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Fixes: f2ff5d6628b3 ("ns16550: enable PCI serial card usage") Signed-off-by: Roger Pau Monn=C3=A9 Reviewed-by: Jan Beulich --- Changes since v1: - Adjusted over previous fixes. --- xen/drivers/char/ns16550.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/xen/drivers/char/ns16550.c b/xen/drivers/char/ns16550.c index d05dc506ed9c..d16e447c0e76 100644 --- a/xen/drivers/char/ns16550.c +++ b/xen/drivers/char/ns16550.c @@ -283,14 +283,19 @@ static int cf_check ns16550_getc(struct serial_port *= port, char *pc) static void pci_serial_early_init(struct ns16550 *uart) { #ifdef NS16550_PCI + uint16_t cmd; + if ( !uart->ps_bdf_enable ) return; =20 + cmd =3D pci_conf_read16(PCI_SBDF(0, uart->ps_bdf[0], uart->ps_bdf[1], + uart->ps_bdf[2]), PCI_COMMAND); + if ( uart->io_base >=3D 0x10000 ) { pci_conf_write16(PCI_SBDF(0, uart->ps_bdf[0], uart->ps_bdf[1], uart->ps_bdf[2]), - PCI_COMMAND, PCI_COMMAND_MEMORY); + PCI_COMMAND, cmd | PCI_COMMAND_MEMORY); return; } =20 @@ -307,7 +312,7 @@ static void pci_serial_early_init(struct ns16550 *uart) uart->io_base | PCI_BASE_ADDRESS_SPACE_IO); pci_conf_write16(PCI_SBDF(0, uart->ps_bdf[0], uart->ps_bdf[1], uart->ps_bdf[2]), - PCI_COMMAND, PCI_COMMAND_IO); + PCI_COMMAND, cmd | PCI_COMMAND_IO); #endif } =20 --=20 2.51.0