xref: /freebsd/sys/riscv/conf/NOTES (revision 19261079)
1#
2# NOTES -- Lines that can be cut/pasted into kernel and hints configs.
3#
4# This file contains machine dependent kernel configuration notes.  For
5# machine independent notes, look in /sys/conf/NOTES.
6#
7# $FreeBSD$
8#
9
10cpu		RISCV
11
12makeoptions	DEBUG=-g		# Build kernel with gdb(1) debug symbols
13makeoptions	WITH_CTF=1		# Run ctfconvert(1) for DTrace support
14
15options 	PRINTF_BUFR_SIZE=128	# Prevent printf output being interspersed.
16options 	KDTRACE_FRAME		# Ensure frames are compiled in
17options 	KDTRACE_HOOKS		# Kernel DTrace hooks
18options 	DDB_CTF			# Kernel ELF linker loads CTF data
19options 	FPE			# Floating-point extension support
20options 	RACCT_DEFAULT_TO_DISABLED # Set kern.racct.enable=0 by default
21options 	INTRNG			# Include INTRNG framework
22
23# RISC-V SBI console
24device		rcons
25
26# EXT_RESOURCES pseudo devices
27options 	EXT_RESOURCES
28device		clk
29device		hwreset
30device		phy
31device		regulator
32device		syscon
33device		syscon_power
34device		riscv_syscon
35
36# Backlight subsystem
37device		backlight
38
39# VirtIO support
40device		virtio			# Generic VirtIO bus (required)
41device		virtio_pci		# VirtIO PCI device
42device		vtnet			# VirtIO Ethernet device
43device		virtio_blk		# VirtIO Block device
44device		virtio_mmio		# VirtIO MMIO bus
45device		virtio_random		# VirtIO Entropy device
46
47# NVM Express (NVMe) support
48device		nvme		# base NVMe driver
49options 	NVME_USE_NVD=0	# prefer the cam(4) based nda(4) driver
50device		nvd		# expose NVMe namespaces as disks, depends on nvme
51
52# NOTE: dtrace introduces CDDL-licensed components into the kernel
53device		dtrace			# dtrace core
54device		dtraceall		# include all dtrace modules
55
56# Serial (COM) ports
57device		uart_lowrisc	# lowRISC UART driver
58device		uart_ns8250	# ns8250-type UART driver
59
60# RTC
61device		goldfish_rtc	# QEMU RTC
62
63# Ethernet drivers
64device		xae		# Xilinx AXI Ethernet MAC
65
66# DMA support
67device		xdma		# DMA interface
68device		axidma		# Xilinx AXI DMA Controller
69
70# SPI
71device		xilinx_spi	# Xilinx AXI Quad-SPI Controller
72
73# SiFive device drivers
74device		fe310aon
75device		fu740_pci_dw
76device		sifive_gpio
77device		sifive_spi
78files		"../sifive/files.sifive"
79
80# Flattened Device Tree
81options 	FDT
82makeoptions	MODULES_EXTRA+="dtb/sifive"
83
84# FreeBSD/riscv didn't exist for these releases
85nooptions 	COMPAT_FREEBSD4
86nooptions 	COMPAT_FREEBSD5
87nooptions 	COMPAT_FREEBSD6
88nooptions 	COMPAT_FREEBSD7
89nooptions 	COMPAT_FREEBSD9
90nooptions 	COMPAT_FREEBSD10
91nooptions 	COMPAT_FREEBSD11
92
93# No support for remote GDB
94nooptions 	GDB
95
96# riscv doesn't support inb/outb, so disable chipset probing which needs it
97nooptions 	PPC_PROBE_CHIPSET
98
99# Makes assumptions about bus tags that aren't true on riscv
100nodevice	snd_cmi
101
102# Don't yet have hwpmc(4)
103nodevice	hwpmc
104nooptions 	HWPMC_HOOKS
105