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path: root/drivers/iommu/shmobile-iommu.c
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Diffstat (limited to 'drivers/iommu/shmobile-iommu.c')
-rw-r--r--drivers/iommu/shmobile-iommu.c395
1 files changed, 395 insertions, 0 deletions
diff --git a/drivers/iommu/shmobile-iommu.c b/drivers/iommu/shmobile-iommu.c
new file mode 100644
index 000000000000..b6e8b57cf0a8
--- /dev/null
+++ b/drivers/iommu/shmobile-iommu.c
@@ -0,0 +1,395 @@
+/*
+ * IOMMU for IPMMU/IPMMUI
+ * Copyright (C) 2012 Hideki EIRAKU
+ *
+ * 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/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/iommu.h>
+#include <linux/platform_device.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <asm/dma-iommu.h>
+#include "shmobile-ipmmu.h"
+
+#define L1_SIZE CONFIG_SHMOBILE_IOMMU_L1SIZE
+#define L1_LEN (L1_SIZE / 4)
+#define L1_ALIGN L1_SIZE
+#define L2_SIZE SZ_1K
+#define L2_LEN (L2_SIZE / 4)
+#define L2_ALIGN L2_SIZE
+
+struct shmobile_iommu_domain_pgtable {
+ uint32_t *pgtable;
+ dma_addr_t handle;
+};
+
+struct shmobile_iommu_archdata {
+ struct list_head attached_list;
+ struct dma_iommu_mapping *iommu_mapping;
+ spinlock_t attach_lock;
+ struct shmobile_iommu_domain *attached;
+ int num_attached_devices;
+ struct shmobile_ipmmu *ipmmu;
+};
+
+struct shmobile_iommu_domain {
+ struct shmobile_iommu_domain_pgtable l1, l2[L1_LEN];
+ spinlock_t map_lock;
+ spinlock_t attached_list_lock;
+ struct list_head attached_list;
+};
+
+static struct shmobile_iommu_archdata *ipmmu_archdata;
+static struct kmem_cache *l1cache, *l2cache;
+
+static int pgtable_alloc(struct shmobile_iommu_domain_pgtable *pgtable,
+ struct kmem_cache *cache, size_t size)
+{
+ pgtable->pgtable = kmem_cache_zalloc(cache, GFP_ATOMIC);
+ if (!pgtable->pgtable)
+ return -ENOMEM;
+ pgtable->handle = dma_map_single(NULL, pgtable->pgtable, size,
+ DMA_TO_DEVICE);
+ return 0;
+}
+
+static void pgtable_free(struct shmobile_iommu_domain_pgtable *pgtable,
+ struct kmem_cache *cache, size_t size)
+{
+ dma_unmap_single(NULL, pgtable->handle, size, DMA_TO_DEVICE);
+ kmem_cache_free(cache, pgtable->pgtable);
+}
+
+static uint32_t pgtable_read(struct shmobile_iommu_domain_pgtable *pgtable,
+ unsigned int index)
+{
+ return pgtable->pgtable[index];
+}
+
+static void pgtable_write(struct shmobile_iommu_domain_pgtable *pgtable,
+ unsigned int index, unsigned int count, uint32_t val)
+{
+ unsigned int i;
+
+ for (i = 0; i < count; i++)
+ pgtable->pgtable[index + i] = val;
+ dma_sync_single_for_device(NULL, pgtable->handle + index * sizeof(val),
+ sizeof(val) * count, DMA_TO_DEVICE);
+}
+
+static int shmobile_iommu_domain_init(struct iommu_domain *domain)
+{
+ struct shmobile_iommu_domain *sh_domain;
+ int i, ret;
+
+ sh_domain = kmalloc(sizeof(*sh_domain), GFP_KERNEL);
+ if (!sh_domain)
+ return -ENOMEM;
+ ret = pgtable_alloc(&sh_domain->l1, l1cache, L1_SIZE);
+ if (ret < 0) {
+ kfree(sh_domain);
+ return ret;
+ }
+ for (i = 0; i < L1_LEN; i++)
+ sh_domain->l2[i].pgtable = NULL;
+ spin_lock_init(&sh_domain->map_lock);
+ spin_lock_init(&sh_domain->attached_list_lock);
+ INIT_LIST_HEAD(&sh_domain->attached_list);
+ domain->priv = sh_domain;
+ return 0;
+}
+
+static void shmobile_iommu_domain_destroy(struct iommu_domain *domain)
+{
+ struct shmobile_iommu_domain *sh_domain = domain->priv;
+ int i;
+
+ for (i = 0; i < L1_LEN; i++) {
+ if (sh_domain->l2[i].pgtable)
+ pgtable_free(&sh_domain->l2[i], l2cache, L2_SIZE);
+ }
+ pgtable_free(&sh_domain->l1, l1cache, L1_SIZE);
+ kfree(sh_domain);
+ domain->priv = NULL;
+}
+
+static int shmobile_iommu_attach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct shmobile_iommu_archdata *archdata = dev->archdata.iommu;
+ struct shmobile_iommu_domain *sh_domain = domain->priv;
+ int ret = -EBUSY;
+
+ if (!archdata)
+ return -ENODEV;
+ spin_lock(&sh_domain->attached_list_lock);
+ spin_lock(&archdata->attach_lock);
+ if (archdata->attached != sh_domain) {
+ if (archdata->attached)
+ goto err;
+ ipmmu_tlb_set(archdata->ipmmu, sh_domain->l1.handle, L1_SIZE,
+ 0);
+ ipmmu_tlb_flush(archdata->ipmmu);
+ archdata->attached = sh_domain;
+ archdata->num_attached_devices = 0;
+ list_add(&archdata->attached_list, &sh_domain->attached_list);
+ }
+ archdata->num_attached_devices++;
+ ret = 0;
+err:
+ spin_unlock(&archdata->attach_lock);
+ spin_unlock(&sh_domain->attached_list_lock);
+ return ret;
+}
+
+static void shmobile_iommu_detach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ struct shmobile_iommu_archdata *archdata = dev->archdata.iommu;
+ struct shmobile_iommu_domain *sh_domain = domain->priv;
+
+ if (!archdata)
+ return;
+ spin_lock(&sh_domain->attached_list_lock);
+ spin_lock(&archdata->attach_lock);
+ archdata->num_attached_devices--;
+ if (!archdata->num_attached_devices) {
+ ipmmu_tlb_set(archdata->ipmmu, 0, 0, 0);
+ ipmmu_tlb_flush(archdata->ipmmu);
+ archdata->attached = NULL;
+ list_del(&archdata->attached_list);
+ }
+ spin_unlock(&archdata->attach_lock);
+ spin_unlock(&sh_domain->attached_list_lock);
+}
+
+static void domain_tlb_flush(struct shmobile_iommu_domain *sh_domain)
+{
+ struct shmobile_iommu_archdata *archdata;
+
+ spin_lock(&sh_domain->attached_list_lock);
+ list_for_each_entry(archdata, &sh_domain->attached_list, attached_list)
+ ipmmu_tlb_flush(archdata->ipmmu);
+ spin_unlock(&sh_domain->attached_list_lock);
+}
+
+static int l2alloc(struct shmobile_iommu_domain *sh_domain,
+ unsigned int l1index)
+{
+ int ret;
+
+ if (!sh_domain->l2[l1index].pgtable) {
+ ret = pgtable_alloc(&sh_domain->l2[l1index], l2cache, L2_SIZE);
+ if (ret < 0)
+ return ret;
+ }
+ pgtable_write(&sh_domain->l1, l1index, 1,
+ sh_domain->l2[l1index].handle | 0x1);
+ return 0;
+}
+
+static void l2realfree(struct shmobile_iommu_domain_pgtable *l2)
+{
+ if (l2->pgtable)
+ pgtable_free(l2, l2cache, L2_SIZE);
+}
+
+static void l2free(struct shmobile_iommu_domain *sh_domain,
+ unsigned int l1index,
+ struct shmobile_iommu_domain_pgtable *l2)
+{
+ pgtable_write(&sh_domain->l1, l1index, 1, 0);
+ if (sh_domain->l2[l1index].pgtable) {
+ *l2 = sh_domain->l2[l1index];
+ sh_domain->l2[l1index].pgtable = NULL;
+ }
+}
+
+static int shmobile_iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ struct shmobile_iommu_domain_pgtable l2 = { .pgtable = NULL };
+ struct shmobile_iommu_domain *sh_domain = domain->priv;
+ unsigned int l1index, l2index;
+ int ret;
+
+ l1index = iova >> 20;
+ switch (size) {
+ case SZ_4K:
+ l2index = (iova >> 12) & 0xff;
+ spin_lock(&sh_domain->map_lock);
+ ret = l2alloc(sh_domain, l1index);
+ if (!ret)
+ pgtable_write(&sh_domain->l2[l1index], l2index, 1,
+ paddr | 0xff2);
+ spin_unlock(&sh_domain->map_lock);
+ break;
+ case SZ_64K:
+ l2index = (iova >> 12) & 0xf0;
+ spin_lock(&sh_domain->map_lock);
+ ret = l2alloc(sh_domain, l1index);
+ if (!ret)
+ pgtable_write(&sh_domain->l2[l1index], l2index, 0x10,
+ paddr | 0xff1);
+ spin_unlock(&sh_domain->map_lock);
+ break;
+ case SZ_1M:
+ spin_lock(&sh_domain->map_lock);
+ l2free(sh_domain, l1index, &l2);
+ pgtable_write(&sh_domain->l1, l1index, 1, paddr | 0xc02);
+ spin_unlock(&sh_domain->map_lock);
+ ret = 0;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ if (!ret)
+ domain_tlb_flush(sh_domain);
+ l2realfree(&l2);
+ return ret;
+}
+
+static size_t shmobile_iommu_unmap(struct iommu_domain *domain,
+ unsigned long iova, size_t size)
+{
+ struct shmobile_iommu_domain_pgtable l2 = { .pgtable = NULL };
+ struct shmobile_iommu_domain *sh_domain = domain->priv;
+ unsigned int l1index, l2index;
+ uint32_t l2entry = 0;
+ size_t ret = 0;
+
+ l1index = iova >> 20;
+ if (!(iova & 0xfffff) && size >= SZ_1M) {
+ spin_lock(&sh_domain->map_lock);
+ l2free(sh_domain, l1index, &l2);
+ spin_unlock(&sh_domain->map_lock);
+ ret = SZ_1M;
+ goto done;
+ }
+ l2index = (iova >> 12) & 0xff;
+ spin_lock(&sh_domain->map_lock);
+ if (sh_domain->l2[l1index].pgtable)
+ l2entry = pgtable_read(&sh_domain->l2[l1index], l2index);
+ switch (l2entry & 3) {
+ case 1:
+ if (l2index & 0xf)
+ break;
+ pgtable_write(&sh_domain->l2[l1index], l2index, 0x10, 0);
+ ret = SZ_64K;
+ break;
+ case 2:
+ pgtable_write(&sh_domain->l2[l1index], l2index, 1, 0);
+ ret = SZ_4K;
+ break;
+ }
+ spin_unlock(&sh_domain->map_lock);
+done:
+ if (ret)
+ domain_tlb_flush(sh_domain);
+ l2realfree(&l2);
+ return ret;
+}
+
+static phys_addr_t shmobile_iommu_iova_to_phys(struct iommu_domain *domain,
+ unsigned long iova)
+{
+ struct shmobile_iommu_domain *sh_domain = domain->priv;
+ uint32_t l1entry = 0, l2entry = 0;
+ unsigned int l1index, l2index;
+
+ l1index = iova >> 20;
+ l2index = (iova >> 12) & 0xff;
+ spin_lock(&sh_domain->map_lock);
+ if (sh_domain->l2[l1index].pgtable)
+ l2entry = pgtable_read(&sh_domain->l2[l1index], l2index);
+ else
+ l1entry = pgtable_read(&sh_domain->l1, l1index);
+ spin_unlock(&sh_domain->map_lock);
+ switch (l2entry & 3) {
+ case 1:
+ return (l2entry & ~0xffff) | (iova & 0xffff);
+ case 2:
+ return (l2entry & ~0xfff) | (iova & 0xfff);
+ default:
+ if ((l1entry & 3) == 2)
+ return (l1entry & ~0xfffff) | (iova & 0xfffff);
+ return 0;
+ }
+}
+
+static int find_dev_name(struct shmobile_ipmmu *ipmmu, const char *dev_name)
+{
+ unsigned int i, n = ipmmu->num_dev_names;
+
+ for (i = 0; i < n; i++) {
+ if (strcmp(ipmmu->dev_names[i], dev_name) == 0)
+ return 1;
+ }
+ return 0;
+}
+
+static int shmobile_iommu_add_device(struct device *dev)
+{
+ struct shmobile_iommu_archdata *archdata = ipmmu_archdata;
+ struct dma_iommu_mapping *mapping;
+
+ if (!find_dev_name(archdata->ipmmu, dev_name(dev)))
+ return 0;
+ mapping = archdata->iommu_mapping;
+ if (!mapping) {
+ mapping = arm_iommu_create_mapping(&platform_bus_type, 0,
+ L1_LEN << 20, 0);
+ if (IS_ERR(mapping))
+ return PTR_ERR(mapping);
+ archdata->iommu_mapping = mapping;
+ }
+ dev->archdata.iommu = archdata;
+ if (arm_iommu_attach_device(dev, mapping))
+ pr_err("arm_iommu_attach_device failed\n");
+ return 0;
+}
+
+static struct iommu_ops shmobile_iommu_ops = {
+ .domain_init = shmobile_iommu_domain_init,
+ .domain_destroy = shmobile_iommu_domain_destroy,
+ .attach_dev = shmobile_iommu_attach_device,
+ .detach_dev = shmobile_iommu_detach_device,
+ .map = shmobile_iommu_map,
+ .unmap = shmobile_iommu_unmap,
+ .iova_to_phys = shmobile_iommu_iova_to_phys,
+ .add_device = shmobile_iommu_add_device,
+ .pgsize_bitmap = SZ_1M | SZ_64K | SZ_4K,
+};
+
+int ipmmu_iommu_init(struct shmobile_ipmmu *ipmmu)
+{
+ static struct shmobile_iommu_archdata *archdata;
+
+ l1cache = kmem_cache_create("shmobile-iommu-pgtable1", L1_SIZE,
+ L1_ALIGN, SLAB_HWCACHE_ALIGN, NULL);
+ if (!l1cache)
+ return -ENOMEM;
+ l2cache = kmem_cache_create("shmobile-iommu-pgtable2", L2_SIZE,
+ L2_ALIGN, SLAB_HWCACHE_ALIGN, NULL);
+ if (!l2cache) {
+ kmem_cache_destroy(l1cache);
+ return -ENOMEM;
+ }
+ archdata = kmalloc(sizeof(*archdata), GFP_KERNEL);
+ if (!archdata) {
+ kmem_cache_destroy(l1cache);
+ kmem_cache_destroy(l2cache);
+ return -ENOMEM;
+ }
+ spin_lock_init(&archdata->attach_lock);
+ archdata->attached = NULL;
+ archdata->ipmmu = ipmmu;
+ ipmmu_archdata = archdata;
+ bus_set_iommu(&platform_bus_type, &shmobile_iommu_ops);
+ return 0;
+}