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diff --git a/jslinux-2019-12-21/tinyemu-2019-12-21/readme.txt b/jslinux-2019-12-21/tinyemu-2019-12-21/readme.txt new file mode 100644 index 0000000..ca72f7d --- /dev/null +++ b/jslinux-2019-12-21/tinyemu-2019-12-21/readme.txt @@ -0,0 +1,204 @@ +TinyEMU System Emulator by Fabrice Bellard +========================================== + +1) Features +----------- + +- RISC-V system emulator supporting the RV128IMAFDQC base ISA (user + level ISA version 2.2, priviledged architecture version 1.10) + including: + + - 32/64/128 bit integer registers + - 32/64/128 bit floating point instructions + - Compressed instructions + - dynamic XLEN change + +- x86 system emulator based on KVM + +- VirtIO console, network, block device, input and 9P filesystem + +- Graphical display with SDL + +- JSON configuration file + +- Remote HTTP block device and filesystem + +- small code, easy to modify, no external dependancies + +- Javascript demo version + +2) Installation +--------------- + +- The libraries libcurl, OpenSSL and SDL should be installed. On a Fedora + system you can do it with: + + sudo dnf install openssl-devel libcurl-devel SDL-devel + + It is possible to compile the programs without these libraries by + commenting CONFIG_FS_NET and/or CONFIG_SDL in the Makefile. + +- Edit the Makefile to disable the 128 bit target if you compile on a + 32 bit host (for the 128 bit RISCV target the compiler must support + the __int128 C extension). + +- Use 'make' to compile the binaries. + +- You can optionally install the program to '/usr/local/bin' with: + + make install + +3) Usage +-------- + +3.1 Quick examples +------------------ + +- Use the VM images available from https://bellard.org/jslinux (no + need to download them): + + Terminal: + + ./temu https://bellard.org/jslinux/buildroot-riscv64.cfg + + Graphical (with SDL): + + ./temu https://bellard.org/jslinux/buildroot-x86-xwin.cfg + + ./temu https://bellard.org/jslinux/win2k.cfg + +- Download the example RISC-V Linux image + (diskimage-linux-riscv-yyyy-mm-dd.tar.gz) and use it: + + ./temu root-riscv64.cfg + + ./temu rv128test/rv128test.cfg + +- Access to your local hard disk (/tmp directory) in the guest: + + ./temu root_9p-riscv64.cfg + +then type: +mount -t 9p /dev/root /mnt + +in the guest. The content of the host '/tmp' directory is visible in '/mnt'. + +3.2 Invocation +-------------- + +usage: temu [options] config_file +options are: +-m ram_size set the RAM size in MB +-rw allow write access to the disk image (default=snapshot) +-ctrlc the C-c key stops the emulator instead of being sent to the + emulated software +-append cmdline append cmdline to the kernel command line +-no-accel disable VM acceleration (KVM, x86 machine only) + +Console keys: +Press C-a x to exit the emulator, C-a h to get some help. + +3.3 Network usage +----------------- + +The easiest way is to use the "user" mode network driver. No specific +configuration is necessary. + +TinyEMU also supports a "tap" network driver to redirect the network +traffic from a VirtIO network adapter. + +You can look at the netinit.sh script to create the tap network +interface and to redirect the virtual traffic to Internet thru a +NAT. The exact configuration may depend on the Linux distribution and +local firewall configuration. + +The VM configuration file must include: + +eth0: { driver: "tap", ifname: "tap0" } + +and configure the network in the guest system with: + +ifconfig eth0 192.168.3.2 +route add -net 0.0.0.0 gw 192.168.3.1 eth0 + +3.4 Network filesystem +---------------------- + +TinyEMU supports the VirtIO 9P filesystem to access local or remote +filesystems. For remote filesystems, it does HTTP requests to download +the files. The protocol is compatible with the vfsync utility. In the +"mount" command, "/dev/rootN" must be used as device name where N is +the index of the filesystem. When N=0 it is omitted. + +The build_filelist tool builds the file list from a root directory. A +simple web server is enough to serve the files. + +The '.preload' file gives a list of files to preload when opening a +given file. + +3.5 Network block device +------------------------ + +TinyEMU supports an HTTP block device. The disk image is split into +small files. Use the 'splitimg' utility to generate images. The URL of +the JSON blk.txt file must be provided as disk image filename. + +4) Technical notes +------------------ + +4.1) 128 bit support + +The RISC-V specification does not define all the instruction encodings +for the 128 bit integer and floating point operations. The missing +ones were interpolated from the 32 and 64 ones. + +Unfortunately there is no RISC-V 128 bit toolchain nor OS now +(volunteers for the Linux port ?), so rv128test.bin may be the first +128 bit code for RISC-V ! + +4.2) Floating point emulation + +The floating point emulation is bit exact and supports all the +specified instructions for 32, 64 and 128 bit floating point +numbers. It uses the new SoftFP library. + +4.3) HTIF console + +The standard HTIF console uses registers at variable addresses which +are deduced by loading specific ELF symbols. TinyEMU does not rely on +an ELF loader, so it is much simpler to use registers at fixed +addresses (0x40008000). A small modification was made in the +"riscv-pk" boot loader to support it. The HTIF console is only used to +display boot messages and to power off the virtual system. The OS +should use the VirtIO console. + +4.4) Javascript version + +The Javascript version (JSLinux) can be compiled with Makefile.js and +emscripten. A complete precompiled and preconfigured demo is available +in the jslinux-yyyy-mm-dd.tar.gz archive (read the readme.txt file +inside the archive). + +4.5) x86 emulator + +A small x86 emulator is included. It is not really an emulator because +it uses the Linux KVM API to run the x86 code at near native +performance. The x86 emulator uses the same set of VirtIO devices as +the RISCV emulator and is able to run many operating systems. + +The x86 emulator accepts a Linux kernel image (bzImage). No BIOS image +is necessary. + +The x86 emulator comes from my JS/Linux project (2011) which was one +of the first emulator running Linux fully implemented in +Javascript. It is provided to allow easy access to the x86 images +hosted at https://bellard.org/jslinux . + + +5) License / Credits +-------------------- + +TinyEMU is released under the MIT license. If there is no explicit +license in a file, the license from MIT-LICENSE.txt applies. + +The SLIRP library has its own license (two clause BSD license). |