Commit Graph

10 Commits

Author SHA1 Message Date
Guenter Roeck 65e9f27f22 bcm2835_aux: Swap RX and TX interrupt assignments
RX and TX interrupt bits were reversed, resulting in an endless sequence
of serial interupts in the emulated system and the following repeated
error message when booting Linux.

serial8250: too much work for irq61

This results in a boot failure most of the time.

Qemu command line used to reproduce the problem:

	qemu-system-aarch64 -M raspi3 -m 1024 \
	-kernel arch/arm64/boot/Image \
	--append "rdinit=/sbin/init console=ttyS1,115200"
	-initrd rootfs.cpio \
	-dtb arch/arm64/boot/dts/broadcom/bcm2837-rpi-3-b.dtb \
	-nographic -monitor null -serial null -serial stdio

This is with arm64:defconfig. The root file system was generated using
buildroot.

NB that this error likely arises from an erratum in the
BCM2835 datasheet where the TX and RX bits were swapped
in the AU_MU_IER_REG description (but correct for IIR):
 https://elinux.org/BCM2835_datasheet_errata#p12

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Message-id: 1529355846-25102-1-git-send-email-linux@roeck-us.net
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: added NB about datasheet]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-07-16 17:18:42 +01:00
Anton Nefedov 81517ba37a char: add backend hotswap handler
Frontends should have an interface to setup the handler of a backend change.
The interface will be used in the next commits

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1499342940-56739-3-git-send-email-anton.nefedov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 11:04:33 +02:00
Marc-André Lureau 39ab61c6d0 char: remove explicit_fe_open, use a set_handlers argument
No need to keep explicit_fe_open around if it affects only a
qemu_chr_fe_set_handlers(). Use an additional argument instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-24-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau fa394ed625 char: make some qemu_chr_fe skip if no driver
In most cases, front ends do not care about the side effect of
CharBackend, so we can simply skip the checks and call the qemu_chr_fe
functions even without associated CharDriver.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-20-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:21 +02:00
Marc-André Lureau 5345fdb446 char: use qemu_chr_fe* functions with CharBackend argument
This also switches from qemu_chr_add_handlers() to
qemu_chr_fe_set_handlers(). Note that qemu_chr_fe_set_handlers() now
takes the focus when fe_open (qemu_chr_add_handlers() did take the
focus)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-16-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:21 +02:00
Marc-André Lureau 7fa47e2a80 char: rename some frontend functions
qemu_chr_accept_input() and qemu_chr_disconnect() are only used by
frontend, so use qemu_chr_fe prefix.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-14-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:20 +02:00
Marc-André Lureau becdfa00cf char: replace PROP_CHR with CharBackend
Store the property in a CharBackend instead of CharDriverState*.  This
also replace systematically chr by chr.chr to access the
CharDriverState*. The following patches will replace it with calls to
qemu_chr_fe CharBackend functions.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:20 +02:00
Daniel P. Berrange 6ab3fc32ea hw: replace most use of qemu_chr_fe_write with qemu_chr_fe_write_all
The qemu_chr_fe_write method will return -1 on EAGAIN if the
chardev backend write would block. Almost no callers of the
qemu_chr_fe_write() method check the return value, instead
blindly assuming data was successfully sent. In most cases
this will lead to silent data loss on interactive consoles,
but in some cases (eg RNG EGD) it'll just cause corruption
of the protocol being spoken.

We unfortunately can't fix the virtio-console code, due to
a bug in the Linux guest drivers, which would cause the
entire Linux kernel to hang if we delay processing of the
incoming data in any way. Fixing this requires first fixing
the guest driver to not hold spinlocks while writing to the
hvc device backend.

Fixes bug: https://bugs.launchpad.net/qemu/+bug/1586756

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1473170165-540-4-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13 19:09:42 +02:00
Paolo Bonzini 03dd024ff5 hw: explicitly include qemu/log.h
Move the inclusion out of hw/hw.h, most files do not need it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Andrew Baumann 97398d900c bcm2835_aux: add emulation of BCM2835 AUX (aka UART1) block
At present only the core UART functions (data path for tx/rx) are
implemented, which is enough for UEFI to boot. The following
features/registers are unimplemented:
  * Line/modem control
  * Scratch register
  * Extra control
  * Baudrate
  * SPI interfaces

Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1457467526-8840-3-git-send-email-Andrew.Baumann@microsoft.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-03-16 17:42:18 +00:00