1 # SPDX-License-Identifier: GPL-2.0
2 comment "Processor Type"
5 prompt "CPU family support"
6 default M68KCLASSIC if MMU
7 default COLDFIRE if !MMU
9 The Freescale (was Motorola) M68K family of processors implements
10 the full 68000 processor instruction set.
11 The Freescale ColdFire family of processors is a modern derivative
12 of the 68000 processor family. They are mainly targeted at embedded
13 applications, and are all System-On-Chip (SOC) devices, as opposed
14 to stand alone CPUs. They implement a subset of the original 68000
15 processor instruction set.
16 If you anticipate running this kernel on a computer with a classic
17 MC68xxx processor, select M68KCLASSIC.
18 If you anticipate running this kernel on a computer with a ColdFire
19 processor, select COLDFIRE.
22 bool "Classic M68K CPU family support"
23 select HAVE_ARCH_PFN_VALID
26 bool "Coldfire CPU family support"
27 select ARCH_HAVE_CUSTOM_GPIO_H
28 select CPU_HAS_NO_BITFIELDS
29 select CPU_HAS_NO_MULDIV64
32 select HAVE_LEGACY_CLK
41 select CPU_HAS_NO_BITFIELDS
42 select CPU_HAS_NO_MULDIV64
43 select CPU_HAS_NO_UNALIGNED
45 select CPU_NO_EFFICIENT_FFS
48 The Freescale (was Motorola) 68000 CPU is the first generation of
49 the well known M68K family of processors. The CPU core as well as
50 being available as a stand alone CPU was also used in many
51 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
56 select CPU_HAS_NO_BITFIELDS
57 select CPU_HAS_NO_UNALIGNED
58 select CPU_NO_EFFICIENT_FFS
60 The Freescale (was then Motorola) CPU32 is a CPU core that is
61 based on the 68020 processor. For the most part it is used in
62 System-On-Chip parts, and does not contain a paging MMU.
68 select CPU_HAS_ADDRESS_SPACES
70 If you anticipate running this kernel on a computer with a MC68020
71 processor, say Y. Otherwise, say N. Note that the 68020 requires a
72 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
73 Sun 3, which provides its own version.
77 depends on MMU && !MMU_SUN3
79 select CPU_HAS_ADDRESS_SPACES
81 If you anticipate running this kernel on a computer with a MC68030
82 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
83 work, as it does not include an MMU (Memory Management Unit).
87 depends on MMU && !MMU_SUN3
89 select CPU_HAS_ADDRESS_SPACES
91 If you anticipate running this kernel on a computer with a MC68LC040
92 or MC68040 processor, say Y. Otherwise, say N. Note that an
93 MC68EC040 will not work, as it does not include an MMU (Memory
98 depends on MMU && !MMU_SUN3
100 select CPU_HAS_ADDRESS_SPACES
102 If you anticipate running this kernel on a computer with a MC68060
103 processor, say Y. Otherwise, say N.
108 select LEGACY_TIMER_TICK
111 Motorola 68328 processor support.
116 select LEGACY_TIMER_TICK
119 Motorola 68EX328 processor support.
124 select LEGACY_TIMER_TICK
127 Motorola 68VZ328 processor support.
134 prompt "ColdFire SoC type"
137 Select the type of ColdFire System-on-Chip (SoC) that you want
143 select COLDFIRE_SW_A7
144 select COLDFIRE_TIMERS
146 select CPU_NO_EFFICIENT_FFS
148 Motorola ColdFire 5206 processor support.
153 select COLDFIRE_SW_A7
154 select COLDFIRE_TIMERS
156 select CPU_NO_EFFICIENT_FFS
158 Motorola ColdFire 5206e processor support.
163 select COLDFIRE_PIT_TIMER
164 select HAVE_CACHE_SPLIT
166 Freescale Coldfire 5207/5208 processor support.
171 select COLDFIRE_PIT_TIMER
172 select HAVE_CACHE_SPLIT
175 Freescale Coldfire 5230/1/2/4/5 processor support
180 select COLDFIRE_SW_A7
181 select COLDFIRE_TIMERS
183 select CPU_NO_EFFICIENT_FFS
185 Motorola ColdFire 5249 processor support.
190 select COLDFIRE_SW_A7
191 select COLDFIRE_TIMERS
193 select CPU_NO_EFFICIENT_FFS
195 Freescale (Motorola) Coldfire 5251/5253 processor support.
200 select COLDFIRE_PIT_TIMER
202 select HAVE_CACHE_SPLIT
205 Freescale (Motorola) ColdFire 5270/5271 processor support.
210 select COLDFIRE_SW_A7
211 select COLDFIRE_TIMERS
213 select CPU_NO_EFFICIENT_FFS
215 Motorola ColdFire 5272 processor support.
220 select COLDFIRE_PIT_TIMER
222 select HAVE_CACHE_SPLIT
225 Freescale (Motorola) ColdFire 5274/5275 processor support.
230 select COLDFIRE_PIT_TIMER
231 select HAVE_CACHE_SPLIT
234 Motorola ColdFire 5280/5282 processor support.
239 select COLDFIRE_TIMERS
240 select COLDFIRE_SW_A7
243 select CPU_NO_EFFICIENT_FFS
245 Motorola ColdFire 5307 processor support.
250 select COLDFIRE_TIMERS
254 Freescale (Motorola) ColdFire 532x processor support.
259 select COLDFIRE_TIMERS
263 Freescale ColdFire 537x processor support.
268 select COLDFIRE_SW_A7
269 select COLDFIRE_TIMERS
272 select CPU_NO_EFFICIENT_FFS
274 Motorola ColdFire 5407 processor support.
279 select COLDFIRE_SLTIMERS
280 select MMU_COLDFIRE if MMU
284 select CPU_NO_EFFICIENT_FFS
286 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
290 select COLDFIRE_SLTIMERS
291 select MMU_COLDFIRE if MMU
296 select CPU_NO_EFFICIENT_FFS
298 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
302 select COLDFIRE_PIT_TIMER
303 select MMU_COLDFIRE if MMU
306 Freescale Coldfire 54410/54415/54416/54417/54418 processor support.
320 config COLDFIRE_PIT_TIMER
323 config COLDFIRE_TIMERS
325 select LEGACY_TIMER_TICK
327 config COLDFIRE_SLTIMERS
329 select LEGACY_TIMER_TICK
334 comment "Processor Specific Options"
337 bool "Math emulation support"
340 At some point in the future, this will cause floating-point math
341 instructions to be emulated by the kernel on machines that lack a
342 floating-point math coprocessor. Thrill-seekers and chronically
343 sleep-deprived psychotic hacker types can say Y now, everyone else
344 should probably wait a while.
346 config M68KFPU_EMU_EXTRAPREC
347 bool "Math emulation extra precision"
348 depends on M68KFPU_EMU
350 The fpu uses normally a few bit more during calculations for
351 correct rounding, the emulator can (often) do the same but this
352 extra calculation can cost quite some time, so you can disable
353 it here. The emulator will then "only" calculate with a 64 bit
354 mantissa and round slightly incorrect, what is more than enough
357 config M68KFPU_EMU_ONLY
358 bool "Math emulation only kernel"
359 depends on M68KFPU_EMU
361 This option prevents any floating-point instructions from being
362 compiled into the kernel, thereby the kernel doesn't save any
363 floating point context anymore during task switches, so this
364 kernel will only be usable on machines without a floating-point
365 math coprocessor. This makes the kernel a bit faster as no tests
366 needs to be executed whether a floating-point instruction in the
367 kernel should be executed or not.
370 bool "Advanced configuration options"
373 This gives you access to some advanced options for the CPU. The
374 defaults should be fine for most users, but these options may make
375 it possible for you to improve performance somewhat if you know what
378 Note that the answer to this question won't directly affect the
379 kernel: saying N will just cause the configurator to skip all
380 the questions about these options.
382 Most users should say N to this question.
385 bool "Use read-modify-write instructions"
388 This allows to use certain instructions that work with indivisible
389 read-modify-write bus cycles. While this is faster than the
390 workaround of disabling interrupts, it can conflict with DMA
391 ( = direct memory access) on many Amiga systems, and it is also said
392 to destabilize other machines. It is very likely that this will
393 cause serious problems on any Amiga or Atari Medusa if set. The only
394 configuration where it should work are 68030-based Ataris, where it
395 apparently improves performance. But you've been warned! Unless you
396 really know what you are doing, say N. Try Y only if you're quite
399 config SINGLE_MEMORY_CHUNK
400 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
402 default y if SUN3 || MMU_COLDFIRE
404 Ignore all but the first contiguous chunk of physical memory for VM
405 purposes. This will save a few bytes kernel size and may speed up
407 When this option os set to N, you may want to lower "Maximum zone
408 order" to save memory that could be wasted for unused memory map.
411 config FORCE_MAX_ZONEORDER
412 int "Maximum zone order" if ADVANCED
413 depends on !SINGLE_MEMORY_CHUNK
416 The kernel memory allocator divides physically contiguous memory
417 blocks into "zones", where each zone is a power of two number of
418 pages. This option selects the largest power of two that the kernel
419 keeps in the memory allocator. If you need to allocate very large
420 blocks of physically contiguous memory, then you may need to
423 For systems that have holes in their physical address space this
424 value also defines the minimal size of the hole that allows
425 freeing unused memory map.
427 This config option is actually maximum order plus one. For example,
428 a value of 11 means that the largest free memory block is 2^10 pages.
430 config 060_WRITETHROUGH
431 bool "Use write-through caching for 68060 supervisor accesses"
432 depends on ADVANCED && M68060
434 The 68060 generally uses copyback caching of recently accessed data.
435 Copyback caching means that memory writes will be held in an on-chip
436 cache and only written back to memory some time later. Saying Y
437 here will force supervisor (kernel) accesses to use writethrough
438 caching. Writethrough caching means that data is written to memory
439 straight away, so that cache and memory data always agree.
440 Writethrough caching is less efficient, but is needed for some
441 drivers on 68060 based systems where the 68060 bus snooping signal
442 is hardwired on. The 53c710 SCSI driver is known to suffer from
450 config CPU_HAS_NO_BITFIELDS
453 config CPU_HAS_NO_MULDIV64
456 config CPU_HAS_NO_UNALIGNED
459 config CPU_HAS_ADDRESS_SPACES
465 config COLDFIRE_SW_A7
468 config HAVE_CACHE_SPLIT
481 int "Set the core clock frequency"
482 default "25000000" if M5206
483 default "54000000" if M5206e
484 default "166666666" if M520x
485 default "140000000" if M5249
486 default "150000000" if M527x || M523x
487 default "90000000" if M5307
488 default "50000000" if M5407
489 default "266000000" if M54xx
493 Define the CPU clock frequency in use. This is the core clock
494 frequency, it may or may not be the same as the external clock
495 crystal fitted to your board. Some processors have an internal
496 PLL and can have their frequency programmed at run time, others
497 use internal dividers. In general the kernel won't setup a PLL
498 if it is fitted (there are some exceptions). This value will be
499 specific to the exact CPU that you are using.
502 bool "Old mask 5307 (1H55J) silicon"
505 Build support for the older revision ColdFire 5307 silicon.
506 Specifically this is the 1H55J mask revision.
510 prompt "Split Cache Configuration"
516 Use all of the ColdFire CPU cache memory as an instruction cache.
521 Use all of the ColdFire CPU cache memory as a data cache.
526 Split the ColdFire CPU cache, and use half as an instruction cache
527 and half as a data cache.
533 prompt "Data cache mode"
534 default CACHE_WRITETHRU
536 config CACHE_WRITETHRU
539 The ColdFire CPU cache is set into Write-through mode.
541 config CACHE_COPYBACK
544 The ColdFire CPU cache is set into Copy-back mode.