* [PATCH V2] accel/amdxdna: Add carveout memory support for non-IOMMU systems
@ 2026-04-27 17:09 Lizhi Hou
2026-05-04 19:08 ` Mario Limonciello
0 siblings, 1 reply; 3+ messages in thread
From: Lizhi Hou @ 2026-04-27 17:09 UTC (permalink / raw)
To: ogabbay, quic_jhugo, dri-devel, mario.limonciello,
maciej.falkowski
Cc: Max Zhen, linux-kernel, sonal.santan, Lizhi Hou
From: Max Zhen <max.zhen@amd.com>
Add support for allocating buffers from reserved carveout memory when
IOMMU is not available. This is useful during debugging or bring-up.
In this configuration, the device uses physical addresses and does
not support scatter-gather lists, requiring physically contiguous
buffers.
Implement carveout-backed allocation and integrate it into buffer
management to support operation in physical address mode.
Signed-off-by: Max Zhen <max.zhen@amd.com>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
---
drivers/accel/amdxdna/Makefile | 2 +
drivers/accel/amdxdna/amdxdna_cbuf.c | 280 ++++++++++++++++++++++++
drivers/accel/amdxdna/amdxdna_cbuf.h | 18 ++
drivers/accel/amdxdna/amdxdna_debugfs.c | 129 +++++++++++
drivers/accel/amdxdna/amdxdna_debugfs.h | 18 ++
drivers/accel/amdxdna/amdxdna_gem.c | 95 ++++++--
drivers/accel/amdxdna/amdxdna_iommu.c | 77 ++++---
drivers/accel/amdxdna/amdxdna_pci_drv.c | 89 +++++---
drivers/accel/amdxdna/amdxdna_pci_drv.h | 8 +-
9 files changed, 636 insertions(+), 80 deletions(-)
create mode 100644 drivers/accel/amdxdna/amdxdna_cbuf.c
create mode 100644 drivers/accel/amdxdna/amdxdna_cbuf.h
create mode 100644 drivers/accel/amdxdna/amdxdna_debugfs.c
create mode 100644 drivers/accel/amdxdna/amdxdna_debugfs.h
diff --git a/drivers/accel/amdxdna/Makefile b/drivers/accel/amdxdna/Makefile
index 79369e497540..d7720c8c8a98 100644
--- a/drivers/accel/amdxdna/Makefile
+++ b/drivers/accel/amdxdna/Makefile
@@ -12,6 +12,7 @@ amdxdna-y := \
aie2_solver.o \
aie4_message.o \
aie4_pci.o \
+ amdxdna_cbuf.o \
amdxdna_ctx.o \
amdxdna_gem.o \
amdxdna_iommu.o \
@@ -28,4 +29,5 @@ amdxdna-y := \
npu6_regs.o
amdxdna-$(CONFIG_PCI_IOV) += aie4_sriov.o
+amdxdna-$(CONFIG_DEBUG_FS) += amdxdna_debugfs.o
obj-$(CONFIG_DRM_ACCEL_AMDXDNA) = amdxdna.o
diff --git a/drivers/accel/amdxdna/amdxdna_cbuf.c b/drivers/accel/amdxdna/amdxdna_cbuf.c
new file mode 100644
index 000000000000..a504560aae98
--- /dev/null
+++ b/drivers/accel/amdxdna/amdxdna_cbuf.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2026, Advanced Micro Devices, Inc.
+ */
+
+#include <drm/drm_mm.h>
+#include <drm/drm_prime.h>
+
+#include "amdxdna_cbuf.h"
+#include "amdxdna_pci_drv.h"
+
+/*
+ * Carveout memory is a chunk of memory which is physically contiguous and
+ * is reserved during early boot time. There is only one chunk of such memory
+ * per device. Once available, all BOs accessible from device should be
+ * allocated from this memory. This is a platform debug/bringup feature.
+ */
+struct amdxdna_carveout {
+ u64 addr;
+ u64 size;
+ struct drm_mm mm;
+ struct mutex lock; /* protect mm */
+};
+
+bool amdxdna_use_carveout(struct amdxdna_dev *xdna)
+{
+ return !!xdna->carveout;
+}
+
+void amdxdna_get_carveout_conf(struct amdxdna_dev *xdna, u64 *addr, u64 *size)
+{
+ if (amdxdna_use_carveout(xdna)) {
+ *addr = xdna->carveout->addr;
+ *size = xdna->carveout->size;
+ } else {
+ *addr = 0;
+ *size = 0;
+ }
+}
+
+int amdxdna_carveout_init(struct amdxdna_dev *xdna, u64 carveout_addr, u64 carveout_size)
+{
+ struct amdxdna_carveout *carveout;
+
+ /* Only allow carveout memory to be set up once. */
+ if (amdxdna_use_carveout(xdna)) {
+ XDNA_ERR(xdna, "Carveout memory has already been set up.");
+ return -EBUSY;
+ }
+
+ carveout = kzalloc_obj(*carveout);
+ if (!carveout)
+ return -ENOMEM;
+
+ carveout->addr = carveout_addr;
+ carveout->size = carveout_size;
+ mutex_init(&carveout->lock);
+ drm_mm_init(&carveout->mm, carveout->addr, carveout->size);
+
+ xdna->carveout = carveout;
+ XDNA_INFO(xdna, "Use carveout mem: 0x%llx@0x%llx\n", carveout->size, carveout->addr);
+ return 0;
+}
+
+void amdxdna_carveout_fini(struct amdxdna_dev *xdna)
+{
+ struct amdxdna_carveout *carveout = xdna->carveout;
+
+ if (!amdxdna_use_carveout(xdna))
+ return;
+
+ XDNA_INFO(xdna, "Cleanup carveout mem: 0x%llx@0x%llx\n", carveout->size, carveout->addr);
+ drm_mm_takedown(&carveout->mm);
+ mutex_destroy(&carveout->lock);
+ kfree(carveout);
+ xdna->carveout = NULL;
+}
+
+struct amdxdna_cbuf_priv {
+ struct amdxdna_dev *xdna;
+ struct drm_mm_node node;
+};
+
+static struct sg_table *amdxdna_cbuf_map(struct dma_buf_attachment *attach,
+ enum dma_data_direction direction)
+{
+ struct amdxdna_cbuf_priv *cbuf = attach->dmabuf->priv;
+ struct device *dev = attach->dev;
+ struct scatterlist *sgl, *sg;
+ int ret, n_entries, i;
+ struct sg_table *sgt;
+ dma_addr_t dma_addr;
+ size_t dma_size;
+ size_t max_seg;
+
+ sgt = kzalloc_obj(*sgt);
+ if (!sgt)
+ return ERR_PTR(-ENOMEM);
+
+ max_seg = min_t(size_t, UINT_MAX, dma_max_mapping_size(dev));
+ n_entries = (cbuf->node.size + max_seg - 1) / max_seg;
+ sgl = kzalloc_objs(*sg, n_entries);
+ if (!sgl) {
+ ret = -ENOMEM;
+ goto free_sgt;
+ }
+ sg_init_table(sgl, n_entries);
+ sgt->orig_nents = n_entries;
+ sgt->nents = n_entries;
+ sgt->sgl = sgl;
+
+ dma_size = cbuf->node.size;
+ dma_addr = dma_map_resource(dev, cbuf->node.start, dma_size,
+ direction, DMA_ATTR_SKIP_CPU_SYNC);
+ ret = dma_mapping_error(dev, dma_addr);
+ if (ret) {
+ pr_err("Failed to dma_map_resource carveout dma buf, ret %d\n", ret);
+ goto free_sgl;
+ }
+
+ for_each_sgtable_dma_sg(sgt, sg, i) {
+ size_t len = min_t(size_t, max_seg, dma_size);
+
+ sg_dma_address(sg) = dma_addr;
+ sg_dma_len(sg) = len;
+ dma_addr += len;
+ dma_size -= len;
+ }
+
+ return sgt;
+
+free_sgl:
+ kfree(sgl);
+free_sgt:
+ kfree(sgt);
+ return ERR_PTR(ret);
+}
+
+static void amdxdna_cbuf_unmap(struct dma_buf_attachment *attach,
+ struct sg_table *sgt,
+ enum dma_data_direction direction)
+{
+ dma_unmap_resource(attach->dev, sg_dma_address(sgt->sgl),
+ drm_prime_get_contiguous_size(sgt), direction,
+ DMA_ATTR_SKIP_CPU_SYNC);
+ sg_free_table(sgt);
+ kfree(sgt);
+}
+
+static void amdxdna_cbuf_release(struct dma_buf *dbuf)
+{
+ struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
+ struct amdxdna_carveout *carveout;
+
+ carveout = cbuf->xdna->carveout;
+ mutex_lock(&carveout->lock);
+ drm_mm_remove_node(&cbuf->node);
+ mutex_unlock(&carveout->lock);
+
+ kfree(cbuf);
+}
+
+static vm_fault_t amdxdna_cbuf_vm_fault(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct amdxdna_cbuf_priv *cbuf;
+ unsigned long pfn;
+ pgoff_t pgoff;
+
+ cbuf = vma->vm_private_data;
+ pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+ pfn = (cbuf->node.start >> PAGE_SHIFT) + pgoff;
+
+ return vmf_insert_pfn(vma, vmf->address, pfn);
+}
+
+static const struct vm_operations_struct amdxdna_cbuf_vm_ops = {
+ .fault = amdxdna_cbuf_vm_fault,
+};
+
+static int amdxdna_cbuf_mmap(struct dma_buf *dbuf, struct vm_area_struct *vma)
+{
+ struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
+
+ vma->vm_ops = &amdxdna_cbuf_vm_ops;
+ vma->vm_private_data = cbuf;
+ vm_flags_set(vma, VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP);
+
+ return 0;
+}
+
+static int amdxdna_cbuf_vmap(struct dma_buf *dbuf, struct iosys_map *map)
+{
+ struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
+ void *kva;
+
+ kva = memremap(cbuf->node.start, cbuf->node.size, MEMREMAP_WB);
+ if (!kva) {
+ pr_err("Failed to vmap carveout dma buf\n");
+ return -ENOMEM;
+ }
+
+ iosys_map_set_vaddr(map, kva);
+ return 0;
+}
+
+static void amdxdna_cbuf_vunmap(struct dma_buf *dbuf, struct iosys_map *map)
+{
+ memunmap(map->vaddr);
+}
+
+static const struct dma_buf_ops amdxdna_cbuf_dmabuf_ops = {
+ .map_dma_buf = amdxdna_cbuf_map,
+ .unmap_dma_buf = amdxdna_cbuf_unmap,
+ .release = amdxdna_cbuf_release,
+ .mmap = amdxdna_cbuf_mmap,
+ .vmap = amdxdna_cbuf_vmap,
+ .vunmap = amdxdna_cbuf_vunmap,
+};
+
+static int amdxdna_cbuf_clear(struct dma_buf *dbuf)
+{
+ struct iosys_map vmap = IOSYS_MAP_INIT_VADDR(NULL);
+
+ dma_buf_vmap(dbuf, &vmap);
+ if (!vmap.vaddr)
+ return -EFAULT;
+
+ memset(vmap.vaddr, 0, dbuf->size);
+ dma_buf_vunmap(dbuf, &vmap);
+
+ return 0;
+}
+
+struct dma_buf *amdxdna_get_cbuf(struct drm_device *dev, size_t size, u64 alignment)
+{
+ struct amdxdna_dev *xdna = to_xdna_dev(dev);
+ DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+ struct amdxdna_carveout *carveout;
+ struct amdxdna_cbuf_priv *cbuf;
+ struct dma_buf *dbuf;
+ int ret;
+
+ cbuf = kzalloc_obj(*cbuf);
+ if (!cbuf)
+ return ERR_PTR(-ENOMEM);
+ cbuf->xdna = xdna;
+
+ carveout = xdna->carveout;
+ mutex_lock(&carveout->lock);
+ ret = drm_mm_insert_node_generic(&carveout->mm, &cbuf->node, size,
+ alignment, 0, DRM_MM_INSERT_BEST);
+ mutex_unlock(&carveout->lock);
+ if (ret)
+ goto free_cbuf;
+
+ exp_info.size = size;
+ exp_info.ops = &amdxdna_cbuf_dmabuf_ops;
+ exp_info.priv = cbuf;
+ exp_info.flags = O_RDWR;
+ dbuf = dma_buf_export(&exp_info);
+ if (IS_ERR(dbuf)) {
+ ret = PTR_ERR(dbuf);
+ goto remove_node;
+ }
+
+ ret = amdxdna_cbuf_clear(dbuf);
+ if (ret) {
+ dma_buf_put(dbuf);
+ goto out;
+ }
+ return dbuf;
+
+remove_node:
+ drm_mm_remove_node(&cbuf->node);
+free_cbuf:
+ kfree(cbuf);
+out:
+ return ERR_PTR(ret);
+}
diff --git a/drivers/accel/amdxdna/amdxdna_cbuf.h b/drivers/accel/amdxdna/amdxdna_cbuf.h
new file mode 100644
index 000000000000..8e89336ffd50
--- /dev/null
+++ b/drivers/accel/amdxdna/amdxdna_cbuf.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2026, Advanced Micro Devices, Inc.
+ */
+#ifndef _AMDXDNA_CBUF_H_
+#define _AMDXDNA_CBUF_H_
+
+#include "amdxdna_pci_drv.h"
+#include <drm/drm_device.h>
+#include <linux/dma-buf.h>
+
+bool amdxdna_use_carveout(struct amdxdna_dev *xdna);
+int amdxdna_carveout_init(struct amdxdna_dev *xdna, u64 carveout_addr, u64 carveout_size);
+void amdxdna_carveout_fini(struct amdxdna_dev *xdna);
+void amdxdna_get_carveout_conf(struct amdxdna_dev *xdna, u64 *addr, u64 *size);
+struct dma_buf *amdxdna_get_cbuf(struct drm_device *dev, size_t size, u64 alignment);
+
+#endif
diff --git a/drivers/accel/amdxdna/amdxdna_debugfs.c b/drivers/accel/amdxdna/amdxdna_debugfs.c
new file mode 100644
index 000000000000..a6ec17c63629
--- /dev/null
+++ b/drivers/accel/amdxdna/amdxdna_debugfs.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2026, Advanced Micro Devices, Inc.
+ */
+
+#include "amdxdna_cbuf.h"
+#include "amdxdna_debugfs.h"
+
+#include <drm/drm_file.h>
+#include <linux/debugfs.h>
+#include <linux/pm_runtime.h>
+#include <linux/seq_file.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+
+#define _DBGFS_FOPS(_open, _release, _write) \
+{ \
+ .owner = THIS_MODULE, \
+ .open = _open, \
+ .read = seq_read, \
+ .llseek = seq_lseek, \
+ .release = _release, \
+ .write = _write, \
+}
+
+#define AMDXDNA_DBGFS_FOPS(_name, _show, _write) \
+ static int amdxdna_dbgfs_##_name##_open(struct inode *inode, struct file *file) \
+ { \
+ return single_open(file, _show, inode->i_private); \
+ } \
+ static int amdxdna_dbgfs_##_name##_release(struct inode *inode, struct file *file) \
+ { \
+ return single_release(inode, file); \
+ } \
+ static const struct file_operations amdxdna_fops_##_name = \
+ _DBGFS_FOPS(amdxdna_dbgfs_##_name##_open, amdxdna_dbgfs_##_name##_release, _write)
+
+#define AMDXDNA_DBGFS_FILE(_name, _mode) { #_name, &amdxdna_fops_##_name, _mode }
+
+#define file_to_xdna(file) (((struct seq_file *)(file)->private_data)->private)
+
+static ssize_t amdxdna_carveout_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct amdxdna_dev *xdna = file_to_xdna(file);
+ char kbuf[128];
+ u64 size, addr;
+ char *sep;
+ int ret;
+
+ if (count == 0 || count >= sizeof(kbuf))
+ return -EINVAL;
+
+ if (copy_from_user(kbuf, buf, count))
+ return -EFAULT;
+ kbuf[count] = '\0';
+ strim(kbuf);
+ XDNA_DBG(xdna, "Trying to set carveout to %s", kbuf);
+
+ sep = strchr(kbuf, '@');
+ if (!sep)
+ return -EINVAL;
+ *sep = '\0';
+ sep++;
+
+ ret = kstrtou64(kbuf, 0, &size);
+ if (ret)
+ return ret;
+
+ ret = kstrtou64(sep, 0, &addr);
+ if (ret)
+ return ret;
+
+ /* Sanity check the addr and size. */
+ if (!size)
+ return -EINVAL;
+ if (!IS_ALIGNED(addr, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE))
+ return -EINVAL;
+
+ guard(mutex)(&xdna->dev_lock);
+
+ ret = amdxdna_carveout_init(xdna, addr, size);
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+static int amdxdna_carveout_show(struct seq_file *m, void *unused)
+{
+ struct amdxdna_dev *xdna = m->private;
+ u64 addr, size;
+
+ guard(mutex)(&xdna->dev_lock);
+ amdxdna_get_carveout_conf(xdna, &addr, &size);
+ seq_printf(m, "0x%llx@0x%llx\n", size, addr);
+ return 0;
+}
+
+/*
+ * Input/output format: <carveout_size>@<carveout_address>
+ */
+AMDXDNA_DBGFS_FOPS(carveout, amdxdna_carveout_show, amdxdna_carveout_write);
+
+static const struct {
+ const char *name;
+ const struct file_operations *fops;
+ umode_t mode;
+} amdxdna_dbgfs_files[] = {
+ AMDXDNA_DBGFS_FILE(carveout, 0600),
+};
+
+void amdxdna_debugfs_init(struct amdxdna_dev *xdna)
+{
+ struct drm_minor *minor = xdna->ddev.accel;
+ int i;
+
+ /*
+ * It should be okay that debugfs fails to init.
+ * We rely on DRM framework to finish debugfs.
+ */
+ for (i = 0; i < ARRAY_SIZE(amdxdna_dbgfs_files); i++) {
+ debugfs_create_file(amdxdna_dbgfs_files[i].name,
+ amdxdna_dbgfs_files[i].mode,
+ minor->debugfs_root,
+ xdna,
+ amdxdna_dbgfs_files[i].fops);
+ }
+}
diff --git a/drivers/accel/amdxdna/amdxdna_debugfs.h b/drivers/accel/amdxdna/amdxdna_debugfs.h
new file mode 100644
index 000000000000..2abb45de3f7e
--- /dev/null
+++ b/drivers/accel/amdxdna/amdxdna_debugfs.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2026, Advanced Micro Devices, Inc.
+ */
+#ifndef _AMDXDNA_DEBUGFS_H_
+#define _AMDXDNA_DEBUGFS_H_
+
+#include "amdxdna_pci_drv.h"
+
+#if defined(CONFIG_DEBUG_FS)
+void amdxdna_debugfs_init(struct amdxdna_dev *xdna);
+#else
+static inline void amdxdna_debugfs_init(struct amdxdna_dev *xdna)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+#endif
diff --git a/drivers/accel/amdxdna/amdxdna_gem.c b/drivers/accel/amdxdna/amdxdna_gem.c
index 238ee244d4a6..ebfc472aa9e7 100644
--- a/drivers/accel/amdxdna/amdxdna_gem.c
+++ b/drivers/accel/amdxdna/amdxdna_gem.c
@@ -16,6 +16,7 @@
#include <linux/pagemap.h>
#include <linux/vmalloc.h>
+#include "amdxdna_cbuf.h"
#include "amdxdna_ctx.h"
#include "amdxdna_gem.h"
#include "amdxdna_pci_drv.h"
@@ -516,10 +517,6 @@ static void amdxdna_imported_obj_free(struct amdxdna_gem_obj *abo)
static inline bool
amdxdna_gem_skip_bo_usage(struct amdxdna_gem_obj *abo)
{
- /* Do not count imported BOs since the buffer is not allocated by us. */
- if (is_import_bo(abo))
- return true;
-
/* Already counted as part of HEAP BO */
if (abo->type == AMDXDNA_BO_DEV)
return true;
@@ -571,9 +568,7 @@ static void amdxdna_gem_obj_free(struct drm_gem_object *gobj)
if (abo->type == AMDXDNA_BO_DEV_HEAP)
drm_mm_takedown(&abo->mm);
- if (amdxdna_iova_on(xdna))
- amdxdna_iommu_unmap_bo(xdna, abo);
-
+ amdxdna_dma_unmap_bo(xdna, abo);
amdxdna_gem_vunmap(abo);
mutex_destroy(&abo->lock);
@@ -591,18 +586,20 @@ static int amdxdna_gem_obj_open(struct drm_gem_object *gobj, struct drm_file *fi
guard(mutex)(&abo->lock);
abo->open_ref++;
+ if (abo->open_ref > 1)
+ return 0;
- if (abo->open_ref == 1) {
- /* Attached to the client when first opened by it. */
- abo->client = filp->driver_priv;
- amdxdna_gem_add_bo_usage(abo);
- }
- if (amdxdna_iova_on(xdna)) {
- ret = amdxdna_iommu_map_bo(xdna, abo);
+ /* Attached to the client when first opened by it. */
+ abo->client = filp->driver_priv;
+
+ /* No need to set up dma addr mapping in PASID mode. */
+ if (!amdxdna_pasid_on(abo->client)) {
+ ret = amdxdna_dma_map_bo(xdna, abo);
if (ret)
return ret;
}
+ amdxdna_gem_add_bo_usage(abo);
return 0;
}
@@ -620,6 +617,39 @@ static void amdxdna_gem_obj_close(struct drm_gem_object *gobj, struct drm_file *
}
}
+static int amdxdna_gem_obj_vmap(struct drm_gem_object *obj, struct iosys_map *map)
+{
+ struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
+ int ret;
+
+ iosys_map_clear(map);
+
+ dma_resv_assert_held(obj->resv);
+
+ if (is_import_bo(abo))
+ ret = dma_buf_vmap(abo->dma_buf, map);
+ else
+ ret = drm_gem_shmem_object_vmap(obj, map);
+ if (ret)
+ return ret;
+ if (!map->vaddr)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void amdxdna_gem_obj_vunmap(struct drm_gem_object *obj, struct iosys_map *map)
+{
+ struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
+
+ dma_resv_assert_held(obj->resv);
+
+ if (is_import_bo(abo))
+ dma_buf_vunmap(abo->dma_buf, map);
+ else
+ drm_gem_shmem_object_vunmap(obj, map);
+}
+
static int amdxdna_gem_dev_obj_vmap(struct drm_gem_object *obj, struct iosys_map *map)
{
struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
@@ -645,8 +675,8 @@ static const struct drm_gem_object_funcs amdxdna_gem_shmem_funcs = {
.pin = drm_gem_shmem_object_pin,
.unpin = drm_gem_shmem_object_unpin,
.get_sg_table = drm_gem_shmem_object_get_sg_table,
- .vmap = drm_gem_shmem_object_vmap,
- .vunmap = drm_gem_shmem_object_vunmap,
+ .vmap = amdxdna_gem_obj_vmap,
+ .vunmap = amdxdna_gem_obj_vunmap,
.mmap = amdxdna_gem_obj_mmap,
.vm_ops = &drm_gem_shmem_vm_ops,
.export = amdxdna_gem_prime_export,
@@ -714,6 +744,36 @@ amdxdna_gem_create_ubuf_object(struct drm_device *dev, struct amdxdna_drm_create
return to_xdna_obj(gobj);
}
+static struct amdxdna_gem_obj *
+amdxdna_gem_create_cbuf_object(struct drm_device *dev, struct amdxdna_drm_create_bo *args)
+{
+ struct amdxdna_dev *xdna = to_xdna_dev(dev);
+ size_t size = PAGE_ALIGN(args->size);
+ struct drm_gem_object *gobj;
+ struct amdxdna_gem_obj *ret;
+ struct dma_buf *dma_buf;
+ u64 align;
+
+ if (!size) {
+ XDNA_ERR(xdna, "Invalid BO size 0x%llx", args->size);
+ return ERR_PTR(-EINVAL);
+ }
+
+ align = (args->type == AMDXDNA_BO_DEV_HEAP) ? xdna->dev_info->dev_mem_size : 0;
+ dma_buf = amdxdna_get_cbuf(dev, size, align);
+ if (IS_ERR(dma_buf))
+ return ERR_CAST(dma_buf);
+
+ gobj = amdxdna_gem_prime_import(dev, dma_buf);
+ if (IS_ERR(gobj))
+ ret = ERR_CAST(gobj);
+ else
+ ret = to_xdna_obj(gobj);
+
+ dma_buf_put(dma_buf);
+ return ret;
+}
+
struct drm_gem_object *
amdxdna_gem_prime_import(struct drm_device *dev, struct dma_buf *dma_buf)
{
@@ -769,6 +829,8 @@ amdxdna_drm_create_share_bo(struct drm_device *dev,
if (args->vaddr)
abo = amdxdna_gem_create_ubuf_object(dev, args);
+ else if (amdxdna_use_carveout(to_xdna_dev(dev)))
+ abo = amdxdna_gem_create_cbuf_object(dev, args);
else
abo = amdxdna_gem_create_shmem_object(dev, args);
if (IS_ERR(abo))
@@ -884,7 +946,6 @@ int amdxdna_drm_create_bo_ioctl(struct drm_device *dev, void *data, struct drm_f
args->type, args->vaddr, args->size, args->flags);
switch (args->type) {
case AMDXDNA_BO_CMD:
- fallthrough;
case AMDXDNA_BO_SHARE:
abo = amdxdna_drm_create_share_bo(dev, args, filp);
break;
diff --git a/drivers/accel/amdxdna/amdxdna_iommu.c b/drivers/accel/amdxdna/amdxdna_iommu.c
index 5a9f06183487..eff00131d0f8 100644
--- a/drivers/accel/amdxdna/amdxdna_iommu.c
+++ b/drivers/accel/amdxdna/amdxdna_iommu.c
@@ -35,14 +35,15 @@ static struct iova *amdxdna_iommu_alloc_iova(struct amdxdna_dev *xdna,
return iova;
}
-int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
+int amdxdna_dma_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
{
+ unsigned long contig_sz;
struct sg_table *sgt;
dma_addr_t dma_addr;
struct iova *iova;
ssize_t size;
- if (abo->type != AMDXDNA_BO_DEV_HEAP && abo->type != AMDXDNA_BO_SHMEM)
+ if (abo->type != AMDXDNA_BO_DEV_HEAP && abo->type != AMDXDNA_BO_SHARE)
return 0;
sgt = drm_gem_shmem_get_pages_sgt(&abo->base);
@@ -51,47 +52,63 @@ int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
return PTR_ERR(sgt);
}
- if (!sgt->orig_nents || !sg_page(sgt->sgl)) {
- XDNA_ERR(xdna, "sgl is zero length or not page backed");
+ if (!sgt->orig_nents) {
+ XDNA_ERR(xdna, "sgl is zero length");
return -EOPNOTSUPP;
}
- iova = amdxdna_iommu_alloc_iova(xdna, abo->mem.size, &dma_addr,
- (abo->type == AMDXDNA_BO_DEV_HEAP));
- if (IS_ERR(iova)) {
- XDNA_ERR(xdna, "Alloc iova failed, ret %ld", PTR_ERR(iova));
- return PTR_ERR(iova);
+ if (amdxdna_iova_on(xdna)) {
+ if (!sg_page(sgt->sgl)) {
+ XDNA_ERR(xdna, "sgl is not page backed");
+ return -EOPNOTSUPP;
+ }
+
+ iova = amdxdna_iommu_alloc_iova(xdna, abo->mem.size, &dma_addr,
+ (abo->type == AMDXDNA_BO_DEV_HEAP));
+ if (IS_ERR(iova)) {
+ XDNA_ERR(xdna, "Alloc iova failed, ret %ld", PTR_ERR(iova));
+ return PTR_ERR(iova);
+ }
+
+ size = iommu_map_sgtable(xdna->domain, dma_addr, sgt,
+ IOMMU_READ | IOMMU_WRITE);
+ if (size < 0) {
+ XDNA_ERR(xdna, "iommu_map_sgtable failed: %zd", size);
+ __free_iova(&xdna->iovad, iova);
+ return size;
+ }
+ if (size < abo->mem.size) {
+ iommu_unmap(xdna->domain, dma_addr, size);
+ __free_iova(&xdna->iovad, iova);
+ return -ENXIO;
+ }
+ abo->mem.dma_addr = dma_addr;
+ } else {
+ /* Device doesn't support scatter/gather list, fail non-contiguous mapping. */
+ contig_sz = drm_prime_get_contiguous_size(sgt);
+ if (contig_sz < abo->mem.size) {
+ XDNA_ERR(xdna,
+ "noncontiguous dma addr, contig size:%ld, expected size:%ld",
+ contig_sz, abo->mem.size);
+ return -EINVAL;
+ }
+ abo->mem.dma_addr = sg_dma_address(sgt->sgl);
}
-
- size = iommu_map_sgtable(xdna->domain, dma_addr, sgt,
- IOMMU_READ | IOMMU_WRITE);
- if (size < 0) {
- XDNA_ERR(xdna, "iommu_map_sgtable failed: %zd", size);
- __free_iova(&xdna->iovad, iova);
- return size;
- }
-
- if (size < abo->mem.size) {
- iommu_unmap(xdna->domain, dma_addr, size);
- __free_iova(&xdna->iovad, iova);
- return -ENXIO;
- }
-
- abo->mem.dma_addr = dma_addr;
-
return 0;
}
-void amdxdna_iommu_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
+void amdxdna_dma_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
{
size_t size;
if (abo->mem.dma_addr == AMDXDNA_INVALID_ADDR)
return;
- size = iova_align(&xdna->iovad, abo->mem.size);
- iommu_unmap(xdna->domain, abo->mem.dma_addr, size);
- free_iova(&xdna->iovad, iova_pfn(&xdna->iovad, abo->mem.dma_addr));
+ if (amdxdna_iova_on(xdna)) {
+ size = iova_align(&xdna->iovad, abo->mem.size);
+ iommu_unmap(xdna->domain, abo->mem.dma_addr, size);
+ free_iova(&xdna->iovad, iova_pfn(&xdna->iovad, abo->mem.dma_addr));
+ }
abo->mem.dma_addr = AMDXDNA_INVALID_ADDR;
}
diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.c b/drivers/accel/amdxdna/amdxdna_pci_drv.c
index 21eddfc538d0..1b08a08343cf 100644
--- a/drivers/accel/amdxdna/amdxdna_pci_drv.c
+++ b/drivers/accel/amdxdna/amdxdna_pci_drv.c
@@ -14,7 +14,9 @@
#include <linux/iommu.h>
#include <linux/pci.h>
+#include "amdxdna_cbuf.h"
#include "amdxdna_ctx.h"
+#include "amdxdna_debugfs.h"
#include "amdxdna_gem.h"
#include "amdxdna_pci_drv.h"
#include "amdxdna_pm.h"
@@ -67,11 +69,40 @@ static const struct amdxdna_device_id amdxdna_ids[] = {
{0}
};
+static int amdxdna_sva_init(struct amdxdna_client *client)
+{
+ struct amdxdna_dev *xdna = client->xdna;
+
+ client->sva = iommu_sva_bind_device(xdna->ddev.dev, client->mm);
+ if (IS_ERR(client->sva)) {
+ XDNA_ERR(xdna, "SVA bind device failed, ret %ld", PTR_ERR(client->sva));
+ return PTR_ERR(client->sva);
+ }
+
+ client->pasid = iommu_sva_get_pasid(client->sva);
+ if (client->pasid == IOMMU_PASID_INVALID) {
+ iommu_sva_unbind_device(client->sva);
+ XDNA_ERR(xdna, "SVA get pasid failed");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static void amdxdna_sva_fini(struct amdxdna_client *client)
+{
+ if (IS_ERR_OR_NULL(client->sva))
+ return;
+
+ iommu_sva_unbind_device(client->sva);
+ client->sva = NULL;
+ client->pasid = IOMMU_PASID_INVALID;
+}
+
static int amdxdna_drm_open(struct drm_device *ddev, struct drm_file *filp)
{
struct amdxdna_dev *xdna = to_xdna_dev(ddev);
struct amdxdna_client *client;
- int ret;
client = kzalloc_obj(*client);
if (!client)
@@ -80,22 +111,13 @@ static int amdxdna_drm_open(struct drm_device *ddev, struct drm_file *filp)
client->pid = pid_nr(rcu_access_pointer(filp->pid));
client->xdna = xdna;
client->pasid = IOMMU_PASID_INVALID;
+ client->mm = current->mm;
if (!amdxdna_iova_on(xdna)) {
- client->sva = iommu_sva_bind_device(xdna->ddev.dev, current->mm);
- if (IS_ERR(client->sva)) {
- ret = PTR_ERR(client->sva);
- XDNA_ERR(xdna, "SVA bind device failed, ret %d", ret);
- goto failed;
- }
- client->pasid = iommu_sva_get_pasid(client->sva);
- if (client->pasid == IOMMU_PASID_INVALID) {
- XDNA_ERR(xdna, "SVA get pasid failed");
- ret = -ENODEV;
- goto unbind_sva;
- }
+ /* No need to fail open since user may use pa + carveout later. */
+ if (amdxdna_sva_init(client))
+ XDNA_WARN(xdna, "PASID not available for pid %d", client->pid);
}
- client->mm = current->mm;
mmgrab(client->mm);
init_srcu_struct(&client->hwctx_srcu);
xa_init_flags(&client->hwctx_xa, XA_FLAGS_ALLOC);
@@ -110,14 +132,6 @@ static int amdxdna_drm_open(struct drm_device *ddev, struct drm_file *filp)
XDNA_DBG(xdna, "pid %d opened", client->pid);
return 0;
-
-unbind_sva:
- if (!IS_ERR_OR_NULL(client->sva))
- iommu_sva_unbind_device(client->sva);
-failed:
- kfree(client);
-
- return ret;
}
static void amdxdna_client_cleanup(struct amdxdna_client *client)
@@ -131,11 +145,8 @@ static void amdxdna_client_cleanup(struct amdxdna_client *client)
drm_gem_object_put(to_gobj(client->dev_heap));
mutex_destroy(&client->mm_lock);
-
- if (!IS_ERR_OR_NULL(client->sva))
- iommu_sva_unbind_device(client->sva);
mmdrop(client->mm);
-
+ amdxdna_sva_fini(client);
kfree(client);
}
@@ -242,15 +253,17 @@ static void amdxdna_show_fdinfo(struct drm_printer *p, struct drm_file *filp)
/*
* Note for driver specific BO memory usage stat.
- * Total memory alloc = amdxdna-internal-alloc + amdxdna-external-alloc
+ * Total memory in use = amdxdna-internal-alloc + amdxdna-external-alloc, which
+ * includes both imported and created BOs. To avoid double counts, it includes
+ * HEAP BO, but not DEV BO. DEV BO is counted by amdxdna-heap-alloc.
*/
drm_fdinfo_print_size(p, drv_name, "heap", "alloc", heap_usage);
drm_fdinfo_print_size(p, drv_name, "internal", "alloc", internal_usage);
drm_fdinfo_print_size(p, drv_name, "external", "alloc", external_usage);
/*
* Note for DRM standard BO memory stat.
- * drm-total-memory counts both DEV BO and HEAP BO
- * drm-shared-memory counts BO imported
+ * drm-total-memory counts both DEV BO and HEAP BO. The DEV BO size is double counted.
+ * drm-shared-memory counts BO shared with other processes/devices.
*/
drm_show_memory_stats(p, filp);
}
@@ -299,25 +312,38 @@ amdxdna_get_dev_info(struct pci_dev *pdev)
return NULL;
}
+static void amdxdna_xdna_drm_release(struct drm_device *drm, void *res)
+{
+ struct amdxdna_dev *xdna = res;
+
+ amdxdna_carveout_fini(xdna);
+}
+
static int amdxdna_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct device *dev = &pdev->dev;
struct amdxdna_dev *xdna;
+ struct drm_device *ddev;
int ret;
xdna = devm_drm_dev_alloc(dev, &amdxdna_drm_drv, typeof(*xdna), ddev);
if (IS_ERR(xdna))
return PTR_ERR(xdna);
+ ddev = &xdna->ddev;
xdna->dev_info = amdxdna_get_dev_info(pdev);
if (!xdna->dev_info)
return -ENODEV;
- drmm_mutex_init(&xdna->ddev, &xdna->dev_lock);
+ drmm_mutex_init(ddev, &xdna->dev_lock);
init_rwsem(&xdna->notifier_lock);
INIT_LIST_HEAD(&xdna->client_list);
pci_set_drvdata(pdev, xdna);
+ ret = drmm_add_action(ddev, amdxdna_xdna_drm_release, xdna);
+ if (ret)
+ return ret;
+
if (IS_ENABLED(CONFIG_LOCKDEP)) {
fs_reclaim_acquire(GFP_KERNEL);
might_lock(&xdna->notifier_lock);
@@ -348,12 +374,13 @@ static int amdxdna_probe(struct pci_dev *pdev, const struct pci_device_id *id)
goto failed_dev_fini;
}
- ret = drm_dev_register(&xdna->ddev, 0);
+ ret = drm_dev_register(ddev, 0);
if (ret) {
XDNA_ERR(xdna, "DRM register failed, ret %d", ret);
goto failed_sysfs_fini;
}
+ amdxdna_debugfs_init(xdna);
return 0;
failed_sysfs_fini:
diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.h b/drivers/accel/amdxdna/amdxdna_pci_drv.h
index bdd0dc83f92e..b1548cf16f59 100644
--- a/drivers/accel/amdxdna/amdxdna_pci_drv.h
+++ b/drivers/accel/amdxdna/amdxdna_pci_drv.h
@@ -104,6 +104,8 @@ struct amdxdna_fw_ver {
u32 build;
};
+struct amdxdna_carveout;
+
struct amdxdna_dev {
struct drm_device ddev;
struct amdxdna_dev_hdl *dev_handle;
@@ -121,6 +123,8 @@ struct amdxdna_dev {
struct iova_domain iovad;
/* Accurate board name queried from firmware, or default_vbnv as fallback */
const char *vbnv;
+
+ struct amdxdna_carveout *carveout;
};
/*
@@ -172,11 +176,11 @@ void amdxdna_sysfs_fini(struct amdxdna_dev *xdna);
int amdxdna_iommu_init(struct amdxdna_dev *xdna);
void amdxdna_iommu_fini(struct amdxdna_dev *xdna);
-int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
-void amdxdna_iommu_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
void *amdxdna_iommu_alloc(struct amdxdna_dev *xdna, size_t size, dma_addr_t *dma_addr);
void amdxdna_iommu_free(struct amdxdna_dev *xdna, size_t size,
void *cpu_addr, dma_addr_t dma_addr);
+int amdxdna_dma_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
+void amdxdna_dma_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
static inline bool amdxdna_iova_on(struct amdxdna_dev *xdna)
{
--
2.34.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH V2] accel/amdxdna: Add carveout memory support for non-IOMMU systems
2026-04-27 17:09 [PATCH V2] accel/amdxdna: Add carveout memory support for non-IOMMU systems Lizhi Hou
@ 2026-05-04 19:08 ` Mario Limonciello
2026-05-05 15:32 ` Lizhi Hou
0 siblings, 1 reply; 3+ messages in thread
From: Mario Limonciello @ 2026-05-04 19:08 UTC (permalink / raw)
To: Lizhi Hou, ogabbay, quic_jhugo, dri-devel, maciej.falkowski
Cc: Max Zhen, linux-kernel, sonal.santan
On 4/27/26 12:09, Lizhi Hou wrote:
> From: Max Zhen <max.zhen@amd.com>
>
> Add support for allocating buffers from reserved carveout memory when
> IOMMU is not available. This is useful during debugging or bring-up.
>
> In this configuration, the device uses physical addresses and does
> not support scatter-gather lists, requiring physically contiguous
> buffers.
>
> Implement carveout-backed allocation and integrate it into buffer
> management to support operation in physical address mode.
>
> Signed-off-by: Max Zhen <max.zhen@amd.com>
> Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
> ---
> drivers/accel/amdxdna/Makefile | 2 +
> drivers/accel/amdxdna/amdxdna_cbuf.c | 280 ++++++++++++++++++++++++
> drivers/accel/amdxdna/amdxdna_cbuf.h | 18 ++
> drivers/accel/amdxdna/amdxdna_debugfs.c | 129 +++++++++++
> drivers/accel/amdxdna/amdxdna_debugfs.h | 18 ++
> drivers/accel/amdxdna/amdxdna_gem.c | 95 ++++++--
> drivers/accel/amdxdna/amdxdna_iommu.c | 77 ++++---
> drivers/accel/amdxdna/amdxdna_pci_drv.c | 89 +++++---
> drivers/accel/amdxdna/amdxdna_pci_drv.h | 8 +-
> 9 files changed, 636 insertions(+), 80 deletions(-)
> create mode 100644 drivers/accel/amdxdna/amdxdna_cbuf.c
> create mode 100644 drivers/accel/amdxdna/amdxdna_cbuf.h
> create mode 100644 drivers/accel/amdxdna/amdxdna_debugfs.c
> create mode 100644 drivers/accel/amdxdna/amdxdna_debugfs.h
>
> diff --git a/drivers/accel/amdxdna/Makefile b/drivers/accel/amdxdna/Makefile
> index 79369e497540..d7720c8c8a98 100644
> --- a/drivers/accel/amdxdna/Makefile
> +++ b/drivers/accel/amdxdna/Makefile
> @@ -12,6 +12,7 @@ amdxdna-y := \
> aie2_solver.o \
> aie4_message.o \
> aie4_pci.o \
> + amdxdna_cbuf.o \
> amdxdna_ctx.o \
> amdxdna_gem.o \
> amdxdna_iommu.o \
> @@ -28,4 +29,5 @@ amdxdna-y := \
> npu6_regs.o
>
> amdxdna-$(CONFIG_PCI_IOV) += aie4_sriov.o
> +amdxdna-$(CONFIG_DEBUG_FS) += amdxdna_debugfs.o
> obj-$(CONFIG_DRM_ACCEL_AMDXDNA) = amdxdna.o
> diff --git a/drivers/accel/amdxdna/amdxdna_cbuf.c b/drivers/accel/amdxdna/amdxdna_cbuf.c
> new file mode 100644
> index 000000000000..a504560aae98
> --- /dev/null
> +++ b/drivers/accel/amdxdna/amdxdna_cbuf.c
> @@ -0,0 +1,280 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
> + */
> +
> +#include <drm/drm_mm.h>
> +#include <drm/drm_prime.h>
> +
> +#include "amdxdna_cbuf.h"
> +#include "amdxdna_pci_drv.h"
> +
> +/*
> + * Carveout memory is a chunk of memory which is physically contiguous and
> + * is reserved during early boot time. There is only one chunk of such memory
> + * per device. Once available, all BOs accessible from device should be
> + * allocated from this memory. This is a platform debug/bringup feature.
> + */
> +struct amdxdna_carveout {
> + u64 addr;
> + u64 size;
> + struct drm_mm mm;
> + struct mutex lock; /* protect mm */
> +};
> +
> +bool amdxdna_use_carveout(struct amdxdna_dev *xdna)
> +{
> + return !!xdna->carveout;
> +}
> +
> +void amdxdna_get_carveout_conf(struct amdxdna_dev *xdna, u64 *addr, u64 *size)
> +{
> + if (amdxdna_use_carveout(xdna)) {
> + *addr = xdna->carveout->addr;
> + *size = xdna->carveout->size;
> + } else {
> + *addr = 0;
> + *size = 0;
> + }
> +}
> +
> +int amdxdna_carveout_init(struct amdxdna_dev *xdna, u64 carveout_addr, u64 carveout_size)
> +{
> + struct amdxdna_carveout *carveout;
> +
> + /* Only allow carveout memory to be set up once. */
> + if (amdxdna_use_carveout(xdna)) {
> + XDNA_ERR(xdna, "Carveout memory has already been set up.");
> + return -EBUSY;
> + }
> +
> + carveout = kzalloc_obj(*carveout);
> + if (!carveout)
> + return -ENOMEM;
> +
> + carveout->addr = carveout_addr;
> + carveout->size = carveout_size;
> + mutex_init(&carveout->lock);
> + drm_mm_init(&carveout->mm, carveout->addr, carveout->size);
> +
> + xdna->carveout = carveout;
> + XDNA_INFO(xdna, "Use carveout mem: 0x%llx@0x%llx\n", carveout->size, carveout->addr);
> + return 0;
> +}
> +
> +void amdxdna_carveout_fini(struct amdxdna_dev *xdna)
> +{
> + struct amdxdna_carveout *carveout = xdna->carveout;
> +
> + if (!amdxdna_use_carveout(xdna))
> + return;
> +
> + XDNA_INFO(xdna, "Cleanup carveout mem: 0x%llx@0x%llx\n", carveout->size, carveout->addr);
> + drm_mm_takedown(&carveout->mm);
> + mutex_destroy(&carveout->lock);
> + kfree(carveout);
> + xdna->carveout = NULL;
> +}
> +
> +struct amdxdna_cbuf_priv {
> + struct amdxdna_dev *xdna;
> + struct drm_mm_node node;
> +};
> +
> +static struct sg_table *amdxdna_cbuf_map(struct dma_buf_attachment *attach,
> + enum dma_data_direction direction)
> +{
> + struct amdxdna_cbuf_priv *cbuf = attach->dmabuf->priv;
> + struct device *dev = attach->dev;
> + struct scatterlist *sgl, *sg;
> + int ret, n_entries, i;
> + struct sg_table *sgt;
> + dma_addr_t dma_addr;
> + size_t dma_size;
> + size_t max_seg;
> +
> + sgt = kzalloc_obj(*sgt);
> + if (!sgt)
> + return ERR_PTR(-ENOMEM);
> +
> + max_seg = min_t(size_t, UINT_MAX, dma_max_mapping_size(dev));
> + n_entries = (cbuf->node.size + max_seg - 1) / max_seg;
> + sgl = kzalloc_objs(*sg, n_entries);
> + if (!sgl) {
> + ret = -ENOMEM;
> + goto free_sgt;
> + }
> + sg_init_table(sgl, n_entries);
> + sgt->orig_nents = n_entries;
> + sgt->nents = n_entries;
> + sgt->sgl = sgl;
> +
> + dma_size = cbuf->node.size;
> + dma_addr = dma_map_resource(dev, cbuf->node.start, dma_size,
> + direction, DMA_ATTR_SKIP_CPU_SYNC);
> + ret = dma_mapping_error(dev, dma_addr);
> + if (ret) {
> + pr_err("Failed to dma_map_resource carveout dma buf, ret %d\n", ret);
> + goto free_sgl;
> + }
> +
> + for_each_sgtable_dma_sg(sgt, sg, i) {
> + size_t len = min_t(size_t, max_seg, dma_size);
> +
> + sg_dma_address(sg) = dma_addr;
> + sg_dma_len(sg) = len;
> + dma_addr += len;
> + dma_size -= len;
> + }
> +
> + return sgt;
> +
> +free_sgl:
> + kfree(sgl);
> +free_sgt:
> + kfree(sgt);
> + return ERR_PTR(ret);
> +}
> +
> +static void amdxdna_cbuf_unmap(struct dma_buf_attachment *attach,
> + struct sg_table *sgt,
> + enum dma_data_direction direction)
> +{
> + dma_unmap_resource(attach->dev, sg_dma_address(sgt->sgl),
> + drm_prime_get_contiguous_size(sgt), direction,
> + DMA_ATTR_SKIP_CPU_SYNC);
> + sg_free_table(sgt);
> + kfree(sgt);
> +}
> +
> +static void amdxdna_cbuf_release(struct dma_buf *dbuf)
> +{
> + struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
> + struct amdxdna_carveout *carveout;
> +
> + carveout = cbuf->xdna->carveout;
> + mutex_lock(&carveout->lock);
> + drm_mm_remove_node(&cbuf->node);
> + mutex_unlock(&carveout->lock);
> +
> + kfree(cbuf);
> +}
> +
> +static vm_fault_t amdxdna_cbuf_vm_fault(struct vm_fault *vmf)
> +{
> + struct vm_area_struct *vma = vmf->vma;
> + struct amdxdna_cbuf_priv *cbuf;
> + unsigned long pfn;
> + pgoff_t pgoff;
> +
> + cbuf = vma->vm_private_data;
> + pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
> + pfn = (cbuf->node.start >> PAGE_SHIFT) + pgoff;
> +
> + return vmf_insert_pfn(vma, vmf->address, pfn);
> +}
> +
> +static const struct vm_operations_struct amdxdna_cbuf_vm_ops = {
> + .fault = amdxdna_cbuf_vm_fault,
> +};
> +
> +static int amdxdna_cbuf_mmap(struct dma_buf *dbuf, struct vm_area_struct *vma)
> +{
> + struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
> +
> + vma->vm_ops = &amdxdna_cbuf_vm_ops;
> + vma->vm_private_data = cbuf;
> + vm_flags_set(vma, VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP);
> +
> + return 0;
> +}
> +
> +static int amdxdna_cbuf_vmap(struct dma_buf *dbuf, struct iosys_map *map)
> +{
> + struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
> + void *kva;
> +
> + kva = memremap(cbuf->node.start, cbuf->node.size, MEMREMAP_WB);
> + if (!kva) {
> + pr_err("Failed to vmap carveout dma buf\n");
> + return -ENOMEM;
> + }
> +
> + iosys_map_set_vaddr(map, kva);
> + return 0;
> +}
> +
> +static void amdxdna_cbuf_vunmap(struct dma_buf *dbuf, struct iosys_map *map)
> +{
> + memunmap(map->vaddr);
> +}
> +
> +static const struct dma_buf_ops amdxdna_cbuf_dmabuf_ops = {
> + .map_dma_buf = amdxdna_cbuf_map,
> + .unmap_dma_buf = amdxdna_cbuf_unmap,
> + .release = amdxdna_cbuf_release,
> + .mmap = amdxdna_cbuf_mmap,
> + .vmap = amdxdna_cbuf_vmap,
> + .vunmap = amdxdna_cbuf_vunmap,
> +};
> +
> +static int amdxdna_cbuf_clear(struct dma_buf *dbuf)
> +{
> + struct iosys_map vmap = IOSYS_MAP_INIT_VADDR(NULL);
> +
> + dma_buf_vmap(dbuf, &vmap);
> + if (!vmap.vaddr)
> + return -EFAULT;
> +
> + memset(vmap.vaddr, 0, dbuf->size);
> + dma_buf_vunmap(dbuf, &vmap);
> +
> + return 0;
> +}
> +
> +struct dma_buf *amdxdna_get_cbuf(struct drm_device *dev, size_t size, u64 alignment)
> +{
> + struct amdxdna_dev *xdna = to_xdna_dev(dev);
> + DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
> + struct amdxdna_carveout *carveout;
> + struct amdxdna_cbuf_priv *cbuf;
> + struct dma_buf *dbuf;
> + int ret;
> +
> + cbuf = kzalloc_obj(*cbuf);
> + if (!cbuf)
> + return ERR_PTR(-ENOMEM);
> + cbuf->xdna = xdna;
> +
> + carveout = xdna->carveout;
> + mutex_lock(&carveout->lock);
> + ret = drm_mm_insert_node_generic(&carveout->mm, &cbuf->node, size,
> + alignment, 0, DRM_MM_INSERT_BEST);
> + mutex_unlock(&carveout->lock);
> + if (ret)
> + goto free_cbuf;
> +
> + exp_info.size = size;
> + exp_info.ops = &amdxdna_cbuf_dmabuf_ops;
> + exp_info.priv = cbuf;
> + exp_info.flags = O_RDWR;
> + dbuf = dma_buf_export(&exp_info);
> + if (IS_ERR(dbuf)) {
> + ret = PTR_ERR(dbuf);
> + goto remove_node;
> + }
> +
> + ret = amdxdna_cbuf_clear(dbuf);
> + if (ret) {
> + dma_buf_put(dbuf);
> + goto out;
> + }
> + return dbuf;
> +
> +remove_node:
> + drm_mm_remove_node(&cbuf->node);
> +free_cbuf:
> + kfree(cbuf);
> +out:
> + return ERR_PTR(ret);
> +}
> diff --git a/drivers/accel/amdxdna/amdxdna_cbuf.h b/drivers/accel/amdxdna/amdxdna_cbuf.h
> new file mode 100644
> index 000000000000..8e89336ffd50
> --- /dev/null
> +++ b/drivers/accel/amdxdna/amdxdna_cbuf.h
> @@ -0,0 +1,18 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
> + */
> +#ifndef _AMDXDNA_CBUF_H_
> +#define _AMDXDNA_CBUF_H_
> +
> +#include "amdxdna_pci_drv.h"
> +#include <drm/drm_device.h>
> +#include <linux/dma-buf.h>
> +
> +bool amdxdna_use_carveout(struct amdxdna_dev *xdna);
> +int amdxdna_carveout_init(struct amdxdna_dev *xdna, u64 carveout_addr, u64 carveout_size);
> +void amdxdna_carveout_fini(struct amdxdna_dev *xdna);
> +void amdxdna_get_carveout_conf(struct amdxdna_dev *xdna, u64 *addr, u64 *size);
> +struct dma_buf *amdxdna_get_cbuf(struct drm_device *dev, size_t size, u64 alignment);
> +
> +#endif
> diff --git a/drivers/accel/amdxdna/amdxdna_debugfs.c b/drivers/accel/amdxdna/amdxdna_debugfs.c
> new file mode 100644
> index 000000000000..a6ec17c63629
> --- /dev/null
> +++ b/drivers/accel/amdxdna/amdxdna_debugfs.c
> @@ -0,0 +1,129 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
> + */
> +
> +#include "amdxdna_cbuf.h"
> +#include "amdxdna_debugfs.h"
> +
> +#include <drm/drm_file.h>
> +#include <linux/debugfs.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/seq_file.h>
> +#include <linux/string.h>
> +#include <linux/uaccess.h>
> +
> +#define _DBGFS_FOPS(_open, _release, _write) \
> +{ \
> + .owner = THIS_MODULE, \
> + .open = _open, \
> + .read = seq_read, \
> + .llseek = seq_lseek, \
> + .release = _release, \
> + .write = _write, \
> +}
> +
> +#define AMDXDNA_DBGFS_FOPS(_name, _show, _write) \
> + static int amdxdna_dbgfs_##_name##_open(struct inode *inode, struct file *file) \
> + { \
> + return single_open(file, _show, inode->i_private); \
> + } \
> + static int amdxdna_dbgfs_##_name##_release(struct inode *inode, struct file *file) \
> + { \
> + return single_release(inode, file); \
> + } \
> + static const struct file_operations amdxdna_fops_##_name = \
> + _DBGFS_FOPS(amdxdna_dbgfs_##_name##_open, amdxdna_dbgfs_##_name##_release, _write)
> +
> +#define AMDXDNA_DBGFS_FILE(_name, _mode) { #_name, &amdxdna_fops_##_name, _mode }
> +
> +#define file_to_xdna(file) (((struct seq_file *)(file)->private_data)->private)
> +
> +static ssize_t amdxdna_carveout_write(struct file *file, const char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + struct amdxdna_dev *xdna = file_to_xdna(file);
> + char kbuf[128];
> + u64 size, addr;
> + char *sep;
> + int ret;
> +
> + if (count == 0 || count >= sizeof(kbuf))
> + return -EINVAL;
> +
> + if (copy_from_user(kbuf, buf, count))
> + return -EFAULT;
> + kbuf[count] = '\0';
> + strim(kbuf);
> + XDNA_DBG(xdna, "Trying to set carveout to %s", kbuf);
> +
> + sep = strchr(kbuf, '@');
> + if (!sep)
> + return -EINVAL;
> + *sep = '\0';
> + sep++;
> +
> + ret = kstrtou64(kbuf, 0, &size);
> + if (ret)
> + return ret;
> +
> + ret = kstrtou64(sep, 0, &addr);
> + if (ret)
> + return ret;
> +
> + /* Sanity check the addr and size. */
> + if (!size)
> + return -EINVAL;
> + if (!IS_ALIGNED(addr, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE))
> + return -EINVAL;
> +
> + guard(mutex)(&xdna->dev_lock);
> +
> + ret = amdxdna_carveout_init(xdna, addr, size);
> + if (ret)
> + return ret;
> +
> + return count;
> +}
> +
> +static int amdxdna_carveout_show(struct seq_file *m, void *unused)
> +{
> + struct amdxdna_dev *xdna = m->private;
> + u64 addr, size;
> +
> + guard(mutex)(&xdna->dev_lock);
> + amdxdna_get_carveout_conf(xdna, &addr, &size);
> + seq_printf(m, "0x%llx@0x%llx\n", size, addr);
> + return 0;
> +}
> +
> +/*
> + * Input/output format: <carveout_size>@<carveout_address>
> + */
> +AMDXDNA_DBGFS_FOPS(carveout, amdxdna_carveout_show, amdxdna_carveout_write);
> +
> +static const struct {
> + const char *name;
> + const struct file_operations *fops;
> + umode_t mode;
> +} amdxdna_dbgfs_files[] = {
> + AMDXDNA_DBGFS_FILE(carveout, 0600),
> +};
> +
> +void amdxdna_debugfs_init(struct amdxdna_dev *xdna)
> +{
> + struct drm_minor *minor = xdna->ddev.accel;
> + int i;
> +
> + /*
> + * It should be okay that debugfs fails to init.
> + * We rely on DRM framework to finish debugfs.
> + */
> + for (i = 0; i < ARRAY_SIZE(amdxdna_dbgfs_files); i++) {
> + debugfs_create_file(amdxdna_dbgfs_files[i].name,
> + amdxdna_dbgfs_files[i].mode,
> + minor->debugfs_root,
> + xdna,
> + amdxdna_dbgfs_files[i].fops);
> + }
> +}
> diff --git a/drivers/accel/amdxdna/amdxdna_debugfs.h b/drivers/accel/amdxdna/amdxdna_debugfs.h
> new file mode 100644
> index 000000000000..2abb45de3f7e
> --- /dev/null
> +++ b/drivers/accel/amdxdna/amdxdna_debugfs.h
> @@ -0,0 +1,18 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
> + */
> +#ifndef _AMDXDNA_DEBUGFS_H_
> +#define _AMDXDNA_DEBUGFS_H_
> +
> +#include "amdxdna_pci_drv.h"
> +
> +#if defined(CONFIG_DEBUG_FS)
> +void amdxdna_debugfs_init(struct amdxdna_dev *xdna);
> +#else
> +static inline void amdxdna_debugfs_init(struct amdxdna_dev *xdna)
> +{
> +}
> +#endif /* CONFIG_DEBUG_FS */
> +
> +#endif
> diff --git a/drivers/accel/amdxdna/amdxdna_gem.c b/drivers/accel/amdxdna/amdxdna_gem.c
> index 238ee244d4a6..ebfc472aa9e7 100644
> --- a/drivers/accel/amdxdna/amdxdna_gem.c
> +++ b/drivers/accel/amdxdna/amdxdna_gem.c
> @@ -16,6 +16,7 @@
> #include <linux/pagemap.h>
> #include <linux/vmalloc.h>
>
> +#include "amdxdna_cbuf.h"
> #include "amdxdna_ctx.h"
> #include "amdxdna_gem.h"
> #include "amdxdna_pci_drv.h"
> @@ -516,10 +517,6 @@ static void amdxdna_imported_obj_free(struct amdxdna_gem_obj *abo)
> static inline bool
> amdxdna_gem_skip_bo_usage(struct amdxdna_gem_obj *abo)
> {
> - /* Do not count imported BOs since the buffer is not allocated by us. */
> - if (is_import_bo(abo))
> - return true;
> -
> /* Already counted as part of HEAP BO */
> if (abo->type == AMDXDNA_BO_DEV)
> return true;
> @@ -571,9 +568,7 @@ static void amdxdna_gem_obj_free(struct drm_gem_object *gobj)
> if (abo->type == AMDXDNA_BO_DEV_HEAP)
> drm_mm_takedown(&abo->mm);
>
> - if (amdxdna_iova_on(xdna))
> - amdxdna_iommu_unmap_bo(xdna, abo);
> -
> + amdxdna_dma_unmap_bo(xdna, abo);
> amdxdna_gem_vunmap(abo);
> mutex_destroy(&abo->lock);
>
> @@ -591,18 +586,20 @@ static int amdxdna_gem_obj_open(struct drm_gem_object *gobj, struct drm_file *fi
>
> guard(mutex)(&abo->lock);
> abo->open_ref++;
> + if (abo->open_ref > 1)
> + return 0;
>
> - if (abo->open_ref == 1) {
> - /* Attached to the client when first opened by it. */
> - abo->client = filp->driver_priv;
> - amdxdna_gem_add_bo_usage(abo);
> - }
> - if (amdxdna_iova_on(xdna)) {
> - ret = amdxdna_iommu_map_bo(xdna, abo);
> + /* Attached to the client when first opened by it. */
> + abo->client = filp->driver_priv;
> +
> + /* No need to set up dma addr mapping in PASID mode. */
> + if (!amdxdna_pasid_on(abo->client)) {
> + ret = amdxdna_dma_map_bo(xdna, abo);
> if (ret)
> return ret;
> }
>
> + amdxdna_gem_add_bo_usage(abo);
> return 0;
> }
>
> @@ -620,6 +617,39 @@ static void amdxdna_gem_obj_close(struct drm_gem_object *gobj, struct drm_file *
> }
> }
>
> +static int amdxdna_gem_obj_vmap(struct drm_gem_object *obj, struct iosys_map *map)
> +{
> + struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
> + int ret;
> +
> + iosys_map_clear(map);
> +
> + dma_resv_assert_held(obj->resv);
> +
> + if (is_import_bo(abo))
> + ret = dma_buf_vmap(abo->dma_buf, map);
> + else
> + ret = drm_gem_shmem_object_vmap(obj, map);
> + if (ret)
> + return ret;
> + if (!map->vaddr)
> + return -ENOMEM;
> +
> + return 0;
> +}
> +
> +static void amdxdna_gem_obj_vunmap(struct drm_gem_object *obj, struct iosys_map *map)
> +{
> + struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
> +
> + dma_resv_assert_held(obj->resv);
> +
> + if (is_import_bo(abo))
> + dma_buf_vunmap(abo->dma_buf, map);
> + else
> + drm_gem_shmem_object_vunmap(obj, map);
> +}
> +
> static int amdxdna_gem_dev_obj_vmap(struct drm_gem_object *obj, struct iosys_map *map)
> {
> struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
> @@ -645,8 +675,8 @@ static const struct drm_gem_object_funcs amdxdna_gem_shmem_funcs = {
> .pin = drm_gem_shmem_object_pin,
> .unpin = drm_gem_shmem_object_unpin,
> .get_sg_table = drm_gem_shmem_object_get_sg_table,
> - .vmap = drm_gem_shmem_object_vmap,
> - .vunmap = drm_gem_shmem_object_vunmap,
> + .vmap = amdxdna_gem_obj_vmap,
> + .vunmap = amdxdna_gem_obj_vunmap,
> .mmap = amdxdna_gem_obj_mmap,
> .vm_ops = &drm_gem_shmem_vm_ops,
> .export = amdxdna_gem_prime_export,
> @@ -714,6 +744,36 @@ amdxdna_gem_create_ubuf_object(struct drm_device *dev, struct amdxdna_drm_create
> return to_xdna_obj(gobj);
> }
>
> +static struct amdxdna_gem_obj *
> +amdxdna_gem_create_cbuf_object(struct drm_device *dev, struct amdxdna_drm_create_bo *args)
> +{
> + struct amdxdna_dev *xdna = to_xdna_dev(dev);
> + size_t size = PAGE_ALIGN(args->size);
> + struct drm_gem_object *gobj;
> + struct amdxdna_gem_obj *ret;
> + struct dma_buf *dma_buf;
> + u64 align;
> +
> + if (!size) {
> + XDNA_ERR(xdna, "Invalid BO size 0x%llx", args->size);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + align = (args->type == AMDXDNA_BO_DEV_HEAP) ? xdna->dev_info->dev_mem_size : 0;
> + dma_buf = amdxdna_get_cbuf(dev, size, align);
> + if (IS_ERR(dma_buf))
> + return ERR_CAST(dma_buf);
> +
> + gobj = amdxdna_gem_prime_import(dev, dma_buf);
> + if (IS_ERR(gobj))
> + ret = ERR_CAST(gobj);
> + else
> + ret = to_xdna_obj(gobj);
> +
> + dma_buf_put(dma_buf);
> + return ret;
> +}
> +
> struct drm_gem_object *
> amdxdna_gem_prime_import(struct drm_device *dev, struct dma_buf *dma_buf)
> {
> @@ -769,6 +829,8 @@ amdxdna_drm_create_share_bo(struct drm_device *dev,
>
> if (args->vaddr)
> abo = amdxdna_gem_create_ubuf_object(dev, args);
> + else if (amdxdna_use_carveout(to_xdna_dev(dev)))
> + abo = amdxdna_gem_create_cbuf_object(dev, args);
> else
> abo = amdxdna_gem_create_shmem_object(dev, args);
> if (IS_ERR(abo))
> @@ -884,7 +946,6 @@ int amdxdna_drm_create_bo_ioctl(struct drm_device *dev, void *data, struct drm_f
> args->type, args->vaddr, args->size, args->flags);
> switch (args->type) {
> case AMDXDNA_BO_CMD:
> - fallthrough;
> case AMDXDNA_BO_SHARE:
> abo = amdxdna_drm_create_share_bo(dev, args, filp);
> break;
> diff --git a/drivers/accel/amdxdna/amdxdna_iommu.c b/drivers/accel/amdxdna/amdxdna_iommu.c
> index 5a9f06183487..eff00131d0f8 100644
> --- a/drivers/accel/amdxdna/amdxdna_iommu.c
> +++ b/drivers/accel/amdxdna/amdxdna_iommu.c
> @@ -35,14 +35,15 @@ static struct iova *amdxdna_iommu_alloc_iova(struct amdxdna_dev *xdna,
> return iova;
> }
>
> -int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
> +int amdxdna_dma_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
> {
> + unsigned long contig_sz;
> struct sg_table *sgt;
> dma_addr_t dma_addr;
> struct iova *iova;
> ssize_t size;
>
> - if (abo->type != AMDXDNA_BO_DEV_HEAP && abo->type != AMDXDNA_BO_SHMEM)
> + if (abo->type != AMDXDNA_BO_DEV_HEAP && abo->type != AMDXDNA_BO_SHARE)
> return 0;
>
> sgt = drm_gem_shmem_get_pages_sgt(&abo->base);
> @@ -51,47 +52,63 @@ int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
> return PTR_ERR(sgt);
> }
>
> - if (!sgt->orig_nents || !sg_page(sgt->sgl)) {
> - XDNA_ERR(xdna, "sgl is zero length or not page backed");
> + if (!sgt->orig_nents) {
> + XDNA_ERR(xdna, "sgl is zero length");
> return -EOPNOTSUPP;
> }
>
> - iova = amdxdna_iommu_alloc_iova(xdna, abo->mem.size, &dma_addr,
> - (abo->type == AMDXDNA_BO_DEV_HEAP));
> - if (IS_ERR(iova)) {
> - XDNA_ERR(xdna, "Alloc iova failed, ret %ld", PTR_ERR(iova));
> - return PTR_ERR(iova);
> + if (amdxdna_iova_on(xdna)) {
> + if (!sg_page(sgt->sgl)) {
> + XDNA_ERR(xdna, "sgl is not page backed");
> + return -EOPNOTSUPP;
> + }
> +
> + iova = amdxdna_iommu_alloc_iova(xdna, abo->mem.size, &dma_addr,
> + (abo->type == AMDXDNA_BO_DEV_HEAP));
> + if (IS_ERR(iova)) {
> + XDNA_ERR(xdna, "Alloc iova failed, ret %ld", PTR_ERR(iova));
> + return PTR_ERR(iova);
> + }
> +
> + size = iommu_map_sgtable(xdna->domain, dma_addr, sgt,
> + IOMMU_READ | IOMMU_WRITE);
> + if (size < 0) {
> + XDNA_ERR(xdna, "iommu_map_sgtable failed: %zd", size);
> + __free_iova(&xdna->iovad, iova);
> + return size;
> + }
> + if (size < abo->mem.size) {
> + iommu_unmap(xdna->domain, dma_addr, size);
> + __free_iova(&xdna->iovad, iova);
> + return -ENXIO;
> + }
> + abo->mem.dma_addr = dma_addr;
> + } else {
> + /* Device doesn't support scatter/gather list, fail non-contiguous mapping. */
> + contig_sz = drm_prime_get_contiguous_size(sgt);
> + if (contig_sz < abo->mem.size) {
> + XDNA_ERR(xdna,
> + "noncontiguous dma addr, contig size:%ld, expected size:%ld",
> + contig_sz, abo->mem.size);
> + return -EINVAL;
> + }
> + abo->mem.dma_addr = sg_dma_address(sgt->sgl);
> }
> -
> - size = iommu_map_sgtable(xdna->domain, dma_addr, sgt,
> - IOMMU_READ | IOMMU_WRITE);
> - if (size < 0) {
> - XDNA_ERR(xdna, "iommu_map_sgtable failed: %zd", size);
> - __free_iova(&xdna->iovad, iova);
> - return size;
> - }
> -
> - if (size < abo->mem.size) {
> - iommu_unmap(xdna->domain, dma_addr, size);
> - __free_iova(&xdna->iovad, iova);
> - return -ENXIO;
> - }
> -
> - abo->mem.dma_addr = dma_addr;
> -
> return 0;
> }
>
> -void amdxdna_iommu_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
> +void amdxdna_dma_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo)
> {
> size_t size;
>
> if (abo->mem.dma_addr == AMDXDNA_INVALID_ADDR)
> return;
>
> - size = iova_align(&xdna->iovad, abo->mem.size);
> - iommu_unmap(xdna->domain, abo->mem.dma_addr, size);
> - free_iova(&xdna->iovad, iova_pfn(&xdna->iovad, abo->mem.dma_addr));
> + if (amdxdna_iova_on(xdna)) {
> + size = iova_align(&xdna->iovad, abo->mem.size);
> + iommu_unmap(xdna->domain, abo->mem.dma_addr, size);
> + free_iova(&xdna->iovad, iova_pfn(&xdna->iovad, abo->mem.dma_addr));
> + }
> abo->mem.dma_addr = AMDXDNA_INVALID_ADDR;
> }
>
> diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.c b/drivers/accel/amdxdna/amdxdna_pci_drv.c
> index 21eddfc538d0..1b08a08343cf 100644
> --- a/drivers/accel/amdxdna/amdxdna_pci_drv.c
> +++ b/drivers/accel/amdxdna/amdxdna_pci_drv.c
> @@ -14,7 +14,9 @@
> #include <linux/iommu.h>
> #include <linux/pci.h>
>
> +#include "amdxdna_cbuf.h"
> #include "amdxdna_ctx.h"
> +#include "amdxdna_debugfs.h"
> #include "amdxdna_gem.h"
> #include "amdxdna_pci_drv.h"
> #include "amdxdna_pm.h"
> @@ -67,11 +69,40 @@ static const struct amdxdna_device_id amdxdna_ids[] = {
> {0}
> };
>
> +static int amdxdna_sva_init(struct amdxdna_client *client)
> +{
> + struct amdxdna_dev *xdna = client->xdna;
> +
> + client->sva = iommu_sva_bind_device(xdna->ddev.dev, client->mm);
> + if (IS_ERR(client->sva)) {
> + XDNA_ERR(xdna, "SVA bind device failed, ret %ld", PTR_ERR(client->sva));
> + return PTR_ERR(client->sva);
> + }
> +
> + client->pasid = iommu_sva_get_pasid(client->sva);
> + if (client->pasid == IOMMU_PASID_INVALID) {
> + iommu_sva_unbind_device(client->sva);
> + XDNA_ERR(xdna, "SVA get pasid failed");
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> +static void amdxdna_sva_fini(struct amdxdna_client *client)
> +{
> + if (IS_ERR_OR_NULL(client->sva))
> + return;
> +
> + iommu_sva_unbind_device(client->sva);
> + client->sva = NULL;
> + client->pasid = IOMMU_PASID_INVALID;
> +}
> +
> static int amdxdna_drm_open(struct drm_device *ddev, struct drm_file *filp)
> {
> struct amdxdna_dev *xdna = to_xdna_dev(ddev);
> struct amdxdna_client *client;
> - int ret;
>
> client = kzalloc_obj(*client);
> if (!client)
> @@ -80,22 +111,13 @@ static int amdxdna_drm_open(struct drm_device *ddev, struct drm_file *filp)
> client->pid = pid_nr(rcu_access_pointer(filp->pid));
> client->xdna = xdna;
> client->pasid = IOMMU_PASID_INVALID;
> + client->mm = current->mm;
>
> if (!amdxdna_iova_on(xdna)) {
> - client->sva = iommu_sva_bind_device(xdna->ddev.dev, current->mm);
> - if (IS_ERR(client->sva)) {
> - ret = PTR_ERR(client->sva);
> - XDNA_ERR(xdna, "SVA bind device failed, ret %d", ret);
> - goto failed;
> - }
> - client->pasid = iommu_sva_get_pasid(client->sva);
> - if (client->pasid == IOMMU_PASID_INVALID) {
> - XDNA_ERR(xdna, "SVA get pasid failed");
> - ret = -ENODEV;
> - goto unbind_sva;
> - }
> + /* No need to fail open since user may use pa + carveout later. */
> + if (amdxdna_sva_init(client))
> + XDNA_WARN(xdna, "PASID not available for pid %d", client->pid);
> }
> - client->mm = current->mm;
> mmgrab(client->mm);
> init_srcu_struct(&client->hwctx_srcu);
> xa_init_flags(&client->hwctx_xa, XA_FLAGS_ALLOC);
> @@ -110,14 +132,6 @@ static int amdxdna_drm_open(struct drm_device *ddev, struct drm_file *filp)
>
> XDNA_DBG(xdna, "pid %d opened", client->pid);
> return 0;
> -
> -unbind_sva:
> - if (!IS_ERR_OR_NULL(client->sva))
> - iommu_sva_unbind_device(client->sva);
> -failed:
> - kfree(client);
> -
> - return ret;
> }
>
> static void amdxdna_client_cleanup(struct amdxdna_client *client)
> @@ -131,11 +145,8 @@ static void amdxdna_client_cleanup(struct amdxdna_client *client)
> drm_gem_object_put(to_gobj(client->dev_heap));
>
> mutex_destroy(&client->mm_lock);
> -
> - if (!IS_ERR_OR_NULL(client->sva))
> - iommu_sva_unbind_device(client->sva);
> mmdrop(client->mm);
> -
> + amdxdna_sva_fini(client);
> kfree(client);
> }
>
> @@ -242,15 +253,17 @@ static void amdxdna_show_fdinfo(struct drm_printer *p, struct drm_file *filp)
>
> /*
> * Note for driver specific BO memory usage stat.
> - * Total memory alloc = amdxdna-internal-alloc + amdxdna-external-alloc
> + * Total memory in use = amdxdna-internal-alloc + amdxdna-external-alloc, which
> + * includes both imported and created BOs. To avoid double counts, it includes
> + * HEAP BO, but not DEV BO. DEV BO is counted by amdxdna-heap-alloc.
> */
> drm_fdinfo_print_size(p, drv_name, "heap", "alloc", heap_usage);
> drm_fdinfo_print_size(p, drv_name, "internal", "alloc", internal_usage);
> drm_fdinfo_print_size(p, drv_name, "external", "alloc", external_usage);
> /*
> * Note for DRM standard BO memory stat.
> - * drm-total-memory counts both DEV BO and HEAP BO
> - * drm-shared-memory counts BO imported
> + * drm-total-memory counts both DEV BO and HEAP BO. The DEV BO size is double counted.
> + * drm-shared-memory counts BO shared with other processes/devices.
> */
> drm_show_memory_stats(p, filp);
> }
> @@ -299,25 +312,38 @@ amdxdna_get_dev_info(struct pci_dev *pdev)
> return NULL;
> }
>
> +static void amdxdna_xdna_drm_release(struct drm_device *drm, void *res)
> +{
> + struct amdxdna_dev *xdna = res;
> +
> + amdxdna_carveout_fini(xdna);
> +}
> +
> static int amdxdna_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> {
> struct device *dev = &pdev->dev;
> struct amdxdna_dev *xdna;
> + struct drm_device *ddev;
> int ret;
>
> xdna = devm_drm_dev_alloc(dev, &amdxdna_drm_drv, typeof(*xdna), ddev);
> if (IS_ERR(xdna))
> return PTR_ERR(xdna);
> + ddev = &xdna->ddev;
>
> xdna->dev_info = amdxdna_get_dev_info(pdev);
> if (!xdna->dev_info)
> return -ENODEV;
>
> - drmm_mutex_init(&xdna->ddev, &xdna->dev_lock);
> + drmm_mutex_init(ddev, &xdna->dev_lock);
> init_rwsem(&xdna->notifier_lock);
> INIT_LIST_HEAD(&xdna->client_list);
> pci_set_drvdata(pdev, xdna);
>
> + ret = drmm_add_action(ddev, amdxdna_xdna_drm_release, xdna);
> + if (ret)
> + return ret;
> +
> if (IS_ENABLED(CONFIG_LOCKDEP)) {
> fs_reclaim_acquire(GFP_KERNEL);
> might_lock(&xdna->notifier_lock);
> @@ -348,12 +374,13 @@ static int amdxdna_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> goto failed_dev_fini;
> }
>
> - ret = drm_dev_register(&xdna->ddev, 0);
> + ret = drm_dev_register(ddev, 0);
> if (ret) {
> XDNA_ERR(xdna, "DRM register failed, ret %d", ret);
> goto failed_sysfs_fini;
> }
>
> + amdxdna_debugfs_init(xdna);
> return 0;
>
> failed_sysfs_fini:
> diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.h b/drivers/accel/amdxdna/amdxdna_pci_drv.h
> index bdd0dc83f92e..b1548cf16f59 100644
> --- a/drivers/accel/amdxdna/amdxdna_pci_drv.h
> +++ b/drivers/accel/amdxdna/amdxdna_pci_drv.h
> @@ -104,6 +104,8 @@ struct amdxdna_fw_ver {
> u32 build;
> };
>
> +struct amdxdna_carveout;
> +
> struct amdxdna_dev {
> struct drm_device ddev;
> struct amdxdna_dev_hdl *dev_handle;
> @@ -121,6 +123,8 @@ struct amdxdna_dev {
> struct iova_domain iovad;
> /* Accurate board name queried from firmware, or default_vbnv as fallback */
> const char *vbnv;
> +
> + struct amdxdna_carveout *carveout;
> };
>
> /*
> @@ -172,11 +176,11 @@ void amdxdna_sysfs_fini(struct amdxdna_dev *xdna);
>
> int amdxdna_iommu_init(struct amdxdna_dev *xdna);
> void amdxdna_iommu_fini(struct amdxdna_dev *xdna);
> -int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
> -void amdxdna_iommu_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
> void *amdxdna_iommu_alloc(struct amdxdna_dev *xdna, size_t size, dma_addr_t *dma_addr);
> void amdxdna_iommu_free(struct amdxdna_dev *xdna, size_t size,
> void *cpu_addr, dma_addr_t dma_addr);
> +int amdxdna_dma_map_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
> +void amdxdna_dma_unmap_bo(struct amdxdna_dev *xdna, struct amdxdna_gem_obj *abo);
>
> static inline bool amdxdna_iova_on(struct amdxdna_dev *xdna)
> {
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH V2] accel/amdxdna: Add carveout memory support for non-IOMMU systems
2026-05-04 19:08 ` Mario Limonciello
@ 2026-05-05 15:32 ` Lizhi Hou
0 siblings, 0 replies; 3+ messages in thread
From: Lizhi Hou @ 2026-05-05 15:32 UTC (permalink / raw)
To: Mario Limonciello, ogabbay, quic_jhugo, dri-devel,
maciej.falkowski
Cc: Max Zhen, linux-kernel, sonal.santan
Applied to drm-misc-next
On 5/4/26 12:08, Mario Limonciello wrote:
>
>
> On 4/27/26 12:09, Lizhi Hou wrote:
>> From: Max Zhen <max.zhen@amd.com>
>>
>> Add support for allocating buffers from reserved carveout memory when
>> IOMMU is not available. This is useful during debugging or bring-up.
>>
>> In this configuration, the device uses physical addresses and does
>> not support scatter-gather lists, requiring physically contiguous
>> buffers.
>>
>> Implement carveout-backed allocation and integrate it into buffer
>> management to support operation in physical address mode.
>>
>> Signed-off-by: Max Zhen <max.zhen@amd.com>
>> Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
> Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
>> ---
>> drivers/accel/amdxdna/Makefile | 2 +
>> drivers/accel/amdxdna/amdxdna_cbuf.c | 280 ++++++++++++++++++++++++
>> drivers/accel/amdxdna/amdxdna_cbuf.h | 18 ++
>> drivers/accel/amdxdna/amdxdna_debugfs.c | 129 +++++++++++
>> drivers/accel/amdxdna/amdxdna_debugfs.h | 18 ++
>> drivers/accel/amdxdna/amdxdna_gem.c | 95 ++++++--
>> drivers/accel/amdxdna/amdxdna_iommu.c | 77 ++++---
>> drivers/accel/amdxdna/amdxdna_pci_drv.c | 89 +++++---
>> drivers/accel/amdxdna/amdxdna_pci_drv.h | 8 +-
>> 9 files changed, 636 insertions(+), 80 deletions(-)
>> create mode 100644 drivers/accel/amdxdna/amdxdna_cbuf.c
>> create mode 100644 drivers/accel/amdxdna/amdxdna_cbuf.h
>> create mode 100644 drivers/accel/amdxdna/amdxdna_debugfs.c
>> create mode 100644 drivers/accel/amdxdna/amdxdna_debugfs.h
>>
>> diff --git a/drivers/accel/amdxdna/Makefile
>> b/drivers/accel/amdxdna/Makefile
>> index 79369e497540..d7720c8c8a98 100644
>> --- a/drivers/accel/amdxdna/Makefile
>> +++ b/drivers/accel/amdxdna/Makefile
>> @@ -12,6 +12,7 @@ amdxdna-y := \
>> aie2_solver.o \
>> aie4_message.o \
>> aie4_pci.o \
>> + amdxdna_cbuf.o \
>> amdxdna_ctx.o \
>> amdxdna_gem.o \
>> amdxdna_iommu.o \
>> @@ -28,4 +29,5 @@ amdxdna-y := \
>> npu6_regs.o
>> amdxdna-$(CONFIG_PCI_IOV) += aie4_sriov.o
>> +amdxdna-$(CONFIG_DEBUG_FS) += amdxdna_debugfs.o
>> obj-$(CONFIG_DRM_ACCEL_AMDXDNA) = amdxdna.o
>> diff --git a/drivers/accel/amdxdna/amdxdna_cbuf.c
>> b/drivers/accel/amdxdna/amdxdna_cbuf.c
>> new file mode 100644
>> index 000000000000..a504560aae98
>> --- /dev/null
>> +++ b/drivers/accel/amdxdna/amdxdna_cbuf.c
>> @@ -0,0 +1,280 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
>> + */
>> +
>> +#include <drm/drm_mm.h>
>> +#include <drm/drm_prime.h>
>> +
>> +#include "amdxdna_cbuf.h"
>> +#include "amdxdna_pci_drv.h"
>> +
>> +/*
>> + * Carveout memory is a chunk of memory which is physically
>> contiguous and
>> + * is reserved during early boot time. There is only one chunk of
>> such memory
>> + * per device. Once available, all BOs accessible from device should be
>> + * allocated from this memory. This is a platform debug/bringup
>> feature.
>> + */
>> +struct amdxdna_carveout {
>> + u64 addr;
>> + u64 size;
>> + struct drm_mm mm;
>> + struct mutex lock; /* protect mm */
>> +};
>> +
>> +bool amdxdna_use_carveout(struct amdxdna_dev *xdna)
>> +{
>> + return !!xdna->carveout;
>> +}
>> +
>> +void amdxdna_get_carveout_conf(struct amdxdna_dev *xdna, u64 *addr,
>> u64 *size)
>> +{
>> + if (amdxdna_use_carveout(xdna)) {
>> + *addr = xdna->carveout->addr;
>> + *size = xdna->carveout->size;
>> + } else {
>> + *addr = 0;
>> + *size = 0;
>> + }
>> +}
>> +
>> +int amdxdna_carveout_init(struct amdxdna_dev *xdna, u64
>> carveout_addr, u64 carveout_size)
>> +{
>> + struct amdxdna_carveout *carveout;
>> +
>> + /* Only allow carveout memory to be set up once. */
>> + if (amdxdna_use_carveout(xdna)) {
>> + XDNA_ERR(xdna, "Carveout memory has already been set up.");
>> + return -EBUSY;
>> + }
>> +
>> + carveout = kzalloc_obj(*carveout);
>> + if (!carveout)
>> + return -ENOMEM;
>> +
>> + carveout->addr = carveout_addr;
>> + carveout->size = carveout_size;
>> + mutex_init(&carveout->lock);
>> + drm_mm_init(&carveout->mm, carveout->addr, carveout->size);
>> +
>> + xdna->carveout = carveout;
>> + XDNA_INFO(xdna, "Use carveout mem: 0x%llx@0x%llx\n",
>> carveout->size, carveout->addr);
>> + return 0;
>> +}
>> +
>> +void amdxdna_carveout_fini(struct amdxdna_dev *xdna)
>> +{
>> + struct amdxdna_carveout *carveout = xdna->carveout;
>> +
>> + if (!amdxdna_use_carveout(xdna))
>> + return;
>> +
>> + XDNA_INFO(xdna, "Cleanup carveout mem: 0x%llx@0x%llx\n",
>> carveout->size, carveout->addr);
>> + drm_mm_takedown(&carveout->mm);
>> + mutex_destroy(&carveout->lock);
>> + kfree(carveout);
>> + xdna->carveout = NULL;
>> +}
>> +
>> +struct amdxdna_cbuf_priv {
>> + struct amdxdna_dev *xdna;
>> + struct drm_mm_node node;
>> +};
>> +
>> +static struct sg_table *amdxdna_cbuf_map(struct dma_buf_attachment
>> *attach,
>> + enum dma_data_direction direction)
>> +{
>> + struct amdxdna_cbuf_priv *cbuf = attach->dmabuf->priv;
>> + struct device *dev = attach->dev;
>> + struct scatterlist *sgl, *sg;
>> + int ret, n_entries, i;
>> + struct sg_table *sgt;
>> + dma_addr_t dma_addr;
>> + size_t dma_size;
>> + size_t max_seg;
>> +
>> + sgt = kzalloc_obj(*sgt);
>> + if (!sgt)
>> + return ERR_PTR(-ENOMEM);
>> +
>> + max_seg = min_t(size_t, UINT_MAX, dma_max_mapping_size(dev));
>> + n_entries = (cbuf->node.size + max_seg - 1) / max_seg;
>> + sgl = kzalloc_objs(*sg, n_entries);
>> + if (!sgl) {
>> + ret = -ENOMEM;
>> + goto free_sgt;
>> + }
>> + sg_init_table(sgl, n_entries);
>> + sgt->orig_nents = n_entries;
>> + sgt->nents = n_entries;
>> + sgt->sgl = sgl;
>> +
>> + dma_size = cbuf->node.size;
>> + dma_addr = dma_map_resource(dev, cbuf->node.start, dma_size,
>> + direction, DMA_ATTR_SKIP_CPU_SYNC);
>> + ret = dma_mapping_error(dev, dma_addr);
>> + if (ret) {
>> + pr_err("Failed to dma_map_resource carveout dma buf, ret
>> %d\n", ret);
>> + goto free_sgl;
>> + }
>> +
>> + for_each_sgtable_dma_sg(sgt, sg, i) {
>> + size_t len = min_t(size_t, max_seg, dma_size);
>> +
>> + sg_dma_address(sg) = dma_addr;
>> + sg_dma_len(sg) = len;
>> + dma_addr += len;
>> + dma_size -= len;
>> + }
>> +
>> + return sgt;
>> +
>> +free_sgl:
>> + kfree(sgl);
>> +free_sgt:
>> + kfree(sgt);
>> + return ERR_PTR(ret);
>> +}
>> +
>> +static void amdxdna_cbuf_unmap(struct dma_buf_attachment *attach,
>> + struct sg_table *sgt,
>> + enum dma_data_direction direction)
>> +{
>> + dma_unmap_resource(attach->dev, sg_dma_address(sgt->sgl),
>> + drm_prime_get_contiguous_size(sgt), direction,
>> + DMA_ATTR_SKIP_CPU_SYNC);
>> + sg_free_table(sgt);
>> + kfree(sgt);
>> +}
>> +
>> +static void amdxdna_cbuf_release(struct dma_buf *dbuf)
>> +{
>> + struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
>> + struct amdxdna_carveout *carveout;
>> +
>> + carveout = cbuf->xdna->carveout;
>> + mutex_lock(&carveout->lock);
>> + drm_mm_remove_node(&cbuf->node);
>> + mutex_unlock(&carveout->lock);
>> +
>> + kfree(cbuf);
>> +}
>> +
>> +static vm_fault_t amdxdna_cbuf_vm_fault(struct vm_fault *vmf)
>> +{
>> + struct vm_area_struct *vma = vmf->vma;
>> + struct amdxdna_cbuf_priv *cbuf;
>> + unsigned long pfn;
>> + pgoff_t pgoff;
>> +
>> + cbuf = vma->vm_private_data;
>> + pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
>> + pfn = (cbuf->node.start >> PAGE_SHIFT) + pgoff;
>> +
>> + return vmf_insert_pfn(vma, vmf->address, pfn);
>> +}
>> +
>> +static const struct vm_operations_struct amdxdna_cbuf_vm_ops = {
>> + .fault = amdxdna_cbuf_vm_fault,
>> +};
>> +
>> +static int amdxdna_cbuf_mmap(struct dma_buf *dbuf, struct
>> vm_area_struct *vma)
>> +{
>> + struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
>> +
>> + vma->vm_ops = &amdxdna_cbuf_vm_ops;
>> + vma->vm_private_data = cbuf;
>> + vm_flags_set(vma, VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP);
>> +
>> + return 0;
>> +}
>> +
>> +static int amdxdna_cbuf_vmap(struct dma_buf *dbuf, struct iosys_map
>> *map)
>> +{
>> + struct amdxdna_cbuf_priv *cbuf = dbuf->priv;
>> + void *kva;
>> +
>> + kva = memremap(cbuf->node.start, cbuf->node.size, MEMREMAP_WB);
>> + if (!kva) {
>> + pr_err("Failed to vmap carveout dma buf\n");
>> + return -ENOMEM;
>> + }
>> +
>> + iosys_map_set_vaddr(map, kva);
>> + return 0;
>> +}
>> +
>> +static void amdxdna_cbuf_vunmap(struct dma_buf *dbuf, struct
>> iosys_map *map)
>> +{
>> + memunmap(map->vaddr);
>> +}
>> +
>> +static const struct dma_buf_ops amdxdna_cbuf_dmabuf_ops = {
>> + .map_dma_buf = amdxdna_cbuf_map,
>> + .unmap_dma_buf = amdxdna_cbuf_unmap,
>> + .release = amdxdna_cbuf_release,
>> + .mmap = amdxdna_cbuf_mmap,
>> + .vmap = amdxdna_cbuf_vmap,
>> + .vunmap = amdxdna_cbuf_vunmap,
>> +};
>> +
>> +static int amdxdna_cbuf_clear(struct dma_buf *dbuf)
>> +{
>> + struct iosys_map vmap = IOSYS_MAP_INIT_VADDR(NULL);
>> +
>> + dma_buf_vmap(dbuf, &vmap);
>> + if (!vmap.vaddr)
>> + return -EFAULT;
>> +
>> + memset(vmap.vaddr, 0, dbuf->size);
>> + dma_buf_vunmap(dbuf, &vmap);
>> +
>> + return 0;
>> +}
>> +
>> +struct dma_buf *amdxdna_get_cbuf(struct drm_device *dev, size_t
>> size, u64 alignment)
>> +{
>> + struct amdxdna_dev *xdna = to_xdna_dev(dev);
>> + DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
>> + struct amdxdna_carveout *carveout;
>> + struct amdxdna_cbuf_priv *cbuf;
>> + struct dma_buf *dbuf;
>> + int ret;
>> +
>> + cbuf = kzalloc_obj(*cbuf);
>> + if (!cbuf)
>> + return ERR_PTR(-ENOMEM);
>> + cbuf->xdna = xdna;
>> +
>> + carveout = xdna->carveout;
>> + mutex_lock(&carveout->lock);
>> + ret = drm_mm_insert_node_generic(&carveout->mm, &cbuf->node, size,
>> + alignment, 0, DRM_MM_INSERT_BEST);
>> + mutex_unlock(&carveout->lock);
>> + if (ret)
>> + goto free_cbuf;
>> +
>> + exp_info.size = size;
>> + exp_info.ops = &amdxdna_cbuf_dmabuf_ops;
>> + exp_info.priv = cbuf;
>> + exp_info.flags = O_RDWR;
>> + dbuf = dma_buf_export(&exp_info);
>> + if (IS_ERR(dbuf)) {
>> + ret = PTR_ERR(dbuf);
>> + goto remove_node;
>> + }
>> +
>> + ret = amdxdna_cbuf_clear(dbuf);
>> + if (ret) {
>> + dma_buf_put(dbuf);
>> + goto out;
>> + }
>> + return dbuf;
>> +
>> +remove_node:
>> + drm_mm_remove_node(&cbuf->node);
>> +free_cbuf:
>> + kfree(cbuf);
>> +out:
>> + return ERR_PTR(ret);
>> +}
>> diff --git a/drivers/accel/amdxdna/amdxdna_cbuf.h
>> b/drivers/accel/amdxdna/amdxdna_cbuf.h
>> new file mode 100644
>> index 000000000000..8e89336ffd50
>> --- /dev/null
>> +++ b/drivers/accel/amdxdna/amdxdna_cbuf.h
>> @@ -0,0 +1,18 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
>> + */
>> +#ifndef _AMDXDNA_CBUF_H_
>> +#define _AMDXDNA_CBUF_H_
>> +
>> +#include "amdxdna_pci_drv.h"
>> +#include <drm/drm_device.h>
>> +#include <linux/dma-buf.h>
>> +
>> +bool amdxdna_use_carveout(struct amdxdna_dev *xdna);
>> +int amdxdna_carveout_init(struct amdxdna_dev *xdna, u64
>> carveout_addr, u64 carveout_size);
>> +void amdxdna_carveout_fini(struct amdxdna_dev *xdna);
>> +void amdxdna_get_carveout_conf(struct amdxdna_dev *xdna, u64 *addr,
>> u64 *size);
>> +struct dma_buf *amdxdna_get_cbuf(struct drm_device *dev, size_t
>> size, u64 alignment);
>> +
>> +#endif
>> diff --git a/drivers/accel/amdxdna/amdxdna_debugfs.c
>> b/drivers/accel/amdxdna/amdxdna_debugfs.c
>> new file mode 100644
>> index 000000000000..a6ec17c63629
>> --- /dev/null
>> +++ b/drivers/accel/amdxdna/amdxdna_debugfs.c
>> @@ -0,0 +1,129 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
>> + */
>> +
>> +#include "amdxdna_cbuf.h"
>> +#include "amdxdna_debugfs.h"
>> +
>> +#include <drm/drm_file.h>
>> +#include <linux/debugfs.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/seq_file.h>
>> +#include <linux/string.h>
>> +#include <linux/uaccess.h>
>> +
>> +#define _DBGFS_FOPS(_open, _release, _write) \
>> +{ \
>> + .owner = THIS_MODULE, \
>> + .open = _open, \
>> + .read = seq_read, \
>> + .llseek = seq_lseek, \
>> + .release = _release, \
>> + .write = _write, \
>> +}
>> +
>> +#define AMDXDNA_DBGFS_FOPS(_name, _show, _write) \
>> + static int amdxdna_dbgfs_##_name##_open(struct inode *inode,
>> struct file *file) \
>> + { \
>> + return single_open(file, _show, inode->i_private); \
>> + } \
>> + static int amdxdna_dbgfs_##_name##_release(struct inode *inode,
>> struct file *file) \
>> + { \
>> + return single_release(inode, file); \
>> + } \
>> + static const struct file_operations amdxdna_fops_##_name = \
>> + _DBGFS_FOPS(amdxdna_dbgfs_##_name##_open,
>> amdxdna_dbgfs_##_name##_release, _write)
>> +
>> +#define AMDXDNA_DBGFS_FILE(_name, _mode) { #_name,
>> &amdxdna_fops_##_name, _mode }
>> +
>> +#define file_to_xdna(file) (((struct seq_file
>> *)(file)->private_data)->private)
>> +
>> +static ssize_t amdxdna_carveout_write(struct file *file, const char
>> __user *buf,
>> + size_t count, loff_t *ppos)
>> +{
>> + struct amdxdna_dev *xdna = file_to_xdna(file);
>> + char kbuf[128];
>> + u64 size, addr;
>> + char *sep;
>> + int ret;
>> +
>> + if (count == 0 || count >= sizeof(kbuf))
>> + return -EINVAL;
>> +
>> + if (copy_from_user(kbuf, buf, count))
>> + return -EFAULT;
>> + kbuf[count] = '\0';
>> + strim(kbuf);
>> + XDNA_DBG(xdna, "Trying to set carveout to %s", kbuf);
>> +
>> + sep = strchr(kbuf, '@');
>> + if (!sep)
>> + return -EINVAL;
>> + *sep = '\0';
>> + sep++;
>> +
>> + ret = kstrtou64(kbuf, 0, &size);
>> + if (ret)
>> + return ret;
>> +
>> + ret = kstrtou64(sep, 0, &addr);
>> + if (ret)
>> + return ret;
>> +
>> + /* Sanity check the addr and size. */
>> + if (!size)
>> + return -EINVAL;
>> + if (!IS_ALIGNED(addr, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE))
>> + return -EINVAL;
>> +
>> + guard(mutex)(&xdna->dev_lock);
>> +
>> + ret = amdxdna_carveout_init(xdna, addr, size);
>> + if (ret)
>> + return ret;
>> +
>> + return count;
>> +}
>> +
>> +static int amdxdna_carveout_show(struct seq_file *m, void *unused)
>> +{
>> + struct amdxdna_dev *xdna = m->private;
>> + u64 addr, size;
>> +
>> + guard(mutex)(&xdna->dev_lock);
>> + amdxdna_get_carveout_conf(xdna, &addr, &size);
>> + seq_printf(m, "0x%llx@0x%llx\n", size, addr);
>> + return 0;
>> +}
>> +
>> +/*
>> + * Input/output format: <carveout_size>@<carveout_address>
>> + */
>> +AMDXDNA_DBGFS_FOPS(carveout, amdxdna_carveout_show,
>> amdxdna_carveout_write);
>> +
>> +static const struct {
>> + const char *name;
>> + const struct file_operations *fops;
>> + umode_t mode;
>> +} amdxdna_dbgfs_files[] = {
>> + AMDXDNA_DBGFS_FILE(carveout, 0600),
>> +};
>> +
>> +void amdxdna_debugfs_init(struct amdxdna_dev *xdna)
>> +{
>> + struct drm_minor *minor = xdna->ddev.accel;
>> + int i;
>> +
>> + /*
>> + * It should be okay that debugfs fails to init.
>> + * We rely on DRM framework to finish debugfs.
>> + */
>> + for (i = 0; i < ARRAY_SIZE(amdxdna_dbgfs_files); i++) {
>> + debugfs_create_file(amdxdna_dbgfs_files[i].name,
>> + amdxdna_dbgfs_files[i].mode,
>> + minor->debugfs_root,
>> + xdna,
>> + amdxdna_dbgfs_files[i].fops);
>> + }
>> +}
>> diff --git a/drivers/accel/amdxdna/amdxdna_debugfs.h
>> b/drivers/accel/amdxdna/amdxdna_debugfs.h
>> new file mode 100644
>> index 000000000000..2abb45de3f7e
>> --- /dev/null
>> +++ b/drivers/accel/amdxdna/amdxdna_debugfs.h
>> @@ -0,0 +1,18 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2026, Advanced Micro Devices, Inc.
>> + */
>> +#ifndef _AMDXDNA_DEBUGFS_H_
>> +#define _AMDXDNA_DEBUGFS_H_
>> +
>> +#include "amdxdna_pci_drv.h"
>> +
>> +#if defined(CONFIG_DEBUG_FS)
>> +void amdxdna_debugfs_init(struct amdxdna_dev *xdna);
>> +#else
>> +static inline void amdxdna_debugfs_init(struct amdxdna_dev *xdna)
>> +{
>> +}
>> +#endif /* CONFIG_DEBUG_FS */
>> +
>> +#endif
>> diff --git a/drivers/accel/amdxdna/amdxdna_gem.c
>> b/drivers/accel/amdxdna/amdxdna_gem.c
>> index 238ee244d4a6..ebfc472aa9e7 100644
>> --- a/drivers/accel/amdxdna/amdxdna_gem.c
>> +++ b/drivers/accel/amdxdna/amdxdna_gem.c
>> @@ -16,6 +16,7 @@
>> #include <linux/pagemap.h>
>> #include <linux/vmalloc.h>
>> +#include "amdxdna_cbuf.h"
>> #include "amdxdna_ctx.h"
>> #include "amdxdna_gem.h"
>> #include "amdxdna_pci_drv.h"
>> @@ -516,10 +517,6 @@ static void amdxdna_imported_obj_free(struct
>> amdxdna_gem_obj *abo)
>> static inline bool
>> amdxdna_gem_skip_bo_usage(struct amdxdna_gem_obj *abo)
>> {
>> - /* Do not count imported BOs since the buffer is not allocated
>> by us. */
>> - if (is_import_bo(abo))
>> - return true;
>> -
>> /* Already counted as part of HEAP BO */
>> if (abo->type == AMDXDNA_BO_DEV)
>> return true;
>> @@ -571,9 +568,7 @@ static void amdxdna_gem_obj_free(struct
>> drm_gem_object *gobj)
>> if (abo->type == AMDXDNA_BO_DEV_HEAP)
>> drm_mm_takedown(&abo->mm);
>> - if (amdxdna_iova_on(xdna))
>> - amdxdna_iommu_unmap_bo(xdna, abo);
>> -
>> + amdxdna_dma_unmap_bo(xdna, abo);
>> amdxdna_gem_vunmap(abo);
>> mutex_destroy(&abo->lock);
>> @@ -591,18 +586,20 @@ static int amdxdna_gem_obj_open(struct
>> drm_gem_object *gobj, struct drm_file *fi
>> guard(mutex)(&abo->lock);
>> abo->open_ref++;
>> + if (abo->open_ref > 1)
>> + return 0;
>> - if (abo->open_ref == 1) {
>> - /* Attached to the client when first opened by it. */
>> - abo->client = filp->driver_priv;
>> - amdxdna_gem_add_bo_usage(abo);
>> - }
>> - if (amdxdna_iova_on(xdna)) {
>> - ret = amdxdna_iommu_map_bo(xdna, abo);
>> + /* Attached to the client when first opened by it. */
>> + abo->client = filp->driver_priv;
>> +
>> + /* No need to set up dma addr mapping in PASID mode. */
>> + if (!amdxdna_pasid_on(abo->client)) {
>> + ret = amdxdna_dma_map_bo(xdna, abo);
>> if (ret)
>> return ret;
>> }
>> + amdxdna_gem_add_bo_usage(abo);
>> return 0;
>> }
>> @@ -620,6 +617,39 @@ static void amdxdna_gem_obj_close(struct
>> drm_gem_object *gobj, struct drm_file *
>> }
>> }
>> +static int amdxdna_gem_obj_vmap(struct drm_gem_object *obj, struct
>> iosys_map *map)
>> +{
>> + struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
>> + int ret;
>> +
>> + iosys_map_clear(map);
>> +
>> + dma_resv_assert_held(obj->resv);
>> +
>> + if (is_import_bo(abo))
>> + ret = dma_buf_vmap(abo->dma_buf, map);
>> + else
>> + ret = drm_gem_shmem_object_vmap(obj, map);
>> + if (ret)
>> + return ret;
>> + if (!map->vaddr)
>> + return -ENOMEM;
>> +
>> + return 0;
>> +}
>> +
>> +static void amdxdna_gem_obj_vunmap(struct drm_gem_object *obj,
>> struct iosys_map *map)
>> +{
>> + struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
>> +
>> + dma_resv_assert_held(obj->resv);
>> +
>> + if (is_import_bo(abo))
>> + dma_buf_vunmap(abo->dma_buf, map);
>> + else
>> + drm_gem_shmem_object_vunmap(obj, map);
>> +}
>> +
>> static int amdxdna_gem_dev_obj_vmap(struct drm_gem_object *obj,
>> struct iosys_map *map)
>> {
>> struct amdxdna_gem_obj *abo = to_xdna_obj(obj);
>> @@ -645,8 +675,8 @@ static const struct drm_gem_object_funcs
>> amdxdna_gem_shmem_funcs = {
>> .pin = drm_gem_shmem_object_pin,
>> .unpin = drm_gem_shmem_object_unpin,
>> .get_sg_table = drm_gem_shmem_object_get_sg_table,
>> - .vmap = drm_gem_shmem_object_vmap,
>> - .vunmap = drm_gem_shmem_object_vunmap,
>> + .vmap = amdxdna_gem_obj_vmap,
>> + .vunmap = amdxdna_gem_obj_vunmap,
>> .mmap = amdxdna_gem_obj_mmap,
>> .vm_ops = &drm_gem_shmem_vm_ops,
>> .export = amdxdna_gem_prime_export,
>> @@ -714,6 +744,36 @@ amdxdna_gem_create_ubuf_object(struct drm_device
>> *dev, struct amdxdna_drm_create
>> return to_xdna_obj(gobj);
>> }
>> +static struct amdxdna_gem_obj *
>> +amdxdna_gem_create_cbuf_object(struct drm_device *dev, struct
>> amdxdna_drm_create_bo *args)
>> +{
>> + struct amdxdna_dev *xdna = to_xdna_dev(dev);
>> + size_t size = PAGE_ALIGN(args->size);
>> + struct drm_gem_object *gobj;
>> + struct amdxdna_gem_obj *ret;
>> + struct dma_buf *dma_buf;
>> + u64 align;
>> +
>> + if (!size) {
>> + XDNA_ERR(xdna, "Invalid BO size 0x%llx", args->size);
>> + return ERR_PTR(-EINVAL);
>> + }
>> +
>> + align = (args->type == AMDXDNA_BO_DEV_HEAP) ?
>> xdna->dev_info->dev_mem_size : 0;
>> + dma_buf = amdxdna_get_cbuf(dev, size, align);
>> + if (IS_ERR(dma_buf))
>> + return ERR_CAST(dma_buf);
>> +
>> + gobj = amdxdna_gem_prime_import(dev, dma_buf);
>> + if (IS_ERR(gobj))
>> + ret = ERR_CAST(gobj);
>> + else
>> + ret = to_xdna_obj(gobj);
>> +
>> + dma_buf_put(dma_buf);
>> + return ret;
>> +}
>> +
>> struct drm_gem_object *
>> amdxdna_gem_prime_import(struct drm_device *dev, struct dma_buf
>> *dma_buf)
>> {
>> @@ -769,6 +829,8 @@ amdxdna_drm_create_share_bo(struct drm_device *dev,
>> if (args->vaddr)
>> abo = amdxdna_gem_create_ubuf_object(dev, args);
>> + else if (amdxdna_use_carveout(to_xdna_dev(dev)))
>> + abo = amdxdna_gem_create_cbuf_object(dev, args);
>> else
>> abo = amdxdna_gem_create_shmem_object(dev, args);
>> if (IS_ERR(abo))
>> @@ -884,7 +946,6 @@ int amdxdna_drm_create_bo_ioctl(struct drm_device
>> *dev, void *data, struct drm_f
>> args->type, args->vaddr, args->size, args->flags);
>> switch (args->type) {
>> case AMDXDNA_BO_CMD:
>> - fallthrough;
>> case AMDXDNA_BO_SHARE:
>> abo = amdxdna_drm_create_share_bo(dev, args, filp);
>> break;
>> diff --git a/drivers/accel/amdxdna/amdxdna_iommu.c
>> b/drivers/accel/amdxdna/amdxdna_iommu.c
>> index 5a9f06183487..eff00131d0f8 100644
>> --- a/drivers/accel/amdxdna/amdxdna_iommu.c
>> +++ b/drivers/accel/amdxdna/amdxdna_iommu.c
>> @@ -35,14 +35,15 @@ static struct iova
>> *amdxdna_iommu_alloc_iova(struct amdxdna_dev *xdna,
>> return iova;
>> }
>> -int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo)
>> +int amdxdna_dma_map_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo)
>> {
>> + unsigned long contig_sz;
>> struct sg_table *sgt;
>> dma_addr_t dma_addr;
>> struct iova *iova;
>> ssize_t size;
>> - if (abo->type != AMDXDNA_BO_DEV_HEAP && abo->type !=
>> AMDXDNA_BO_SHMEM)
>> + if (abo->type != AMDXDNA_BO_DEV_HEAP && abo->type !=
>> AMDXDNA_BO_SHARE)
>> return 0;
>> sgt = drm_gem_shmem_get_pages_sgt(&abo->base);
>> @@ -51,47 +52,63 @@ int amdxdna_iommu_map_bo(struct amdxdna_dev
>> *xdna, struct amdxdna_gem_obj *abo)
>> return PTR_ERR(sgt);
>> }
>> - if (!sgt->orig_nents || !sg_page(sgt->sgl)) {
>> - XDNA_ERR(xdna, "sgl is zero length or not page backed");
>> + if (!sgt->orig_nents) {
>> + XDNA_ERR(xdna, "sgl is zero length");
>> return -EOPNOTSUPP;
>> }
>> - iova = amdxdna_iommu_alloc_iova(xdna, abo->mem.size, &dma_addr,
>> - (abo->type == AMDXDNA_BO_DEV_HEAP));
>> - if (IS_ERR(iova)) {
>> - XDNA_ERR(xdna, "Alloc iova failed, ret %ld", PTR_ERR(iova));
>> - return PTR_ERR(iova);
>> + if (amdxdna_iova_on(xdna)) {
>> + if (!sg_page(sgt->sgl)) {
>> + XDNA_ERR(xdna, "sgl is not page backed");
>> + return -EOPNOTSUPP;
>> + }
>> +
>> + iova = amdxdna_iommu_alloc_iova(xdna, abo->mem.size, &dma_addr,
>> + (abo->type == AMDXDNA_BO_DEV_HEAP));
>> + if (IS_ERR(iova)) {
>> + XDNA_ERR(xdna, "Alloc iova failed, ret %ld",
>> PTR_ERR(iova));
>> + return PTR_ERR(iova);
>> + }
>> +
>> + size = iommu_map_sgtable(xdna->domain, dma_addr, sgt,
>> + IOMMU_READ | IOMMU_WRITE);
>> + if (size < 0) {
>> + XDNA_ERR(xdna, "iommu_map_sgtable failed: %zd", size);
>> + __free_iova(&xdna->iovad, iova);
>> + return size;
>> + }
>> + if (size < abo->mem.size) {
>> + iommu_unmap(xdna->domain, dma_addr, size);
>> + __free_iova(&xdna->iovad, iova);
>> + return -ENXIO;
>> + }
>> + abo->mem.dma_addr = dma_addr;
>> + } else {
>> + /* Device doesn't support scatter/gather list, fail
>> non-contiguous mapping. */
>> + contig_sz = drm_prime_get_contiguous_size(sgt);
>> + if (contig_sz < abo->mem.size) {
>> + XDNA_ERR(xdna,
>> + "noncontiguous dma addr, contig size:%ld, expected
>> size:%ld",
>> + contig_sz, abo->mem.size);
>> + return -EINVAL;
>> + }
>> + abo->mem.dma_addr = sg_dma_address(sgt->sgl);
>> }
>> -
>> - size = iommu_map_sgtable(xdna->domain, dma_addr, sgt,
>> - IOMMU_READ | IOMMU_WRITE);
>> - if (size < 0) {
>> - XDNA_ERR(xdna, "iommu_map_sgtable failed: %zd", size);
>> - __free_iova(&xdna->iovad, iova);
>> - return size;
>> - }
>> -
>> - if (size < abo->mem.size) {
>> - iommu_unmap(xdna->domain, dma_addr, size);
>> - __free_iova(&xdna->iovad, iova);
>> - return -ENXIO;
>> - }
>> -
>> - abo->mem.dma_addr = dma_addr;
>> -
>> return 0;
>> }
>> -void amdxdna_iommu_unmap_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo)
>> +void amdxdna_dma_unmap_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo)
>> {
>> size_t size;
>> if (abo->mem.dma_addr == AMDXDNA_INVALID_ADDR)
>> return;
>> - size = iova_align(&xdna->iovad, abo->mem.size);
>> - iommu_unmap(xdna->domain, abo->mem.dma_addr, size);
>> - free_iova(&xdna->iovad, iova_pfn(&xdna->iovad, abo->mem.dma_addr));
>> + if (amdxdna_iova_on(xdna)) {
>> + size = iova_align(&xdna->iovad, abo->mem.size);
>> + iommu_unmap(xdna->domain, abo->mem.dma_addr, size);
>> + free_iova(&xdna->iovad, iova_pfn(&xdna->iovad,
>> abo->mem.dma_addr));
>> + }
>> abo->mem.dma_addr = AMDXDNA_INVALID_ADDR;
>> }
>> diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.c
>> b/drivers/accel/amdxdna/amdxdna_pci_drv.c
>> index 21eddfc538d0..1b08a08343cf 100644
>> --- a/drivers/accel/amdxdna/amdxdna_pci_drv.c
>> +++ b/drivers/accel/amdxdna/amdxdna_pci_drv.c
>> @@ -14,7 +14,9 @@
>> #include <linux/iommu.h>
>> #include <linux/pci.h>
>> +#include "amdxdna_cbuf.h"
>> #include "amdxdna_ctx.h"
>> +#include "amdxdna_debugfs.h"
>> #include "amdxdna_gem.h"
>> #include "amdxdna_pci_drv.h"
>> #include "amdxdna_pm.h"
>> @@ -67,11 +69,40 @@ static const struct amdxdna_device_id
>> amdxdna_ids[] = {
>> {0}
>> };
>> +static int amdxdna_sva_init(struct amdxdna_client *client)
>> +{
>> + struct amdxdna_dev *xdna = client->xdna;
>> +
>> + client->sva = iommu_sva_bind_device(xdna->ddev.dev, client->mm);
>> + if (IS_ERR(client->sva)) {
>> + XDNA_ERR(xdna, "SVA bind device failed, ret %ld",
>> PTR_ERR(client->sva));
>> + return PTR_ERR(client->sva);
>> + }
>> +
>> + client->pasid = iommu_sva_get_pasid(client->sva);
>> + if (client->pasid == IOMMU_PASID_INVALID) {
>> + iommu_sva_unbind_device(client->sva);
>> + XDNA_ERR(xdna, "SVA get pasid failed");
>> + return -ENODEV;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static void amdxdna_sva_fini(struct amdxdna_client *client)
>> +{
>> + if (IS_ERR_OR_NULL(client->sva))
>> + return;
>> +
>> + iommu_sva_unbind_device(client->sva);
>> + client->sva = NULL;
>> + client->pasid = IOMMU_PASID_INVALID;
>> +}
>> +
>> static int amdxdna_drm_open(struct drm_device *ddev, struct
>> drm_file *filp)
>> {
>> struct amdxdna_dev *xdna = to_xdna_dev(ddev);
>> struct amdxdna_client *client;
>> - int ret;
>> client = kzalloc_obj(*client);
>> if (!client)
>> @@ -80,22 +111,13 @@ static int amdxdna_drm_open(struct drm_device
>> *ddev, struct drm_file *filp)
>> client->pid = pid_nr(rcu_access_pointer(filp->pid));
>> client->xdna = xdna;
>> client->pasid = IOMMU_PASID_INVALID;
>> + client->mm = current->mm;
>> if (!amdxdna_iova_on(xdna)) {
>> - client->sva = iommu_sva_bind_device(xdna->ddev.dev,
>> current->mm);
>> - if (IS_ERR(client->sva)) {
>> - ret = PTR_ERR(client->sva);
>> - XDNA_ERR(xdna, "SVA bind device failed, ret %d", ret);
>> - goto failed;
>> - }
>> - client->pasid = iommu_sva_get_pasid(client->sva);
>> - if (client->pasid == IOMMU_PASID_INVALID) {
>> - XDNA_ERR(xdna, "SVA get pasid failed");
>> - ret = -ENODEV;
>> - goto unbind_sva;
>> - }
>> + /* No need to fail open since user may use pa + carveout
>> later. */
>> + if (amdxdna_sva_init(client))
>> + XDNA_WARN(xdna, "PASID not available for pid %d",
>> client->pid);
>> }
>> - client->mm = current->mm;
>> mmgrab(client->mm);
>> init_srcu_struct(&client->hwctx_srcu);
>> xa_init_flags(&client->hwctx_xa, XA_FLAGS_ALLOC);
>> @@ -110,14 +132,6 @@ static int amdxdna_drm_open(struct drm_device
>> *ddev, struct drm_file *filp)
>> XDNA_DBG(xdna, "pid %d opened", client->pid);
>> return 0;
>> -
>> -unbind_sva:
>> - if (!IS_ERR_OR_NULL(client->sva))
>> - iommu_sva_unbind_device(client->sva);
>> -failed:
>> - kfree(client);
>> -
>> - return ret;
>> }
>> static void amdxdna_client_cleanup(struct amdxdna_client *client)
>> @@ -131,11 +145,8 @@ static void amdxdna_client_cleanup(struct
>> amdxdna_client *client)
>> drm_gem_object_put(to_gobj(client->dev_heap));
>> mutex_destroy(&client->mm_lock);
>> -
>> - if (!IS_ERR_OR_NULL(client->sva))
>> - iommu_sva_unbind_device(client->sva);
>> mmdrop(client->mm);
>> -
>> + amdxdna_sva_fini(client);
>> kfree(client);
>> }
>> @@ -242,15 +253,17 @@ static void amdxdna_show_fdinfo(struct
>> drm_printer *p, struct drm_file *filp)
>> /*
>> * Note for driver specific BO memory usage stat.
>> - * Total memory alloc = amdxdna-internal-alloc +
>> amdxdna-external-alloc
>> + * Total memory in use = amdxdna-internal-alloc +
>> amdxdna-external-alloc, which
>> + * includes both imported and created BOs. To avoid double
>> counts, it includes
>> + * HEAP BO, but not DEV BO. DEV BO is counted by
>> amdxdna-heap-alloc.
>> */
>> drm_fdinfo_print_size(p, drv_name, "heap", "alloc", heap_usage);
>> drm_fdinfo_print_size(p, drv_name, "internal", "alloc",
>> internal_usage);
>> drm_fdinfo_print_size(p, drv_name, "external", "alloc",
>> external_usage);
>> /*
>> * Note for DRM standard BO memory stat.
>> - * drm-total-memory counts both DEV BO and HEAP BO
>> - * drm-shared-memory counts BO imported
>> + * drm-total-memory counts both DEV BO and HEAP BO. The DEV BO
>> size is double counted.
>> + * drm-shared-memory counts BO shared with other processes/devices.
>> */
>> drm_show_memory_stats(p, filp);
>> }
>> @@ -299,25 +312,38 @@ amdxdna_get_dev_info(struct pci_dev *pdev)
>> return NULL;
>> }
>> +static void amdxdna_xdna_drm_release(struct drm_device *drm, void
>> *res)
>> +{
>> + struct amdxdna_dev *xdna = res;
>> +
>> + amdxdna_carveout_fini(xdna);
>> +}
>> +
>> static int amdxdna_probe(struct pci_dev *pdev, const struct
>> pci_device_id *id)
>> {
>> struct device *dev = &pdev->dev;
>> struct amdxdna_dev *xdna;
>> + struct drm_device *ddev;
>> int ret;
>> xdna = devm_drm_dev_alloc(dev, &amdxdna_drm_drv,
>> typeof(*xdna), ddev);
>> if (IS_ERR(xdna))
>> return PTR_ERR(xdna);
>> + ddev = &xdna->ddev;
>> xdna->dev_info = amdxdna_get_dev_info(pdev);
>> if (!xdna->dev_info)
>> return -ENODEV;
>> - drmm_mutex_init(&xdna->ddev, &xdna->dev_lock);
>> + drmm_mutex_init(ddev, &xdna->dev_lock);
>> init_rwsem(&xdna->notifier_lock);
>> INIT_LIST_HEAD(&xdna->client_list);
>> pci_set_drvdata(pdev, xdna);
>> + ret = drmm_add_action(ddev, amdxdna_xdna_drm_release, xdna);
>> + if (ret)
>> + return ret;
>> +
>> if (IS_ENABLED(CONFIG_LOCKDEP)) {
>> fs_reclaim_acquire(GFP_KERNEL);
>> might_lock(&xdna->notifier_lock);
>> @@ -348,12 +374,13 @@ static int amdxdna_probe(struct pci_dev *pdev,
>> const struct pci_device_id *id)
>> goto failed_dev_fini;
>> }
>> - ret = drm_dev_register(&xdna->ddev, 0);
>> + ret = drm_dev_register(ddev, 0);
>> if (ret) {
>> XDNA_ERR(xdna, "DRM register failed, ret %d", ret);
>> goto failed_sysfs_fini;
>> }
>> + amdxdna_debugfs_init(xdna);
>> return 0;
>> failed_sysfs_fini:
>> diff --git a/drivers/accel/amdxdna/amdxdna_pci_drv.h
>> b/drivers/accel/amdxdna/amdxdna_pci_drv.h
>> index bdd0dc83f92e..b1548cf16f59 100644
>> --- a/drivers/accel/amdxdna/amdxdna_pci_drv.h
>> +++ b/drivers/accel/amdxdna/amdxdna_pci_drv.h
>> @@ -104,6 +104,8 @@ struct amdxdna_fw_ver {
>> u32 build;
>> };
>> +struct amdxdna_carveout;
>> +
>> struct amdxdna_dev {
>> struct drm_device ddev;
>> struct amdxdna_dev_hdl *dev_handle;
>> @@ -121,6 +123,8 @@ struct amdxdna_dev {
>> struct iova_domain iovad;
>> /* Accurate board name queried from firmware, or default_vbnv
>> as fallback */
>> const char *vbnv;
>> +
>> + struct amdxdna_carveout *carveout;
>> };
>> /*
>> @@ -172,11 +176,11 @@ void amdxdna_sysfs_fini(struct amdxdna_dev *xdna);
>> int amdxdna_iommu_init(struct amdxdna_dev *xdna);
>> void amdxdna_iommu_fini(struct amdxdna_dev *xdna);
>> -int amdxdna_iommu_map_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo);
>> -void amdxdna_iommu_unmap_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo);
>> void *amdxdna_iommu_alloc(struct amdxdna_dev *xdna, size_t size,
>> dma_addr_t *dma_addr);
>> void amdxdna_iommu_free(struct amdxdna_dev *xdna, size_t size,
>> void *cpu_addr, dma_addr_t dma_addr);
>> +int amdxdna_dma_map_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo);
>> +void amdxdna_dma_unmap_bo(struct amdxdna_dev *xdna, struct
>> amdxdna_gem_obj *abo);
>> static inline bool amdxdna_iova_on(struct amdxdna_dev *xdna)
>> {
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2026-05-05 15:33 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2026-04-27 17:09 [PATCH V2] accel/amdxdna: Add carveout memory support for non-IOMMU systems Lizhi Hou
2026-05-04 19:08 ` Mario Limonciello
2026-05-05 15:32 ` Lizhi Hou
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