+ if (WARN_ON(!IS_ALIGNED((long)iommu->pgtable,
+ IOPGD_TABLE_SIZE)))
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void omap_iommu_detach_fini(struct omap_iommu_domain *odomain)
+{
+ int i;
+ struct omap_iommu_device *iommu = odomain->iommus;
+
+ for (i = 0; iommu && i < odomain->num_iommus; i++, iommu++)
+ kfree(iommu->pgtable);
+
+ kfree(odomain->iommus);
+ odomain->num_iommus = 0;
+ odomain->iommus = NULL;
+}
+
+static int
+omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
+{
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+ struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+ struct omap_iommu_device *iommu;
+ struct omap_iommu *oiommu;
+ int ret = 0;
+ int i;
+
+ if (!arch_data || !arch_data->iommu_dev) {
+ dev_err(dev, "device doesn't have an associated iommu\n");
+ return -EINVAL;
+ }
+
+ spin_lock(&omap_domain->lock);
+
+ /* only a single client device can be attached to a domain */
+ if (omap_domain->dev) {
+ dev_err(dev, "iommu domain is already attached\n");
+ ret = -EBUSY;
+ goto out;
+ }
+
+ ret = omap_iommu_attach_init(dev, omap_domain);
+ if (ret) {
+ dev_err(dev, "failed to allocate required iommu data %d\n",
+ ret);
+ goto init_fail;
+ }
+
+ iommu = omap_domain->iommus;
+ for (i = 0; i < omap_domain->num_iommus; i++, iommu++, arch_data++) {
+ /* configure and enable the omap iommu */
+ oiommu = arch_data->iommu_dev;
+ ret = omap_iommu_attach(oiommu, iommu->pgtable);
+ if (ret) {
+ dev_err(dev, "can't get omap iommu: %d\n", ret);
+ goto attach_fail;
+ }
+
+ oiommu->domain = domain;
+ iommu->iommu_dev = oiommu;
+ }
+
+ omap_domain->dev = dev;
+
+ goto out;
+
+attach_fail:
+ while (i--) {
+ iommu--;
+ arch_data--;
+ oiommu = iommu->iommu_dev;
+ omap_iommu_detach(oiommu);
+ iommu->iommu_dev = NULL;
+ oiommu->domain = NULL;
+ }
+init_fail:
+ omap_iommu_detach_fini(omap_domain);
+out:
+ spin_unlock(&omap_domain->lock);
+ return ret;
+}
+
+static void _omap_iommu_detach_dev(struct omap_iommu_domain *omap_domain,
+ struct device *dev)
+{
+ struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+ struct omap_iommu_device *iommu = omap_domain->iommus;
+ struct omap_iommu *oiommu;
+ int i;
+
+ if (!omap_domain->dev) {
+ dev_err(dev, "domain has no attached device\n");
+ return;
+ }
+
+ /* only a single device is supported per domain for now */
+ if (omap_domain->dev != dev) {
+ dev_err(dev, "invalid attached device\n");
+ return;
+ }
+
+ /*
+ * cleanup in the reverse order of attachment - this addresses
+ * any h/w dependencies between multiple instances, if any
+ */
+ iommu += (omap_domain->num_iommus - 1);
+ arch_data += (omap_domain->num_iommus - 1);
+ for (i = 0; i < omap_domain->num_iommus; i++, iommu--, arch_data--) {
+ oiommu = iommu->iommu_dev;
+ iopgtable_clear_entry_all(oiommu);
+
+ omap_iommu_detach(oiommu);
+ iommu->iommu_dev = NULL;
+ oiommu->domain = NULL;
+ }
+
+ omap_iommu_detach_fini(omap_domain);
+
+ omap_domain->dev = NULL;
+}
+
+static void omap_iommu_detach_dev(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+
+ spin_lock(&omap_domain->lock);
+ _omap_iommu_detach_dev(omap_domain, dev);
+ spin_unlock(&omap_domain->lock);
+}
+
+static struct iommu_domain *omap_iommu_domain_alloc(unsigned type)
+{
+ struct omap_iommu_domain *omap_domain;
+
+ if (type != IOMMU_DOMAIN_UNMANAGED)
+ return NULL;
+
+ omap_domain = kzalloc(sizeof(*omap_domain), GFP_KERNEL);
+ if (!omap_domain)
+ return NULL;
+
+ spin_lock_init(&omap_domain->lock);
+
+ omap_domain->domain.geometry.aperture_start = 0;
+ omap_domain->domain.geometry.aperture_end = (1ULL << 32) - 1;
+ omap_domain->domain.geometry.force_aperture = true;
+
+ return &omap_domain->domain;
+}
+
+static void omap_iommu_domain_free(struct iommu_domain *domain)
+{
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+
+ /*
+ * An iommu device is still attached
+ * (currently, only one device can be attached) ?
+ */
+ if (omap_domain->dev)
+ _omap_iommu_detach_dev(omap_domain, omap_domain->dev);
+
+ kfree(omap_domain);
+}
+
+static phys_addr_t omap_iommu_iova_to_phys(struct iommu_domain *domain,
+ dma_addr_t da)
+{
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+ struct omap_iommu_device *iommu = omap_domain->iommus;
+ struct omap_iommu *oiommu = iommu->iommu_dev;
+ struct device *dev = oiommu->dev;
+ u32 *pgd, *pte;
+ phys_addr_t ret = 0;
+
+ /*
+ * all the iommus within the domain will have identical programming,
+ * so perform the lookup using just the first iommu
+ */
+ iopgtable_lookup_entry(oiommu, da, &pgd, &pte);
+
+ if (pte) {
+ if (iopte_is_small(*pte))
+ ret = omap_iommu_translate(*pte, da, IOPTE_MASK);
+ else if (iopte_is_large(*pte))
+ ret = omap_iommu_translate(*pte, da, IOLARGE_MASK);
+ else
+ dev_err(dev, "bogus pte 0x%x, da 0x%llx", *pte,
+ (unsigned long long)da);
+ } else {
+ if (iopgd_is_section(*pgd))
+ ret = omap_iommu_translate(*pgd, da, IOSECTION_MASK);
+ else if (iopgd_is_super(*pgd))
+ ret = omap_iommu_translate(*pgd, da, IOSUPER_MASK);
+ else
+ dev_err(dev, "bogus pgd 0x%x, da 0x%llx", *pgd,
+ (unsigned long long)da);
+ }
+
+ return ret;
+}
+
+static int omap_iommu_add_device(struct device *dev)
+{
+ struct omap_iommu_arch_data *arch_data, *tmp;
+ struct omap_iommu *oiommu;
+ struct iommu_group *group;
+ struct device_node *np;
+ struct platform_device *pdev;
+ int num_iommus, i;
+ int ret;
+
+ /*
+ * Allocate the archdata iommu structure for DT-based devices.
+ *
+ * TODO: Simplify this when removing non-DT support completely from the
+ * IOMMU users.
+ */
+ if (!dev->of_node)
+ return 0;
+
+ /*
+ * retrieve the count of IOMMU nodes using phandle size as element size
+ * since #iommu-cells = 0 for OMAP
+ */
+ num_iommus = of_property_count_elems_of_size(dev->of_node, "iommus",
+ sizeof(phandle));
+ if (num_iommus < 0)
+ return 0;
+
+ arch_data = kcalloc(num_iommus + 1, sizeof(*arch_data), GFP_KERNEL);
+ if (!arch_data)
+ return -ENOMEM;
+
+ for (i = 0, tmp = arch_data; i < num_iommus; i++, tmp++) {
+ np = of_parse_phandle(dev->of_node, "iommus", i);
+ if (!np) {
+ kfree(arch_data);
+ return -EINVAL;
+ }
+
+ pdev = of_find_device_by_node(np);
+ if (WARN_ON(!pdev)) {
+ of_node_put(np);
+ kfree(arch_data);
+ return -EINVAL;
+ }
+
+ oiommu = platform_get_drvdata(pdev);
+ if (!oiommu) {
+ of_node_put(np);
+ kfree(arch_data);
+ return -EINVAL;
+ }
+
+ tmp->iommu_dev = oiommu;
+
+ of_node_put(np);
+ }
+
+ /*
+ * use the first IOMMU alone for the sysfs device linking.
+ * TODO: Evaluate if a single iommu_group needs to be
+ * maintained for both IOMMUs
+ */
+ oiommu = arch_data->iommu_dev;
+ ret = iommu_device_link(&oiommu->iommu, dev);
+ if (ret) {
+ kfree(arch_data);
+ return ret;
+ }
+
+ dev->archdata.iommu = arch_data;
+
+ /*
+ * IOMMU group initialization calls into omap_iommu_device_group, which
+ * needs a valid dev->archdata.iommu pointer
+ */
+ group = iommu_group_get_for_dev(dev);
+ if (IS_ERR(group)) {
+ iommu_device_unlink(&oiommu->iommu, dev);
+ dev->archdata.iommu = NULL;
+ kfree(arch_data);
+ return PTR_ERR(group);
+ }
+ iommu_group_put(group);
+
+ return 0;
+}
+
+static void omap_iommu_remove_device(struct device *dev)
+{
+ struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+
+ if (!dev->of_node || !arch_data)
+ return;
+
+ iommu_device_unlink(&arch_data->iommu_dev->iommu, dev);
+ iommu_group_remove_device(dev);
+
+ dev->archdata.iommu = NULL;
+ kfree(arch_data);
+
+}
+
+static struct iommu_group *omap_iommu_device_group(struct device *dev)
+{
+ struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
+ struct iommu_group *group = ERR_PTR(-EINVAL);
+
+ if (arch_data->iommu_dev)
+ group = iommu_group_ref_get(arch_data->iommu_dev->group);
+
+ return group;
+}
+
+static const struct iommu_ops omap_iommu_ops = {
+ .domain_alloc = omap_iommu_domain_alloc,
+ .domain_free = omap_iommu_domain_free,
+ .attach_dev = omap_iommu_attach_dev,
+ .detach_dev = omap_iommu_detach_dev,
+ .map = omap_iommu_map,
+ .unmap = omap_iommu_unmap,
+ .iova_to_phys = omap_iommu_iova_to_phys,
+ .add_device = omap_iommu_add_device,
+ .remove_device = omap_iommu_remove_device,
+ .device_group = omap_iommu_device_group,
+ .pgsize_bitmap = OMAP_IOMMU_PGSIZES,
+};
+
+static int __init omap_iommu_init(void)
+{
+ struct kmem_cache *p;
+ const unsigned long flags = SLAB_HWCACHE_ALIGN;
+ size_t align = 1 << 10; /* L2 pagetable alignement */
+ struct device_node *np;
+ int ret;
+
+ np = of_find_matching_node(NULL, omap_iommu_of_match);
+ if (!np)
+ return 0;
+
+ of_node_put(np);
+
+ p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags,
+ NULL);
+ if (!p)
+ return -ENOMEM;
+ iopte_cachep = p;
+
+ omap_iommu_debugfs_init();
+
+ ret = platform_driver_register(&omap_iommu_driver);
+ if (ret) {
+ pr_err("%s: failed to register driver\n", __func__);
+ goto fail_driver;
+ }
+
+ ret = bus_set_iommu(&platform_bus_type, &omap_iommu_ops);
+ if (ret)
+ goto fail_bus;
+
+ return 0;
+
+fail_bus:
+ platform_driver_unregister(&omap_iommu_driver);
+fail_driver:
+ kmem_cache_destroy(iopte_cachep);
+ return ret;
+}
+subsys_initcall(omap_iommu_init);
+/* must be ready before omap3isp is probed */