17.06.2019 16:31, Hans Verkuil пишет:
> On 6/2/19 11:37 PM, Dmitry Osipenko wrote:
>> All Tegra's could provide memory isolation for the video decoder
>> hardware using IOMMU, it is also required for Tegra30+ in order
>> to handle sparse dmabuf's which GPU exports in a default kernel
>> configuration.
>>
>> Inspired-by: Thierry Reding <thierry.reding@xxxxxxxxx>
>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>> ---
>> drivers/staging/media/tegra-vde/Kconfig | 1 +
>> drivers/staging/media/tegra-vde/Makefile | 1 +
>> drivers/staging/media/tegra-vde/iommu.c | 148 ++++++++++++++
>> drivers/staging/media/tegra-vde/trace.h | 1 +
>> .../media/tegra-vde/{tegra-vde.c => vde.c} | 188 +++++++++---------
>> drivers/staging/media/tegra-vde/vde.h | 89 +++++++++
>> 6 files changed, 335 insertions(+), 93 deletions(-)
>> create mode 100644 drivers/staging/media/tegra-vde/iommu.c
>> rename drivers/staging/media/tegra-vde/{tegra-vde.c => vde.c} (91%)
>> create mode 100644 drivers/staging/media/tegra-vde/vde.h
>>
>> diff --git a/drivers/staging/media/tegra-vde/Kconfig b/drivers/staging/media/tegra-vde/Kconfig
>> index ff8e846cd15d..2e7f644ae591 100644
>> --- a/drivers/staging/media/tegra-vde/Kconfig
>> +++ b/drivers/staging/media/tegra-vde/Kconfig
>> @@ -3,6 +3,7 @@ config TEGRA_VDE
>> tristate "NVIDIA Tegra Video Decoder Engine driver"
>> depends on ARCH_TEGRA || COMPILE_TEST
>> select DMA_SHARED_BUFFER
>> + select IOMMU_IOVA if IOMMU_SUPPORT
>> select SRAM
>> help
>> Say Y here to enable support for the NVIDIA Tegra video decoder
>> diff --git a/drivers/staging/media/tegra-vde/Makefile b/drivers/staging/media/tegra-vde/Makefile
>> index 7f9020e634f3..c11867e28233 100644
>> --- a/drivers/staging/media/tegra-vde/Makefile
>> +++ b/drivers/staging/media/tegra-vde/Makefile
>> @@ -1,2 +1,3 @@
>> # SPDX-License-Identifier: GPL-2.0
>> +tegra-vde-y := vde.o iommu.o
>> obj-$(CONFIG_TEGRA_VDE) += tegra-vde.o
>> diff --git a/drivers/staging/media/tegra-vde/iommu.c b/drivers/staging/media/tegra-vde/iommu.c
>> new file mode 100644
>> index 000000000000..295c3d7cccd3
>> --- /dev/null
>> +++ b/drivers/staging/media/tegra-vde/iommu.c
>> @@ -0,0 +1,148 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * NVIDIA Tegra Video decoder driver
>> + *
>> + * Copyright (C) 2016-2019 GRATE-DRIVER project
>> + */
>> +
>> +#include <linux/iommu.h>
>> +#include <linux/iova.h>
>> +#include <linux/kernel.h>
>> +#include <linux/platform_device.h>
>> +
>> +#if IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)
>> +#include <asm/dma-iommu.h>
>> +#endif
>> +
>> +#include "vde.h"
>> +
>> +int tegra_vde_iommu_map(struct tegra_vde *vde,
>> + struct sg_table *sgt,
>> + struct iova **iovap,
>> + dma_addr_t *addrp,
>> + size_t size)
>> +{
>> + struct iova *iova;
>> + unsigned long shift;
>> + unsigned long end;
>> + dma_addr_t addr;
>> +
>> + end = vde->domain->geometry.aperture_end;
>> + size = iova_align(&vde->iova, size);
>> + shift = iova_shift(&vde->iova);
>> +
>> + iova = alloc_iova(&vde->iova, size >> shift, end >> shift, true);
>> + if (!iova)
>> + return -ENOMEM;
>> +
>> + addr = iova_dma_addr(&vde->iova, iova);
>> +
>> + size = iommu_map_sg(vde->domain, addr, sgt->sgl, sgt->nents,
>> + IOMMU_READ | IOMMU_WRITE);
>> + if (!size) {
>> + __free_iova(&vde->iova, iova);
>> + return -ENXIO;
>> + }
>> +
>> + *iovap = iova;
>> + *addrp = addr;
>> +
>> + return 0;
>> +}
>> +
>> +void tegra_vde_iommu_unmap(struct tegra_vde *vde, struct iova *iova)
>> +{
>> + unsigned long shift = iova_shift(&vde->iova);
>> + unsigned long size = iova_size(iova) << shift;
>> + dma_addr_t addr = iova_dma_addr(&vde->iova, iova);
>> +
>> + iommu_unmap(vde->domain, addr, size);
>> + __free_iova(&vde->iova, iova);
>> +}
>> +
>> +int tegra_vde_iommu_init(struct tegra_vde *vde)
>> +{
>> + struct iova *iova;
>> + unsigned long order;
>> + unsigned long shift;
>> + int err;
>> +
>> + vde->group = iommu_group_get(vde->miscdev.parent);
>> + if (!vde->group)
>> + return 0;
>> +
>> +#if IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)
>> + if (dev->archdata.mapping) {
>
> 'dev' doesn't exist, so this fails to compile!
Oh, indeed! I actually didn't even try to compile with CONFIG_ARM_DMA_USE_IOMMU. Will
fix it in v2, thanks!
