LXR linux/drivers/gpu/drm/msm/msm

   1/*
   2 * Copyright (C) 2013 Red Hat
   3 * Author: Rob Clark <robdclark@gmail.com>
   4 *
   5 * This program is free software; you can redistribute it and/or modify it
   6 * under the terms of the GNU General Public License version 2 as published by
   7 * the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it will be useful, but WITHOUT
  10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 * more details.
  13 *
  14 * You should have received a copy of the GNU General Public License along with
  15 * this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18#include "msm_drv.h"
  19#include "msm_mmu.h"
  20
  21struct msm_iommu {
  22        struct msm_mmu base;
  23        struct iommu_domain *domain;
  24};
  25#define to_msm_iommu(x) container_of(x, struct msm_iommu, base)
  26
  27static int msm_fault_handler(struct iommu_domain *iommu, struct device *dev,
  28                unsigned long iova, int flags, void *arg)
  29{
  30        pr_warn_ratelimited("*** fault: iova=%08lx, flags=%d\n", iova, flags);
  31        return 0;
  32}
  33
  34static int msm_iommu_attach(struct msm_mmu *mmu, const char * const *names,
  35                            int cnt)
  36{
  37        struct msm_iommu *iommu = to_msm_iommu(mmu);
  38        return iommu_attach_device(iommu->domain, mmu->dev);
  39}
  40
  41static void msm_iommu_detach(struct msm_mmu *mmu, const char * const *names,
  42                             int cnt)
  43{
  44        struct msm_iommu *iommu = to_msm_iommu(mmu);
  45        iommu_detach_device(iommu->domain, mmu->dev);
  46}
  47
  48static int msm_iommu_map(struct msm_mmu *mmu, uint32_t iova,
  49                struct sg_table *sgt, unsigned len, int prot)
  50{
  51        struct msm_iommu *iommu = to_msm_iommu(mmu);
  52        struct iommu_domain *domain = iommu->domain;
  53        struct scatterlist *sg;
  54        unsigned int da = iova;
  55        unsigned int i, j;
  56        int ret;
  57
  58        if (!domain || !sgt)
  59                return -EINVAL;
  60
  61        for_each_sg(sgt->sgl, sg, sgt->nents, i) {
  62                u32 pa = sg_phys(sg) - sg->offset;
  63                size_t bytes = sg->length + sg->offset;
  64
  65                VERB("map[%d]: %08x %08x(%zx)", i, iova, pa, bytes);
  66
  67                ret = iommu_map(domain, da, pa, bytes, prot);
  68                if (ret)
  69                        goto fail;
  70
  71                da += bytes;
  72        }
  73
  74        return 0;
  75
  76fail:
  77        da = iova;
  78
  79        for_each_sg(sgt->sgl, sg, i, j) {
  80                size_t bytes = sg->length + sg->offset;
  81                iommu_unmap(domain, da, bytes);
  82                da += bytes;
  83        }
  84        return ret;
  85}
  86
  87static int msm_iommu_unmap(struct msm_mmu *mmu, uint32_t iova,
  88                struct sg_table *sgt, unsigned len)
  89{
  90        struct msm_iommu *iommu = to_msm_iommu(mmu);
  91        struct iommu_domain *domain = iommu->domain;
  92        struct scatterlist *sg;
  93        unsigned int da = iova;
  94        int i;
  95
  96        for_each_sg(sgt->sgl, sg, sgt->nents, i) {
  97                size_t bytes = sg->length + sg->offset;
  98                size_t unmapped;
  99
 100                unmapped = iommu_unmap(domain, da, bytes);
 101                if (unmapped < bytes)
 102                        return unmapped;
 103
 104                VERB("unmap[%d]: %08x(%zx)", i, iova, bytes);
 105
 106                BUG_ON(!PAGE_ALIGNED(bytes));
 107
 108                da += bytes;
 109        }
 110
 111        return 0;
 112}
 113
 114static void msm_iommu_destroy(struct msm_mmu *mmu)
 115{
 116        struct msm_iommu *iommu = to_msm_iommu(mmu);
 117        iommu_domain_free(iommu->domain);
 118        kfree(iommu);
 119}
 120
 121static const struct msm_mmu_funcs funcs = {
 122                .attach = msm_iommu_attach,
 123                .detach = msm_iommu_detach,
 124                .map = msm_iommu_map,
 125                .unmap = msm_iommu_unmap,
 126                .destroy = msm_iommu_destroy,
 127};
 128
 129struct msm_mmu *msm_iommu_new(struct device *dev, struct iommu_domain *domain)
 130{
 131        struct msm_iommu *iommu;
 132
 133        iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
 134        if (!iommu)
 135                return ERR_PTR(-ENOMEM);
 136
 137        iommu->domain = domain;
 138        msm_mmu_init(&iommu->base, dev, &funcs);
 139        iommu_set_fault_handler(domain, msm_fault_handler, dev);
 140
 141        return &iommu->base;
 142}
 143