1 comment "Processor Type"
4 prompt "CPU family support"
5 default M68KCLASSIC if MMU
6 default COLDFIRE if !MMU
8 The Freescale (was Motorola) M68K family of processors implements
9 the full 68000 processor instruction set.
10 The Freescale ColdFire family of processors is a modern derivative
11 of the 68000 processor family. They are mainly targeted at embedded
12 applications, and are all System-On-Chip (SOC) devices, as opposed
13 to stand alone CPUs. They implement a subset of the original 68000
14 processor instruction set.
15 If you anticipate running this kernel on a computer with a classic
16 MC68xxx processor, select M68KCLASSIC.
17 If you anticipate running this kernel on a computer with a ColdFire
18 processor, select COLDFIRE.
21 bool "Classic M68K CPU family support"
24 bool "Coldfire CPU family support"
26 select ARCH_WANT_OPTIONAL_GPIOLIB
27 select ARCH_HAVE_CUSTOM_GPIO_H
28 select CPU_HAS_NO_BITFIELDS
29 select CPU_HAS_NO_MULDIV64
38 select CPU_HAS_NO_BITFIELDS
39 select CPU_HAS_NO_MULDIV64
40 select CPU_HAS_NO_UNALIGNED
43 The Freescale (was Motorola) 68000 CPU is the first generation of
44 the well known M68K family of processors. The CPU core as well as
45 being available as a stand alone CPU was also used in many
46 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
51 select CPU_HAS_NO_BITFIELDS
52 select CPU_HAS_NO_UNALIGNED
54 The Freescale (was then Motorola) CPU32 is a CPU core that is
55 based on the 68020 processor. For the most part it is used in
56 System-On-Chip parts, and does not contain a paging MMU.
61 select GENERIC_ATOMIC64
62 select CPU_HAS_ADDRESS_SPACES
64 If you anticipate running this kernel on a computer with a MC68020
65 processor, say Y. Otherwise, say N. Note that the 68020 requires a
66 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
67 Sun 3, which provides its own version.
71 depends on MMU && !MMU_SUN3
72 select GENERIC_ATOMIC64
73 select CPU_HAS_ADDRESS_SPACES
75 If you anticipate running this kernel on a computer with a MC68030
76 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
77 work, as it does not include an MMU (Memory Management Unit).
81 depends on MMU && !MMU_SUN3
82 select GENERIC_ATOMIC64
83 select CPU_HAS_ADDRESS_SPACES
85 If you anticipate running this kernel on a computer with a MC68LC040
86 or MC68040 processor, say Y. Otherwise, say N. Note that an
87 MC68EC040 will not work, as it does not include an MMU (Memory
92 depends on MMU && !MMU_SUN3
93 select GENERIC_ATOMIC64
94 select CPU_HAS_ADDRESS_SPACES
96 If you anticipate running this kernel on a computer with a MC68060
97 processor, say Y. Otherwise, say N.
104 Motorola 68328 processor support.
111 Motorola 68EX328 processor support.
118 Motorola 68VZ328 processor support.
125 Motorola 68360 processor support.
134 select COLDFIRE_SW_A7
137 Motorola ColdFire 5206 processor support.
142 select COLDFIRE_SW_A7
145 Motorola ColdFire 5206e processor support.
150 select GENERIC_CLOCKEVENTS
151 select HAVE_CACHE_SPLIT
153 Freescale Coldfire 5207/5208 processor support.
158 select GENERIC_CLOCKEVENTS
159 select HAVE_CACHE_SPLIT
162 Freescale Coldfire 5230/1/2/4/5 processor support
167 select COLDFIRE_SW_A7
170 Motorola ColdFire 5249 processor support.
175 select COLDFIRE_SW_A7
178 Freescale (Motorola) Coldfire 5251/5253 processor support.
187 select HAVE_CACHE_SPLIT
189 select GENERIC_CLOCKEVENTS
191 Freescale (Motorola) ColdFire 5270/5271 processor support.
196 select COLDFIRE_SW_A7
199 Motorola ColdFire 5272 processor support.
205 select HAVE_CACHE_SPLIT
207 select GENERIC_CLOCKEVENTS
209 Freescale (Motorola) ColdFire 5274/5275 processor support.
214 select GENERIC_CLOCKEVENTS
215 select HAVE_CACHE_SPLIT
218 Motorola ColdFire 5280/5282 processor support.
223 select COLDFIRE_SW_A7
227 Motorola ColdFire 5307 processor support.
234 Freescale (Motorola) ColdFire 532x processor support.
239 select COLDFIRE_SW_A7
243 Motorola ColdFire 5407 processor support.
251 select MMU_COLDFIRE if MMU
255 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
259 select MMU_COLDFIRE if MMU
264 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
269 select GENERIC_CLOCKEVENTS
272 Freescale Coldfire 54410/54415/54416/54417/54418 processor support.
277 comment "Processor Specific Options"
280 bool "Math emulation support (EXPERIMENTAL)"
282 depends on EXPERIMENTAL
284 At some point in the future, this will cause floating-point math
285 instructions to be emulated by the kernel on machines that lack a
286 floating-point math coprocessor. Thrill-seekers and chronically
287 sleep-deprived psychotic hacker types can say Y now, everyone else
288 should probably wait a while.
290 config M68KFPU_EMU_EXTRAPREC
291 bool "Math emulation extra precision"
292 depends on M68KFPU_EMU
294 The fpu uses normally a few bit more during calculations for
295 correct rounding, the emulator can (often) do the same but this
296 extra calculation can cost quite some time, so you can disable
297 it here. The emulator will then "only" calculate with a 64 bit
298 mantissa and round slightly incorrect, what is more than enough
301 config M68KFPU_EMU_ONLY
302 bool "Math emulation only kernel"
303 depends on M68KFPU_EMU
305 This option prevents any floating-point instructions from being
306 compiled into the kernel, thereby the kernel doesn't save any
307 floating point context anymore during task switches, so this
308 kernel will only be usable on machines without a floating-point
309 math coprocessor. This makes the kernel a bit faster as no tests
310 needs to be executed whether a floating-point instruction in the
311 kernel should be executed or not.
314 bool "Advanced configuration options"
317 This gives you access to some advanced options for the CPU. The
318 defaults should be fine for most users, but these options may make
319 it possible for you to improve performance somewhat if you know what
322 Note that the answer to this question won't directly affect the
323 kernel: saying N will just cause the configurator to skip all
324 the questions about these options.
326 Most users should say N to this question.
329 bool "Use read-modify-write instructions"
332 This allows to use certain instructions that work with indivisible
333 read-modify-write bus cycles. While this is faster than the
334 workaround of disabling interrupts, it can conflict with DMA
335 ( = direct memory access) on many Amiga systems, and it is also said
336 to destabilize other machines. It is very likely that this will
337 cause serious problems on any Amiga or Atari Medusa if set. The only
338 configuration where it should work are 68030-based Ataris, where it
339 apparently improves performance. But you've been warned! Unless you
340 really know what you are doing, say N. Try Y only if you're quite
343 config SINGLE_MEMORY_CHUNK
344 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
347 select NEED_MULTIPLE_NODES
349 Ignore all but the first contiguous chunk of physical memory for VM
350 purposes. This will save a few bytes kernel size and may speed up
351 some operations. Say N if not sure.
353 config ARCH_DISCONTIGMEM_ENABLE
354 def_bool MMU && !SINGLE_MEMORY_CHUNK
356 config 060_WRITETHROUGH
357 bool "Use write-through caching for 68060 supervisor accesses"
358 depends on ADVANCED && M68060
360 The 68060 generally uses copyback caching of recently accessed data.
361 Copyback caching means that memory writes will be held in an on-chip
362 cache and only written back to memory some time later. Saying Y
363 here will force supervisor (kernel) accesses to use writethrough
364 caching. Writethrough caching means that data is written to memory
365 straight away, so that cache and memory data always agree.
366 Writethrough caching is less efficient, but is needed for some
367 drivers on 68060 based systems where the 68060 bus snooping signal
368 is hardwired on. The 53c710 SCSI driver is known to suffer from
379 depends on !SINGLE_MEMORY_CHUNK
381 config CPU_HAS_NO_BITFIELDS
384 config CPU_HAS_NO_MULDIV64
387 config CPU_HAS_NO_UNALIGNED
390 config CPU_HAS_ADDRESS_SPACES
396 config COLDFIRE_SW_A7
399 config HAVE_CACHE_SPLIT
412 bool "Enable setting the CPU clock frequency"
416 On some CPU's you do not need to know what the core CPU clock
417 frequency is. On these you can disable clock setting. On some
418 traditional 68K parts, and on all ColdFire parts you need to set
419 the appropriate CPU clock frequency. On these devices many of the
420 onboard peripherals derive their timing from the master CPU clock
424 int "Set the core clock frequency"
428 Define the CPU clock frequency in use. This is the core clock
429 frequency, it may or may not be the same as the external clock
430 crystal fitted to your board. Some processors have an internal
431 PLL and can have their frequency programmed at run time, others
432 use internal dividers. In general the kernel won't setup a PLL
433 if it is fitted (there are some exceptions). This value will be
434 specific to the exact CPU that you are using.
437 bool "Old mask 5307 (1H55J) silicon"
440 Build support for the older revision ColdFire 5307 silicon.
441 Specifically this is the 1H55J mask revision.
445 prompt "Split Cache Configuration"
451 Use all of the ColdFire CPU cache memory as an instruction cache.
456 Use all of the ColdFire CPU cache memory as a data cache.
461 Split the ColdFire CPU cache, and use half as an instruction cache
462 and half as a data cache.
468 prompt "Data cache mode"
469 default CACHE_WRITETHRU
471 config CACHE_WRITETHRU
474 The ColdFire CPU cache is set into Write-through mode.
476 config CACHE_COPYBACK
479 The ColdFire CPU cache is set into Copy-back mode.