From d69e3bcf79764ed833e0cc6e0645dc87589cec22 Mon Sep 17 00:00:00 2001 From: Matan Barak Date: Tue, 15 Dec 2015 20:30:13 +0200 Subject: [PATCH] IB/mlx5: Mmap the HCA's core clock register to user-space In order to read the HCA's current cycles register, we need to map it to user-space. Add support to map this register via mmap command. Signed-off-by: Matan Barak Reviewed-by: Moshe Lazer Signed-off-by: Doug Ledford --- drivers/infiniband/hw/mlx5/main.c | 28 ++++++++++++++++++++++++++++ drivers/infiniband/hw/mlx5/mlx5_ib.h | 4 +++- 2 files changed, 31 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c index a3ae9ccde460..602f067c14cc 100644 --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -1023,6 +1023,34 @@ static int mlx5_ib_mmap(struct ib_ucontext *ibcontext, struct vm_area_struct *vm case MLX5_IB_MMAP_GET_CONTIGUOUS_PAGES: return -ENOSYS; + case MLX5_IB_MMAP_CORE_CLOCK: + { + phys_addr_t pfn; + + if (vma->vm_end - vma->vm_start != PAGE_SIZE) + return -EINVAL; + + if (vma->vm_flags & (VM_WRITE | VM_EXEC)) + return -EPERM; + + /* Don't expose to user-space information it shouldn't have */ + if (PAGE_SIZE > 4096) + return -EOPNOTSUPP; + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + pfn = (dev->mdev->iseg_base + + offsetof(struct mlx5_init_seg, internal_timer_h)) >> + PAGE_SHIFT; + if (io_remap_pfn_range(vma, vma->vm_start, pfn, + PAGE_SIZE, vma->vm_page_prot)) + return -EAGAIN; + + mlx5_ib_dbg(dev, "mapped internal timer at 0x%lx, PA 0x%llx\n", + vma->vm_start, + (unsigned long long)pfn << PAGE_SHIFT); + break; + } + default: return -EINVAL; } diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h index b2a66432b865..1303487ffe6b 100644 --- a/drivers/infiniband/hw/mlx5/mlx5_ib.h +++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h @@ -65,7 +65,9 @@ enum { enum mlx5_ib_mmap_cmd { MLX5_IB_MMAP_REGULAR_PAGE = 0, - MLX5_IB_MMAP_GET_CONTIGUOUS_PAGES = 1, /* always last */ + MLX5_IB_MMAP_GET_CONTIGUOUS_PAGES = 1, + /* 5 is chosen in order to be compatible with old versions of libmlx5 */ + MLX5_IB_MMAP_CORE_CLOCK = 5, }; enum { -- 2.20.1