Re: [PATCH net-next V6] net/mlx5: Improve write-combining test reliability for ARM64 Grace CPUs
From: Paolo Abeni <pabeni@redhat.com>
Date: 2025-10-01 09:28:16
Also in:
linux-arch, linux-patches, linux-rdma, linux-s390, lkml, llvm
Hi, On 9/28/25 11:08 PM, Tariq Toukan wrote:
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/wc.c b/drivers/net/ethernet/mellanox/mlx5/core/wc.c index 999d6216648a..c281153bd411 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/wc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/wc.c@@ -7,6 +7,10 @@ #include "mlx5_core.h" #include "wq.h" +#if IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && IS_ENABLED(CONFIG_ARM64) +#include <asm/neon.h> +#endif + #define TEST_WC_NUM_WQES 255 #define TEST_WC_LOG_CQ_SZ (order_base_2(TEST_WC_NUM_WQES)) #define TEST_WC_SQ_LOG_WQ_SZ TEST_WC_LOG_CQ_SZ@@ -255,6 +259,27 @@ static void mlx5_wc_destroy_sq(struct mlx5_wc_sq *sq) mlx5_wq_destroy(&sq->wq_ctrl); } +static void mlx5_iowrite64_copy(struct mlx5_wc_sq *sq, __be32 mmio_wqe[16], + size_t mmio_wqe_size, unsigned int offset) +{ +#if IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && IS_ENABLED(CONFIG_ARM64) + if (cpu_has_neon()) { + kernel_neon_begin(); + asm volatile + (".arch_extension simd;\n\t"
Here I'm observing build errors with aarch64-linux-gnu-gcc 12.1.1 20220507 (Red Hat Cross 12.1.1-1): /tmp/cchqHdeI.s: Assembler messages: /tmp/cchqHdeI.s:746: Error: unknown architectural extension `simd;' I can't reproduce the error on any recent compiler version via godbolt.org, so I *think* this should not block/be reverted for the MR, but could you please have a look soonish? Thanks, Paolo