| Message ID | 20220314195655.1183873-1-stijn@linux-ipv6.be |
|---|---|
| State | Accepted |
| Delegated to: | Stijn Tintel |
| Headers | show |
| Series | kernel: enable SERIAL_8250_16550A_VARIANTS | expand |
Hi, Stijn, On Mon, 14 Mar 2022 at 19:59, Stijn Tintel <stijn@linux-ipv6.be> wrote: > > Kernel 5.6 introduced a new config symbol SERIAL_8250_16550A_VARIANTS. > In kernel 5.8, this symbol was changed to default to on on !x86, as some > embedded devices still use 16650A variants. Let's play safe here and > enable this symbol in the generic config, to avoid others from running > into this problem and having to spend several hours trying to bisect > this problem. While we could disable the symbol in the x86 target > configs, a 20ms boot time reduction really isn't worth the time wasted > on bisecting this issue. > > Matt discovered this problem while working on adding support for the > WatchGuard Firebox M200 to the qoriq target, where it caused some > characters to be missing on the console output. > > Reported-by: Matt Fawcett <mattytap@icloud.com> > Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be> [patch snipped] Seems sensible to me. Reviewed-by: Rui Salvaterra <rsalvaterra@gmail.com> Cheers, Rui
diff --git a/target/linux/generic/config-5.10 b/target/linux/generic/config-5.10 index ca93b5f269..5f762529f0 100644 --- a/target/linux/generic/config-5.10 +++ b/target/linux/generic/config-5.10 @@ -5313,7 +5313,7 @@ CONFIG_SELECT_MEMORY_MODEL=y # CONFIG_SENSORS_XGENE is not set # CONFIG_SENSORS_ZL6100 is not set CONFIG_SERIAL_8250=y -# CONFIG_SERIAL_8250_16550A_VARIANTS is not set +CONFIG_SERIAL_8250_16550A_VARIANTS=y # CONFIG_SERIAL_8250_ACCENT is not set # CONFIG_SERIAL_8250_ASPEED_VUART is not set # CONFIG_SERIAL_8250_BOCA is not set
Kernel 5.6 introduced a new config symbol SERIAL_8250_16550A_VARIANTS. In kernel 5.8, this symbol was changed to default to on on !x86, as some embedded devices still use 16650A variants. Let's play safe here and enable this symbol in the generic config, to avoid others from running into this problem and having to spend several hours trying to bisect this problem. While we could disable the symbol in the x86 target configs, a 20ms boot time reduction really isn't worth the time wasted on bisecting this issue. Matt discovered this problem while working on adding support for the WatchGuard Firebox M200 to the qoriq target, where it caused some characters to be missing on the console output. Reported-by: Matt Fawcett <mattytap@icloud.com> Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be> --- target/linux/generic/config-5.10 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)