From c597897b08cb56e6a8b240245c074d43d1fde735 Mon Sep 17 00:00:00 2001 From: Subash Abhinov Kasiviswanathan Date: Sun, 7 Jan 2018 11:36:36 -0700 Subject: [PATCH] net: qualcomm: rmnet: Define the MAPv4 packet formats The MAPv4 packet format adds support for RX / TX checksum offload. For a bi-directional UDP stream at a rate of 570 / 146 Mbps, roughly 10% CPU cycles are saved. For receive path, there is a checksum trailer appended to the end of the MAP packet. The valid field indicates if hardware has computed the checksum. csum_start_offset indicates the offset from the start of the IP header from which hardware has computed checksum. csum_length is the number of bytes over which the checksum was computed and the resulting value is csum_value. In the transmit path, a header is appended between the end of the MAP header and the start of the IP packet. csum_start_offset is the offset in bytes from which hardware will compute the checksum if the csum_enabled bit is set. udp_ip4_ind indicates if the checksum value of 0 is valid or not. csum_insert_offset is the offset from the csum_start_offset where hardware will insert the computed checksum. The use of this additional packet format for checksum offload is explained in subsequent patches. Signed-off-by: Subash Abhinov Kasiviswanathan Signed-off-by: David S. Miller --- drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h | 16 ++++++++++++++++ drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h | 2 ++ 2 files changed, 18 insertions(+) diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h index ef0eff2..50c50cd 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h @@ -47,6 +47,22 @@ struct rmnet_map_header { u16 pkt_len; } __aligned(1); +struct rmnet_map_dl_csum_trailer { + u8 reserved1; + u8 valid:1; + u8 reserved2:7; + u16 csum_start_offset; + u16 csum_length; + __be16 csum_value; +} __aligned(1); + +struct rmnet_map_ul_csum_header { + __be16 csum_start_offset; + u16 csum_insert_offset:14; + u16 udp_ip4_ind:1; + u16 csum_enabled:1; +} __aligned(1); + #define RMNET_MAP_GET_MUX_ID(Y) (((struct rmnet_map_header *) \ (Y)->data)->mux_id) #define RMNET_MAP_GET_CD_BIT(Y) (((struct rmnet_map_header *) \ diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h index d214280..de0143e 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h @@ -21,6 +21,8 @@ /* Constants */ #define RMNET_INGRESS_FORMAT_DEAGGREGATION BIT(0) #define RMNET_INGRESS_FORMAT_MAP_COMMANDS BIT(1) +#define RMNET_INGRESS_FORMAT_MAP_CKSUMV4 BIT(2) +#define RMNET_EGRESS_FORMAT_MAP_CKSUMV4 BIT(3) /* Replace skb->dev to a virtual rmnet device and pass up the stack */ #define RMNET_EPMODE_VND (1) -- 2.7.4