On 4/26/2022 1:00 AM, Sergey Ryazanov wrote:
On Tue, Apr 26, 2022 at 10:30 AM Ilpo Järvinen
<ilpo.jarvinen@xxxxxxxxxxxxxxx> wrote:
On Tue, 26 Apr 2022, Sergey Ryazanov wrote:
On Fri, Apr 8, 2022 at 1:37 AM Ricardo Martinez
<ricardo.martinez@xxxxxxxxxxxxxxx> wrote:
Data Path Modem AP Interface (DPMAIF) HIF layer provides methods
for initialization, ISR, control and event handling of TX/RX flows.
DPMAIF TX
Exposes the 'dmpaif_tx_send_skb' function which can be used by the
network device to transmit packets.
The uplink data management uses a Descriptor Ring Buffer (DRB).
First DRB entry is a message type that will be followed by 1 or more
normal DRB entries. Message type DRB will hold the skb information
and each normal DRB entry holds a pointer to the skb payload.
DPMAIF RX
The downlink buffer management uses Buffer Address Table (BAT) and
Packet Information Table (PIT) rings.
The BAT ring holds the address of skb data buffer for the HW to use,
while the PIT contains metadata about a whole network packet including
a reference to the BAT entry holding the data buffer address.
The driver reads the PIT and BAT entries written by the modem, when
reaching a threshold, the driver will reload the PIT and BAT rings.
Signed-off-by: Haijun Liu <haijun.liu@xxxxxxxxxxxx>
Signed-off-by: Chandrashekar Devegowda <chandrashekar.devegowda@xxxxxxxxx>
Co-developed-by: Ricardo Martinez <ricardo.martinez@xxxxxxxxxxxxxxx>
Signed-off-by: Ricardo Martinez <ricardo.martinez@xxxxxxxxxxxxxxx>
From a WWAN framework perspective:
Reviewed-by: Loic Poulain <loic.poulain@xxxxxxxxxx>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@xxxxxxxxx>
and a small question below.
diff --git a/drivers/net/wwan/t7xx/t7xx_hif_dpmaif_rx.c b/drivers/net/wwan/t7xx/t7xx_hif_dpmaif_rx.c
...
+static bool t7xx_alloc_and_map_skb_info(const struct dpmaif_ctrl *dpmaif_ctrl,
+ const unsigned int size, struct dpmaif_bat_skb *cur_skb)
+{
+ dma_addr_t data_bus_addr;
+ struct sk_buff *skb;
+ size_t data_len;
+
+ skb = __dev_alloc_skb(size, GFP_KERNEL);
+ if (!skb)
+ return false;
+
+ data_len = skb_end_pointer(skb) - skb->data;
Earlier you use a nice t7xx_skb_data_area_size() function here, but
now you opencode it. Is it a consequence of t7xx_common.h removing?
I would even encourage you to make this function common and place it
into include/linux/skbuff.h with a dedicated patch and call it
something like skb_data_size(). Surprisingly, there is no such helper
function in the kernel, and several other drivers will benefit from
it:
I agree other than the name. IMHO, skb_data_size sounds too much "data
size" which it exactly isn't but just how large the memory area is (we
already have "datalen" anyway and on language level, those two don't sound
different at all). The memory area allocated may or may not have actual
data in it, I suggested adding "area" into it.
I agree, using the "area" word in the helper name gives more clue
about its purpose, thanks.
Sounds good. I'll add a patch to introduce skb_data_area_size(),
I'm not planning to update other drivers to use it, at least in this series.
Please let me know if you think otherwise.
