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
30 select CPU_HAS_NO_MULDIV64
33 select HAVE_LEGACY_CLK
42 select CPU_HAS_NO_BITFIELDS
44 select CPU_HAS_NO_MULDIV64
45 select CPU_HAS_NO_UNALIGNED
47 select CPU_NO_EFFICIENT_FFS
50 The Freescale (was Motorola) 68000 CPU is the first generation of
51 the well known M68K family of processors. The CPU core as well as
52 being available as a stand alone CPU was also used in many
53 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
58 select CPU_HAS_NO_BITFIELDS
60 select CPU_HAS_NO_UNALIGNED
61 select CPU_NO_EFFICIENT_FFS
63 The Freescale (was then Motorola) CPU32 is a CPU core that is
64 based on the 68020 processor. For the most part it is used in
65 System-On-Chip parts, and does not contain a paging MMU.
71 select CPU_HAS_ADDRESS_SPACES
73 If you anticipate running this kernel on a computer with a MC68020
74 processor, say Y. Otherwise, say N. Note that the 68020 requires a
75 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
76 Sun 3, which provides its own version.
80 depends on MMU && !MMU_SUN3
82 select CPU_HAS_ADDRESS_SPACES
84 If you anticipate running this kernel on a computer with a MC68030
85 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
86 work, as it does not include an MMU (Memory Management Unit).
90 depends on MMU && !MMU_SUN3
92 select CPU_HAS_ADDRESS_SPACES
94 If you anticipate running this kernel on a computer with a MC68LC040
95 or MC68040 processor, say Y. Otherwise, say N. Note that an
96 MC68EC040 will not work, as it does not include an MMU (Memory
101 depends on MMU && !MMU_SUN3
103 select CPU_HAS_ADDRESS_SPACES
105 If you anticipate running this kernel on a computer with a MC68060
106 processor, say Y. Otherwise, say N.
111 select LEGACY_TIMER_TICK
114 Motorola 68328 processor support.
119 select LEGACY_TIMER_TICK
122 Motorola 68EX328 processor support.
127 select LEGACY_TIMER_TICK
130 Motorola 68VZ328 processor support.
137 prompt "ColdFire SoC type"
140 Select the type of ColdFire System-on-Chip (SoC) that you want
146 select COLDFIRE_SW_A7
147 select COLDFIRE_TIMERS
149 select CPU_NO_EFFICIENT_FFS
151 Motorola ColdFire 5206 processor support.
156 select COLDFIRE_SW_A7
157 select COLDFIRE_TIMERS
159 select CPU_NO_EFFICIENT_FFS
161 Motorola ColdFire 5206e processor support.
166 select COLDFIRE_PIT_TIMER
167 select HAVE_CACHE_SPLIT
169 Freescale Coldfire 5207/5208 processor support.
174 select COLDFIRE_PIT_TIMER
175 select HAVE_CACHE_SPLIT
178 Freescale Coldfire 5230/1/2/4/5 processor support
183 select COLDFIRE_SW_A7
184 select COLDFIRE_TIMERS
186 select CPU_NO_EFFICIENT_FFS
188 Motorola ColdFire 5249 processor support.
193 select COLDFIRE_SW_A7
194 select COLDFIRE_TIMERS
196 select CPU_NO_EFFICIENT_FFS
198 Freescale (Motorola) Coldfire 5251/5253 processor support.
203 select COLDFIRE_PIT_TIMER
205 select HAVE_CACHE_SPLIT
208 Freescale (Motorola) ColdFire 5270/5271 processor support.
213 select COLDFIRE_SW_A7
214 select COLDFIRE_TIMERS
216 select CPU_NO_EFFICIENT_FFS
218 Motorola ColdFire 5272 processor support.
223 select COLDFIRE_PIT_TIMER
225 select HAVE_CACHE_SPLIT
228 Freescale (Motorola) ColdFire 5274/5275 processor support.
233 select COLDFIRE_PIT_TIMER
234 select HAVE_CACHE_SPLIT
237 Motorola ColdFire 5280/5282 processor support.
242 select COLDFIRE_TIMERS
243 select COLDFIRE_SW_A7
246 select CPU_NO_EFFICIENT_FFS
248 Motorola ColdFire 5307 processor support.
253 select COLDFIRE_TIMERS
257 Freescale (Motorola) ColdFire 532x processor support.
262 select COLDFIRE_TIMERS
266 Freescale ColdFire 537x processor support.
271 select COLDFIRE_SW_A7
272 select COLDFIRE_TIMERS
275 select CPU_NO_EFFICIENT_FFS
277 Motorola ColdFire 5407 processor support.
282 select COLDFIRE_SLTIMERS
283 select MMU_COLDFIRE if MMU
287 select CPU_NO_EFFICIENT_FFS
289 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
293 select COLDFIRE_SLTIMERS
294 select MMU_COLDFIRE if MMU
299 select CPU_NO_EFFICIENT_FFS
301 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
305 select COLDFIRE_PIT_TIMER
306 select MMU_COLDFIRE if MMU
309 Freescale Coldfire 54410/54415/54416/54417/54418 processor support.
323 config COLDFIRE_PIT_TIMER
326 config COLDFIRE_TIMERS
328 select LEGACY_TIMER_TICK
330 config COLDFIRE_SLTIMERS
332 select LEGACY_TIMER_TICK
337 comment "Processor Specific Options"
340 bool "Math emulation support"
341 depends on M68KCLASSIC && FPU
343 At some point in the future, this will cause floating-point math
344 instructions to be emulated by the kernel on machines that lack a
345 floating-point math coprocessor. Thrill-seekers and chronically
346 sleep-deprived psychotic hacker types can say Y now, everyone else
347 should probably wait a while.
349 config M68KFPU_EMU_EXTRAPREC
350 bool "Math emulation extra precision"
351 depends on M68KFPU_EMU
353 The fpu uses normally a few bit more during calculations for
354 correct rounding, the emulator can (often) do the same but this
355 extra calculation can cost quite some time, so you can disable
356 it here. The emulator will then "only" calculate with a 64 bit
357 mantissa and round slightly incorrect, what is more than enough
360 config M68KFPU_EMU_ONLY
361 bool "Math emulation only kernel"
362 depends on M68KFPU_EMU
364 This option prevents any floating-point instructions from being
365 compiled into the kernel, thereby the kernel doesn't save any
366 floating point context anymore during task switches, so this
367 kernel will only be usable on machines without a floating-point
368 math coprocessor. This makes the kernel a bit faster as no tests
369 needs to be executed whether a floating-point instruction in the
370 kernel should be executed or not.
373 bool "Advanced configuration options"
376 This gives you access to some advanced options for the CPU. The
377 defaults should be fine for most users, but these options may make
378 it possible for you to improve performance somewhat if you know what
381 Note that the answer to this question won't directly affect the
382 kernel: saying N will just cause the configurator to skip all
383 the questions about these options.
385 Most users should say N to this question.
388 bool "Use read-modify-write instructions"
389 depends on ADVANCED && !CPU_HAS_NO_CAS
391 This allows to use certain instructions that work with indivisible
392 read-modify-write bus cycles. While this is faster than the
393 workaround of disabling interrupts, it can conflict with DMA
394 ( = direct memory access) on many Amiga systems, and it is also said
395 to destabilize other machines. It is very likely that this will
396 cause serious problems on any Amiga or Atari Medusa if set. The only
397 configuration where it should work are 68030-based Ataris, where it
398 apparently improves performance. But you've been warned! Unless you
399 really know what you are doing, say N. Try Y only if you're quite
402 config SINGLE_MEMORY_CHUNK
403 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
405 default y if SUN3 || MMU_COLDFIRE
407 Ignore all but the first contiguous chunk of physical memory for VM
408 purposes. This will save a few bytes kernel size and may speed up
410 When this option os set to N, you may want to lower "Maximum zone
411 order" to save memory that could be wasted for unused memory map.
414 config FORCE_MAX_ZONEORDER
415 int "Maximum zone order" if ADVANCED
416 depends on !SINGLE_MEMORY_CHUNK
419 The kernel memory allocator divides physically contiguous memory
420 blocks into "zones", where each zone is a power of two number of
421 pages. This option selects the largest power of two that the kernel
422 keeps in the memory allocator. If you need to allocate very large
423 blocks of physically contiguous memory, then you may need to
426 For systems that have holes in their physical address space this
427 value also defines the minimal size of the hole that allows
428 freeing unused memory map.
430 This config option is actually maximum order plus one. For example,
431 a value of 11 means that the largest free memory block is 2^10 pages.
433 config 060_WRITETHROUGH
434 bool "Use write-through caching for 68060 supervisor accesses"
435 depends on ADVANCED && M68060
437 The 68060 generally uses copyback caching of recently accessed data.
438 Copyback caching means that memory writes will be held in an on-chip
439 cache and only written back to memory some time later. Saying Y
440 here will force supervisor (kernel) accesses to use writethrough
441 caching. Writethrough caching means that data is written to memory
442 straight away, so that cache and memory data always agree.
443 Writethrough caching is less efficient, but is needed for some
444 drivers on 68060 based systems where the 68060 bus snooping signal
445 is hardwired on. The 53c710 SCSI driver is known to suffer from
453 config CPU_HAS_NO_BITFIELDS
456 config CPU_HAS_NO_CAS
459 config CPU_HAS_NO_MULDIV64
462 config CPU_HAS_NO_UNALIGNED
465 config CPU_HAS_ADDRESS_SPACES
471 config COLDFIRE_SW_A7
474 config HAVE_CACHE_SPLIT
487 int "Set the core clock frequency"
488 default "25000000" if M5206
489 default "54000000" if M5206e
490 default "166666666" if M520x
491 default "140000000" if M5249
492 default "150000000" if M527x || M523x
493 default "90000000" if M5307
494 default "50000000" if M5407
495 default "266000000" if M54xx
499 Define the CPU clock frequency in use. This is the core clock
500 frequency, it may or may not be the same as the external clock
501 crystal fitted to your board. Some processors have an internal
502 PLL and can have their frequency programmed at run time, others
503 use internal dividers. In general the kernel won't setup a PLL
504 if it is fitted (there are some exceptions). This value will be
505 specific to the exact CPU that you are using.
508 bool "Old mask 5307 (1H55J) silicon"
511 Build support for the older revision ColdFire 5307 silicon.
512 Specifically this is the 1H55J mask revision.
516 prompt "Split Cache Configuration"
522 Use all of the ColdFire CPU cache memory as an instruction cache.
527 Use all of the ColdFire CPU cache memory as a data cache.
532 Split the ColdFire CPU cache, and use half as an instruction cache
533 and half as a data cache.
539 prompt "Data cache mode"
540 default CACHE_WRITETHRU
542 config CACHE_WRITETHRU
545 The ColdFire CPU cache is set into Write-through mode.
547 config CACHE_COPYBACK
550 The ColdFire CPU cache is set into Copy-back mode.