Hi,
I am running Debian on a Netgear WGT634U with a ~mainline 2.6.37 kernel.
Upon upgrading from .32 I noticed this patch:-
diff --git a/arch/mips/bcm47xx/setup.c b/arch/mips/bcm47xx/setup.c
index 87a3055..c95f90b 100644
--- a/arch/mips/bcm47xx/setup.c
+++ b/arch/mips/bcm47xx/setup.c
@@ -169,12 +169,28 @@ static int bcm47xx_get_invariants(struct ssb_bus
*bus,
void __init plat_mem_setup(void)
{
int err;
+ char buf[100];
+ struct ssb_mipscore *mcore;
err = ssb_bus_ssbbus_register(&ssb_bcm47xx, SSB_ENUM_BASE,
bcm47xx_get_invariants);
if (err)
panic("Failed to initialize SSB bus (err %d)\n", err);
+ mcore = &ssb_bcm47xx.mipscore;
+ if (nvram_getenv("kernel_args", buf, sizeof(buf)) >= 0) {
+ if (strstr(buf, "console=ttyS1")) {
+ struct ssb_serial_port port;
+
+ printk(KERN_DEBUG "Swapping serial ports!\n");
+ /* swap serial ports */
+ memcpy(&port, &mcore->serial_ports[0], sizeof(port));
+ memcpy(&mcore->serial_ports[0], &mcore->serial_ports[1],
+ sizeof(port));
+ memcpy(&mcore->serial_ports[1], &port, sizeof(port));
+ }
A WGT634U only has the header on the second serial port, this is where
CFE outputs it's console by default, and where I have my serial cable
attached.
If I specify console=ttyS1, then the above kicks in and the serial port I
am attached to becomes ttyS0 early in the boot process, and I loose
console output. If I specify console=ttyS0, the above doesn't do anything
so the kernel continues to use the unattached serial port. Either way I
cannot get any console output without some hacking.
Currently I have removed the block, specified "console=ttyS1" in the
commandline, and this gives me working console all the way through boot.
I'm happy to test/supply any further patches, solutions I can think of
are:-
* Remove it entirely: I think this code has it's origins in OpenWRT
code that swapped ports so the userland didn't have to use ttyS1 for a
bunch of devices, ttyS0 for another. It's certainly not required to get
console output on my device, not tested any other variants of this
platform.
* Invert the strstr logic, so that the swap happens if I don't specify
ttyS1 as my console. Then regardless of whether I use ttyS0 or ttyS1, I
get a console.
* Have a more explict "swap_serial_ports" kernel parameter
Cheers,
--
Jamie Lentin
