Commit 38290b2c authored by Tom St Denis's avatar Tom St Denis Committed by Alex Deucher

drm/amd/amdgpu: add support for iova_to_phys to replace TTM trace (v5)

Signed-off-by: default avatarTom St Denis <tom.stdenis@amd.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>

(v2): Add domain to iova debugfs
(v3): Add true read/write methods to access system memory of pages
      mapped to the device
(v4): Move get_domain call out of loop and return on error
(v5): Just use kmap/kunmap
parent a40cfa0b
......@@ -43,6 +43,7 @@
#include <linux/swap.h>
#include <linux/pagemap.h>
#include <linux/debugfs.h>
#include <linux/iommu.h>
#include "amdgpu.h"
#include "amdgpu_trace.h"
#include "bif/bif_4_1_d.h"
......@@ -1809,7 +1810,104 @@ static const struct file_operations amdgpu_ttm_gtt_fops = {
#endif
static ssize_t amdgpu_iova_to_phys_read(struct file *f, char __user *buf,
size_t size, loff_t *pos)
{
struct amdgpu_device *adev = file_inode(f)->i_private;
ssize_t result, n;
int r;
uint64_t phys;
void *ptr;
struct iommu_domain *dom;
dom = iommu_get_domain_for_dev(adev->dev);
if (!dom)
return -EFAULT;
result = 0;
while (size) {
// get physical address and map
phys = iommu_iova_to_phys(dom, *pos);
// copy upto one page
if (size > PAGE_SIZE)
n = PAGE_SIZE;
else
n = size;
// to end of the page
if (((*pos & (PAGE_SIZE - 1)) + n) >= PAGE_SIZE)
n = PAGE_SIZE - (*pos & (PAGE_SIZE - 1));
ptr = kmap(pfn_to_page(PFN_DOWN(phys)));
if (!ptr)
return -EFAULT;
r = copy_to_user(buf, ptr, n);
kunmap(pfn_to_page(PFN_DOWN(phys)));
if (r)
return -EFAULT;
*pos += n;
size -= n;
result += n;
}
return result;
}
static ssize_t amdgpu_iova_to_phys_write(struct file *f, const char __user *buf,
size_t size, loff_t *pos)
{
struct amdgpu_device *adev = file_inode(f)->i_private;
ssize_t result, n;
int r;
uint64_t phys;
void *ptr;
struct iommu_domain *dom;
dom = iommu_get_domain_for_dev(adev->dev);
if (!dom)
return -EFAULT;
result = 0;
while (size) {
// get physical address and map
phys = iommu_iova_to_phys(dom, *pos);
// copy upto one page
if (size > PAGE_SIZE)
n = PAGE_SIZE;
else
n = size;
// to end of the page
if (((*pos & (PAGE_SIZE - 1)) + n) >= PAGE_SIZE)
n = PAGE_SIZE - (*pos & (PAGE_SIZE - 1));
ptr = kmap(pfn_to_page(PFN_DOWN(phys)));
if (!ptr)
return -EFAULT;
r = copy_from_user(ptr, buf, n);
kunmap(pfn_to_page(PFN_DOWN(phys)));
if (r)
return -EFAULT;
*pos += n;
size -= n;
result += n;
}
return result;
}
static const struct file_operations amdgpu_ttm_iova_fops = {
.owner = THIS_MODULE,
.read = amdgpu_iova_to_phys_read,
.write = amdgpu_iova_to_phys_write,
.llseek = default_llseek
};
static const struct {
char *name;
......@@ -1820,6 +1918,7 @@ static const struct {
#ifdef CONFIG_DRM_AMDGPU_GART_DEBUGFS
{ "amdgpu_gtt", &amdgpu_ttm_gtt_fops, TTM_PL_TT },
#endif
{ "amdgpu_iova", &amdgpu_ttm_iova_fops, TTM_PL_SYSTEM },
};
#endif
......
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