[PATCH for-next 06/10] IB/mlx4: Add mmap call to map the hardware clock

Or Gerlitz
2015-05-17T13:36:22Z

From: Matan Barak <matanb-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>

In order to read the HCA's cycle counter efficiently in
user space, we need to map the HCA's register.
This is done through mmap call.

Signed-off-by: Matan Barak <matanb-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Signed-off-by: Or Gerlitz <ogerlitz-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
---
drivers/infiniband/hw/mlx4/main.c | 18 +++++++++++++++++-
drivers/net/ethernet/mellanox/mlx4/main.c | 19 +++++++++++++++++++
include/linux/mlx4/device.h | 9 +++++++++
3 files changed, 45 insertions(+), 1 deletions(-)

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index fe697ec..1b60687 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -725,8 +725,24 @@ static int mlx4_ib_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
dev->dev->caps.num_uars,
PAGE_SIZE, vma->vm_page_prot))
return -EAGAIN;
- } else
+ } else if (vma->vm_pgoff == 3) {
+ struct mlx4_clock_params params;
+ int ret = mlx4_get_internal_clock_params(dev->dev, &params);
+
+ if (ret)
+ return ret;
+
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ if (io_remap_pfn_range(vma, vma->vm_start,
+ (pci_resource_start(dev->dev->persist->pdev,
+ params.bar) +
+ params.offset)
+ >> PAGE_SHIFT,
+ PAGE_SIZE, vma->vm_page_prot))
+ return -EAGAIN;
+ } else {
return -EINVAL;
+ }

return 0;
}
diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index ced5eca..70de39c 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -1674,6 +1674,25 @@ static int map_internal_clock(struct mlx4_dev *dev)
return 0;
}

+int mlx4_get_internal_clock_params(struct mlx4_dev *dev,
+ struct mlx4_clock_params *params)
+{
+ struct mlx4_priv *priv = mlx4_priv(dev);
+
+ if (mlx4_is_slave(dev))
+ return -ENOTSUPP;
+
+ if (!params)
+ return -EINVAL;
+
+ params->bar = priv->fw.clock_bar;
+ params->offset = priv->fw.clock_offset;
+ params->size = MLX4_CLOCK_SIZE;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mlx4_get_internal_clock_params);
+
static void unmap_internal_clock(struct mlx4_dev *dev)
{
struct mlx4_priv *priv = mlx4_priv(dev);
diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index 83e80ab..f94984f 100644
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -829,6 +829,12 @@ struct mlx4_dev {
struct mlx4_vf_dev *dev_vfs;
};

+struct mlx4_clock_params {
+ u64 offset;
+ u8 bar;
+ u8 size;
+};
+
struct mlx4_eqe {
u8 reserved1;
u8 type;
@@ -1485,4 +1491,7 @@ int mlx4_ACCESS_PTYS_REG(struct mlx4_dev *dev,
enum mlx4_access_reg_method method,
struct mlx4_ptys_reg *ptys_reg);

+int mlx4_get_internal_clock_params(struct mlx4_dev *dev,
+ struct mlx4_clock_params *params);
+
#endif /* MLX4_DEVICE_H */
--
1.7.1