+++ /dev/null
-/*
- * omap iommu: simple virtual address space management
- *
- * Copyright (C) 2008-2009 Nokia Corporation
- *
- * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
- *
- * 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/module.h>
-#include <linux/err.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-#include <linux/device.h>
-#include <linux/scatterlist.h>
-#include <linux/iommu.h>
-#include <linux/omap-iommu.h>
-#include <linux/platform_data/iommu-omap.h>
-
-#include <asm/cacheflush.h>
-#include <asm/mach/map.h>
-
-#include "omap-iopgtable.h"
-#include "omap-iommu.h"
-
-/*
- * IOVMF_FLAGS: attribute for iommu virtual memory area(iovma)
- *
- * lower 16 bit is used for h/w and upper 16 bit is for s/w.
- */
-#define IOVMF_SW_SHIFT 16
-
-/*
- * iovma: h/w flags derived from cam and ram attribute
- */
-#define IOVMF_CAM_MASK (~((1 << 10) - 1))
-#define IOVMF_RAM_MASK (~IOVMF_CAM_MASK)
-
-#define IOVMF_PGSZ_MASK (3 << 0)
-#define IOVMF_PGSZ_1M MMU_CAM_PGSZ_1M
-#define IOVMF_PGSZ_64K MMU_CAM_PGSZ_64K
-#define IOVMF_PGSZ_4K MMU_CAM_PGSZ_4K
-#define IOVMF_PGSZ_16M MMU_CAM_PGSZ_16M
-
-#define IOVMF_ENDIAN_MASK (1 << 9)
-#define IOVMF_ENDIAN_BIG MMU_RAM_ENDIAN_BIG
-
-#define IOVMF_ELSZ_MASK (3 << 7)
-#define IOVMF_ELSZ_16 MMU_RAM_ELSZ_16
-#define IOVMF_ELSZ_32 MMU_RAM_ELSZ_32
-#define IOVMF_ELSZ_NONE MMU_RAM_ELSZ_NONE
-
-#define IOVMF_MIXED_MASK (1 << 6)
-#define IOVMF_MIXED MMU_RAM_MIXED
-
-/*
- * iovma: s/w flags, used for mapping and umapping internally.
- */
-#define IOVMF_MMIO (1 << IOVMF_SW_SHIFT)
-#define IOVMF_ALLOC (2 << IOVMF_SW_SHIFT)
-#define IOVMF_ALLOC_MASK (3 << IOVMF_SW_SHIFT)
-
-/* "superpages" is supported just with physically linear pages */
-#define IOVMF_DISCONT (1 << (2 + IOVMF_SW_SHIFT))
-#define IOVMF_LINEAR (2 << (2 + IOVMF_SW_SHIFT))
-#define IOVMF_LINEAR_MASK (3 << (2 + IOVMF_SW_SHIFT))
-
-#define IOVMF_DA_FIXED (1 << (4 + IOVMF_SW_SHIFT))
-
-static struct kmem_cache *iovm_area_cachep;
-
-/* return the offset of the first scatterlist entry in a sg table */
-static unsigned int sgtable_offset(const struct sg_table *sgt)
-{
- if (!sgt || !sgt->nents)
- return 0;
-
- return sgt->sgl->offset;
-}
-
-/* return total bytes of sg buffers */
-static size_t sgtable_len(const struct sg_table *sgt)
-{
- unsigned int i, total = 0;
- struct scatterlist *sg;
-
- if (!sgt)
- return 0;
-
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
- size_t bytes;
-
- bytes = sg->length + sg->offset;
-
- if (!iopgsz_ok(bytes)) {
- pr_err("%s: sg[%d] not iommu pagesize(%u %u)\n",
- __func__, i, bytes, sg->offset);
- return 0;
- }
-
- if (i && sg->offset) {
- pr_err("%s: sg[%d] offset not allowed in internal entries\n",
- __func__, i);
- return 0;
- }
-
- total += bytes;
- }
-
- return total;
-}
-#define sgtable_ok(x) (!!sgtable_len(x))
-
-static unsigned max_alignment(u32 addr)
-{
- int i;
- unsigned pagesize[] = { SZ_16M, SZ_1M, SZ_64K, SZ_4K, };
- for (i = 0; i < ARRAY_SIZE(pagesize) && addr & (pagesize[i] - 1); i++)
- ;
- return (i < ARRAY_SIZE(pagesize)) ? pagesize[i] : 0;
-}
-
-/*
- * calculate the optimal number sg elements from total bytes based on
- * iommu superpages
- */
-static unsigned sgtable_nents(size_t bytes, u32 da, u32 pa)
-{
- unsigned nr_entries = 0, ent_sz;
-
- if (!PAGE_ALIGNED(bytes)) {
- pr_err("%s: wrong size %08x\n", __func__, bytes);
- return 0;
- }
-
- while (bytes) {
- ent_sz = max_alignment(da | pa);
- ent_sz = min_t(unsigned, ent_sz, iopgsz_max(bytes));
- nr_entries++;
- da += ent_sz;
- pa += ent_sz;
- bytes -= ent_sz;
- }
-
- return nr_entries;
-}
-
-/* allocate and initialize sg_table header(a kind of 'superblock') */
-static struct sg_table *sgtable_alloc(const size_t bytes, u32 flags,
- u32 da, u32 pa)
-{
- unsigned int nr_entries;
- int err;
- struct sg_table *sgt;
-
- if (!bytes)
- return ERR_PTR(-EINVAL);
-
- if (!PAGE_ALIGNED(bytes))
- return ERR_PTR(-EINVAL);
-
- if (flags & IOVMF_LINEAR) {
- nr_entries = sgtable_nents(bytes, da, pa);
- if (!nr_entries)
- return ERR_PTR(-EINVAL);
- } else
- nr_entries = bytes / PAGE_SIZE;
-
- sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
- if (!sgt)
- return ERR_PTR(-ENOMEM);
-
- err = sg_alloc_table(sgt, nr_entries, GFP_KERNEL);
- if (err) {
- kfree(sgt);
- return ERR_PTR(err);
- }
-
- pr_debug("%s: sgt:%p(%d entries)\n", __func__, sgt, nr_entries);
-
- return sgt;
-}
-
-/* free sg_table header(a kind of superblock) */
-static void sgtable_free(struct sg_table *sgt)
-{
- if (!sgt)
- return;
-
- sg_free_table(sgt);
- kfree(sgt);
-
- pr_debug("%s: sgt:%p\n", __func__, sgt);
-}
-
-/* map 'sglist' to a contiguous mpu virtual area and return 'va' */
-static void *vmap_sg(const struct sg_table *sgt)
-{
- u32 va;
- size_t total;
- unsigned int i;
- struct scatterlist *sg;
- struct vm_struct *new;
- const struct mem_type *mtype;
-
- mtype = get_mem_type(MT_DEVICE);
- if (!mtype)
- return ERR_PTR(-EINVAL);
-
- total = sgtable_len(sgt);
- if (!total)
- return ERR_PTR(-EINVAL);
-
- new = __get_vm_area(total, VM_IOREMAP, VMALLOC_START, VMALLOC_END);
- if (!new)
- return ERR_PTR(-ENOMEM);
- va = (u32)new->addr;
-
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
- size_t bytes;
- u32 pa;
- int err;
-
- pa = sg_phys(sg) - sg->offset;
- bytes = sg->length + sg->offset;
-
- BUG_ON(bytes != PAGE_SIZE);
-
- err = ioremap_page(va, pa, mtype);
- if (err)
- goto err_out;
-
- va += bytes;
- }
-
- flush_cache_vmap((unsigned long)new->addr,
- (unsigned long)(new->addr + total));
- return new->addr;
-
-err_out:
- WARN_ON(1); /* FIXME: cleanup some mpu mappings */
- vunmap(new->addr);
- return ERR_PTR(-EAGAIN);
-}
-
-static inline void vunmap_sg(const void *va)
-{
- vunmap(va);
-}
-
-static struct iovm_struct *__find_iovm_area(struct omap_iommu *obj,
- const u32 da)
-{
- struct iovm_struct *tmp;
-
- list_for_each_entry(tmp, &obj->mmap, list) {
- if ((da >= tmp->da_start) && (da < tmp->da_end)) {
- size_t len;
-
- len = tmp->da_end - tmp->da_start;
-
- dev_dbg(obj->dev, "%s: %08x-%08x-%08x(%x) %08x\n",
- __func__, tmp->da_start, da, tmp->da_end, len,
- tmp->flags);
-
- return tmp;
- }
- }
-
- return NULL;
-}
-
-/**
- * omap_find_iovm_area - find iovma which includes @da
- * @dev: client device
- * @da: iommu device virtual address
- *
- * Find the existing iovma starting at @da
- */
-struct iovm_struct *omap_find_iovm_area(struct device *dev, u32 da)
-{
- struct omap_iommu *obj = dev_to_omap_iommu(dev);
- struct iovm_struct *area;
-
- mutex_lock(&obj->mmap_lock);
- area = __find_iovm_area(obj, da);
- mutex_unlock(&obj->mmap_lock);
-
- return area;
-}
-EXPORT_SYMBOL_GPL(omap_find_iovm_area);
-
-/*
- * This finds the hole(area) which fits the requested address and len
- * in iovmas mmap, and returns the new allocated iovma.
- */
-static struct iovm_struct *alloc_iovm_area(struct omap_iommu *obj, u32 da,
- size_t bytes, u32 flags)
-{
- struct iovm_struct *new, *tmp;
- u32 start, prev_end, alignment;
-
- if (!obj || !bytes)
- return ERR_PTR(-EINVAL);
-
- start = da;
- alignment = PAGE_SIZE;
-
- if (~flags & IOVMF_DA_FIXED) {
- /* Don't map address 0 */
- start = obj->da_start ? obj->da_start : alignment;
-
- if (flags & IOVMF_LINEAR)
- alignment = iopgsz_max(bytes);
- start = roundup(start, alignment);
- } else if (start < obj->da_start || start > obj->da_end ||
- obj->da_end - start < bytes) {
- return ERR_PTR(-EINVAL);
- }
-
- tmp = NULL;
- if (list_empty(&obj->mmap))
- goto found;
-
- prev_end = 0;
- list_for_each_entry(tmp, &obj->mmap, list) {
-
- if (prev_end > start)
- break;
-
- if (tmp->da_start > start && (tmp->da_start - start) >= bytes)
- goto found;
-
- if (tmp->da_end >= start && ~flags & IOVMF_DA_FIXED)
- start = roundup(tmp->da_end + 1, alignment);
-
- prev_end = tmp->da_end;
- }
-
- if ((start >= prev_end) && (obj->da_end - start >= bytes))
- goto found;
-
- dev_dbg(obj->dev, "%s: no space to fit %08x(%x) flags: %08x\n",
- __func__, da, bytes, flags);
-
- return ERR_PTR(-EINVAL);
-
-found:
- new = kmem_cache_zalloc(iovm_area_cachep, GFP_KERNEL);
- if (!new)
- return ERR_PTR(-ENOMEM);
-
- new->iommu = obj;
- new->da_start = start;
- new->da_end = start + bytes;
- new->flags = flags;
-
- /*
- * keep ascending order of iovmas
- */
- if (tmp)
- list_add_tail(&new->list, &tmp->list);
- else
- list_add(&new->list, &obj->mmap);
-
- dev_dbg(obj->dev, "%s: found %08x-%08x-%08x(%x) %08x\n",
- __func__, new->da_start, start, new->da_end, bytes, flags);
-
- return new;
-}
-
-static void free_iovm_area(struct omap_iommu *obj, struct iovm_struct *area)
-{
- size_t bytes;
-
- BUG_ON(!obj || !area);
-
- bytes = area->da_end - area->da_start;
-
- dev_dbg(obj->dev, "%s: %08x-%08x(%x) %08x\n",
- __func__, area->da_start, area->da_end, bytes, area->flags);
-
- list_del(&area->list);
- kmem_cache_free(iovm_area_cachep, area);
-}
-
-/**
- * omap_da_to_va - convert (d) to (v)
- * @dev: client device
- * @da: iommu device virtual address
- * @va: mpu virtual address
- *
- * Returns mpu virtual addr which corresponds to a given device virtual addr
- */
-void *omap_da_to_va(struct device *dev, u32 da)
-{
- struct omap_iommu *obj = dev_to_omap_iommu(dev);
- void *va = NULL;
- struct iovm_struct *area;
-
- mutex_lock(&obj->mmap_lock);
-
- area = __find_iovm_area(obj, da);
- if (!area) {
- dev_dbg(obj->dev, "%s: no da area(%08x)\n", __func__, da);
- goto out;
- }
- va = area->va;
-out:
- mutex_unlock(&obj->mmap_lock);
-
- return va;
-}
-EXPORT_SYMBOL_GPL(omap_da_to_va);
-
-static void sgtable_fill_vmalloc(struct sg_table *sgt, void *_va)
-{
- unsigned int i;
- struct scatterlist *sg;
- void *va = _va;
- void *va_end;
-
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
- struct page *pg;
- const size_t bytes = PAGE_SIZE;
-
- /*
- * iommu 'superpage' isn't supported with 'omap_iommu_vmalloc()'
- */
- pg = vmalloc_to_page(va);
- BUG_ON(!pg);
- sg_set_page(sg, pg, bytes, 0);
-
- va += bytes;
- }
-
- va_end = _va + PAGE_SIZE * i;
-}
-
-static inline void sgtable_drain_vmalloc(struct sg_table *sgt)
-{
- /*
- * Actually this is not necessary at all, just exists for
- * consistency of the code readability.
- */
- BUG_ON(!sgt);
-}
-
-/* create 'da' <-> 'pa' mapping from 'sgt' */
-static int map_iovm_area(struct iommu_domain *domain, struct iovm_struct *new,
- const struct sg_table *sgt, u32 flags)
-{
- int err;
- unsigned int i, j;
- struct scatterlist *sg;
- u32 da = new->da_start;
-
- if (!domain || !sgt)
- return -EINVAL;
-
- BUG_ON(!sgtable_ok(sgt));
-
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
- u32 pa;
- size_t bytes;
-
- pa = sg_phys(sg) - sg->offset;
- bytes = sg->length + sg->offset;
-
- flags &= ~IOVMF_PGSZ_MASK;
-
- if (bytes_to_iopgsz(bytes) < 0)
- goto err_out;
-
- pr_debug("%s: [%d] %08x %08x(%x)\n", __func__,
- i, da, pa, bytes);
-
- err = iommu_map(domain, da, pa, bytes, flags);
- if (err)
- goto err_out;
-
- da += bytes;
- }
- return 0;
-
-err_out:
- da = new->da_start;
-
- for_each_sg(sgt->sgl, sg, i, j) {
- size_t bytes;
-
- bytes = sg->length + sg->offset;
-
- /* ignore failures.. we're already handling one */
- iommu_unmap(domain, da, bytes);
-
- da += bytes;
- }
- return err;
-}
-
-/* release 'da' <-> 'pa' mapping */
-static void unmap_iovm_area(struct iommu_domain *domain, struct omap_iommu *obj,
- struct iovm_struct *area)
-{
- u32 start;
- size_t total = area->da_end - area->da_start;
- const struct sg_table *sgt = area->sgt;
- struct scatterlist *sg;
- int i;
- size_t unmapped;
-
- BUG_ON(!sgtable_ok(sgt));
- BUG_ON((!total) || !PAGE_ALIGNED(total));
-
- start = area->da_start;
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
- size_t bytes;
-
- bytes = sg->length + sg->offset;
-
- unmapped = iommu_unmap(domain, start, bytes);
- if (unmapped < bytes)
- break;
-
- dev_dbg(obj->dev, "%s: unmap %08x(%x) %08x\n",
- __func__, start, bytes, area->flags);
-
- BUG_ON(!PAGE_ALIGNED(bytes));
-
- total -= bytes;
- start += bytes;
- }
- BUG_ON(total);
-}
-
-/* template function for all unmapping */
-static struct sg_table *unmap_vm_area(struct iommu_domain *domain,
- struct omap_iommu *obj, const u32 da,
- void (*fn)(const void *), u32 flags)
-{
- struct sg_table *sgt = NULL;
- struct iovm_struct *area;
-
- if (!PAGE_ALIGNED(da)) {
- dev_err(obj->dev, "%s: alignment err(%08x)\n", __func__, da);
- return NULL;
- }
-
- mutex_lock(&obj->mmap_lock);
-
- area = __find_iovm_area(obj, da);
- if (!area) {
- dev_dbg(obj->dev, "%s: no da area(%08x)\n", __func__, da);
- goto out;
- }
-
- if ((area->flags & flags) != flags) {
- dev_err(obj->dev, "%s: wrong flags(%08x)\n", __func__,
- area->flags);
- goto out;
- }
- sgt = (struct sg_table *)area->sgt;
-
- unmap_iovm_area(domain, obj, area);
-
- fn(area->va);
-
- dev_dbg(obj->dev, "%s: %08x-%08x-%08x(%x) %08x\n", __func__,
- area->da_start, da, area->da_end,
- area->da_end - area->da_start, area->flags);
-
- free_iovm_area(obj, area);
-out:
- mutex_unlock(&obj->mmap_lock);
-
- return sgt;
-}
-
-static u32 map_iommu_region(struct iommu_domain *domain, struct omap_iommu *obj,
- u32 da, const struct sg_table *sgt, void *va,
- size_t bytes, u32 flags)
-{
- int err = -ENOMEM;
- struct iovm_struct *new;
-
- mutex_lock(&obj->mmap_lock);
-
- new = alloc_iovm_area(obj, da, bytes, flags);
- if (IS_ERR(new)) {
- err = PTR_ERR(new);
- goto err_alloc_iovma;
- }
- new->va = va;
- new->sgt = sgt;
-
- if (map_iovm_area(domain, new, sgt, new->flags))
- goto err_map;
-
- mutex_unlock(&obj->mmap_lock);
-
- dev_dbg(obj->dev, "%s: da:%08x(%x) flags:%08x va:%p\n",
- __func__, new->da_start, bytes, new->flags, va);
-
- return new->da_start;
-
-err_map:
- free_iovm_area(obj, new);
-err_alloc_iovma:
- mutex_unlock(&obj->mmap_lock);
- return err;
-}
-
-static inline u32
-__iommu_vmap(struct iommu_domain *domain, struct omap_iommu *obj,
- u32 da, const struct sg_table *sgt,
- void *va, size_t bytes, u32 flags)
-{
- return map_iommu_region(domain, obj, da, sgt, va, bytes, flags);
-}
-
-/**
- * omap_iommu_vmap - (d)-(p)-(v) address mapper
- * @domain: iommu domain
- * @dev: client device
- * @sgt: address of scatter gather table
- * @flags: iovma and page property
- *
- * Creates 1-n-1 mapping with given @sgt and returns @da.
- * All @sgt element must be io page size aligned.
- */
-u32 omap_iommu_vmap(struct iommu_domain *domain, struct device *dev, u32 da,
- const struct sg_table *sgt, u32 flags)
-{
- struct omap_iommu *obj = dev_to_omap_iommu(dev);
- size_t bytes;
- void *va = NULL;
-
- if (!obj || !obj->dev || !sgt)
- return -EINVAL;
-
- bytes = sgtable_len(sgt);
- if (!bytes)
- return -EINVAL;
- bytes = PAGE_ALIGN(bytes);
-
- if (flags & IOVMF_MMIO) {
- va = vmap_sg(sgt);
- if (IS_ERR(va))
- return PTR_ERR(va);
- }
-
- flags |= IOVMF_DISCONT;
- flags |= IOVMF_MMIO;
-
- da = __iommu_vmap(domain, obj, da, sgt, va, bytes, flags);
- if (IS_ERR_VALUE(da))
- vunmap_sg(va);
-
- return da + sgtable_offset(sgt);
-}
-EXPORT_SYMBOL_GPL(omap_iommu_vmap);
-
-/**
- * omap_iommu_vunmap - release virtual mapping obtained by 'omap_iommu_vmap()'
- * @domain: iommu domain
- * @dev: client device
- * @da: iommu device virtual address
- *
- * Free the iommu virtually contiguous memory area starting at
- * @da, which was returned by 'omap_iommu_vmap()'.
- */
-struct sg_table *
-omap_iommu_vunmap(struct iommu_domain *domain, struct device *dev, u32 da)
-{
- struct omap_iommu *obj = dev_to_omap_iommu(dev);
- struct sg_table *sgt;
- /*
- * 'sgt' is allocated before 'omap_iommu_vmalloc()' is called.
- * Just returns 'sgt' to the caller to free
- */
- da &= PAGE_MASK;
- sgt = unmap_vm_area(domain, obj, da, vunmap_sg,
- IOVMF_DISCONT | IOVMF_MMIO);
- if (!sgt)
- dev_dbg(obj->dev, "%s: No sgt\n", __func__);
- return sgt;
-}
-EXPORT_SYMBOL_GPL(omap_iommu_vunmap);
-
-/**
- * omap_iommu_vmalloc - (d)-(p)-(v) address allocator and mapper
- * @dev: client device
- * @da: contiguous iommu virtual memory
- * @bytes: allocation size
- * @flags: iovma and page property
- *
- * Allocate @bytes linearly and creates 1-n-1 mapping and returns
- * @da again, which might be adjusted if 'IOVMF_DA_FIXED' is not set.
- */
-u32
-omap_iommu_vmalloc(struct iommu_domain *domain, struct device *dev, u32 da,
- size_t bytes, u32 flags)
-{
- struct omap_iommu *obj = dev_to_omap_iommu(dev);
- void *va;
- struct sg_table *sgt;
-
- if (!obj || !obj->dev || !bytes)
- return -EINVAL;
-
- bytes = PAGE_ALIGN(bytes);
-
- va = vmalloc(bytes);
- if (!va)
- return -ENOMEM;
-
- flags |= IOVMF_DISCONT;
- flags |= IOVMF_ALLOC;
-
- sgt = sgtable_alloc(bytes, flags, da, 0);
- if (IS_ERR(sgt)) {
- da = PTR_ERR(sgt);
- goto err_sgt_alloc;
- }
- sgtable_fill_vmalloc(sgt, va);
-
- da = __iommu_vmap(domain, obj, da, sgt, va, bytes, flags);
- if (IS_ERR_VALUE(da))
- goto err_iommu_vmap;
-
- return da;
-
-err_iommu_vmap:
- sgtable_drain_vmalloc(sgt);
- sgtable_free(sgt);
-err_sgt_alloc:
- vfree(va);
- return da;
-}
-EXPORT_SYMBOL_GPL(omap_iommu_vmalloc);
-
-/**
- * omap_iommu_vfree - release memory allocated by 'omap_iommu_vmalloc()'
- * @dev: client device
- * @da: iommu device virtual address
- *
- * Frees the iommu virtually continuous memory area starting at
- * @da, as obtained from 'omap_iommu_vmalloc()'.
- */
-void omap_iommu_vfree(struct iommu_domain *domain, struct device *dev,
- const u32 da)
-{
- struct omap_iommu *obj = dev_to_omap_iommu(dev);
- struct sg_table *sgt;
-
- sgt = unmap_vm_area(domain, obj, da, vfree,
- IOVMF_DISCONT | IOVMF_ALLOC);
- if (!sgt)
- dev_dbg(obj->dev, "%s: No sgt\n", __func__);
- sgtable_free(sgt);
-}
-EXPORT_SYMBOL_GPL(omap_iommu_vfree);
-
-static int __init iovmm_init(void)
-{
- const unsigned long flags = SLAB_HWCACHE_ALIGN;
- struct kmem_cache *p;
-
- p = kmem_cache_create("iovm_area_cache", sizeof(struct iovm_struct), 0,
- flags, NULL);
- if (!p)
- return -ENOMEM;
- iovm_area_cachep = p;
-
- return 0;
-}
-module_init(iovmm_init);
-
-static void __exit iovmm_exit(void)
-{
- kmem_cache_destroy(iovm_area_cachep);
-}
-module_exit(iovmm_exit);
-
-MODULE_DESCRIPTION("omap iommu: simple virtual address space management");
-MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>");
-MODULE_LICENSE("GPL v2");
projects / cascardo / linux.git / commitdiff