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"
25 bool "Coldfire CPU family support"
26 select ARCH_HAVE_CUSTOM_GPIO_H
27 select CPU_HAS_NO_BITFIELDS
28 select CPU_HAS_NO_MULDIV64
40 select CPU_HAS_NO_BITFIELDS
41 select CPU_HAS_NO_MULDIV64
42 select CPU_HAS_NO_UNALIGNED
44 select CPU_NO_EFFICIENT_FFS
47 The Freescale (was Motorola) 68000 CPU is the first generation of
48 the well known M68K family of processors. The CPU core as well as
49 being available as a stand alone CPU was also used in many
50 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
55 select CPU_HAS_NO_BITFIELDS
56 select CPU_HAS_NO_UNALIGNED
57 select CPU_NO_EFFICIENT_FFS
59 The Freescale (was then Motorola) CPU32 is a CPU core that is
60 based on the 68020 processor. For the most part it is used in
61 System-On-Chip parts, and does not contain a paging MMU.
67 select CPU_HAS_ADDRESS_SPACES
69 If you anticipate running this kernel on a computer with a MC68020
70 processor, say Y. Otherwise, say N. Note that the 68020 requires a
71 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
72 Sun 3, which provides its own version.
76 depends on MMU && !MMU_SUN3
78 select CPU_HAS_ADDRESS_SPACES
80 If you anticipate running this kernel on a computer with a MC68030
81 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
82 work, as it does not include an MMU (Memory Management Unit).
86 depends on MMU && !MMU_SUN3
88 select CPU_HAS_ADDRESS_SPACES
90 If you anticipate running this kernel on a computer with a MC68LC040
91 or MC68040 processor, say Y. Otherwise, say N. Note that an
92 MC68EC040 will not work, as it does not include an MMU (Memory
97 depends on MMU && !MMU_SUN3
99 select CPU_HAS_ADDRESS_SPACES
101 If you anticipate running this kernel on a computer with a MC68060
102 processor, say Y. Otherwise, say N.
109 Motorola 68328 processor support.
116 Motorola 68EX328 processor support.
123 Motorola 68VZ328 processor support.
130 prompt "ColdFire SoC type"
133 Select the type of ColdFire System-on-Chip (SoC) that you want
139 select COLDFIRE_SW_A7
141 select CPU_NO_EFFICIENT_FFS
143 Motorola ColdFire 5206 processor support.
148 select COLDFIRE_SW_A7
150 select CPU_NO_EFFICIENT_FFS
152 Motorola ColdFire 5206e processor support.
157 select GENERIC_CLOCKEVENTS
158 select HAVE_CACHE_SPLIT
160 Freescale Coldfire 5207/5208 processor support.
165 select GENERIC_CLOCKEVENTS
166 select HAVE_CACHE_SPLIT
169 Freescale Coldfire 5230/1/2/4/5 processor support
174 select COLDFIRE_SW_A7
176 select CPU_NO_EFFICIENT_FFS
178 Motorola ColdFire 5249 processor support.
183 select COLDFIRE_SW_A7
185 select CPU_NO_EFFICIENT_FFS
187 Freescale (Motorola) Coldfire 5251/5253 processor support.
193 select HAVE_CACHE_SPLIT
195 select GENERIC_CLOCKEVENTS
197 Freescale (Motorola) ColdFire 5270/5271 processor support.
202 select COLDFIRE_SW_A7
204 select CPU_NO_EFFICIENT_FFS
206 Motorola ColdFire 5272 processor support.
212 select HAVE_CACHE_SPLIT
214 select GENERIC_CLOCKEVENTS
216 Freescale (Motorola) ColdFire 5274/5275 processor support.
221 select GENERIC_CLOCKEVENTS
222 select HAVE_CACHE_SPLIT
225 Motorola ColdFire 5280/5282 processor support.
230 select COLDFIRE_SW_A7
233 select CPU_NO_EFFICIENT_FFS
235 Motorola ColdFire 5307 processor support.
243 Freescale (Motorola) ColdFire 532x processor support.
251 Freescale ColdFire 537x processor support.
256 select COLDFIRE_SW_A7
259 select CPU_NO_EFFICIENT_FFS
261 Motorola ColdFire 5407 processor support.
266 select MMU_COLDFIRE if MMU
270 select CPU_NO_EFFICIENT_FFS
272 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
276 select MMU_COLDFIRE if MMU
281 select CPU_NO_EFFICIENT_FFS
283 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
287 select MMU_COLDFIRE if MMU
288 select GENERIC_CLOCKEVENTS
291 Freescale Coldfire 54410/54415/54416/54417/54418 processor support.
308 comment "Processor Specific Options"
311 bool "Math emulation support"
314 At some point in the future, this will cause floating-point math
315 instructions to be emulated by the kernel on machines that lack a
316 floating-point math coprocessor. Thrill-seekers and chronically
317 sleep-deprived psychotic hacker types can say Y now, everyone else
318 should probably wait a while.
320 config M68KFPU_EMU_EXTRAPREC
321 bool "Math emulation extra precision"
322 depends on M68KFPU_EMU
324 The fpu uses normally a few bit more during calculations for
325 correct rounding, the emulator can (often) do the same but this
326 extra calculation can cost quite some time, so you can disable
327 it here. The emulator will then "only" calculate with a 64 bit
328 mantissa and round slightly incorrect, what is more than enough
331 config M68KFPU_EMU_ONLY
332 bool "Math emulation only kernel"
333 depends on M68KFPU_EMU
335 This option prevents any floating-point instructions from being
336 compiled into the kernel, thereby the kernel doesn't save any
337 floating point context anymore during task switches, so this
338 kernel will only be usable on machines without a floating-point
339 math coprocessor. This makes the kernel a bit faster as no tests
340 needs to be executed whether a floating-point instruction in the
341 kernel should be executed or not.
344 bool "Advanced configuration options"
347 This gives you access to some advanced options for the CPU. The
348 defaults should be fine for most users, but these options may make
349 it possible for you to improve performance somewhat if you know what
352 Note that the answer to this question won't directly affect the
353 kernel: saying N will just cause the configurator to skip all
354 the questions about these options.
356 Most users should say N to this question.
359 bool "Use read-modify-write instructions"
362 This allows to use certain instructions that work with indivisible
363 read-modify-write bus cycles. While this is faster than the
364 workaround of disabling interrupts, it can conflict with DMA
365 ( = direct memory access) on many Amiga systems, and it is also said
366 to destabilize other machines. It is very likely that this will
367 cause serious problems on any Amiga or Atari Medusa if set. The only
368 configuration where it should work are 68030-based Ataris, where it
369 apparently improves performance. But you've been warned! Unless you
370 really know what you are doing, say N. Try Y only if you're quite
373 config SINGLE_MEMORY_CHUNK
374 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
377 select NEED_MULTIPLE_NODES
379 Ignore all but the first contiguous chunk of physical memory for VM
380 purposes. This will save a few bytes kernel size and may speed up
381 some operations. Say N if not sure.
383 config ARCH_DISCONTIGMEM_ENABLE
384 def_bool MMU && !SINGLE_MEMORY_CHUNK
386 config 060_WRITETHROUGH
387 bool "Use write-through caching for 68060 supervisor accesses"
388 depends on ADVANCED && M68060
390 The 68060 generally uses copyback caching of recently accessed data.
391 Copyback caching means that memory writes will be held in an on-chip
392 cache and only written back to memory some time later. Saying Y
393 here will force supervisor (kernel) accesses to use writethrough
394 caching. Writethrough caching means that data is written to memory
395 straight away, so that cache and memory data always agree.
396 Writethrough caching is less efficient, but is needed for some
397 drivers on 68060 based systems where the 68060 bus snooping signal
398 is hardwired on. The 53c710 SCSI driver is known to suffer from
409 depends on !SINGLE_MEMORY_CHUNK
411 config CPU_HAS_NO_BITFIELDS
414 config CPU_HAS_NO_MULDIV64
417 config CPU_HAS_NO_UNALIGNED
420 config CPU_HAS_ADDRESS_SPACES
426 config COLDFIRE_SW_A7
429 config HAVE_CACHE_SPLIT
442 int "Set the core clock frequency"
443 default "25000000" if M5206
444 default "54000000" if M5206e
445 default "166666666" if M520x
446 default "140000000" if M5249
447 default "150000000" if M527x || M523x
448 default "90000000" if M5307
449 default "50000000" if M5407
450 default "266000000" if M54xx
454 Define the CPU clock frequency in use. This is the core clock
455 frequency, it may or may not be the same as the external clock
456 crystal fitted to your board. Some processors have an internal
457 PLL and can have their frequency programmed at run time, others
458 use internal dividers. In general the kernel won't setup a PLL
459 if it is fitted (there are some exceptions). This value will be
460 specific to the exact CPU that you are using.
463 bool "Old mask 5307 (1H55J) silicon"
466 Build support for the older revision ColdFire 5307 silicon.
467 Specifically this is the 1H55J mask revision.
471 prompt "Split Cache Configuration"
477 Use all of the ColdFire CPU cache memory as an instruction cache.
482 Use all of the ColdFire CPU cache memory as a data cache.
487 Split the ColdFire CPU cache, and use half as an instruction cache
488 and half as a data cache.
494 prompt "Data cache mode"
495 default CACHE_WRITETHRU
497 config CACHE_WRITETHRU
500 The ColdFire CPU cache is set into Write-through mode.
502 config CACHE_COPYBACK
505 The ColdFire CPU cache is set into Copy-back mode.