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authorPeter Maydell <peter.maydell@linaro.org>2018-02-13 18:24:07 +0000
committerPeter Maydell <peter.maydell@linaro.org>2018-02-13 18:24:08 +0000
commitbec9c64ef7be8063f1192608b83877bc5c9ea217 (patch)
treee3dd26e9a874b7a8ee86d977ed51146f06312035 /docs
parentb734ed9de10dbf10a873ae4b44cb1c13f59213d0 (diff)
parent7524a39d8c7c9ff54504cfeb784909e4f49d6f30 (diff)
Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
* CAN bus (will be under network maintainner) * scsi-block opblockers (myself) * Dirty log bitmap cleanup (myself) * SDHCI improvements and tests (Philippe) * HAX support for larger guest sizese (Yu Ning) # gpg: Signature made Tue 13 Feb 2018 15:37:14 GMT # gpg: using RSA key BFFBD25F78C7AE83 # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * remotes/bonzini/tags/for-upstream: (48 commits) travis: use libgcc-4.8-dev (libgcc-6-dev is not available on Ubuntu 14.04) memory: unify loops to sync dirty log bitmap memory: hide memory_region_sync_dirty_bitmap behind DirtyBitmapSnapshot memory: remove memory_region_test_and_clear_dirty g364fb: switch to using DirtyBitmapSnapshot sdhci: add Spec v4.2 register definitions sdhci: add a check_capab_v3() qtest sdhci: check Spec v3 capabilities qtest hw/arm/xilinx_zynqmp: enable the UHS-I mode hw/arm/xilinx_zynqmp: fix the capabilities/spec version to match the datasheet hw/arm/fsl-imx6: implement SDHCI Spec. v3 hw/arm/bcm2835_peripherals: change maximum block size to 1kB hw/arm/bcm2835_peripherals: implement SDHCI Spec v3 sdhci: implement CMD/DAT[] fields in the Present State register sdhci: implement UHS-I voltage switch sdbus: add trace events sdhci: implement the Host Control 2 register (tuning sequence) sdhci: rename the hostctl1 register sdhci: add support for v3 capabilities hw/arm/xilinx_zynq: fix the capabilities register to match the datasheet ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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+QEMU CAN bus emulation support
+==============================
+
+The CAN bus emulation provides mechanism to connect multiple
+emulated CAN controller chips together by one or multiple CAN busses
+(the controller device "canbus" parameter). The individual busses
+can be connected to host system CAN API (at this time only Linux
+SocketCAN is supported).
+
+The concept of busses is generic and different CAN controllers
+can be implemented for it but at this time only SJA1000 chip
+controller is implemented.
+
+The PCI addon card hardware has been selected as the first CAN
+interface to implement because such device can be easily connected
+to systems with different CPU architectures (x86, PowerPC, ARM, etc.).
+
+The project has been initially started in frame of RTEMS GSoC 2013
+slot by Jin Yang under our mentoring The initial idea was to provide generic
+CAN subsystem for RTEMS. But lack of common environment for code and RTEMS
+testing lead to goal change to provide environment which provides complete
+emulated environment for testing and RTEMS GSoC slot has been donated
+to work on CAN hardware emulation on QEMU.
+
+Examples how to use CAN emulation
+=================================
+
+When QEMU with CAN PCI support is compiled then one of the next
+CAN boards can be selected
+
+ (1) CAN bus Kvaser PCI CAN-S (single SJA1000 channel) boad. QEMU startup options
+ -object can-bus,id=canbus0
+ -device kvaser_pci,canbus=canbus0
+ Add "can-host-socketcan" object to connect device to host system CAN bus
+ -object can-host-socketcan,id=canhost0,if=can0,canbus=canbus0
+
+ (2) CAN bus PCM-3680I PCI (dual SJA1000 channel) emulation
+ -object can-bus,id=canbus0
+ -device pcm3680_pci,canbus0=canbus0,canbus1=canbus0
+
+ another example:
+ -object can-bus,id=canbus0
+ -object can-bus,id=canbus1
+ -device pcm3680_pci,canbus0=canbus0,canbus1=canbus1
+
+ (3) CAN bus MIOe-3680 PCI (dual SJA1000 channel) emulation
+ -device mioe3680_pci,canbus0=canbus0
+
+
+The ''kvaser_pci'' board/device model is compatible with and has been tested with
+''kvaser_pci'' driver included in mainline Linux kernel.
+The tested setup was Linux 4.9 kernel on the host and guest side.
+Example for qemu-system-x86_64:
+
+ qemu-system-x86_64 -enable-kvm -kernel /boot/vmlinuz-4.9.0-4-amd64 \
+ -initrd ramdisk.cpio \
+ -virtfs local,path=shareddir,security_model=none,mount_tag=shareddir \
+ -object can-bus,id=canbus0 \
+ -object can-host-socketcan,id=canhost0,if=can0,canbus=canbus0 \
+ -device kvaser_pci,canbus=canbus0 \
+ -nographic -append "console=ttyS0"
+
+Example for qemu-system-arm:
+
+ qemu-system-arm -cpu arm1176 -m 256 -M versatilepb \
+ -kernel kernel-qemu-arm1176-versatilepb \
+ -hda rpi-wheezy-overlay \
+ -append "console=ttyAMA0 root=/dev/sda2 ro init=/sbin/init-overlay" \
+ -nographic \
+ -virtfs local,path=shareddir,security_model=none,mount_tag=shareddir \
+ -object can-bus,id=canbus0 \
+ -object can-host-socketcan,id=canhost0,if=can0,canbus=canbus0 \
+ -device kvaser_pci,canbus=canbus0,host=can0 \
+
+The CAN interface of the host system has to be configured for proper
+bitrate and set up. Configuration is not propagated from emulated
+devices through bus to the physical host device. Example configuration
+for 1 Mbit/s
+
+ ip link set can0 type can bitrate 1000000
+ ip link set can0 up
+
+Virtual (host local only) can interface can be used on the host
+side instead of physical interface
+
+ ip link add dev can0 type vcan
+
+The CAN interface on the host side can be used to analyze CAN
+traffic with "candump" command which is included in "can-utils".
+
+ candump can0
+
+Links to other resources
+========================
+
+ (1) Repository with development branch can-pci at Czech Technical University
+ https://gitlab.fel.cvut.cz/canbus/qemu-canbus
+ (2) GitHub repository with can-pci and our other changes included
+ https://gitlab.fel.cvut.cz/canbus/qemu-canbus
+ (3) RTEMS page describing project
+ https://devel.rtems.org/wiki/Developer/Simulators/QEMU/CANEmulation
+ (4) RTLWS 2015 article about the projevt and its use with CANopen emulation
+ http://rtime.felk.cvut.cz/publications/public/rtlws2015-qemu-can.pdf
+ Slides
+ http://rtime.felk.cvut.cz/publications/public/rtlws2015-qemu-can-slides.pdf
+ (5) Linux SocketCAN utilities
+ https://github.com/linux-can/can-utils/ \ No newline at end of file