xref: /openbmc/linux/arch/nios2/Kconfig (revision 81de3bf3) 
1# SPDX-License-Identifier: GPL-2.0
2config NIOS2
3	def_bool y
4	select ARCH_32BIT_OFF_T
5	select ARCH_HAS_SYNC_DMA_FOR_CPU
6	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
7	select ARCH_HAS_UNCACHED_SEGMENT
8	select ARCH_NO_SWAP
9	select TIMER_OF
10	select GENERIC_ATOMIC64
11	select GENERIC_CLOCKEVENTS
12	select GENERIC_CPU_DEVICES
13	select GENERIC_IRQ_PROBE
14	select GENERIC_IRQ_SHOW
15	select GENERIC_STRNCPY_FROM_USER
16	select GENERIC_STRNLEN_USER
17	select HAVE_ARCH_TRACEHOOK
18	select HAVE_ARCH_KGDB
19	select IRQ_DOMAIN
20	select MODULES_USE_ELF_RELA
21	select OF
22	select OF_EARLY_FLATTREE
23	select SOC_BUS
24	select SPARSE_IRQ
25	select USB_ARCH_HAS_HCD if USB_SUPPORT
26	select CPU_NO_EFFICIENT_FFS
27	select MMU_GATHER_NO_RANGE if MMU
28
29config GENERIC_CSUM
30	def_bool y
31
32config GENERIC_HWEIGHT
33	def_bool y
34
35config GENERIC_CALIBRATE_DELAY
36	def_bool y
37
38config NO_IOPORT_MAP
39	def_bool y
40
41config FPU
42	def_bool n
43
44config TRACE_IRQFLAGS_SUPPORT
45	def_bool n
46
47menu "Kernel features"
48
49source "kernel/Kconfig.hz"
50
51config FORCE_MAX_ZONEORDER
52	int "Maximum zone order"
53	range 9 20
54	default "11"
55	help
56	  The kernel memory allocator divides physically contiguous memory
57	  blocks into "zones", where each zone is a power of two number of
58	  pages.  This option selects the largest power of two that the kernel
59	  keeps in the memory allocator.  If you need to allocate very large
60	  blocks of physically contiguous memory, then you may need to
61	  increase this value.
62
63	  This config option is actually maximum order plus one. For example,
64	  a value of 11 means that the largest free memory block is 2^10 pages.
65
66endmenu
67
68source "arch/nios2/platform/Kconfig.platform"
69
70menu "Processor type and features"
71
72config MMU
73	def_bool y
74
75config NR_CPUS
76	int
77	default "1"
78
79config NIOS2_ALIGNMENT_TRAP
80	bool "Catch alignment trap"
81	default y
82	help
83	  Nios II CPUs cannot fetch/store data which is not bus aligned,
84	  i.e., a 2 or 4 byte fetch must start at an address divisible by
85	  2 or 4. Any non-aligned load/store instructions will be trapped and
86	  emulated in software if you say Y here, which has a performance
87	  impact.
88
89comment "Boot options"
90
91config CMDLINE_BOOL
92	bool "Default bootloader kernel arguments"
93	default y
94
95config CMDLINE
96	string "Default kernel command string"
97	default ""
98	depends on CMDLINE_BOOL
99	help
100	  On some platforms, there is currently no way for the boot loader to
101	  pass arguments to the kernel. For these platforms, you can supply
102	  some command-line options at build time by entering them here.  In
103	  other cases you can specify kernel args so that you don't have
104	  to set them up in board prom initialization routines.
105
106config CMDLINE_FORCE
107	bool "Force default kernel command string"
108	depends on CMDLINE_BOOL
109	help
110	  Set this to have arguments from the default kernel command string
111	  override those passed by the boot loader.
112
113config NIOS2_CMDLINE_IGNORE_DTB
114	bool "Ignore kernel command string from DTB"
115	depends on CMDLINE_BOOL
116	depends on !CMDLINE_FORCE
117	default y
118	help
119	  Set this to ignore the bootargs property from the devicetree's
120	  chosen node and fall back to CMDLINE if nothing is passed.
121
122config NIOS2_PASS_CMDLINE
123	bool "Passed kernel command line from u-boot"
124	help
125	  Use bootargs env variable from u-boot for kernel command line.
126	  will override "Default kernel command string".
127	  Say N if you are unsure.
128
129config NIOS2_BOOT_LINK_OFFSET
130	hex "Link address offset for booting"
131	default "0x00500000"
132	help
133	  This option allows you to set the link address offset of the zImage.
134	  This can be useful if you are on a board which has a small amount of
135	  memory.
136
137endmenu
138
139menu "Advanced setup"
140
141config ADVANCED_OPTIONS
142	bool "Prompt for advanced kernel configuration options"
143
144comment "Default settings for advanced configuration options are used"
145	depends on !ADVANCED_OPTIONS
146
147config NIOS2_KERNEL_MMU_REGION_BASE_BOOL
148	bool "Set custom kernel MMU region base address"
149	depends on ADVANCED_OPTIONS
150	help
151	  This option allows you to set the virtual address of the kernel MMU region.
152
153	  Say N here unless you know what you are doing.
154
155config NIOS2_KERNEL_MMU_REGION_BASE
156	hex "Virtual base address of the kernel MMU region " if NIOS2_KERNEL_MMU_REGION_BASE_BOOL
157	default "0x80000000"
158	help
159	  This option allows you to set the virtual base address of the kernel MMU region.
160
161config NIOS2_KERNEL_REGION_BASE_BOOL
162	bool "Set custom kernel region base address"
163	depends on ADVANCED_OPTIONS
164	help
165	  This option allows you to set the virtual address of the kernel region.
166
167	  Say N here unless you know what you are doing.
168
169config NIOS2_KERNEL_REGION_BASE
170	hex "Virtual base address of the kernel region " if NIOS2_KERNEL_REGION_BASE_BOOL
171	default "0xc0000000"
172
173config NIOS2_IO_REGION_BASE_BOOL
174	bool "Set custom I/O region base address"
175	depends on ADVANCED_OPTIONS
176	help
177	  This option allows you to set the virtual address of the I/O region.
178
179	  Say N here unless you know what you are doing.
180
181config NIOS2_IO_REGION_BASE
182	hex "Virtual base address of the I/O region" if NIOS2_IO_REGION_BASE_BOOL
183	default "0xe0000000"
184
185endmenu
186