powerpc: 32BIT vs. 64BIT (PPC32 vs. PPC64)

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?


Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):

x86: i386 for 32 bit, x86_64 for 64 bit
sh: sh for 32 bit, sh64 for 64 bit
sparc: sparc32 for 32 bit, sparc64 for 64 bit


thanks,
-- 
~Randy

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...

x86: i386 for 32 bit, x86_64 for 64 bit
sh: sh for 32 bit, sh64 for 64 bit
sparc: sparc32 for 32 bit, sparc64 for 64 bit

On 07/06/2018 06:45 PM, Benjamin Herrenschmidt wrote:

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?

Yes.

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.

quoted

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...

Yes, your summary is mostly correct.

I'm just looking for a way to do cross-compile builds that are close to
ppc32 allmodconfig and ppc64 allmodconfig.

quoted

x86: i386 for 32 bit, x86_64 for 64 bit
sh: sh for 32 bit, sh64 for 64 bit
sparc: sparc32 for 32 bit, sparc64 for 64 bit

I saw the powerpc merge-config targets after I sent this original email.
I can do my own homebrew that I prefer over those, though.


thanks,
-- 
~Randy

On Fri, 6 Jul 2018 21:58:29 -0700
Randy Dunlap [off-list ref] wrote:

On 07/06/2018 06:45 PM, Benjamin Herrenschmidt wrote:

quoted

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:  

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?  

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?  

Yes.

quoted

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.
  

quoted

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):  

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...  

Yes, your summary is mostly correct.

I'm just looking for a way to do cross-compile builds that are close to
ppc32 allmodconfig and ppc64 allmodconfig.

Would there a problem with adding ARCH=ppc32 / ppc64 matching? This
seems to work...

Thanks,
Nick

---
 Makefile                               | 8 ++++++++
 arch/powerpc/Kconfig                   | 9 +++++++++
 arch/powerpc/platforms/Kconfig.cputype | 8 --------
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/Makefile b/Makefile
index c5ce55cbc543..f97204aed17a 100644
--- a/Makefile
+++ b/Makefile

@@ -345,6 +345,14 @@ ifeq ($(ARCH),sh64)
        SRCARCH := sh
 endif
 
+# Additional ARCH settings for powerpc
+ifeq ($(ARCH),ppc32)
+       SRCARCH := powerpc
+endif
+ifeq ($(ARCH),ppc64)
+       SRCARCH := powerpc
+endif
+
 KCONFIG_CONFIG	?= .config
 export KCONFIG_CONFIG
 

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 9f2b75fe2c2d..3405b1b122be 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig

@@ -1,4 +1,13 @@
 # SPDX-License-Identifier: GPL-2.0
+
+config PPC64
+	bool "64-bit kernel" if "$(ARCH)" = "powerpc"
+	default "$(ARCH)" != "ppc32"
+	select ZLIB_DEFLATE
+	help
+	  This option selects whether a 32-bit or a 64-bit kernel
+	  will be built.
+
 source "arch/powerpc/platforms/Kconfig.cputype"
 
 config PPC32

diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index e6a1de521319..f6e5d6ef9782 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype

@@ -1,12 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
-config PPC64
-	bool "64-bit kernel"
-	default n
-	select ZLIB_DEFLATE
-	help
-	  This option selects whether a 32-bit or a 64-bit kernel
-	  will be built.
-
 menu "Processor support"
 choice
 	prompt "Processor Type"

-- 
2.17.0

On 07/07/2018 05:13 AM, Nicholas Piggin wrote:

On Fri, 6 Jul 2018 21:58:29 -0700
Randy Dunlap [off-list ref] wrote:

quoted

On 07/06/2018 06:45 PM, Benjamin Herrenschmidt wrote:

quoted

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:  

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?  

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?  

Yes.

quoted

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.
  

quoted

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):  

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...  

Yes, your summary is mostly correct.

I'm just looking for a way to do cross-compile builds that are close to
ppc32 allmodconfig and ppc64 allmodconfig.

Would there a problem with adding ARCH=ppc32 / ppc64 matching? This
seems to work...

Thanks,
Nick

Yes, this mostly works and is similar to a patch (my patch) on my test machine.
And they both work for allmodconfig, which is my primary build target.

And they both have one little quirk that is confusing when the build target
is defconfig:

When ARCH=ppc32, the terminal output (stdout) is: (using O=PPC32)

make[1]: Entering directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'
  GEN     ./Makefile
*** Default configuration is based on 'ppc64_defconfig'   <<<<< NOTE <<<<<
#
# configuration written to .config
#
make[1]: Leaving directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'


I expect that can be fixed also.  :)

And the written .config file is indeed for 32BIT, not 64BIT.

Thanks, Nick.

-- 
~Randy

Randy Dunlap [off-list ref] writes:

Hi,

Is there a good way (or a shortcut) to do something like:

The best I know of is:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

$ echo CONFIG_PPC64=n > allmod.config
$ KCONFIG_ALLCONFIG=1 make allmodconfig
$ grep PPC32 .config
CONFIG_PPC32=y

Which is still a bit clunky.


I looked at this a while back and the problem we have is that the 32-bit
kernel is not a single thing. There are multiple 32-bit platforms which
are mutually exclusive.

eg, from menuconfig:

 - 512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx
 - Freescale 85xx
 - Freescale 8xx
 - AMCC 40x
 - AMCC 44x, 46x or 47x
 - Freescale e200


So we could have a 32-bit allmodconfig, but we'd need to chose one of
the above, and we'd still only be testing some of the code.

Having said that you're the 2nd person to ask about this, so we should
clearly do something to make a 32-bit allmodconfig easier, even if it's
not perfect.

cheers

On Sat, 7 Jul 2018 07:59:49 -0700
Randy Dunlap [off-list ref] wrote:

On 07/07/2018 05:13 AM, Nicholas Piggin wrote:

quoted

On Fri, 6 Jul 2018 21:58:29 -0700
Randy Dunlap [off-list ref] wrote:
  

quoted

On 07/06/2018 06:45 PM, Benjamin Herrenschmidt wrote:  

quoted

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:    

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?    

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?    

Yes.
 

quoted

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.
    

quoted

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):    

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...    

Yes, your summary is mostly correct.

I'm just looking for a way to do cross-compile builds that are close to
ppc32 allmodconfig and ppc64 allmodconfig.  

Would there a problem with adding ARCH=ppc32 / ppc64 matching? This
seems to work...

Thanks,
Nick  

Yes, this mostly works and is similar to a patch (my patch) on my test machine.
And they both work for allmodconfig, which is my primary build target.

And they both have one little quirk that is confusing when the build target
is defconfig:

When ARCH=ppc32, the terminal output (stdout) is: (using O=PPC32)

make[1]: Entering directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'
  GEN     ./Makefile
*** Default configuration is based on 'ppc64_defconfig'   <<<<< NOTE <<<<<
#
# configuration written to .config
#
make[1]: Leaving directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'


I expect that can be fixed also.  :)

It can, we'd just have to choose one of the many 32-bit configs to be
the default config in that case. I don't know much about 32 bit ppc,
so I don't know what would be the most useful for allmodconfig type of
build tests.

Even 64 bit have a bunch of major variants that are exclusive at build
time (Server vs embedded, endian, etc). So maybe the simple ppc64/ppc32
is not enough. Not sure.

Thanks,
Nick

On 07/08/2018 04:51 AM, Michael Ellerman wrote:

Randy Dunlap [off-list ref] writes:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

The best I know of is:

quoted

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

$ echo CONFIG_PPC64=n > allmod.config
$ KCONFIG_ALLCONFIG=1 make allmodconfig
$ grep PPC32 .config
CONFIG_PPC32=y

Which is still a bit clunky.

That's close to what I already do.  And it's very script-able.

I looked at this a while back and the problem we have is that the 32-bit
kernel is not a single thing. There are multiple 32-bit platforms which
are mutually exclusive.

eg, from menuconfig:

 - 512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx
 - Freescale 85xx
 - Freescale 8xx
 - AMCC 40x
 - AMCC 44x, 46x or 47x
 - Freescale e200


So we could have a 32-bit allmodconfig, but we'd need to chose one of
the above, and we'd still only be testing some of the code.

Having said that you're the 2nd person to ask about this, so we should
clearly do something to make a 32-bit allmodconfig easier, even if it's
not perfect.

Thanks.

-- 
~Randy

Nicholas Piggin [off-list ref] writes:

On Fri, 6 Jul 2018 21:58:29 -0700
Randy Dunlap [off-list ref] wrote:

quoted

On 07/06/2018 06:45 PM, Benjamin Herrenschmidt wrote:

quoted

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:  

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?  

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?  

Yes.

quoted

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.
  

quoted

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):  

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...  

Yes, your summary is mostly correct.

I'm just looking for a way to do cross-compile builds that are close to
ppc32 allmodconfig and ppc64 allmodconfig.

Would there a problem with adding ARCH=ppc32 / ppc64 matching? This
seems to work...

It's a cute trick but I'd rather avoid it.

It overloads ARCH which can be confusing to people and tools. For
example I'd have to special case it in kisskb.

I think we can achieve a similar result by having more PHONY defconfig
targets.

eg, we can do ppc32_allmodconfig like below. And if there's interest we
could do a 4xx_allmodconfig etc.

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 2ea575cb3401..2556c2182789 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile

@@ -354,6 +354,11 @@ mpc86xx_smp_defconfig:
 	$(call merge_into_defconfig,mpc86xx_basic_defconfig,\
 		86xx-smp 86xx-hw fsl-emb-nonhw)
 
+PHONY += ppc32_allmodconfig
+ppc32_allmodconfig:
+	$(Q)$(MAKE) KCONFIG_ALLCONFIG=$(srctree)/arch/powerpc/configs/book3s_32.config \
+		-f $(srctree)/Makefile allmodconfig
+
 define archhelp
   @echo '* zImage          - Build default images selected by kernel config'
   @echo '  zImage.*        - Compressed kernel image (arch/$(ARCH)/boot/zImage.*)'

diff --git a/arch/powerpc/configs/book3s_32.config b/arch/powerpc/configs/book3s_32.config
new file mode 100644
index 000000000000..8721eb7b1294
--- /dev/null
+++ b/arch/powerpc/configs/book3s_32.config

@@ -0,0 +1,2 @@
+CONFIG_PPC64=n
+CONFIG_PPC_BOOK3S_32=y

cheers

On Sun, Jul 8, 2018 at 1:53 PM Michael Ellerman [off-list ref] wrote:

Randy Dunlap [off-list ref] writes:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

The best I know of is:

quoted

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

$ echo CONFIG_PPC64=n > allmod.config
$ KCONFIG_ALLCONFIG=1 make allmodconfig
$ grep PPC32 .config
CONFIG_PPC32=y

Which is still a bit clunky.


I looked at this a while back and the problem we have is that the 32-bit
kernel is not a single thing. There are multiple 32-bit platforms which
are mutually exclusive.

eg, from menuconfig:

 - 512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx
 - Freescale 85xx
 - Freescale 8xx
 - AMCC 40x
 - AMCC 44x, 46x or 47x
 - Freescale e200

Most Linux distro seems to have drop support for ppc32. So I'd suggest
to pick Debian powperc default config (but I agree that I am a little
biased here).

So we could have a 32-bit allmodconfig, but we'd need to chose one of
the above, and we'd still only be testing some of the code.

Having said that you're the 2nd person to ask about this, so we should
clearly do something to make a 32-bit allmodconfig easier, even if it's
not perfect.

cheers

Randy,

On Mon, Jul 9, 2018 at 2:00 PM Mathieu Malaterre [off-list ref] wrote:

On Sun, Jul 8, 2018 at 1:53 PM Michael Ellerman [off-list ref] wrote:

quoted

Randy Dunlap [off-list ref] writes:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

The best I know of is:

quoted

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

$ echo CONFIG_PPC64=n > allmod.config
$ KCONFIG_ALLCONFIG=1 make allmodconfig
$ grep PPC32 .config
CONFIG_PPC32=y

Which is still a bit clunky.


I looked at this a while back and the problem we have is that the 32-bit
kernel is not a single thing. There are multiple 32-bit platforms which
are mutually exclusive.

eg, from menuconfig:

 - 512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx
 - Freescale 85xx
 - Freescale 8xx
 - AMCC 40x
 - AMCC 44x, 46x or 47x
 - Freescale e200

Most Linux distro seems to have drop support for ppc32. So I'd suggest
to pick Debian powperc default config (but I agree that I am a little
biased here).

I tried an allmode as suggest by Michael (above). But I get a build error:

  MODPOST vmlinux.o
drivers/android/binder.o: In function `binder_thread_write':
binder.c:(.text+0xc750): undefined reference to `__get_user_bad'
binder.c:(.text+0xc76c): undefined reference to `__get_user_bad'
binder.c:(.text+0xc790): undefined reference to `__get_user_bad'
binder.c:(.text+0xc7d4): undefined reference to `__get_user_bad'
binder.c:(.text+0xc7f4): undefined reference to `__get_user_bad'


So for now I need to do: CONFIG_ANDROID_BINDER_IPC=n

How did you get passed this build failure ?

quoted

So we could have a 32-bit allmodconfig, but we'd need to chose one of
the above, and we'd still only be testing some of the code.

Having said that you're the 2nd person to ask about this, so we should
clearly do something to make a 32-bit allmodconfig easier, even if it's
not perfect.

cheers

On 07/13/2018 04:41 AM, Mathieu Malaterre wrote:

Randy,

On Mon, Jul 9, 2018 at 2:00 PM Mathieu Malaterre [off-list ref] wrote:

quoted

On Sun, Jul 8, 2018 at 1:53 PM Michael Ellerman [off-list ref] wrote:

quoted

Randy Dunlap [off-list ref] writes:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

The best I know of is:

quoted

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

$ echo CONFIG_PPC64=n > allmod.config
$ KCONFIG_ALLCONFIG=1 make allmodconfig
$ grep PPC32 .config
CONFIG_PPC32=y

Which is still a bit clunky.


I looked at this a while back and the problem we have is that the 32-bit
kernel is not a single thing. There are multiple 32-bit platforms which
are mutually exclusive.

eg, from menuconfig:

 - 512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx
 - Freescale 85xx
 - Freescale 8xx
 - AMCC 40x
 - AMCC 44x, 46x or 47x
 - Freescale e200

Most Linux distro seems to have drop support for ppc32. So I'd suggest
to pick Debian powperc default config (but I agree that I am a little
biased here).

I tried an allmode as suggest by Michael (above). But I get a build error:

  MODPOST vmlinux.o
drivers/android/binder.o: In function `binder_thread_write':
binder.c:(.text+0xc750): undefined reference to `__get_user_bad'
binder.c:(.text+0xc76c): undefined reference to `__get_user_bad'
binder.c:(.text+0xc790): undefined reference to `__get_user_bad'
binder.c:(.text+0xc7d4): undefined reference to `__get_user_bad'
binder.c:(.text+0xc7f4): undefined reference to `__get_user_bad'


So for now I need to do: CONFIG_ANDROID_BINDER_IPC=n

How did you get passed this build failure ?

Hi,

I am not seeing an error on that driver build.

I am using gcc 8.1.0 from kernel.org:
https://mirrors.edge.kernel.org/pub/tools/crosstool/

and building on x86_64.


-- 
~Randy

On 07/13/2018 04:24 PM, Randy Dunlap wrote:

On 07/13/2018 04:41 AM, Mathieu Malaterre wrote:

quoted

Randy,

On Mon, Jul 9, 2018 at 2:00 PM Mathieu Malaterre [off-list ref] wrote:

quoted

On Sun, Jul 8, 2018 at 1:53 PM Michael Ellerman [off-list ref] wrote:

quoted

Randy Dunlap [off-list ref] writes:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

The best I know of is:

quoted

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

$ echo CONFIG_PPC64=n > allmod.config
$ KCONFIG_ALLCONFIG=1 make allmodconfig
$ grep PPC32 .config
CONFIG_PPC32=y

Which is still a bit clunky.


I looked at this a while back and the problem we have is that the 32-bit
kernel is not a single thing. There are multiple 32-bit platforms which
are mutually exclusive.

eg, from menuconfig:

 - 512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx
 - Freescale 85xx
 - Freescale 8xx
 - AMCC 40x
 - AMCC 44x, 46x or 47x
 - Freescale e200

Most Linux distro seems to have drop support for ppc32. So I'd suggest
to pick Debian powperc default config (but I agree that I am a little
biased here).

I tried an allmode as suggest by Michael (above). But I get a build error:

  MODPOST vmlinux.o
drivers/android/binder.o: In function `binder_thread_write':
binder.c:(.text+0xc750): undefined reference to `__get_user_bad'
binder.c:(.text+0xc76c): undefined reference to `__get_user_bad'
binder.c:(.text+0xc790): undefined reference to `__get_user_bad'
binder.c:(.text+0xc7d4): undefined reference to `__get_user_bad'
binder.c:(.text+0xc7f4): undefined reference to `__get_user_bad'


So for now I need to do: CONFIG_ANDROID_BINDER_IPC=n

How did you get passed this build failure ?

Hi,

I am not seeing an error on that driver build.

I am using gcc 8.1.0 from kernel.org:
https://mirrors.edge.kernel.org/pub/tools/crosstool/

and building on x86_64.

Hi Mathieu,

I do see this build error (slightly different undefined reference though)
when I do an arch/microblaze/ cross-build:

drivers/android/binder.o: In function `binder_thread_write':
drivers/android/.tmp_gl_binder.o:(.text+0xcba8): undefined reference to `__user_bad'
drivers/android/.tmp_gl_binder.o:(.text+0xcbd4): undefined reference to `__user_bad'
drivers/android/.tmp_gl_binder.o:(.text+0xcfbc): undefined reference to `__user_bad'
drivers/android/.tmp_gl_binder.o:(.text+0xd648): undefined reference to `__user_bad'
drivers/android/.tmp_gl_binder.o:(.text+0xdbc0): undefined reference to `__user_bad'


-- 
~Randy

2018-07-07 23:59 GMT+09:00 Randy Dunlap [off-list ref]:

On 07/07/2018 05:13 AM, Nicholas Piggin wrote:

quoted

On Fri, 6 Jul 2018 21:58:29 -0700
Randy Dunlap [off-list ref] wrote:

quoted

On 07/06/2018 06:45 PM, Benjamin Herrenschmidt wrote:

quoted

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?

Yes.

quoted

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.

quoted

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...

Yes, your summary is mostly correct.

I'm just looking for a way to do cross-compile builds that are close to
ppc32 allmodconfig and ppc64 allmodconfig.

Would there a problem with adding ARCH=ppc32 / ppc64 matching? This
seems to work...

Thanks,
Nick

Yes, this mostly works and is similar to a patch (my patch) on my test machine.
And they both work for allmodconfig, which is my primary build target.

And they both have one little quirk that is confusing when the build target
is defconfig:

When ARCH=ppc32, the terminal output (stdout) is: (using O=PPC32)

make[1]: Entering directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'
  GEN     ./Makefile
*** Default configuration is based on 'ppc64_defconfig'   <<<<< NOTE <<<<<
#
# configuration written to .config
#
make[1]: Leaving directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'

Maybe, we can set one of ppc32 defconfigs to KBUILD_DEFCONFIG
if ARCH is ppc32 ?


ifeq ($(ARCH),ppc32)
   KBUILD_DEFCONFIG := (some reasonable 32bit machine _defconfig)
else
   KBUILD_DEFCONFIG := ppc64_defconfig
endif

ifeq ($(CROSS_COMPILE),)
    KBUILD_DEFCONFIG := $(shell uname -m)_defconfig
endif

I expect that can be fixed also.  :)

And the written .config file is indeed for 32BIT, not 64BIT.

Thanks, Nick.

quoted

---
 Makefile                               | 8 ++++++++
 arch/powerpc/Kconfig                   | 9 +++++++++
 arch/powerpc/platforms/Kconfig.cputype | 8 --------
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/Makefile b/Makefile
index c5ce55cbc543..f97204aed17a 100644
--- a/Makefile
+++ b/Makefile

@@ -345,6 +345,14 @@ ifeq ($(ARCH),sh64)
        SRCARCH := sh
 endif

+# Additional ARCH settings for powerpc
+ifeq ($(ARCH),ppc32)
+       SRCARCH := powerpc
+endif
+ifeq ($(ARCH),ppc64)
+       SRCARCH := powerpc
+endif
+
 KCONFIG_CONFIG       ?= .config
 export KCONFIG_CONFIG

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 9f2b75fe2c2d..3405b1b122be 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig

@@ -1,4 +1,13 @@
 # SPDX-License-Identifier: GPL-2.0
+
+config PPC64
+     bool "64-bit kernel" if "$(ARCH)" = "powerpc"
+     default "$(ARCH)" != "ppc32"
+     select ZLIB_DEFLATE
+     help
+       This option selects whether a 32-bit or a 64-bit kernel
+       will be built.
+
 source "arch/powerpc/platforms/Kconfig.cputype"

 config PPC32

diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index e6a1de521319..f6e5d6ef9782 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype

@@ -1,12 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
-config PPC64
-     bool "64-bit kernel"
-     default n
-     select ZLIB_DEFLATE
-     help
-       This option selects whether a 32-bit or a 64-bit kernel
-       will be built.
-
 menu "Processor support"
 choice
      prompt "Processor Type"

--
~Randy
--
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-- 
Best Regards
Masahiro Yamada

Masahiro Yamada [off-list ref] writes:

2018-07-07 23:59 GMT+09:00 Randy Dunlap [off-list ref]:

quoted

On 07/07/2018 05:13 AM, Nicholas Piggin wrote:

quoted

On Fri, 6 Jul 2018 21:58:29 -0700
Randy Dunlap [off-list ref] wrote:

quoted

On 07/06/2018 06:45 PM, Benjamin Herrenschmidt wrote:

quoted

On Thu, 2018-07-05 at 14:30 -0700, Randy Dunlap wrote:

quoted

Hi,

Is there a good way (or a shortcut) to do something like:

$ make ARCH=powerpc O=PPC32 [other_options] allmodconfig
  to get a PPC32/32BIT allmodconfig

and also be able to do:

$make ARCH=powerpc O=PPC64 [other_options] allmodconfig
  to get a PPC64/64BIT allmodconfig?

Hrm... O= is for the separate build dir, so there much be something
else.

You mean having ARCH= aliases like ppc/ppc32 and ppc64 ?

Yes.

quoted

That would be a matter of overriding some .config defaults I suppose, I
don't know how this is done on other archs.

I see the aliasing trick in the Makefile but that's about it.

quoted

Note that arch/x86, arch/sh, and arch/sparc have ways to do
some flavor(s) of this (from Documentation/kbuild/kbuild.txt;
sh and sparc based on a recent "fix" patch from me):

I fail to see what you are actually talking about here ... sorry. Do
you have concrete examples on x86 or sparc ? From what I can tell the
"i386" or "sparc32/sparc64" aliases just change SRCARCH in Makefile and
32 vs 64-bit is just a Kconfig option...

Yes, your summary is mostly correct.

I'm just looking for a way to do cross-compile builds that are close to
ppc32 allmodconfig and ppc64 allmodconfig.

Would there a problem with adding ARCH=ppc32 / ppc64 matching? This
seems to work...

Yes, this mostly works and is similar to a patch (my patch) on my test machine.
And they both work for allmodconfig, which is my primary build target.

And they both have one little quirk that is confusing when the build target
is defconfig:

When ARCH=ppc32, the terminal output (stdout) is: (using O=PPC32)

make[1]: Entering directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'
  GEN     ./Makefile
*** Default configuration is based on 'ppc64_defconfig'   <<<<< NOTE <<<<<
#
# configuration written to .config
#
make[1]: Leaving directory '/home/rdunlap/lnx/lnx-418-rc3/PPC32'

Maybe, we can set one of ppc32 defconfigs to KBUILD_DEFCONFIG
if ARCH is ppc32 ?

We could, but as I said in another reply I'd rather we didn't play
tricks with ARCH.

I've merged a patch to add three new allmodconfig targets for ppc32,
ppc64le and ppc64_book3e:

  https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=54457&state=*


cheers