febe2bd226
This allows us to boot FreeBSD RISCV on QEMU using the -kernel command line options. When using that option, QEMU maps the kernel ELF file to the addresses specified in the LMAs in the program headers. Since version 4.2 QEMU ships with OpenSBI fw_jump by default so this allows booting FreeBSD using the following command line: qemu-system-riscv64 -bios default -kernel /.../boot/kernel/kernel -nographic -M virt Without this change the -kernel option cannot be used since the LMAs start at address zero and QEMU already maps a ROM to these low physical addresses. For targets that require a different kernel LMA the make variable KERNEL_LMA can be overwritten in the config file. For example, adding `makeoptions KERNEL_LMA=0xc0200000` will create an ELF file that will be loaded at 0xc0200000. Before: There are 4 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align LOAD 0x001000 0xffffffc000000000 0x0000000000000000 0x75e598 0x8be318 RWE 0x1000 DYNAMIC 0x71fb20 0xffffffc00071eb20 0x000000000071eb20 0x000100 0x000100 RW 0x8 GNU_STACK 0x000000 0x0000000000000000 0x0000000000000000 0x000000 0x000000 RW 0x0 NOTE 0x693400 0xffffffc000692400 0x0000000000692400 0x000024 0x000024 R 0x4 After: There are 4 program headers, starting at offset 64 Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align LOAD 0x001000 0xffffffc000000000 0x0000000080200000 0x734198 0x893e18 RWE 0x1000 DYNAMIC 0x6f7810 0xffffffc0006f6810 0x00000000808f6810 0x000100 0x000100 RW 0x8 GNU_STACK 0x000000 0x0000000000000000 0x0000000000000000 0x000000 0x000000 RW 0x0 NOTE 0x66ca70 0xffffffc00066ba70 0x000000008086ba70 0x000024 0x000024 R 0x4 Reviewed By: br, mhorne (earlier version) Differential Revision: https://reviews.freebsd.org/D23436
FreeBSD Source:
This is the top level of the FreeBSD source directory. This file
was last revised on:
FreeBSD
FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
For copyright information, please see the file COPYRIGHT in this directory. Additional copyright information also exists for some sources in this tree - please see the specific source directories for more information.
The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7), config(8), https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html, and https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html for more information, including setting make(1) variables.
Source Roadmap:
bin System/user commands.
cddl Various commands and libraries under the Common Development
and Distribution License.
contrib Packages contributed by 3rd parties.
crypto Cryptography stuff (see crypto/README).
etc Template files for /etc.
gnu Various commands and libraries under the GNU Public License.
Please see gnu/COPYING* for more information.
include System include files.
kerberos5 Kerberos5 (Heimdal) package.
lib System libraries.
libexec System daemons.
release Release building Makefile & associated tools.
rescue Build system for statically linked /rescue utilities.
sbin System commands.
secure Cryptographic libraries and commands.
share Shared resources.
stand Boot loader sources.
sys Kernel sources.
sys/<arch>/conf Kernel configuration files. GENERIC is the configuration
used in release builds. NOTES contains documentation of
all possible entries.
tests Regression tests which can be run by Kyua. See tests/README
for additional information.
tools Utilities for regression testing and miscellaneous tasks.
usr.bin User commands.
usr.sbin System administration commands.
For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see:
https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/current-stable.html