1 # SPDX-License-Identifier: GPL-2.0
3 config SH_STANDARD_BIOS
4 bool "Use LinuxSH standard BIOS"
6 Say Y here if your target has the gdb-sh-stub
7 package from www.m17n.org (or any conforming standard LinuxSH BIOS)
8 in FLASH or EPROM. The kernel will use standard BIOS calls during
9 boot for various housekeeping tasks (including calls to read and
10 write characters to a system console, get a MAC address from an
11 on-board Ethernet interface, and shut down the hardware). Note this
12 does not work with machines with an existing operating system in
13 mask ROM and no flash (WindowsCE machines fall in this category).
17 bool "Check for stack overflows"
18 depends on DEBUG_KERNEL && PRINTK
20 This option will cause messages to be printed if free stack space
21 drops below a certain limit. Saying Y here will add overhead to
22 every function call and will therefore incur a major
23 performance hit. Most users should say N.
27 depends on SH_STANDARD_BIOS
29 Say Y here to redirect kernel printk messages to the serial port
30 used by the SH-IPL bootloader, starting very early in the boot
31 process and ending when the kernel's serial console is initialised.
32 This option is only useful while porting the kernel to a new machine,
33 when the kernel may crash or hang before the serial console is
34 initialised. If unsure, say N.
37 bool "Use 4Kb for kernel stacks instead of 8Kb"
38 depends on DEBUG_KERNEL && (MMU || BROKEN) && !PAGE_SIZE_64KB
40 If you say Y here the kernel will use a 4Kb stacksize for the
41 kernel stack attached to each process/thread. This facilitates
42 running more threads on a system and also reduces the pressure
43 on the VM subsystem for higher order allocations. This option
44 will also use IRQ stacks to compensate for the reduced stackspace.
47 bool "Use separate kernel stacks when processing interrupts"
48 depends on DEBUG_KERNEL && BROKEN
50 If you say Y here the kernel will use separate kernel stacks
51 for handling hard and soft interrupts. This can help avoid
52 overflowing the process kernel stacks.
55 bool "Show disassembly of nearby code in register dumps"
56 depends on DEBUG_KERNEL
57 default y if DEBUG_BUGVERBOSE
60 This prints out a code trace of the instructions leading up to
61 the faulting instruction as a debugging aid. As this does grow
62 the kernel in size a bit, most users will want to say N here.
64 Those looking for more verbose debugging output should say Y.
67 bool "Enable the DWARF unwinder for stacktraces"
68 depends on DEBUG_KERNEL
72 Enabling this option will make stacktraces more accurate, at
73 the cost of an increase in overall kernel size.
76 bool "Avoid zeroing BSS (to speed-up startup on suitable platforms)"
77 depends on DEBUG_KERNEL
80 If running in painfully slow environments, such as an RTL
81 simulation or from remote memory via SHdebug, where the memory
82 can already be guaranteed to ber zeroed on boot, say Y.
84 For all other cases, say N. If this option seems perplexing, or
85 you aren't sure, say N.
89 depends on STACK_DEBUG || FUNCTION_TRACER