On 11/05/2022 15:15, Roger Pau Monné wrote: > On Wed, May 11, 2022 at 03:59:28PM +0200, Marek Marczykowski-Górecki wrote: >> Intel LPSS has INTERRUPT_LINE set to 0xff by default, that is declared >> by the PCI Local Bus Specification Revision 3.0 (from 2004) as >> "unknown"/"no connection". Fallback to poll mode in this case. >> The 0xff handling is x86-specific, the surrounding code is guarded with >> CONFIG_X86 anyway. >> >> Signed-off-by: Marek Marczykowski-Górecki <marma...@invisiblethingslab.com> >> --- >> Changes in v4: >> - adjust log message, change it from WARNING to INFO >> - re-add x86 reference in the commit message >> Changes in v3: >> - change back to checking 0xff explicitly >> - adjust commit message, include spec reference >> - change warning to match the above >> Changes in v2: >> - add log message >> - extend commit message >> - code style fix >> --- >> xen/drivers/char/ns16550.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/xen/drivers/char/ns16550.c b/xen/drivers/char/ns16550.c >> index fb75cee4a13a..c0d65cff62fe 100644 >> --- a/xen/drivers/char/ns16550.c >> +++ b/xen/drivers/char/ns16550.c >> @@ -1238,6 +1238,13 @@ pci_uart_config(struct ns16550 *uart, bool_t >> skip_amt, unsigned int idx) >> pci_conf_read8(PCI_SBDF(0, b, d, f), >> PCI_INTERRUPT_LINE) : 0; >> >> + if ( uart->irq == 0xff ) >> + uart->irq = 0; >> + if ( !uart->irq ) >> + printk(XENLOG_INFO >> + "ns16550: %pp no legacy IRQ %d, using poll >> mode\n", >> + &PCI_SBDF(0, b, d, f), uart->irq); > There's no point in printing ->irq as it will be 0 or else the message > won't be printed. > > With that fixed: > > Reviewed-by: Roger Pau Monné <roger....@citrix.com>
TBH, can be fixed on commit, save another round of patching. ~Andrew
