path: root/arch/xtensa/Kconfig
diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2013-05-09 14:38:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-05-09 14:38:16 -0700
commitc61c48dfe00907007df3b87e4ed271a5c143bdda (patch)
tree6d26bd3a8b4aa3cf35cad35fa27d1e0afe715db3 /arch/xtensa/Kconfig
parente30f4192456971623b40c97a027346b69457ef69 (diff)
parentb341d84c8ac5ecbf7aa0b3ccd0745d87e881953c (diff)
Merge tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux
Pull xtensa updates from Chris Zankel: "Support for the latest MMU architecture that allows for a larger accessible memory region, and various bug-fixes" * tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux: xtensa: Switch to asm-generic/linkage.h xtensa: fix redboot load address xtensa: ISS: fix timer_lock usage in rs_open xtensa: disable IRQs while IRQ handler is running xtensa: enable lockdep support xtensa: fix arch_irqs_disabled_flags implementation xtensa: add irq flags trace support xtensa: provide custom CALLER_ADDR* implementations xtensa: add stacktrace support xtensa: clean up stpill_registers xtensa: don't use a7 in simcalls xtensa: don't attempt to use unconfigured timers xtensa: provide default platform_pcibios_init implementation xtensa: remove KCORE_ELF again xtensa: document MMUv3 setup sequence xtensa: add MMU v3 support xtensa: fix ibreakenable register update xtensa: fix oprofile building as module
Diffstat (limited to 'arch/xtensa/Kconfig')
1 files changed, 39 insertions, 18 deletions
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index acdfc615cca..0a1b95f81a3 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -1,11 +1,9 @@
- def_bool n
config ZONE_DMA
def_bool y
config XTENSA
def_bool y
select HAVE_IDE
@@ -49,6 +47,15 @@ config HZ
source "init/Kconfig"
source "kernel/Kconfig.freezer"
+ def_bool y
+ def_bool y
+ def_bool y
config MMU
def_bool n
@@ -100,6 +107,35 @@ config MATH_EMULATION
Can we use information of configuration file?
+ bool "Initialize Xtensa MMU inside the Linux kernel code"
+ default y
+ help
+ Earlier version initialized the MMU in the exception vector
+ before jumping to _startup in head.S and had an advantage that
+ it was possible to place a software breakpoint at 'reset' and
+ then enter your normal kernel breakpoints once the MMU was mapped
+ to the kernel mappings (0XC0000000).
+ This unfortunately doesn't work for U-Boot and likley also wont
+ work for using KEXEC to have a hot kernel ready for doing a
+ So now the MMU is initialized in head.S but it's necessary to
+ use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup.
+ xt-gdb can't place a Software Breakpoint in the 0XD region prior
+ to mapping the MMU and after mapping even if the area of low memory
+ was mapped gdb wouldn't remove the breakpoint on hitting it as the
+ PC wouldn't match. Since Hardware Breakpoints are recommended for
+ Linux configurations it seems reasonable to just assume they exist
+ and leave this older mechanism for unfortunate souls that choose
+ not to follow Tensilica's recommendation.
+ Selecting this will cause U-Boot to set the KERNEL Load and Entry
+ address at 0x00003000 instead of the mapped std of 0xD0003000.
+ If in doubt, say Y.
@@ -249,21 +285,6 @@ endmenu
menu "Executable file formats"
-# only elf supported
-config KCORE_ELF
- def_bool y
- depends on PROC_FS
- help
- If you enabled support for /proc file system then the file
- /proc/kcore will contain the kernel core image in ELF format. This
- can be used in gdb:
- $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
- This is especially useful if you have compiled the kernel with the
- "-g" option to preserve debugging information. It is mainly used
- for examining kernel data structures on the live kernel.
source "fs/Kconfig.binfmt"