linux/drivers/gpu/drm/exynos/exynos_drm_iommu.h
Robin Murphy fade1ec055 iommu/dma: Avoid PCI host bridge windows
With our DMA ops enabled for PCI devices, we should avoid allocating
IOVAs which a host bridge might misinterpret as peer-to-peer DMA and
lead to faults, corruption or other badness. To be safe, punch out holes
for all of the relevant host bridge's windows when initialising a DMA
domain for a PCI device.

CC: Marek Szyprowski <m.szyprowski@samsung.com>
CC: Inki Dae <inki.dae@samsung.com>
Reported-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-16 09:34:22 +01:00

157 lines
3.5 KiB
C

/* exynos_drm_iommu.h
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* Authoer: Inki Dae <inki.dae@samsung.com>
*
* 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; either version 2 of the License, or (at your
* option) any later version.
*/
#ifndef _EXYNOS_DRM_IOMMU_H_
#define _EXYNOS_DRM_IOMMU_H_
#define EXYNOS_DEV_ADDR_START 0x20000000
#define EXYNOS_DEV_ADDR_SIZE 0x40000000
#ifdef CONFIG_DRM_EXYNOS_IOMMU
#if defined(CONFIG_ARM_DMA_USE_IOMMU)
#include <asm/dma-iommu.h>
static inline int __exynos_iommu_create_mapping(struct exynos_drm_private *priv,
unsigned long start, unsigned long size)
{
priv->mapping = arm_iommu_create_mapping(&platform_bus_type, start,
size);
return IS_ERR(priv->mapping);
}
static inline void
__exynos_iommu_release_mapping(struct exynos_drm_private *priv)
{
arm_iommu_release_mapping(priv->mapping);
}
static inline int __exynos_iommu_attach(struct exynos_drm_private *priv,
struct device *dev)
{
if (dev->archdata.mapping)
arm_iommu_detach_device(dev);
return arm_iommu_attach_device(dev, priv->mapping);
}
static inline void __exynos_iommu_detach(struct exynos_drm_private *priv,
struct device *dev)
{
arm_iommu_detach_device(dev);
}
#elif defined(CONFIG_IOMMU_DMA)
#include <linux/dma-iommu.h>
static inline int __exynos_iommu_create_mapping(struct exynos_drm_private *priv,
unsigned long start, unsigned long size)
{
struct iommu_domain *domain;
int ret;
domain = iommu_domain_alloc(priv->dma_dev->bus);
if (!domain)
return -ENOMEM;
ret = iommu_get_dma_cookie(domain);
if (ret)
goto free_domain;
ret = iommu_dma_init_domain(domain, start, size, NULL);
if (ret)
goto put_cookie;
priv->mapping = domain;
return 0;
put_cookie:
iommu_put_dma_cookie(domain);
free_domain:
iommu_domain_free(domain);
return ret;
}
static inline void __exynos_iommu_release_mapping(struct exynos_drm_private *priv)
{
struct iommu_domain *domain = priv->mapping;
iommu_put_dma_cookie(domain);
iommu_domain_free(domain);
priv->mapping = NULL;
}
static inline int __exynos_iommu_attach(struct exynos_drm_private *priv,
struct device *dev)
{
struct iommu_domain *domain = priv->mapping;
return iommu_attach_device(domain, dev);
}
static inline void __exynos_iommu_detach(struct exynos_drm_private *priv,
struct device *dev)
{
struct iommu_domain *domain = priv->mapping;
iommu_detach_device(domain, dev);
}
#else
#error Unsupported architecture and IOMMU/DMA-mapping glue code
#endif
int drm_create_iommu_mapping(struct drm_device *drm_dev);
void drm_release_iommu_mapping(struct drm_device *drm_dev);
int drm_iommu_attach_device(struct drm_device *drm_dev,
struct device *subdrv_dev);
void drm_iommu_detach_device(struct drm_device *dev_dev,
struct device *subdrv_dev);
static inline bool is_drm_iommu_supported(struct drm_device *drm_dev)
{
struct exynos_drm_private *priv = drm_dev->dev_private;
return priv->mapping ? true : false;
}
#else
static inline int drm_create_iommu_mapping(struct drm_device *drm_dev)
{
return 0;
}
static inline void drm_release_iommu_mapping(struct drm_device *drm_dev)
{
}
static inline int drm_iommu_attach_device(struct drm_device *drm_dev,
struct device *subdrv_dev)
{
return 0;
}
static inline void drm_iommu_detach_device(struct drm_device *drm_dev,
struct device *subdrv_dev)
{
}
static inline bool is_drm_iommu_supported(struct drm_device *drm_dev)
{
return false;
}
#endif
#endif