According to the hardware manual, when the Poll command is issued, the
byte returned by the I/O read is 1 in Bit 7 when there is an interrupt,
and the highest priority binary code in Bits 2:0. The current pic
simulation code is not implemented strictly according to the above
expression.
Fix the implementation of poll mode in pic simulation by pic_intack,
and remove redundant pic_poll_read code.
Signed-off-by: Jinliang Zheng <alexjlzheng@xxxxxxxxxxx>
---
arch/x86/kvm/i8259.c | 29 ++++++-----------------------
1 file changed, 6 insertions(+), 23 deletions(-)
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 4756bcb5724f..bc5b758e8f73 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -397,35 +397,18 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
}
}
-static u32 pic_poll_read(struct kvm_kpic_state *s, u32 addr1)
-{
- int ret;
-
- ret = pic_get_irq(s);
- if (ret >= 0) {
- if (addr1 >> 7) {
- s->pics_state->pics[0].isr &= ~(1 << 2);
- s->pics_state->pics[0].irr &= ~(1 << 2);
- }
- s->irr &= ~(1 << ret);
- pic_clear_isr(s, ret);
- if (addr1 >> 7 || ret != 2)
- pic_update_irq(s->pics_state);
- } else {
- ret = 0x07;
- pic_update_irq(s->pics_state);
- }
-
- return ret;
-}
-
static u32 pic_ioport_read(void *opaque, u32 addr)
{
struct kvm_kpic_state *s = opaque;
int ret;
if (s->poll) {
- ret = pic_poll_read(s, addr);
+ ret = pic_get_irq(s);
+ if (ret >= 0) {
+ pic_intack(s, ret);
+ ret |= 0x80;
+ } else
+ ret = 0;
s->poll = 0;
} else
if ((addr & 1) == 0)
--
2.37.3
