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
42 The Freescale (was Motorola) 68000 CPU is the first generation of
43 the well known M68K family of processors. The CPU core as well as
44 being available as a stand alone CPU was also used in many
45 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
50 select CPU_HAS_NO_BITFIELDS
52 The Freescale (was then Motorola) CPU32 is a CPU core that is
53 based on the 68020 processor. For the most part it is used in
54 System-On-Chip parts, and does not contain a paging MMU.
59 select GENERIC_ATOMIC64
60 select CPU_HAS_ADDRESS_SPACES
62 If you anticipate running this kernel on a computer with a MC68020
63 processor, say Y. Otherwise, say N. Note that the 68020 requires a
64 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
65 Sun 3, which provides its own version.
69 depends on MMU && !MMU_SUN3
70 select GENERIC_ATOMIC64
71 select CPU_HAS_ADDRESS_SPACES
73 If you anticipate running this kernel on a computer with a MC68030
74 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
75 work, as it does not include an MMU (Memory Management Unit).
79 depends on MMU && !MMU_SUN3
80 select GENERIC_ATOMIC64
81 select CPU_HAS_ADDRESS_SPACES
83 If you anticipate running this kernel on a computer with a MC68LC040
84 or MC68040 processor, say Y. Otherwise, say N. Note that an
85 MC68EC040 will not work, as it does not include an MMU (Memory
90 depends on MMU && !MMU_SUN3
91 select GENERIC_ATOMIC64
92 select CPU_HAS_ADDRESS_SPACES
94 If you anticipate running this kernel on a computer with a MC68060
95 processor, say Y. Otherwise, say N.
102 Motorola 68328 processor support.
109 Motorola 68EX328 processor support.
116 Motorola 68VZ328 processor support.
123 Motorola 68360 processor support.
132 select COLDFIRE_SW_A7
135 Motorola ColdFire 5206 processor support.
140 select COLDFIRE_SW_A7
143 Motorola ColdFire 5206e processor support.
148 select GENERIC_CLOCKEVENTS
149 select HAVE_CACHE_SPLIT
151 Freescale Coldfire 5207/5208 processor support.
156 select GENERIC_CLOCKEVENTS
157 select HAVE_CACHE_SPLIT
160 Freescale Coldfire 5230/1/2/4/5 processor support
165 select COLDFIRE_SW_A7
168 Motorola ColdFire 5249 processor support.
173 select COLDFIRE_SW_A7
176 Freescale (Motorola) Coldfire 5251/5253 processor support.
185 select HAVE_CACHE_SPLIT
187 select GENERIC_CLOCKEVENTS
189 Freescale (Motorola) ColdFire 5270/5271 processor support.
194 select COLDFIRE_SW_A7
197 Motorola ColdFire 5272 processor support.
203 select HAVE_CACHE_SPLIT
205 select GENERIC_CLOCKEVENTS
207 Freescale (Motorola) ColdFire 5274/5275 processor support.
212 select GENERIC_CLOCKEVENTS
213 select HAVE_CACHE_SPLIT
216 Motorola ColdFire 5280/5282 processor support.
221 select COLDFIRE_SW_A7
225 Motorola ColdFire 5307 processor support.
232 Freescale (Motorola) ColdFire 532x processor support.
237 select COLDFIRE_SW_A7
241 Motorola ColdFire 5407 processor support.
249 select MMU_COLDFIRE if MMU
253 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
257 select MMU_COLDFIRE if MMU
262 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
267 select GENERIC_CLOCKEVENTS
270 Freescale Coldfire 54410/54415/54416/54417/54418 processor support.
275 comment "Processor Specific Options"
278 bool "Math emulation support (EXPERIMENTAL)"
280 depends on EXPERIMENTAL
282 At some point in the future, this will cause floating-point math
283 instructions to be emulated by the kernel on machines that lack a
284 floating-point math coprocessor. Thrill-seekers and chronically
285 sleep-deprived psychotic hacker types can say Y now, everyone else
286 should probably wait a while.
288 config M68KFPU_EMU_EXTRAPREC
289 bool "Math emulation extra precision"
290 depends on M68KFPU_EMU
292 The fpu uses normally a few bit more during calculations for
293 correct rounding, the emulator can (often) do the same but this
294 extra calculation can cost quite some time, so you can disable
295 it here. The emulator will then "only" calculate with a 64 bit
296 mantissa and round slightly incorrect, what is more than enough
299 config M68KFPU_EMU_ONLY
300 bool "Math emulation only kernel"
301 depends on M68KFPU_EMU
303 This option prevents any floating-point instructions from being
304 compiled into the kernel, thereby the kernel doesn't save any
305 floating point context anymore during task switches, so this
306 kernel will only be usable on machines without a floating-point
307 math coprocessor. This makes the kernel a bit faster as no tests
308 needs to be executed whether a floating-point instruction in the
309 kernel should be executed or not.
312 bool "Advanced configuration options"
315 This gives you access to some advanced options for the CPU. The
316 defaults should be fine for most users, but these options may make
317 it possible for you to improve performance somewhat if you know what
320 Note that the answer to this question won't directly affect the
321 kernel: saying N will just cause the configurator to skip all
322 the questions about these options.
324 Most users should say N to this question.
327 bool "Use read-modify-write instructions"
330 This allows to use certain instructions that work with indivisible
331 read-modify-write bus cycles. While this is faster than the
332 workaround of disabling interrupts, it can conflict with DMA
333 ( = direct memory access) on many Amiga systems, and it is also said
334 to destabilize other machines. It is very likely that this will
335 cause serious problems on any Amiga or Atari Medusa if set. The only
336 configuration where it should work are 68030-based Ataris, where it
337 apparently improves performance. But you've been warned! Unless you
338 really know what you are doing, say N. Try Y only if you're quite
341 config SINGLE_MEMORY_CHUNK
342 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
345 select NEED_MULTIPLE_NODES
347 Ignore all but the first contiguous chunk of physical memory for VM
348 purposes. This will save a few bytes kernel size and may speed up
349 some operations. Say N if not sure.
351 config ARCH_DISCONTIGMEM_ENABLE
352 def_bool MMU && !SINGLE_MEMORY_CHUNK
354 config 060_WRITETHROUGH
355 bool "Use write-through caching for 68060 supervisor accesses"
356 depends on ADVANCED && M68060
358 The 68060 generally uses copyback caching of recently accessed data.
359 Copyback caching means that memory writes will be held in an on-chip
360 cache and only written back to memory some time later. Saying Y
361 here will force supervisor (kernel) accesses to use writethrough
362 caching. Writethrough caching means that data is written to memory
363 straight away, so that cache and memory data always agree.
364 Writethrough caching is less efficient, but is needed for some
365 drivers on 68060 based systems where the 68060 bus snooping signal
366 is hardwired on. The 53c710 SCSI driver is known to suffer from
377 depends on !SINGLE_MEMORY_CHUNK
382 config COLDFIRE_SW_A7
385 config HAVE_CACHE_SPLIT
398 bool "Enable setting the CPU clock frequency"
402 On some CPU's you do not need to know what the core CPU clock
403 frequency is. On these you can disable clock setting. On some
404 traditional 68K parts, and on all ColdFire parts you need to set
405 the appropriate CPU clock frequency. On these devices many of the
406 onboard peripherals derive their timing from the master CPU clock
410 int "Set the core clock frequency"
414 Define the CPU clock frequency in use. This is the core clock
415 frequency, it may or may not be the same as the external clock
416 crystal fitted to your board. Some processors have an internal
417 PLL and can have their frequency programmed at run time, others
418 use internal dividers. In general the kernel won't setup a PLL
419 if it is fitted (there are some exceptions). This value will be
420 specific to the exact CPU that you are using.
423 bool "Old mask 5307 (1H55J) silicon"
426 Build support for the older revision ColdFire 5307 silicon.
427 Specifically this is the 1H55J mask revision.
431 prompt "Split Cache Configuration"
437 Use all of the ColdFire CPU cache memory as an instruction cache.
442 Use all of the ColdFire CPU cache memory as a data cache.
447 Split the ColdFire CPU cache, and use half as an instruction cache
448 and half as a data cache.
454 prompt "Data cache mode"
455 default CACHE_WRITETHRU
457 config CACHE_WRITETHRU
460 The ColdFire CPU cache is set into Write-through mode.
462 config CACHE_COPYBACK
465 The ColdFire CPU cache is set into Copy-back mode.