| Message ID | 20210128033655.1029577-1-iris@modwiz.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | hw/char/exynos4210_uart: Fix buffer size reporting with FIFO disabled | expand |
On Thu, 28 Jan 2021 at 03:36, Iris Johnson <iris@modwiz.com> wrote: > > Currently the Exynos 4210 UART code always reports available FIFO space > when the backend checks for buffer space. When the FIFO is disabled this > is behavior causes the backend chardev code to replace the data before the > guest can read it. > > This patch changes adds the logic to report the capacity properly when the > FIFO is not being used. > > Buglink: https://bugs.launchpad.net/qemu/+bug/1913344 > Signed-off-by: Iris Johnson <iris@modwiz.com> > --- > hw/char/exynos4210_uart.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) Applied to target-arm.next, thanks. -- PMM
diff --git a/hw/char/exynos4210_uart.c b/hw/char/exynos4210_uart.c index 6361df2ad3..9b21d201b3 100644 --- a/hw/char/exynos4210_uart.c +++ b/hw/char/exynos4210_uart.c @@ -553,7 +553,11 @@ static int exynos4210_uart_can_receive(void *opaque) { Exynos4210UartState *s = (Exynos4210UartState *)opaque; - return fifo_empty_elements_number(&s->rx); + if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) { + return fifo_empty_elements_number(&s->rx); + } else { + return !(s->reg[I_(UTRSTAT)] & UTRSTAT_Rx_BUFFER_DATA_READY); + } } static void exynos4210_uart_receive(void *opaque, const uint8_t *buf, int size)
Currently the Exynos 4210 UART code always reports available FIFO space when the backend checks for buffer space. When the FIFO is disabled this is behavior causes the backend chardev code to replace the data before the guest can read it. This patch changes adds the logic to report the capacity properly when the FIFO is not being used. Buglink: https://bugs.launchpad.net/qemu/+bug/1913344 Signed-off-by: Iris Johnson <iris@modwiz.com> --- hw/char/exynos4210_uart.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)