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_REQUIRE_GPIOLIB
27 select ARCH_HAVE_CUSTOM_GPIO_H
28 select CPU_HAS_NO_BITFIELDS
29 select CPU_HAS_NO_MULDIV64
30 select CPU_HAS_NO_UNALIGNED
39 select CPU_HAS_NO_BITFIELDS
40 select CPU_HAS_NO_MULDIV64
41 select CPU_HAS_NO_UNALIGNED
44 The Freescale (was Motorola) 68000 CPU is the first generation of
45 the well known M68K family of processors. The CPU core as well as
46 being available as a stand alone CPU was also used in many
47 System-On-Chip devices (eg 68328, 68302, etc). It does not contain
52 select CPU_HAS_NO_BITFIELDS
53 select CPU_HAS_NO_UNALIGNED
55 The Freescale (was then Motorola) CPU32 is a CPU core that is
56 based on the 68020 processor. For the most part it is used in
57 System-On-Chip parts, and does not contain a paging MMU.
62 select GENERIC_ATOMIC64
63 select CPU_HAS_ADDRESS_SPACES
65 If you anticipate running this kernel on a computer with a MC68020
66 processor, say Y. Otherwise, say N. Note that the 68020 requires a
67 68851 MMU (Memory Management Unit) to run Linux/m68k, except on the
68 Sun 3, which provides its own version.
72 depends on MMU && !MMU_SUN3
73 select GENERIC_ATOMIC64
74 select CPU_HAS_ADDRESS_SPACES
76 If you anticipate running this kernel on a computer with a MC68030
77 processor, say Y. Otherwise, say N. Note that a MC68EC030 will not
78 work, as it does not include an MMU (Memory Management Unit).
82 depends on MMU && !MMU_SUN3
83 select GENERIC_ATOMIC64
84 select CPU_HAS_ADDRESS_SPACES
86 If you anticipate running this kernel on a computer with a MC68LC040
87 or MC68040 processor, say Y. Otherwise, say N. Note that an
88 MC68EC040 will not work, as it does not include an MMU (Memory
93 depends on MMU && !MMU_SUN3
94 select GENERIC_ATOMIC64
95 select CPU_HAS_ADDRESS_SPACES
97 If you anticipate running this kernel on a computer with a MC68060
98 processor, say Y. Otherwise, say N.
105 Motorola 68328 processor support.
112 Motorola 68EX328 processor support.
119 Motorola 68VZ328 processor support.
126 Motorola 68360 processor support.
135 select COLDFIRE_SW_A7
138 Motorola ColdFire 5206 processor support.
143 select COLDFIRE_SW_A7
146 Motorola ColdFire 5206e processor support.
151 select GENERIC_CLOCKEVENTS
152 select HAVE_CACHE_SPLIT
154 Freescale Coldfire 5207/5208 processor support.
159 select GENERIC_CLOCKEVENTS
160 select HAVE_CACHE_SPLIT
163 Freescale Coldfire 5230/1/2/4/5 processor support
168 select COLDFIRE_SW_A7
171 Motorola ColdFire 5249 processor support.
180 select HAVE_CACHE_SPLIT
182 select GENERIC_CLOCKEVENTS
184 Freescale (Motorola) ColdFire 5270/5271 processor support.
189 select COLDFIRE_SW_A7
192 Motorola ColdFire 5272 processor support.
198 select HAVE_CACHE_SPLIT
200 select GENERIC_CLOCKEVENTS
202 Freescale (Motorola) ColdFire 5274/5275 processor support.
207 select GENERIC_CLOCKEVENTS
208 select HAVE_CACHE_SPLIT
211 Motorola ColdFire 5280/5282 processor support.
216 select COLDFIRE_SW_A7
220 Motorola ColdFire 5307 processor support.
227 Freescale (Motorola) ColdFire 532x processor support.
232 select COLDFIRE_SW_A7
236 Motorola ColdFire 5407 processor support.
244 select MMU_COLDFIRE if MMU
248 Freescale ColdFire 5470/5471/5472/5473/5474/5475 processor support.
252 select MMU_COLDFIRE if MMU
257 Freescale ColdFire 5480/5481/5482/5483/5484/5485 processor support.
262 comment "Processor Specific Options"
265 bool "Math emulation support (EXPERIMENTAL)"
267 depends on EXPERIMENTAL
269 At some point in the future, this will cause floating-point math
270 instructions to be emulated by the kernel on machines that lack a
271 floating-point math coprocessor. Thrill-seekers and chronically
272 sleep-deprived psychotic hacker types can say Y now, everyone else
273 should probably wait a while.
275 config M68KFPU_EMU_EXTRAPREC
276 bool "Math emulation extra precision"
277 depends on M68KFPU_EMU
279 The fpu uses normally a few bit more during calculations for
280 correct rounding, the emulator can (often) do the same but this
281 extra calculation can cost quite some time, so you can disable
282 it here. The emulator will then "only" calculate with a 64 bit
283 mantissa and round slightly incorrect, what is more than enough
286 config M68KFPU_EMU_ONLY
287 bool "Math emulation only kernel"
288 depends on M68KFPU_EMU
290 This option prevents any floating-point instructions from being
291 compiled into the kernel, thereby the kernel doesn't save any
292 floating point context anymore during task switches, so this
293 kernel will only be usable on machines without a floating-point
294 math coprocessor. This makes the kernel a bit faster as no tests
295 needs to be executed whether a floating-point instruction in the
296 kernel should be executed or not.
299 bool "Advanced configuration options"
302 This gives you access to some advanced options for the CPU. The
303 defaults should be fine for most users, but these options may make
304 it possible for you to improve performance somewhat if you know what
307 Note that the answer to this question won't directly affect the
308 kernel: saying N will just cause the configurator to skip all
309 the questions about these options.
311 Most users should say N to this question.
314 bool "Use read-modify-write instructions"
317 This allows to use certain instructions that work with indivisible
318 read-modify-write bus cycles. While this is faster than the
319 workaround of disabling interrupts, it can conflict with DMA
320 ( = direct memory access) on many Amiga systems, and it is also said
321 to destabilize other machines. It is very likely that this will
322 cause serious problems on any Amiga or Atari Medusa if set. The only
323 configuration where it should work are 68030-based Ataris, where it
324 apparently improves performance. But you've been warned! Unless you
325 really know what you are doing, say N. Try Y only if you're quite
328 config SINGLE_MEMORY_CHUNK
329 bool "Use one physical chunk of memory only" if ADVANCED && !SUN3
332 select NEED_MULTIPLE_NODES
334 Ignore all but the first contiguous chunk of physical memory for VM
335 purposes. This will save a few bytes kernel size and may speed up
336 some operations. Say N if not sure.
338 config ARCH_DISCONTIGMEM_ENABLE
339 def_bool MMU && !SINGLE_MEMORY_CHUNK
341 config 060_WRITETHROUGH
342 bool "Use write-through caching for 68060 supervisor accesses"
343 depends on ADVANCED && M68060
345 The 68060 generally uses copyback caching of recently accessed data.
346 Copyback caching means that memory writes will be held in an on-chip
347 cache and only written back to memory some time later. Saying Y
348 here will force supervisor (kernel) accesses to use writethrough
349 caching. Writethrough caching means that data is written to memory
350 straight away, so that cache and memory data always agree.
351 Writethrough caching is less efficient, but is needed for some
352 drivers on 68060 based systems where the 68060 bus snooping signal
353 is hardwired on. The 53c710 SCSI driver is known to suffer from
364 depends on !SINGLE_MEMORY_CHUNK
366 config CPU_HAS_NO_BITFIELDS
369 config CPU_HAS_NO_MULDIV64
372 config CPU_HAS_NO_UNALIGNED
375 config CPU_HAS_ADDRESS_SPACES
381 config COLDFIRE_SW_A7
384 config HAVE_CACHE_SPLIT
397 bool "Enable setting the CPU clock frequency"
401 On some CPU's you do not need to know what the core CPU clock
402 frequency is. On these you can disable clock setting. On some
403 traditional 68K parts, and on all ColdFire parts you need to set
404 the appropriate CPU clock frequency. On these devices many of the
405 onboard peripherals derive their timing from the master CPU clock
409 int "Set the core clock frequency"
413 Define the CPU clock frequency in use. This is the core clock
414 frequency, it may or may not be the same as the external clock
415 crystal fitted to your board. Some processors have an internal
416 PLL and can have their frequency programmed at run time, others
417 use internal dividers. In general the kernel won't setup a PLL
418 if it is fitted (there are some exceptions). This value will be
419 specific to the exact CPU that you are using.
422 bool "Old mask 5307 (1H55J) silicon"
425 Build support for the older revision ColdFire 5307 silicon.
426 Specifically this is the 1H55J mask revision.
430 prompt "Split Cache Configuration"
436 Use all of the ColdFire CPU cache memory as an instruction cache.
441 Use all of the ColdFire CPU cache memory as a data cache.
446 Split the ColdFire CPU cache, and use half as an instruction cache
447 and half as a data cache.
453 prompt "Data cache mode"
454 default CACHE_WRITETHRU
456 config CACHE_WRITETHRU
459 The ColdFire CPU cache is set into Write-through mode.
461 config CACHE_COPYBACK
464 The ColdFire CPU cache is set into Copy-back mode.