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 <[email protected]>
---
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 ccc99ad983eb5..03719fb6a15a4 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 286ea9634c49d..b89dec5865a5b 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 */
--
2.27.0