This makes the user interface a little hostile. People thing of an MTU of 1500 bytes, but the corresponding packet is really 1514 bytes (including the 14 byte Ethernet header). A more friendly solution would configure the MTU (as before), but then derive the packet buffer size by adding the MAC header length. Instead, we define the packet buffer size then derive the MTU.
The MTU is not common currency in networking. On the wire, the only real issue is the MSS which is derived from MTU by subtracting the IP header and TCP header sizes (for the case of TCP). Now it is derived for the PKTSIZE by subtracting the IP header, the TCP header, and the MAC header sizes. So we should be all good and without the recurring 14 byte error in MTU's and MSS's.
Squashed commit of the following:
Trivial update to fix some spacing issues.
net/: Rename several macros containing _MTU to _PKTSIZE.
net/: Rename CONFIG_NET_SLIP_MTU to CONFIG_NET_SLIP_PKTSIZE and similarly for CONFIG_NET_TUN_MTU. These are not the MTU which does not include the size of the link layer header. These are the full size of the packet buffer memory (minus any GUARD bytes).
net/: Rename CONFIG_NET_6LOWPAN_MTU to CONFIG_NET_6LOWPAN_PKTSIZE and similarly for CONFIG_NET_TUN_MTU. These are not the MTU which does not include the size of the link layer header. These are the full size of the packet buffer memory (minus any GUARD bytes).
net/: Rename CONFIG_NET_ETH_MTU to CONFIG_NET_ETH_PKTSIZE. This is not the MTU which does not include the size of the link layer header. This is the full size of the packet buffer memory (minus any GUARD bytes).
net/: Rename the file d_mtu in the network driver structure to d_pktsize. That value saved there is not the MTU. The packetsize is the memory large enough to hold the maximum packet PLUS the size of the link layer header. The MTU does not include the link layer header.
Fix a few typo/compilation problems.
net/: Remove all CONFIG_NET_xxx_TCP_RECVWNDO configuration variables. They were used only to initialize the d_recwndo of the network device structure which no longer exists.
net/: Remove the device TCP receive window field (d_recvwndo) from the device structure. That value is no longer retained, but is calculated dynamically.
Remove some dangling references to CONFIG_NET_TCP_RWND_CONTROL.
net/tcp: Take read-ahead throttling into account when calculating the TCP receive window size.
net/tcp: tcp_get_recvwindow() now returns the receive window size directly (vs. indirectly via the device structure).
net/tcp: Remove CONFIG_NET_TCP_RWND_CONTROL. TCP window algorithm is now trigged only by CONFIG_NET_TCP_READAHEAD.
arch/arm: Remove support for CONFIG_ARMV7M_CMNVECTOR. It is now the only vector support available. Also remove CONFIG_HAVE_CMNVECTOR. That no longer signifies anything."
arch/arm/src/stm32: This commit removes support for the dedicated vector handling from the STM32 architecture support. Only common vectors are now supported.
configs/stm32f4discovery/include/board.h: Add SPI DMA pins definitions to get CS43L22 audio DAC working
configs/stm32f4discovery/audio: Add board configuration for CS43L22 audio example
configs/stm32f4discovery: Update README
Squashed commit of the following:
configs/*/README.txt: Replace each occurrence of './configure.sh' with 'tools/configure.sh'
configs/*/README.txt: Remove 'cd ..' after each './configure.sh'
configs/*/README.txt: Remove 'cd -' after each './configure.sh'
configs/*/README.txt: Remove 'cd tools' before each './configure.sh'
configs/README.txt: Remove instruction to CD tools/ before running configure.sh.
Squashed commit of the following:
arch/arm/src/stm32: Add Kconfig options needed by the HCI UART. Various fixes to finally get a clean error free compile with no unexpected warnings.
arch/arm/src/stm32: In HCI UART, use spin_lock_irqsave() instead of enter_critical_section() whenever possible.
arch/arm/src/stm32: In HCI UART, fix up naming of configurations so that they are unique. Still needs Kconfig settings. Modify logic so that there can be multiple HCI UARTs, some supporting DMA and some not.
arch/arm/src/stm32: Integrate watermarks and software Rx flow control into the HCI UART driver.
arch/arm/src/stm32: Eliminate some HCI UART UART configuration options. Per the HCI UART spec, the link will b 8 data bits, no parity, 1 stop bit... Always.
arch/arm/src/stm32: Trivial cleanup
arch/arm/src/stm32: Fixes most initial compilation issues STM32 HCI UART driver. Still need to set up USART configuration parmeters for HCI UART
arch/arm/src/stm32: Completes first cut at STM32 HCI UART driver.
arch/arm/src/stm32: Completes most of read logic for HCI UART. Still needs to be able to block if no read data is available. Still missing write and flush logic.
drivers/wireless: Remove txenable from HCI UART methods. arch/arm/src/stm32: Reorganize some structures in HCI UART.
arch/arm/src/stm32: Still messaging the HCI uart driver.
arch/arm/src/stm32: Some trivial renaming.
arch/arm/src/stm32: A little more HCI-UART logic.
arch/arm/src/stm32: Initial setup to support HCI-UART. Little more than the serial driver with some name changes and a few things removed.
sched/: Convert legitimate uses of task_create() to nxtask_create(). Review handling of returned values from all uses of kthread_create() (as well as nxtask_create()).
graphics/: Review return values for all calls to kthread_start() because it no longer returns an errno.
drivers/: threads started by drivers should be kernel threads, not user tasks. Review return values for all calls to kthread_start() because it no longer returns an errno.
configs/: threads started by board bringup logic should be kernel threads, not user tasksi (part 2 of 2).
sched/task: Add nxtask_create(). Kthread_create() and nxtask_create() are internal OS functions and should not modify the errno variable. configs/: threads started by board bringup logic should be kernel threads, not user tasks.
configs/flipnclick-sam3x: Add support for the 4 user-controllable LEDs on the board.
configs/flipnclick-sam3x: Add board support for the Mikroe Flip&Click SAM3X.
configs/arduino-due: Update this old configuration so that it is structured a little more like recent board support.
