and start teaching subsystems about it.
The Atheros MIPS platforms don't guarantee any kind of FIFO consistency
with interrupts in hardware. So software needs to do a flush when it
receives an interrupt and before it calls the interrupt handler.
There are new ones for the QCA934x and QCA955x, so do a few things:
* Get rid of the individual ones (for ethernet and IP2);
* Create a mux and enum listing all the variations on DDR flushes;
* replace the uses of IP2 with the relevant one (which will typically
be "PCI" here);
* call the USB DDR flush before calling the real USB interrupt handlers;
* call the ethernet one upon receiving an interrupt that's for us,
rather than never calling it during operation.
Tested:
* QCA9558 (TP-Link archer c7 v2)
* AR9331 (Carambola 2)
TODO:
* PCI, USB, ethernet, etc need to do a double-check to see if the
interrupt was truely for them before doing the DDR. For now I
prefer "correct" over "fast".
* Initialise the MDIO clock to default to the reference clock;
* Add some code to allow the hints mechanism to allow setup of the GMAC
config block.
* Document how the switch is wired up internally.
Tested:
* AR9331 SoC (Carambola 2)
For all pre-AR933x chips, the frequency is just the APB frequency.
For the AR933x, the UART frequency is different but we just hacked around
it.
For the AR934x, there's a different PLL setting for these, so they have
to be broken out.
This was ported from the AR724x code and I think that also doesn't
quite work. I'll investigate that soon.
With this in place the system reset path works, so 'reset' from kdb
actually resets the SoC.
Tested:
* AP121 test board
CPUs.
The AR933x is a mips24k based SoC with an AR9380 series SoC on board,
two gigabit ethernet interfaces and an internal 10/100mbit ethernet
switch. There's also the normal interfaces (USB, ethernet, uart, GPIO.)
The downside? There's a non-ns8250 UART device.
With a very basic UART driver (not in this commit) the SoC is initialised
and boots up. I'll commit the UART code soon and then link it into the
general setup path.
This code is a re-implementation based from the Linux kernel / openwrt
AR933x support.
TODO:
* UART (obviously)
* All of the ethernet, USB and wifi SoC glue, including ethernet PLL
programming.
