xref: /freebsd/sys/riscv/conf/NOTES (revision 3e8eb5c7f4909209c042403ddee340b2ee7003a5)
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# pseudo devices
27device		clk
28device		hwreset
29device		phy
30device		regulator
31device		syscon
32device		syscon_power
33device		riscv_syscon
34
35# Backlight subsystem
36device		backlight
37
38# VirtIO support
39device		virtio			# Generic VirtIO bus (required)
40device		virtio_pci		# VirtIO PCI device
41device		vtnet			# VirtIO Ethernet device
42device		virtio_blk		# VirtIO Block device
43device		virtio_mmio		# VirtIO MMIO bus
44device		virtio_random		# VirtIO Entropy device
45
46# NVM Express (NVMe) support
47device		nvme		# base NVMe driver
48options 	NVME_USE_NVD=0	# prefer the cam(4) based nda(4) driver
49device		nvd		# expose NVMe namespaces as disks, depends on nvme
50
51# NOTE: dtrace introduces CDDL-licensed components into the kernel
52device		dtrace			# dtrace core
53device		dtraceall		# include all dtrace modules
54
55# Serial (COM) ports
56device		uart_lowrisc	# lowRISC UART driver
57device		uart_ns8250	# ns8250-type UART driver
58
59# RTC
60device		goldfish_rtc	# QEMU RTC
61
62# Ethernet drivers
63device		xae		# Xilinx AXI Ethernet MAC
64
65# DMA support
66device		xdma		# DMA interface
67device		axidma		# Xilinx AXI DMA Controller
68
69# SPI
70device		xilinx_spi	# Xilinx AXI Quad-SPI Controller
71
72# SiFive device drivers
73device		fe310aon
74device		fu740_pci_dw
75device		sifive_gpio
76device		sifive_spi
77files		"../sifive/files.sifive"
78
79# Flattened Device Tree
80options 	FDT
81makeoptions	MODULES_EXTRA+="dtb/sifive"
82
83# FreeBSD/riscv didn't exist for these releases
84nooptions 	COMPAT_FREEBSD4
85nooptions 	COMPAT_FREEBSD5
86nooptions 	COMPAT_FREEBSD6
87nooptions 	COMPAT_FREEBSD7
88nooptions 	COMPAT_FREEBSD9
89nooptions 	COMPAT_FREEBSD10
90nooptions 	COMPAT_FREEBSD11
91
92# riscv doesn't support inb/outb, so disable chipset probing which needs it
93nooptions 	PPC_PROBE_CHIPSET
94
95# Makes assumptions about bus tags that aren't true on riscv
96nodevice	snd_cmi
97
98# Don't yet have hwpmc(4)
99nodevice	hwpmc
100nooptions 	HWPMC_HOOKS
101
102# riscv doesn't yet have atomic_testandset_int and atomic_testandclear_int.
103nodevice	ccr
104nodevice	cxgbe
105nodevice	cxgbev
106