2005-04-17 06:20:36 +08:00
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#
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# Makefile for the Linux/MIPS kernel.
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#
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2012-05-03 17:02:55 +08:00
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extra-y := head.o vmlinux.lds
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2005-04-17 06:20:36 +08:00
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2014-09-11 15:30:22 +08:00
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obj-y += cpu-probe.o branch.o elf.o entry.o genex.o idle.o irq.o \
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process.o prom.o ptrace.o reset.o setup.o signal.o \
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syscall.o time.o topology.o traps.o unaligned.o watch.o \
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2016-12-08 09:16:26 +08:00
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vdso.o cacheinfo.o
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2005-04-17 06:20:36 +08:00
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2009-11-20 20:34:29 +08:00
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ifdef CONFIG_FUNCTION_TRACER
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MIPS: Tracing: Add dynamic function tracer support
With dynamic function tracer, by default, _mcount is defined as an
"empty" function, it returns directly without any more action . When
enabling it in user-space, it will jump to a real tracing
function(ftrace_caller), and do the real job for us.
Differ from the static function tracer, dynamic function tracer provides
two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the
tracing of some indicated kernel functions(set_ftrace_filter).
In the -v4 version, the implementation of this support is basically the same as
X86 version does: _mcount is implemented as an empty function and ftrace_caller
is implemented as a real tracing function respectively.
But in this version, to support module tracing with the help of
-mlong-calls in arch/mips/Makefile:
MODFLAGS += -mlong-calls.
The stuff becomes a little more complex. We need to cope with two
different type of calling to _mcount.
For the kernel part, the calling to _mcount(result of "objdump -hdr
vmlinux"). is like this:
108: 03e0082d move at,ra
10c: 0c000000 jal 0 <fpcsr_pending>
10c: R_MIPS_26 _mcount
10c: R_MIPS_NONE *ABS*
10c: R_MIPS_NONE *ABS*
110: 00020021 nop
For the module with -mlong-calls, it looks like this:
c: 3c030000 lui v1,0x0
c: R_MIPS_HI16 _mcount
c: R_MIPS_NONE *ABS*
c: R_MIPS_NONE *ABS*
10: 64630000 daddiu v1,v1,0
10: R_MIPS_LO16 _mcount
10: R_MIPS_NONE *ABS*
10: R_MIPS_NONE *ABS*
14: 03e0082d move at,ra
18: 0060f809 jalr v1
In the kernel version, there is only one "_mcount" string for every
kernel function, so, we just need to match this one in mcount_regex of
scripts/recordmcount.pl, but in the module version, we need to choose
one of the two to match. Herein, I choose the first one with
"R_MIPS_HI16 _mcount".
and In the kernel verion, without module tracing support, we just need
to replace "jal _mcount" by "jal ftrace_caller" to do real tracing, and
filter the tracing of some kernel functions via replacing it by a nop
instruction.
but as we have described before, the instruction "jal ftrace_caller" only left
32bit length for the address of ftrace_caller, it will fail when calling from
the module space. so, herein, we must replace something else.
the basic idea is loading the address of ftrace_caller to v1 via changing these
two instructions:
lui v1,0x0
addiu v1,v1,0
If we want to enable the tracing, we need to replace the above instructions to:
lui v1, HI_16BIT_ftrace_caller
addiu v1, v1, LOW_16BIT_ftrace_caller
If we want to stop the tracing of the indicated kernel functions, we
just need to replace the "jalr v1" to a nop instruction. but we need to
replace two instructions and encode the above two instructions
oursevles.
Is there a simpler solution? Yes! Here it is, in this version, we put _mcount
and ftrace_caller together, which means the address of _mcount and
ftrace_caller is the same:
_mcount:
ftrace_caller:
j ftrace_stub
nop
...(do real tracing here)...
ftrace_stub:
jr ra
move ra, at
By default, the kernel functions call _mcount, and then jump to ftrace_stub and
return. and when we want to do real tracing, we just need to remove that "j
ftrace_stub", and it will run through the two "nop" instructions and then do
the real tracing job.
what about filtering job? we just need to do this:
lui v1, hi_16bit_of_mcount <--> b 1f (0x10000004)
addiu v1, v1, low_16bit_of_mcount
move at, ra
jalr v1
nop
1f: (rec->ip + 12)
In linux-mips64, there will be some local symbols, whose name are
prefixed by $L, which need to be filtered. thanks goes to Steven for
writing the mips64-specific function_regex.
In a conclusion, with RISC, things becomes easier with such a "stupid"
trick, RISC is something like K.I.S.S, and also, there are lots of
"simple" tricks in the whole ftrace support, thanks goes to Steven and
the other folks for providing such a wonderful tracing framework!
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: zhangfx@lemote.com
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/675/
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-11-20 20:34:32 +08:00
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CFLAGS_REMOVE_ftrace.o = -pg
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2009-11-20 20:34:29 +08:00
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CFLAGS_REMOVE_early_printk.o = -pg
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2011-09-24 08:29:55 +08:00
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CFLAGS_REMOVE_perf_event.o = -pg
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CFLAGS_REMOVE_perf_event_mipsxx.o = -pg
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2009-11-20 20:34:29 +08:00
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endif
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2007-11-01 09:57:55 +08:00
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obj-$(CONFIG_CEVT_BCM1480) += cevt-bcm1480.o
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2012-12-01 00:27:27 +08:00
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obj-$(CONFIG_CEVT_R4K) += cevt-r4k.o
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2008-04-25 11:11:44 +08:00
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obj-$(CONFIG_CEVT_DS1287) += cevt-ds1287.o
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2007-10-22 18:43:15 +08:00
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obj-$(CONFIG_CEVT_GT641XX) += cevt-gt641xx.o
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2007-11-01 09:57:55 +08:00
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obj-$(CONFIG_CEVT_SB1250) += cevt-sb1250.o
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2007-10-25 00:34:09 +08:00
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obj-$(CONFIG_CEVT_TXX9) += cevt-txx9.o
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2007-11-01 09:57:55 +08:00
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obj-$(CONFIG_CSRC_BCM1480) += csrc-bcm1480.o
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2008-04-24 08:48:40 +08:00
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obj-$(CONFIG_CSRC_IOASIC) += csrc-ioasic.o
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2012-11-15 13:34:17 +08:00
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obj-$(CONFIG_CSRC_R4K) += csrc-r4k.o
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2007-11-01 09:57:55 +08:00
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obj-$(CONFIG_CSRC_SB1250) += csrc-sb1250.o
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2008-04-29 00:14:26 +08:00
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obj-$(CONFIG_SYNC_R4K) += sync-r4k.o
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2007-10-19 00:48:11 +08:00
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2013-11-15 00:12:32 +08:00
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obj-$(CONFIG_DEBUG_FS) += segment.o
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2006-09-26 22:44:01 +08:00
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obj-$(CONFIG_STACKTRACE) += stacktrace.o
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2016-11-07 19:14:16 +08:00
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obj-$(CONFIG_MODULES) += module.o
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2012-09-28 13:01:03 +08:00
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obj-$(CONFIG_MODULES_USE_ELF_RELA) += module-rela.o
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2005-04-17 06:20:36 +08:00
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2012-07-14 05:38:17 +08:00
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obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
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MIPS: Tracing: Add dynamic function tracer support
With dynamic function tracer, by default, _mcount is defined as an
"empty" function, it returns directly without any more action . When
enabling it in user-space, it will jump to a real tracing
function(ftrace_caller), and do the real job for us.
Differ from the static function tracer, dynamic function tracer provides
two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the
tracing of some indicated kernel functions(set_ftrace_filter).
In the -v4 version, the implementation of this support is basically the same as
X86 version does: _mcount is implemented as an empty function and ftrace_caller
is implemented as a real tracing function respectively.
But in this version, to support module tracing with the help of
-mlong-calls in arch/mips/Makefile:
MODFLAGS += -mlong-calls.
The stuff becomes a little more complex. We need to cope with two
different type of calling to _mcount.
For the kernel part, the calling to _mcount(result of "objdump -hdr
vmlinux"). is like this:
108: 03e0082d move at,ra
10c: 0c000000 jal 0 <fpcsr_pending>
10c: R_MIPS_26 _mcount
10c: R_MIPS_NONE *ABS*
10c: R_MIPS_NONE *ABS*
110: 00020021 nop
For the module with -mlong-calls, it looks like this:
c: 3c030000 lui v1,0x0
c: R_MIPS_HI16 _mcount
c: R_MIPS_NONE *ABS*
c: R_MIPS_NONE *ABS*
10: 64630000 daddiu v1,v1,0
10: R_MIPS_LO16 _mcount
10: R_MIPS_NONE *ABS*
10: R_MIPS_NONE *ABS*
14: 03e0082d move at,ra
18: 0060f809 jalr v1
In the kernel version, there is only one "_mcount" string for every
kernel function, so, we just need to match this one in mcount_regex of
scripts/recordmcount.pl, but in the module version, we need to choose
one of the two to match. Herein, I choose the first one with
"R_MIPS_HI16 _mcount".
and In the kernel verion, without module tracing support, we just need
to replace "jal _mcount" by "jal ftrace_caller" to do real tracing, and
filter the tracing of some kernel functions via replacing it by a nop
instruction.
but as we have described before, the instruction "jal ftrace_caller" only left
32bit length for the address of ftrace_caller, it will fail when calling from
the module space. so, herein, we must replace something else.
the basic idea is loading the address of ftrace_caller to v1 via changing these
two instructions:
lui v1,0x0
addiu v1,v1,0
If we want to enable the tracing, we need to replace the above instructions to:
lui v1, HI_16BIT_ftrace_caller
addiu v1, v1, LOW_16BIT_ftrace_caller
If we want to stop the tracing of the indicated kernel functions, we
just need to replace the "jalr v1" to a nop instruction. but we need to
replace two instructions and encode the above two instructions
oursevles.
Is there a simpler solution? Yes! Here it is, in this version, we put _mcount
and ftrace_caller together, which means the address of _mcount and
ftrace_caller is the same:
_mcount:
ftrace_caller:
j ftrace_stub
nop
...(do real tracing here)...
ftrace_stub:
jr ra
move ra, at
By default, the kernel functions call _mcount, and then jump to ftrace_stub and
return. and when we want to do real tracing, we just need to remove that "j
ftrace_stub", and it will run through the two "nop" instructions and then do
the real tracing job.
what about filtering job? we just need to do this:
lui v1, hi_16bit_of_mcount <--> b 1f (0x10000004)
addiu v1, v1, low_16bit_of_mcount
move at, ra
jalr v1
nop
1f: (rec->ip + 12)
In linux-mips64, there will be some local symbols, whose name are
prefixed by $L, which need to be filtered. thanks goes to Steven for
writing the mips64-specific function_regex.
In a conclusion, with RISC, things becomes easier with such a "stupid"
trick, RISC is something like K.I.S.S, and also, there are lots of
"simple" tricks in the whole ftrace support, thanks goes to Steven and
the other folks for providing such a wonderful tracing framework!
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: zhangfx@lemote.com
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/675/
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-11-20 20:34:32 +08:00
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obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o
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2009-11-20 20:34:29 +08:00
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2012-02-01 01:18:44 +08:00
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obj-$(CONFIG_CPU_R4K_FPU) += r4k_fpu.o r4k_switch.o
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2005-04-17 06:20:36 +08:00
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obj-$(CONFIG_CPU_R3000) += r2300_fpu.o r2300_switch.o
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2007-06-06 14:52:43 +08:00
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obj-$(CONFIG_CPU_R6000) += r6000_fpu.o r4k_switch.o
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obj-$(CONFIG_CPU_TX39XX) += r2300_fpu.o r2300_switch.o
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2014-05-29 05:52:04 +08:00
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obj-$(CONFIG_CPU_CAVIUM_OCTEON) += r4k_fpu.o octeon_switch.o
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2005-04-17 06:20:36 +08:00
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obj-$(CONFIG_SMP) += smp.o
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2007-11-25 06:33:28 +08:00
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obj-$(CONFIG_SMP_UP) += smp-up.o
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2016-02-04 10:14:50 +08:00
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obj-$(CONFIG_CPU_BMIPS) += smp-bmips.o bmips_vec.o bmips_5xxx_init.o
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2005-04-17 06:20:36 +08:00
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2006-04-05 16:45:45 +08:00
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obj-$(CONFIG_MIPS_MT) += mips-mt.o
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2007-07-03 21:37:43 +08:00
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obj-$(CONFIG_MIPS_MT_FPAFF) += mips-mt-fpaff.o
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2006-04-05 16:45:45 +08:00
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obj-$(CONFIG_MIPS_MT_SMP) += smp-mt.o
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2008-04-29 00:14:26 +08:00
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obj-$(CONFIG_MIPS_CMP) += smp-cmp.o
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2014-01-15 18:31:53 +08:00
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obj-$(CONFIG_MIPS_CPS) += smp-cps.o cps-vec.o
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2015-09-23 02:12:11 +08:00
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obj-$(CONFIG_MIPS_CPS_NS16550) += cps-vec-ns16550.o
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2014-11-13 21:32:03 +08:00
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obj-$(CONFIG_MIPS_SPRAM) += spram.o
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2005-08-18 01:44:08 +08:00
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2005-07-14 23:57:16 +08:00
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obj-$(CONFIG_MIPS_VPE_LOADER) += vpe.o
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2013-10-31 04:52:07 +08:00
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obj-$(CONFIG_MIPS_VPE_LOADER_CMP) += vpe-cmp.o
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2013-10-31 04:52:06 +08:00
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obj-$(CONFIG_MIPS_VPE_LOADER_MT) += vpe-mt.o
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2013-01-22 19:59:30 +08:00
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obj-$(CONFIG_MIPS_VPE_APSP_API) += rtlx.o
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2014-01-01 23:29:03 +08:00
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obj-$(CONFIG_MIPS_VPE_APSP_API_CMP) += rtlx-cmp.o
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2014-01-01 23:26:46 +08:00
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obj-$(CONFIG_MIPS_VPE_APSP_API_MT) += rtlx-mt.o
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2005-07-14 23:57:16 +08:00
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2005-04-17 06:20:36 +08:00
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obj-$(CONFIG_IRQ_CPU_RM7K) += irq-rm7000.o
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2008-07-16 01:44:34 +08:00
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obj-$(CONFIG_MIPS_MSC) += irq-msc01.o
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2007-08-02 22:35:53 +08:00
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obj-$(CONFIG_IRQ_TXX9) += irq_txx9.o
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2007-09-13 22:51:26 +08:00
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obj-$(CONFIG_IRQ_GT641XX) += irq-gt641xx.o
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2005-04-17 06:20:36 +08:00
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2010-08-04 02:22:20 +08:00
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obj-$(CONFIG_KPROBES) += kprobes.o
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2005-09-04 06:56:16 +08:00
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obj-$(CONFIG_32BIT) += scall32-o32.o
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obj-$(CONFIG_64BIT) += scall64-64.o
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2007-02-15 09:53:00 +08:00
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obj-$(CONFIG_MIPS32_COMPAT) += linux32.o ptrace32.o signal32.o
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2005-04-17 06:20:36 +08:00
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obj-$(CONFIG_MIPS32_N32) += binfmt_elfn32.o scall64-n32.o signal_n32.o
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2016-06-17 23:03:45 +08:00
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obj-$(CONFIG_MIPS32_O32) += binfmt_elfo32.o scall64-o32.o signal_o32.o
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2005-04-17 06:20:36 +08:00
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2008-07-30 04:58:53 +08:00
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obj-$(CONFIG_KGDB) += kgdb.o
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2005-04-17 06:20:36 +08:00
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obj-$(CONFIG_PROC_FS) += proc.o
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2015-05-19 16:50:29 +08:00
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obj-$(CONFIG_MAGIC_SYSRQ) += sysrq.o
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2005-04-17 06:20:36 +08:00
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2005-09-04 06:56:16 +08:00
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obj-$(CONFIG_64BIT) += cpu-bugs64.o
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2005-04-17 06:20:36 +08:00
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2007-10-12 06:46:10 +08:00
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obj-$(CONFIG_I8253) += i8253.o
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2006-03-14 13:11:50 +08:00
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2008-04-04 23:55:41 +08:00
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obj-$(CONFIG_GPIO_TXX9) += gpio_txx9.o
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2016-03-31 17:05:36 +08:00
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obj-$(CONFIG_RELOCATABLE) += relocate.o
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2012-10-12 00:14:58 +08:00
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obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o crash.o
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obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
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2007-03-01 19:56:43 +08:00
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obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
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2010-02-08 19:59:39 +08:00
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obj-$(CONFIG_EARLY_PRINTK_8250) += early_printk_8250.o
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2010-02-17 07:26:35 +08:00
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obj-$(CONFIG_SPINLOCK_TEST) += spinlock_test.o
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2010-11-23 23:06:25 +08:00
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obj-$(CONFIG_MIPS_MACHINE) += mips_machine.o
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2014-12-03 23:47:03 +08:00
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obj-$(CONFIG_MIPSR2_TO_R6_EMULATOR) += mips-r2-to-r6-emul.o
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2006-10-18 21:14:55 +08:00
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2012-10-02 22:42:36 +08:00
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CFLAGS_cpu-bugs64.o = $(shell if $(CC) $(KBUILD_CFLAGS) -Wa,-mdaddi -c -o /dev/null -x c /dev/null >/dev/null 2>&1; then echo "-DHAVE_AS_SET_DADDI"; fi)
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2007-07-11 00:33:01 +08:00
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obj-$(CONFIG_HAVE_STD_PC_SERIAL_PORT) += 8250-platform.o
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2007-07-30 18:48:58 +08:00
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2011-09-24 08:29:55 +08:00
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obj-$(CONFIG_PERF_EVENTS) += perf_event.o
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obj-$(CONFIG_HW_PERF_EVENTS) += perf_event_mipsxx.o
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2010-10-12 19:37:22 +08:00
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2010-12-29 05:26:23 +08:00
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obj-$(CONFIG_JUMP_LABEL) += jump_label.o
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2015-07-30 04:44:53 +08:00
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obj-$(CONFIG_UPROBES) += uprobes.o
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2010-12-29 05:26:23 +08:00
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2014-01-15 18:31:51 +08:00
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obj-$(CONFIG_MIPS_CM) += mips-cm.o
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2014-01-15 18:31:52 +08:00
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obj-$(CONFIG_MIPS_CPC) += mips-cpc.o
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2014-01-15 18:31:51 +08:00
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2014-03-04 18:11:39 +08:00
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obj-$(CONFIG_CPU_PM) += pm.o
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2014-04-14 18:00:56 +08:00
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obj-$(CONFIG_MIPS_CPS_PM) += pm-cps.o
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2014-03-04 18:11:39 +08:00
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2013-01-04 03:01:52 +08:00
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#
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MIPS: Fix code generation for non-DSP capable CPUs
Commit 32a7ede (MIPS: dsp: Add assembler support for DSP ASEs) has
enabled the use of DSP ASE specific instructions such as rddsp and wrdsp
under the idea that all code path that will make use of these two
instructions are properly checking for cpu_has_dsp to ensure that the
particular CPU we are running on *actually* supports DSP ASE.
This commit actually causes the following oops on QEMU Malta emulating a
MIPS 24Kc without the DSP ASE implemented:
[ 7.960000] Reserved instruction in kernel
[ 7.960000] Cpu 0
[ 7.960000] $ 0 : 00000000 00000000 00000014 00000005
[ 7.960000] $ 4 : 8fc2de48 00000001 00000000 8f59ddb0
[ 7.960000] $ 8 : 8f5ceec4 00000018 00000c00 00800000
[ 7.960000] $12 : 00000100 00000200 00000000 00457b84
[ 7.960000] $16 : 00000000 8fc2ba78 8f4ec980 00000001
[ 7.960000] $20 : 80418f90 00000000 00000000 000002dd
[ 7.960000] $24 : 0000009c 7730d7b8
[ 7.960000] $28 : 8f59c000 8f59dd38 00000001 80104248
[ 7.960000] Hi : 0000001d
[ 7.960000] Lo : 0000000b
[ 7.960000] epc : 801041ec thread_saved_pc+0x2c/0x38
[ 7.960000] Not tainted
[ 7.960000] ra : 80104248 get_wchan+0x48/0xac
[ 7.960000] Status: 1000b703 KERNEL EXL IE
[ 7.960000] Cause : 10800028
[ 7.960000] PrId : 00019300 (MIPS 24Kc)
[ 7.960000] Modules linked in:
[ 7.960000] Process killall (pid: 1574, threadinfo=8f59c000,
task=8fd14558, tls=773aa440)
[ 7.960000] Stack : 8fc2ba78 8012b008 0000000c 0000001d 00000000
00000000 8f58a380
8f58a380 8fc2ba78 80202668 8f59de78 8f468600 8f59de28
801b2a3c 8f59df00 8f98ba20 74696e69
8f468600 8f59de28 801b7308 0081c007 00000000 00000000
00000000 00000000 00000000 00000000
00000000 8fc2bbb4 00000001 0000001d 0000000b 77f038cc
7fe80648 ffffffff ffffffff 00000000
00000001 0016e000 00000000 ...
[ 7.960000] Call Trace:
[ 7.960000] [<801041ec>] thread_saved_pc+0x2c/0x38
[ 7.960000] [<80104248>] get_wchan+0x48/0xac
The disassembly of thread_saved_pc points to the following:
000006d0 <thread_saved_pc>:
6d0: 8c820208 lw v0,520(a0)
6d4: 3c030000 lui v1,0x0
6d8: 24630000 addiu v1,v1,0
6dc: 10430008 beq v0,v1,700 <thread_saved_pc+0x30>
6e0: 00000000 nop
6e4: 3c020000 lui v0,0x0
6e8: 8c43000c lw v1,12(v0)
6ec: 04620004 bltzl v1,700 <thread_saved_pc+0x30>
6f0: 00001021 move v0,zero
6f4: 8c840200 lw a0,512(a0)
6f8: 00031080 sll v0,v1,0x2
6fc: 7c44100a lwx v0,a0(v0) <------------
700: 03e00008 jr ra
704: 00000000 nop
If we specifically disable -mdsp/-mdspr2 for arch/mips/kernel/process.o,
we get the following (non-crashing) assembly:
00000708 <thread_saved_pc>:
708: 8c820208 lw v0,520(a0)
70c: 3c030000 lui v1,0x0
710: 24630000 addiu v1,v1,0
714: 10430009 beq v0,v1,73c <thread_saved_pc+0x34>
718: 00000000 nop
71c: 3c020000 lui v0,0x0
720: 8c42000c lw v0,12(v0)
724: 04420005 bltzl v0,73c <thread_saved_pc+0x34>
728: 00001021 move v0,zero
72c: 8c830200 lw v1,512(a0)
730: 00021080 sll v0,v0,0x2
734: 00431021 addu v0,v0,v1
738: 8c420000 lw v0,0(v0)
73c: 03e00008 jr ra
740: 00000000 nop
The specific line that leads a different assembly being produced is:
unsigned long thread_saved_pc(struct task_struct *tsk)
...
return ((unsigned long *)t->reg29)[schedule_mfi.pc_offset]; <---
The problem here is that the compiler was given the right to use DSP
instructions with the -mdsp / -mdspr2 command-line switches and
performed some optimization for us and used DSP ASE instructions where
we are not checking that the running CPU actually supports DSP ASE.
This patch fixes the issue by partially reverting commit 32a7ede for
arch/mips/kernel/Makefile in order to remove the -mdsp / -mdspr2
compiler command-line switches such that we are now guaranteed that the
compiler will not optimize using DSP ASE reserved instructions. We also
need to fixup the rddsp/wrdsp and m{t,h}{hi,lo}{0,1,2,3} macros in
arch/mips/include/asm/mipsregs.h to tell the assembler that we are going
to explicitely use DSP ASE reserved instructions. The comment in
arch/mips/kernel/Makefile is also updated to reflect that.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: blogic@openwrt.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-03-18 23:56:10 +08:00
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# DSP ASE supported for MIPS32 or MIPS64 Release 2 cores only. It is not
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# safe to unconditionnaly use the assembler -mdsp / -mdspr2 switches
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# here because the compiler may use DSP ASE instructions (such as lwx) in
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# code paths where we cannot check that the CPU we are running on supports it.
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# Proper abstraction using HAVE_AS_DSP and macros is done in
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# arch/mips/include/asm/mipsregs.h.
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2013-01-04 03:01:52 +08:00
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#
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ifeq ($(CONFIG_CPU_MIPSR2), y)
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CFLAGS_DSP = -DHAVE_AS_DSP
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CFLAGS_signal.o = $(CFLAGS_DSP)
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CFLAGS_signal32.o = $(CFLAGS_DSP)
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CFLAGS_process.o = $(CFLAGS_DSP)
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CFLAGS_branch.o = $(CFLAGS_DSP)
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CFLAGS_ptrace.o = $(CFLAGS_DSP)
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endif
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2009-12-17 09:57:36 +08:00
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CPPFLAGS_vmlinux.lds := $(KBUILD_CFLAGS)
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