From b337c0380f49fe1318d9a558ac0f8923dfe74801 Mon Sep 17 00:00:00 2001 From: Pekka Enberg Date: Sat, 8 Jan 2011 22:56:25 +0200 Subject: [PATCH] kvm,serial: Enable THRI bit in IIR register This patch enables the THRI ("transmission holding register empty") bit in the IIR register to make sure the guest doesn't think we have data waiting for it. Signed-off-by: Pekka Enberg --- tools/kvm/early_printk.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/kvm/early_printk.c b/tools/kvm/early_printk.c index a10d35846309..d5db3a12a523 100644 --- a/tools/kvm/early_printk.c +++ b/tools/kvm/early_printk.c @@ -24,6 +24,7 @@ #define IIR 2 #define UART_IIR_NO_INT 0x01 +#define UART_IIR_THRI 0x02 /* 16550 FIFO Control Register */ #define FCR 2 @@ -130,13 +131,13 @@ static bool serial8250_in(struct kvm *self, uint16_t port, void *data, int size, switch (offset) { case THR: - ioport__write8(data, 0x00); + /* TODO: input support */ break; case IER: ioport__write8(data, device.ier); break; case IIR: - ioport__write8(data, UART_IIR_NO_INT); + ioport__write8(data, UART_IIR_NO_INT | UART_IIR_THRI); break; case LCR: ioport__write8(data, device.lcr); -- 2.39.5