From 899077791403ff7a2d8cfaa87bd1a82d729463e2 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 8 Dec 2015 16:32:27 +0100 Subject: netcp: try to reduce type confusion in descriptors The netcp driver produces tons of warnings when CONFIG_LPAE is enabled on ARM: drivers/net/ethernet/ti/netcp_core.c: In function 'netcp_tx_map_skb': drivers/net/ethernet/ti/netcp_core.c:1084:13: warning: passing argument 1 of 'set_words' from incompatible pointer type [-Wincompatible-pointer-types] This is the result of trying to pass a pointer to a dma_addr_t to a function that expects a u32 pointer to copy that into a DMA descriptor. Looking at that code in more detail to fix the warnings, I see multiple related problems: * The conversion functions are not endian-safe, as the DMA descriptors are almost certainly fixed-endian, but the CPU is not. * On 64-bit machines, passing a pointer through a u32 variable is a bug, accessing an indirect pointer as a u32 pointer even more so. * The handling of epib and psdata mixes native-endian and device-endian data. In this patch, I try to sort out the types for most accesses here, adding le32_to_cpu/cpu_to_le32 where appropriate, and passing pointers through two 32-bit words in the descriptor padding, to make it plausible that the driver does the right thing if compiled for big-endian or 64-bit systems. Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller --- include/linux/soc/ti/knav_dma.h | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'include/linux') diff --git a/include/linux/soc/ti/knav_dma.h b/include/linux/soc/ti/knav_dma.h index dad035c16d94..343c13ac4f71 100644 --- a/include/linux/soc/ti/knav_dma.h +++ b/include/linux/soc/ti/knav_dma.h @@ -144,17 +144,17 @@ struct knav_dma_cfg { * @psdata: Protocol specific */ struct knav_dma_desc { - u32 desc_info; - u32 tag_info; - u32 packet_info; - u32 buff_len; - u32 buff; - u32 next_desc; - u32 orig_len; - u32 orig_buff; - u32 epib[KNAV_DMA_NUM_EPIB_WORDS]; - u32 psdata[KNAV_DMA_NUM_PS_WORDS]; - u32 pad[4]; + __le32 desc_info; + __le32 tag_info; + __le32 packet_info; + __le32 buff_len; + __le32 buff; + __le32 next_desc; + __le32 orig_len; + __le32 orig_buff; + __le32 epib[KNAV_DMA_NUM_EPIB_WORDS]; + __le32 psdata[KNAV_DMA_NUM_PS_WORDS]; + __le32 pad[4]; } ____cacheline_aligned; #if IS_ENABLED(CONFIG_KEYSTONE_NAVIGATOR_DMA) -- cgit v1.2.3