1 # SPDX-License-Identifier: GPL-2.0
2 menu "Processor features"
5 prompt "Endianness selection"
6 default CPU_LITTLE_ENDIAN
8 Some SuperH machines can be configured for either little or big
9 endian byte order. These modes require different kernels.
11 config CPU_LITTLE_ENDIAN
22 depends on CPU_HAS_FPU
24 Selecting this option will enable support for SH processors that
25 have FPU units (ie, SH77xx).
27 This option must be set in order to enable the FPU.
31 prompt "FPU emulation support"
34 Selecting this option will enable support for software FPU emulation.
35 Most SH-3 users will want to say Y here, whereas most SH-4 users will
41 depends on CPU_HAS_DSP
43 Selecting this option will enable support for SH processors that
44 have DSP units (ie, SH2-DSP, SH3-DSP, and SH4AL-DSP).
46 This option must be set in order to enable the DSP.
53 Selecting this option will allow the Linux kernel to use SH3 on-chip
58 config SH_STORE_QUEUES
59 bool "Support for Store Queues"
62 Selecting this option will enable an in-kernel API for manipulating
63 the store queues integrated in the SH-4 processors.
65 config SPECULATIVE_EXECUTION
66 bool "Speculative subroutine return"
67 depends on CPU_SUBTYPE_SH7780 || CPU_SUBTYPE_SH7785 || CPU_SUBTYPE_SH7786
69 This enables support for a speculative instruction fetch for
70 subroutine return. There are various pitfalls associated with
71 this, as outlined in the SH7780 hardware manual.
78 config CPU_HAS_IPR_IRQ
84 This will enable the use of SR.RB register bank usage. Processors
85 that are lacking this bit must have another method in place for
86 accomplishing what is taken care of by the banked registers.
88 See <file:Documentation/arch/sh/register-banks.rst> for further
89 information on SR.RB and register banking in the kernel in general.