From 5567d4d9e7381230462a564d4f466177f3ba9dd5 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Wed, 2 Jun 2021 07:41:30 -0500 Subject: [PATCH 1/2] net: ipa: add support for inline checksum offload Starting with IPA v4.5, IP payload checksum offload is implemented differently. Prior to v4.5, the IPA hardware appends an rmnet_map_dl_csum_trailer structure to each packet if checksum offload is enabled in the download direction (modem->AP). In the upload direction (AP->modem) a rmnet_map_ul_csum_header structure is prepended before each sent packet. Starting with IPA v4.5, checksum offload is implemented using a single new rmnet_map_v5_csum_header structure which sits between the QMAP header and the packet data. The same header structure is used in both directions. The new header contains a header type (CSUM_OFFLOAD); a checksum flag; and a flag indicating whether any other headers follow this one. The checksum flag indicates whether the hardware should compute (and insert) the checksum on a sent packet. On a received packet the checksum flag indicates whether the hardware confirms the checksum value in the payload is correct. Signed-off-by: Alex Elder Signed-off-by: David S. Miller --- drivers/net/ipa/ipa_endpoint.c | 47 ++++++++++++++++++++++++++-------- drivers/net/ipa/ipa_reg.h | 1 + 2 files changed, 37 insertions(+), 11 deletions(-) diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c index ccc99ad983eb..03719fb6a15a 100644 --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -457,28 +457,34 @@ int ipa_endpoint_modem_exception_reset_all(struct ipa *ipa) static void ipa_endpoint_init_cfg(struct ipa_endpoint *endpoint) { u32 offset = IPA_REG_ENDP_INIT_CFG_N_OFFSET(endpoint->endpoint_id); + enum ipa_cs_offload_en enabled; u32 val = 0; /* FRAG_OFFLOAD_EN is 0 */ if (endpoint->data->checksum) { + enum ipa_version version = endpoint->ipa->version; + if (endpoint->toward_ipa) { u32 checksum_offset; - val |= u32_encode_bits(IPA_CS_OFFLOAD_UL, - CS_OFFLOAD_EN_FMASK); /* Checksum header offset is in 4-byte units */ checksum_offset = sizeof(struct rmnet_map_header); checksum_offset /= sizeof(u32); val |= u32_encode_bits(checksum_offset, CS_METADATA_HDR_OFFSET_FMASK); + + enabled = version < IPA_VERSION_4_5 + ? IPA_CS_OFFLOAD_UL + : IPA_CS_OFFLOAD_INLINE; } else { - val |= u32_encode_bits(IPA_CS_OFFLOAD_DL, - CS_OFFLOAD_EN_FMASK); + enabled = version < IPA_VERSION_4_5 + ? IPA_CS_OFFLOAD_DL + : IPA_CS_OFFLOAD_INLINE; } } else { - val |= u32_encode_bits(IPA_CS_OFFLOAD_NONE, - CS_OFFLOAD_EN_FMASK); + enabled = IPA_CS_OFFLOAD_NONE; } + val |= u32_encode_bits(enabled, CS_OFFLOAD_EN_FMASK); /* CS_GEN_QMB_MASTER_SEL is 0 */ iowrite32(val, endpoint->ipa->reg_virt + offset); @@ -498,6 +504,27 @@ static void ipa_endpoint_init_nat(struct ipa_endpoint *endpoint) iowrite32(val, endpoint->ipa->reg_virt + offset); } +static u32 +ipa_qmap_header_size(enum ipa_version version, struct ipa_endpoint *endpoint) +{ + u32 header_size = sizeof(struct rmnet_map_header); + + /* Without checksum offload, we just have the MAP header */ + if (!endpoint->data->checksum) + return header_size; + + if (version < IPA_VERSION_4_5) { + /* Checksum header inserted for AP TX endpoints only */ + if (endpoint->toward_ipa) + header_size += sizeof(struct rmnet_map_ul_csum_header); + } else { + /* Checksum header is used in both directions */ + header_size += sizeof(struct rmnet_map_v5_csum_header); + } + + return header_size; +} + /** * ipa_endpoint_init_hdr() - Initialize HDR endpoint configuration register * @endpoint: Endpoint pointer @@ -526,13 +553,11 @@ static void ipa_endpoint_init_hdr(struct ipa_endpoint *endpoint) u32 val = 0; if (endpoint->data->qmap) { - size_t header_size = sizeof(struct rmnet_map_header); enum ipa_version version = ipa->version; + size_t header_size; - /* We might supply a checksum header after the QMAP header */ - if (endpoint->toward_ipa && endpoint->data->checksum) - header_size += sizeof(struct rmnet_map_ul_csum_header); - val |= ipa_header_size_encoded(version, header_size); + header_size = ipa_qmap_header_size(version, endpoint); + val = ipa_header_size_encoded(version, header_size); /* Define how to fill fields in a received QMAP header */ if (!endpoint->toward_ipa) { diff --git a/drivers/net/ipa/ipa_reg.h b/drivers/net/ipa/ipa_reg.h index 286ea9634c49..b89dec5865a5 100644 --- a/drivers/net/ipa/ipa_reg.h +++ b/drivers/net/ipa/ipa_reg.h @@ -368,6 +368,7 @@ enum ipa_cs_offload_en { IPA_CS_OFFLOAD_NONE = 0x0, IPA_CS_OFFLOAD_UL = 0x1, /* Before IPA v4.5 (TX) */ IPA_CS_OFFLOAD_DL = 0x2, /* Before IPA v4.5 (RX) */ + IPA_CS_OFFLOAD_INLINE = 0x1, /* IPA v4.5 (TX and RX) */ }; /* Valid only for TX (IPA consumer) endpoints */ From d15ec1933309a4677d0a667738dc64329ec3fd69 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Wed, 2 Jun 2021 07:41:31 -0500 Subject: [PATCH 2/2] Revert "net: ipa: disable checksum offload for IPA v4.5+" This reverts commit c88c34fcf8f501d588c0a999aa7e51e18552c5f0. The RMNet driver now supports inline checksum offload. Signed-off-by: Alex Elder Signed-off-by: David S. Miller --- drivers/net/ipa/ipa_endpoint.c | 16 ---------------- 1 file changed, 16 deletions(-) diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c index 03719fb6a15a..07a81b73306f 100644 --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -88,11 +88,6 @@ static bool ipa_endpoint_data_valid_one(struct ipa *ipa, u32 count, if (ipa_gsi_endpoint_data_empty(data)) return true; - /* IPA v4.5+ uses checksum offload, not yet supported by RMNet */ - if (ipa->version >= IPA_VERSION_4_5) - if (data->endpoint.config.checksum) - return false; - if (!data->toward_ipa) { if (data->endpoint.filter_support) { dev_err(dev, "filtering not supported for " @@ -235,17 +230,6 @@ static bool ipa_endpoint_data_valid(struct ipa *ipa, u32 count, static bool ipa_endpoint_data_valid(struct ipa *ipa, u32 count, const struct ipa_gsi_endpoint_data *data) { - const struct ipa_gsi_endpoint_data *dp = data; - enum ipa_endpoint_name name; - - if (ipa->version < IPA_VERSION_4_5) - return true; - - /* IPA v4.5+ uses checksum offload, not yet supported by RMNet */ - for (name = 0; name < count; name++, dp++) - if (data->endpoint.config.checksum) - return false; - return true; }