On Tue, 11 Mar 2025 at 15:37, Paolo Bonzini <pbonz...@redhat.com> wrote:
>
> The guest does not control whether characters are sent on the UART.
> Sending them before the guest happens to boot will now result in a
> "guest error" log entry that is only because of timing, even if the
> guest _would_ later setup the receiver correctly.
>
> This reverts commit abf2b6a028670bd2890bb3aee7e103fe53e4b0df, apart
> from adding the comment.
>
> Cc: Philippe Mathieu-Daudé <phi...@linaro.org>
> Cc: Peter Maydell <peter.mayd...@linaro.org>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> hw/char/pl011.c | 12 ++----------
> 1 file changed, 2 insertions(+), 10 deletions(-)
>
> diff --git a/hw/char/pl011.c b/hw/char/pl011.c
> index 23a9db8c57c..efca8baecd7 100644
> --- a/hw/char/pl011.c
> +++ b/hw/char/pl011.c
> @@ -85,7 +85,6 @@ DeviceState *pl011_create(hwaddr addr, qemu_irq irq,
> Chardev *chr)
> #define CR_OUT1 (1 << 12)
> #define CR_RTS (1 << 11)
> #define CR_DTR (1 << 10)
> -#define CR_RXE (1 << 9)
> #define CR_TXE (1 << 8)
> #define CR_LBE (1 << 7)
> #define CR_UARTEN (1 << 0)
> @@ -490,16 +489,9 @@ static int pl011_can_receive(void *opaque)
> unsigned fifo_depth = pl011_get_fifo_depth(s);
> unsigned fifo_available = fifo_depth - s->read_count;
>
> - if (!(s->cr & CR_UARTEN)) {
> - qemu_log_mask(LOG_GUEST_ERROR,
> - "PL011 receiving data on disabled UART\n");
> - }
> - if (!(s->cr & CR_RXE)) {
> - qemu_log_mask(LOG_GUEST_ERROR,
> - "PL011 receiving data on disabled RX UART\n");
> - }
> + /* Should check enable and return 0? */
We decided deliberately not to check the enable and return 0
here, as described in the commit message of abf2b6a028670bd:
we think there's too likely to be existing works-on-QEMU code
out there that doesn't ever set the enable bits.
Otherwise, yes, agreed with the revert.
thanks
-- PMM
