[PATCH v1 3/4] staging: media: tegra-vde: Add IOMMU support

From: Dmitry Osipenko
Date: Sun Jun 02 2019 - 17:48:39 EST

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) {
+ struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+
+ arm_iommu_detach_device(dev);
+ arm_iommu_release_mapping(mapping);
+ }
+#endif
+ vde->domain = iommu_domain_alloc(&platform_bus_type);
+ if (!vde->domain) {
+ err = -ENOMEM;
+ goto put_group;
+ }
+
+ err = iova_cache_get();
+ if (err)
+ goto free_domain;
+
+ order = __ffs(vde->domain->pgsize_bitmap);
+ init_iova_domain(&vde->iova, 1UL << order, 0);
+
+ err = iommu_attach_group(vde->domain, vde->group);
+ if (err)
+ goto put_iova;
+
+ /*
+ * We're using some static addresses that are not accessible by VDE
+ * to trap invalid memory accesses.
+ */
+ shift = iova_shift(&vde->iova);
+ iova = reserve_iova(&vde->iova, 0x60000000 >> shift,
+ 0x70000000 >> shift);
+ if (!iova) {
+ err = -ENOMEM;
+ goto detach_group;
+ }
+
+ /*
+ * BSEV's end addresses wraps around due to integer overflow on
+ * hardware context set up if IOVA is allocated at the end of
+ * address space and VDE can't handle that. Hence simply reserve
+ * the last page to avoid the problem.
+ */
+ iova = reserve_iova(&vde->iova, (0xffffffff >> shift) - 1,
+ 0xffffffff >> shift);
+ if (!iova) {
+ err = -ENOMEM;
+ goto detach_group;
+ }
+
+ return 0;
+
+detach_group:
+ iommu_detach_group(vde->domain, vde->group);
+put_iova:
+ put_iova_domain(&vde->iova);
+ iova_cache_put();
+free_domain:
+ iommu_domain_free(vde->domain);
+put_group:
+ iommu_group_put(vde->group);
+
+ return err;
+}
+
+void tegra_vde_iommu_deinit(struct tegra_vde *vde)
+{
+ if (vde->domain) {
+ iommu_detach_group(vde->domain, vde->group);
+ put_iova_domain(&vde->iova);
+ iova_cache_put();
+ iommu_domain_free(vde->domain);
+ iommu_group_put(vde->group);
+ }
+}
diff --git a/drivers/staging/media/tegra-vde/trace.h b/drivers/staging/media/tegra-vde/trace.h
index 85e2f7e2d4d0..c7e7d6f5fd4c 100644
--- a/drivers/staging/media/tegra-vde/trace.h
+++ b/drivers/staging/media/tegra-vde/trace.h
@@ -7,6 +7,7 @@
#define TEGRA_VDE_TRACE_H

#include <linux/tracepoint.h>
+#include "vde.h"

DECLARE_EVENT_CLASS(register_access,
TP_PROTO(struct tegra_vde *vde, void __iomem *base,
diff --git a/drivers/staging/media/tegra-vde/tegra-vde.c b/drivers/staging/media/tegra-vde/vde.c
similarity index 91%
rename from drivers/staging/media/tegra-vde/tegra-vde.c
rename to drivers/staging/media/tegra-vde/vde.c
index cc4244da2705..cbcdbfef072d 100644
--- a/drivers/staging/media/tegra-vde/tegra-vde.c
+++ b/drivers/staging/media/tegra-vde/vde.c
@@ -22,6 +22,10 @@
#include <soc/tegra/pmc.h>

#include "uapi.h"
+#include "vde.h"
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"

#define ICMDQUE_WR 0x00
#define CMDQUE_CONTROL 0x08
@@ -33,6 +37,10 @@
#define BSE_DMA_BUSY BIT(23)

struct video_frame {
+ struct iova *y_iova;
+ struct iova *cb_iova;
+ struct iova *cr_iova;
+ struct iova *aux_iova;
struct dma_buf_attachment *y_dmabuf_attachment;
struct dma_buf_attachment *cb_dmabuf_attachment;
struct dma_buf_attachment *cr_dmabuf_attachment;
@@ -49,63 +57,6 @@ struct video_frame {
u32 flags;
};

-struct tegra_vde {
- void __iomem *sxe;
- void __iomem *bsev;
- void __iomem *mbe;
- void __iomem *ppe;
- void __iomem *mce;
- void __iomem *tfe;
- void __iomem *ppb;
- void __iomem *vdma;
- void __iomem *frameid;
- struct mutex lock;
- struct miscdevice miscdev;
- struct reset_control *rst;
- struct reset_control *rst_mc;
- struct gen_pool *iram_pool;
- struct completion decode_completion;
- struct clk *clk;
- dma_addr_t iram_lists_addr;
- u32 *iram;
-};
-
-static __maybe_unused char const *
-tegra_vde_reg_base_name(struct tegra_vde *vde, void __iomem *base)
-{
- if (vde->sxe == base)
- return "SXE";
-
- if (vde->bsev == base)
- return "BSEV";
-
- if (vde->mbe == base)
- return "MBE";
-
- if (vde->ppe == base)
- return "PPE";
-
- if (vde->mce == base)
- return "MCE";
-
- if (vde->tfe == base)
- return "TFE";
-
- if (vde->ppb == base)
- return "PPB";
-
- if (vde->vdma == base)
- return "VDMA";
-
- if (vde->frameid == base)
- return "FRAMEID";
-
- return "???";
-}
-
-#define CREATE_TRACE_POINTS
-#include "trace.h"
-
static void tegra_vde_writel(struct tegra_vde *vde,
u32 value, void __iomem *base, u32 offset)
{
@@ -543,28 +494,35 @@ static void tegra_vde_decode_frame(struct tegra_vde *vde,
vde->sxe, 0x00);
}

-static void tegra_vde_detach_and_put_dmabuf(struct dma_buf_attachment *a,
+static void tegra_vde_detach_and_put_dmabuf(struct tegra_vde *vde,
+ enum dma_data_direction dma_dir,
+ struct dma_buf_attachment *a,
struct sg_table *sgt,
- enum dma_data_direction dma_dir)
+ struct iova *iova)
{
struct dma_buf *dmabuf = a->dmabuf;

+ if (vde->domain)
+ tegra_vde_iommu_unmap(vde, iova);
+
dma_buf_unmap_attachment(a, sgt, dma_dir);
dma_buf_detach(dmabuf, a);
dma_buf_put(dmabuf);
}

-static int tegra_vde_attach_dmabuf(struct device *dev,
+static int tegra_vde_attach_dmabuf(struct tegra_vde *vde,
int fd,
unsigned long offset,
size_t min_size,
size_t align_size,
struct dma_buf_attachment **a,
- dma_addr_t *addr,
+ dma_addr_t *addrp,
struct sg_table **s,
+ struct iova **iovap,
size_t *size,
enum dma_data_direction dma_dir)
{
+ struct device *dev = vde->miscdev.parent;
struct dma_buf_attachment *attachment;
struct dma_buf *dmabuf;
struct sg_table *sgt;
@@ -602,13 +560,23 @@ static int tegra_vde_attach_dmabuf(struct device *dev,
goto err_detach;
}

- if (sgt->nents != 1) {
- dev_err(dev, "Sparse DMA region is unsupported\n");
+ if (!vde->domain && sgt->nents > 1) {
+ dev_err(dev, "Sparse DMA region is unsupported, please enable IOMMU\n");
err = -EINVAL;
goto err_unmap;
}

- *addr = sg_dma_address(sgt->sgl) + offset;
+ if (vde->domain) {
+ err = tegra_vde_iommu_map(vde, sgt, iovap, addrp, dmabuf->size);
+ if (err) {
+ dev_err(dev, "IOMMU mapping failed: %d\n", err);
+ goto err_unmap;
+ }
+ } else {
+ *addrp = sg_dma_address(sgt->sgl);
+ }
+
+ *addrp = *addrp + offset;
*a = attachment;
*s = sgt;

@@ -627,7 +595,7 @@ static int tegra_vde_attach_dmabuf(struct device *dev,
return err;
}

-static int tegra_vde_attach_dmabufs_to_frame(struct device *dev,
+static int tegra_vde_attach_dmabufs_to_frame(struct tegra_vde *vde,
struct video_frame *frame,
struct tegra_vde_h264_frame *src,
enum dma_data_direction dma_dir,
@@ -636,29 +604,32 @@ static int tegra_vde_attach_dmabufs_to_frame(struct device *dev,
{
int err;

- err = tegra_vde_attach_dmabuf(dev, src->y_fd,
+ err = tegra_vde_attach_dmabuf(vde, src->y_fd,
src->y_offset, lsize, SZ_256,
&frame->y_dmabuf_attachment,
&frame->y_addr,
&frame->y_sgt,
+ &frame->y_iova,
NULL, dma_dir);
if (err)
return err;

- err = tegra_vde_attach_dmabuf(dev, src->cb_fd,
+ err = tegra_vde_attach_dmabuf(vde, src->cb_fd,
src->cb_offset, csize, SZ_256,
&frame->cb_dmabuf_attachment,
&frame->cb_addr,
&frame->cb_sgt,
+ &frame->cb_iova,
NULL, dma_dir);
if (err)
goto err_release_y;

- err = tegra_vde_attach_dmabuf(dev, src->cr_fd,
+ err = tegra_vde_attach_dmabuf(vde, src->cr_fd,
src->cr_offset, csize, SZ_256,
&frame->cr_dmabuf_attachment,
&frame->cr_addr,
&frame->cr_sgt,
+ &frame->cr_iova,
NULL, dma_dir);
if (err)
goto err_release_cb;
@@ -668,11 +639,12 @@ static int tegra_vde_attach_dmabufs_to_frame(struct device *dev,
return 0;
}

- err = tegra_vde_attach_dmabuf(dev, src->aux_fd,
+ err = tegra_vde_attach_dmabuf(vde, src->aux_fd,
src->aux_offset, csize, SZ_256,
&frame->aux_dmabuf_attachment,
&frame->aux_addr,
&frame->aux_sgt,
+ &frame->aux_iova,
NULL, dma_dir);
if (err)
goto err_release_cr;
@@ -680,34 +652,49 @@ static int tegra_vde_attach_dmabufs_to_frame(struct device *dev,
return 0;

err_release_cr:
- tegra_vde_detach_and_put_dmabuf(frame->cr_dmabuf_attachment,
- frame->cr_sgt, dma_dir);
+ tegra_vde_detach_and_put_dmabuf(vde, dma_dir,
+ frame->cr_dmabuf_attachment,
+ frame->cr_sgt,
+ frame->cr_iova);
err_release_cb:
- tegra_vde_detach_and_put_dmabuf(frame->cb_dmabuf_attachment,
- frame->cb_sgt, dma_dir);
+ tegra_vde_detach_and_put_dmabuf(vde, dma_dir,
+ frame->cb_dmabuf_attachment,
+ frame->cb_sgt,
+ frame->cb_iova);
err_release_y:
- tegra_vde_detach_and_put_dmabuf(frame->y_dmabuf_attachment,
- frame->y_sgt, dma_dir);
+ tegra_vde_detach_and_put_dmabuf(vde, dma_dir,
+ frame->y_dmabuf_attachment,
+ frame->y_sgt,
+ frame->y_iova);

return err;
}

-static void tegra_vde_release_frame_dmabufs(struct video_frame *frame,
+static void tegra_vde_release_frame_dmabufs(struct tegra_vde *vde,
+ struct video_frame *frame,
enum dma_data_direction dma_dir,
bool baseline_profile)
{
if (!baseline_profile)
- tegra_vde_detach_and_put_dmabuf(frame->aux_dmabuf_attachment,
- frame->aux_sgt, dma_dir);
-
- tegra_vde_detach_and_put_dmabuf(frame->cr_dmabuf_attachment,
- frame->cr_sgt, dma_dir);
-
- tegra_vde_detach_and_put_dmabuf(frame->cb_dmabuf_attachment,
- frame->cb_sgt, dma_dir);
-
- tegra_vde_detach_and_put_dmabuf(frame->y_dmabuf_attachment,
- frame->y_sgt, dma_dir);
+ tegra_vde_detach_and_put_dmabuf(vde, dma_dir,
+ frame->aux_dmabuf_attachment,
+ frame->aux_sgt,
+ frame->aux_iova);
+
+ tegra_vde_detach_and_put_dmabuf(vde, dma_dir,
+ frame->cr_dmabuf_attachment,
+ frame->cr_sgt,
+ frame->cr_iova);
+
+ tegra_vde_detach_and_put_dmabuf(vde, dma_dir,
+ frame->cb_dmabuf_attachment,
+ frame->cb_sgt,
+ frame->cb_iova);
+
+ tegra_vde_detach_and_put_dmabuf(vde, dma_dir,
+ frame->y_dmabuf_attachment,
+ frame->y_sgt,
+ frame->y_iova);
}

static int tegra_vde_validate_frame(struct device *dev,
@@ -800,6 +787,7 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde,
struct video_frame *dpb_frames;
struct dma_buf_attachment *bitstream_data_dmabuf_attachment;
struct sg_table *bitstream_sgt;
+ struct iova *bitstream_iova;
enum dma_data_direction dma_dir;
dma_addr_t bitstream_data_addr;
dma_addr_t bsev_ptr;
@@ -819,12 +807,13 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde,
if (ret)
return ret;

- ret = tegra_vde_attach_dmabuf(dev, ctx.bitstream_data_fd,
+ ret = tegra_vde_attach_dmabuf(vde, ctx.bitstream_data_fd,
ctx.bitstream_data_offset,
SZ_16K, SZ_16K,
&bitstream_data_dmabuf_attachment,
&bitstream_data_addr,
&bitstream_sgt,
+ &bitstream_iova,
&bitstream_data_size,
DMA_TO_DEVICE);
if (ret)
@@ -866,7 +855,7 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde,

dma_dir = (i == 0) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;

- ret = tegra_vde_attach_dmabufs_to_frame(dev, &dpb_frames[i],
+ ret = tegra_vde_attach_dmabufs_to_frame(vde, &dpb_frames[i],
&frames[i], dma_dir,
ctx.baseline_profile,
lsize, csize);
@@ -954,7 +943,7 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde,
while (i--) {
dma_dir = (i == 0) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;

- tegra_vde_release_frame_dmabufs(&dpb_frames[i], dma_dir,
+ tegra_vde_release_frame_dmabufs(vde, &dpb_frames[i], dma_dir,
ctx.baseline_profile);
}

@@ -965,8 +954,10 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde,
kfree(frames);

release_bitstream_dmabuf:
- tegra_vde_detach_and_put_dmabuf(bitstream_data_dmabuf_attachment,
- bitstream_sgt, DMA_TO_DEVICE);
+ tegra_vde_detach_and_put_dmabuf(vde, DMA_TO_DEVICE,
+ bitstream_data_dmabuf_attachment,
+ bitstream_sgt,
+ bitstream_iova);

return ret;
}
@@ -1176,10 +1167,16 @@ static int tegra_vde_probe(struct platform_device *pdev)
vde->miscdev.fops = &tegra_vde_fops;
vde->miscdev.parent = dev;

+ err = tegra_vde_iommu_init(vde);
+ if (err) {
+ dev_err(dev, "Failed to initialize IOMMU: %d\n", err);
+ goto err_gen_free;
+ }
+
err = misc_register(&vde->miscdev);
if (err) {
dev_err(dev, "Failed to register misc device: %d\n", err);
- goto err_gen_free;
+ goto err_deinit_iommu;
}

pm_runtime_enable(dev);
@@ -1197,6 +1194,9 @@ static int tegra_vde_probe(struct platform_device *pdev)
err_misc_unreg:
misc_deregister(&vde->miscdev);

+err_deinit_iommu:
+ tegra_vde_iommu_deinit(vde);
+
err_gen_free:
gen_pool_free(vde->iram_pool, (unsigned long)vde->iram,
gen_pool_size(vde->iram_pool));
@@ -1221,6 +1221,8 @@ static int tegra_vde_remove(struct platform_device *pdev)

misc_deregister(&vde->miscdev);

+ tegra_vde_iommu_deinit(vde);
+
gen_pool_free(vde->iram_pool, (unsigned long)vde->iram,
gen_pool_size(vde->iram_pool));

diff --git a/drivers/staging/media/tegra-vde/vde.h b/drivers/staging/media/tegra-vde/vde.h
new file mode 100644
index 000000000000..37414b7fdee1
--- /dev/null
+++ b/drivers/staging/media/tegra-vde/vde.h
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * NVIDIA Tegra Video decoder driver
+ *
+ * Copyright (C) 2016-2019 GRATE-DRIVER project
+ */
+
+#ifndef TEGRA_VDE_H
+#define TEGRA_VDE_H
+
+#include <linux/completion.h>
+#include <linux/miscdevice.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+#include <linux/iova.h>
+
+struct clk;
+struct gen_pool;
+struct iommu_group;
+struct iommu_domain;
+struct reset_control;
+
+struct tegra_vde {
+ void __iomem *sxe;
+ void __iomem *bsev;
+ void __iomem *mbe;
+ void __iomem *ppe;
+ void __iomem *mce;
+ void __iomem *tfe;
+ void __iomem *ppb;
+ void __iomem *vdma;
+ void __iomem *frameid;
+ struct mutex lock;
+ struct miscdevice miscdev;
+ struct reset_control *rst;
+ struct reset_control *rst_mc;
+ struct gen_pool *iram_pool;
+ struct completion decode_completion;
+ struct clk *clk;
+ struct iommu_domain *domain;
+ struct iommu_group *group;
+ struct iova_domain iova;
+ dma_addr_t iram_lists_addr;
+ u32 *iram;
+};
+
+int tegra_vde_iommu_init(struct tegra_vde *vde);
+void tegra_vde_iommu_deinit(struct tegra_vde *vde);
+int tegra_vde_iommu_map(struct tegra_vde *vde,
+ struct sg_table *sgt,
+ struct iova **iovap,
+ dma_addr_t *addrp,
+ size_t size);
+void tegra_vde_iommu_unmap(struct tegra_vde *vde, struct iova *iova);
+
+static __maybe_unused char const *
+tegra_vde_reg_base_name(struct tegra_vde *vde, void __iomem *base)
+{
+ if (vde->sxe == base)
+ return "SXE";
+
+ if (vde->bsev == base)
+ return "BSEV";
+
+ if (vde->mbe == base)
+ return "MBE";
+
+ if (vde->ppe == base)
+ return "PPE";
+
+ if (vde->mce == base)
+ return "MCE";
+
+ if (vde->tfe == base)
+ return "TFE";
+
+ if (vde->ppb == base)
+ return "PPB";
+
+ if (vde->vdma == base)
+ return "VDMA";
+
+ if (vde->frameid == base)
+ return "FRAMEID";
+
+ return "???";
+}
+
+#endif /* TEGRA_VDE_H */
--
2.21.0