Re: [PATCH net-next V2] net/mlx5: Improve write-combining test reliability for ARM64 Grace CPUs
From: Jason Gunthorpe <jgg@nvidia.com>
Date: 2025-09-15 22:48:17
Also in:
linux-arch, linux-patches, linux-rdma, linux-s390, lkml, llvm
On Mon, Sep 15, 2025 at 03:27:58PM -0700, Nathan Chancellor wrote:
On Mon, Sep 15, 2025 at 03:18:59PM -0700, Nathan Chancellor wrote:quoted
On Mon, Sep 15, 2025 at 11:35:08AM +0300, Tariq Toukan wrote: ...quoted
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Makefile b/drivers/net/ethernet/mellanox/mlx5/core/Makefile index d77696f46eb5..06d0eb190816 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/Makefile +++ b/drivers/net/ethernet/mellanox/mlx5/core/Makefile@@ -176,3 +176,9 @@ mlx5_core-$(CONFIG_PCIE_TPH) += lib/st.o obj-$(CONFIG_MLX5_DPLL) += mlx5_dpll.o mlx5_dpll-y := dpll.o + +# +# NEON WC specific for mlx5 +# +mlx5_core-$(CONFIG_KERNEL_MODE_NEON) += lib/wc_neon_iowrite64_copy.o +FLAGS_lib/wc_neon_iowrite64_copy.o += $(CC_FLAGS_FPU)Does this work as is? I think this needs to be CFLAGS instead of FLAGS but I did not test to verify.Also, Documentation/core-api/floating-point.rst states that code should also use CFLAGS_REMOVE_ for CC_FLAGS_NO_FPU as well as adding CC_FLAGS_FPU. CFLAGS_REMOVE_lib/wc_neon_iowrite64_copy.o += $(CC_FLAGS_NO_FPU)
I wondered if you needed the seperate compilation unit at all since it it all done with inline assembly.. Since the makefile seems to have a typo, it suggests you don't need the compilation unit and it could just be a little inline protected by CONFIG_KERNEL_MODE_NEON. Jason