diff options
| author | Alex Elder <elder@linaro.org> | 2020-06-11 14:48:33 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-06-11 18:39:08 -0700 |
| commit | f330fda331d276464baec8ba938d031b4adcf5c7 (patch) | |
| tree | 905d63da5236dd5d1bb37ddf48fd9ebd04598e0b /drivers | |
| parent | 636edeaad5577b6023f0de2b98a010d1cea73607 (diff) | |
| download | linux-f330fda331d276464baec8ba938d031b4adcf5c7.tar.bz2 | |
net: ipa: header pad field only valid for AP->modem endpoint
Only QMAP endpoints should be configured to find a pad size field
within packet headers. They are found in the first byte of the QMAP
header (and the hardware fills only the 6 bits in that byte that
constitute the pad_len field).
The RMNet driver assumes the pad_len field is valid for received
packets, so we want to ensure the pad_len field is filled in that
case. That driver also assumes the length in the QMAP header
includes the pad bytes.
The RMNet driver does *not* pad the packets it sends, so the pad_len
field can be ignored.
Fix ipa_endpoint_init_hdr_ext() so it only marks the pad field
offset valid for QMAP RX endpoints, and in that case indicates
that the length field in the header includes the pad bytes.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/ipa/ipa_endpoint.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c index bf3e8ced3ee0..9f50d0d11704 100644 --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -467,7 +467,7 @@ static void ipa_endpoint_init_hdr(struct ipa_endpoint *endpoint) header_size += sizeof(struct rmnet_map_ul_csum_header); val |= u32_encode_bits(header_size, HDR_LEN_FMASK); - /* Define how to fill mux_id in a received QMAP header */ + /* Define how to fill fields in a received QMAP header */ if (!endpoint->toward_ipa) { u32 off; /* Field offset within header */ @@ -499,10 +499,21 @@ static void ipa_endpoint_init_hdr_ext(struct ipa_endpoint *endpoint) u32 val = 0; val |= HDR_ENDIANNESS_FMASK; /* big endian */ - val |= HDR_TOTAL_LEN_OR_PAD_VALID_FMASK; - /* HDR_TOTAL_LEN_OR_PAD is 0 (pad, not total_len) */ + + /* A QMAP header contains a 6 bit pad field at offset 0. The RMNet + * driver assumes this field is meaningful in packets it receives, + * and assumes the header's payload length includes that padding. + * The RMNet driver does *not* pad packets it sends, however, so + * the pad field (although 0) should be ignored. + */ + if (endpoint->data->qmap && !endpoint->toward_ipa) { + val |= HDR_TOTAL_LEN_OR_PAD_VALID_FMASK; + /* HDR_TOTAL_LEN_OR_PAD is 0 (pad, not total_len) */ + val |= HDR_PAYLOAD_LEN_INC_PADDING_FMASK; + /* HDR_TOTAL_LEN_OR_PAD_OFFSET is 0 */ + } + /* HDR_PAYLOAD_LEN_INC_PADDING is 0 */ - /* HDR_TOTAL_LEN_OR_PAD_OFFSET is 0 */ if (!endpoint->toward_ipa) val |= u32_encode_bits(pad_align, HDR_PAD_TO_ALIGNMENT_FMASK); |