[PATCH 1/2] Add missing header for musl compatibility

[Gwenhael Goavec-Merou]

From: Gwenhael Goavec-Merou

According to :
http://autobuild.buildroot.net/results/3de/3de936d9be79e151e66af15193084d82a...

linux/ioctl.h header must be included in linux_spi.c to obtain missing _IOC_SIZEBITS.

Patch based on :
http://git.buildroot.net/buildroot/commit/package/c-periphery/0001-Add-missi...

Signed-off-by: Gwenhael Goavec-Merou 
---
 linux_spi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/linux_spi.c b/linux_spi.c
index 26725e1..8d72420 100644
--- a/linux_spi.c
+++ b/linux_spi.c
@@ -28,6 +28,7 @@
 #include <unistd.h>
 #include <linux/types.h>
 #include <linux/spi/spidev.h>
+#include <linux/ioctl.h>
 #include <sys/ioctl.h>
 #include "flash.h"
 #include "chipdrivers.h"

[PATCH 2/2] fix compiling with non glibc libcs

[Gwenhael Goavec-Merou]

From: Gwenhael Goavec-Merou

When musl is used to provides libc flashrom built fail with :
[...]
rayer_spi.c:(.text+0x95): undefined reference to `outb'
[...]
satamv.c:(.text+0x5e): undefined reference to `outl'
satamv.c:(.text+0x7b): undefined reference to `outb'
collect2: error: ld returned 1 exit status

This patch changed test on __GLIBC__ by __linux__ to obtain a more generic
verification.

Patch based on :
http://git.buildroot.net/buildroot/commit/package/exfat-utils/0001-fix-compi...

Signed-off-by: Gwenhael Goavec-Merou 
---
 hwaccess.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hwaccess.h b/hwaccess.h
index 3e46192..cf27577 100644
--- a/hwaccess.h
+++ b/hwaccess.h
@@ -27,7 +27,7 @@
 #include "platform.h"

#if IS_X86
-#if defined(__GLIBC__)
+#if defined(__linux__)
 #include <sys/io.h>
 #endif
 #endif

[Stefan Tauner]

On Wed, 14 Oct 2015 10:43:07 +0200
Gwenhael Goavec-Merou  wrote:
> From: Gwenhael Goavec-Merou
>
> According to :
> http://autobuild.buildroot.net/results/3de/3de936d9be79e151e66af15193084d82a...
>
> linux/ioctl.h header must be included in linux_spi.c to obtain missing _IOC_SIZEBITS.
>
> Patch based on :
> http://git.buildroot.net/buildroot/commit/package/c-periphery/0001-Add-missi...
>
> Signed-off-by: Gwenhael Goavec-Merou

Hi Gwenhael,

I don't see how this is related to flashrom. It seems to be a patch
against c-periphery. Did you notice any compile problems of flashrom
itself?

[gwenhael.goavec]

Hi Stefan
On Mon, 26 Oct 2015 23:59:38 +0100
Stefan Tauner  wrote:
> On Wed, 14 Oct 2015 10:43:07 +0200
> Gwenhael Goavec-Merou  wrote:
> > From: Gwenhael Goavec-Merou

The compile problem is shown in this build report :
> > http://autobuild.buildroot.net/results/3de/3de936d9be79e151e66af15193084d82a...

This problem is clearly related to flashrom.
> > linux/ioctl.h header must be included in linux_spi.c to obtain
> > missing _IOC_SIZEBITS.

This patch is not my patch but one that I was inspired to do mine :
> > Patch based on :
> > http://git.buildroot.net/buildroot/commit/package/c-periphery/0001-Add-missi...
> >
> > Signed-off-by: Gwenhael Goavec-Merou
>
> Hi Gwenhael,
>
> I don't see how this is related to flashrom. It seems to be a patch
> against c-periphery. Did you notice any compile problems of flashrom
> itself?
> -- 
> Kind regards/Mit freundlichen Grüßen, Stefan Tauner

My patch to fix compile issue is on the missing part of this mail (on
the bottom of http://patchwork.coreboot.org/patch/4327/).

regards,
Gwenhael

[Stefan Tauner]

On Tue, 27 Oct 2015 08:12:24 +0100
"gwenhael.goavec"  wrote:
> Hi Stefan
> On Mon, 26 Oct 2015 23:59:38 +0100
> Stefan Tauner  wrote:
> > On Wed, 14 Oct 2015 10:43:07 +0200
> > Gwenhael Goavec-Merou  wrote:
> > > From: Gwenhael Goavec-Merou
>
> The compile problem is shown in this build report :
> > > http://autobuild.buildroot.net/results/3de/3de936d9be79e151e66af15193084d82a...
>
> This problem is clearly related to flashrom.

Well, yes true... however, I am not sure if that's actually a problem
with the includes in flashrom or the actual headers they are using.
After all we do not use the undefined macro directly, so it should be
brought in by the header file that uses it IMHO.

flashrom does not support non-glibc C libraries yet anyway (this also
affects your other patch) so this needs more investigation in any case.
I am currently building a musl "crosscompiler" toolchain on our flashrom
buildbot to allow for that (because the musl-gcc wrapper does not work
with libraries like libpci). Don't expect any results soon but I'll put
it on my todo list... thanks for the heads-up.

[Stefan Tauner]

On Wed, 14 Oct 2015 10:43:07 +0200
Gwenhael Goavec-Merou  wrote:
> From: Gwenhael Goavec-Merou
>
> According to :
> http://autobuild.buildroot.net/results/3de/3de936d9be79e151e66af15193084d82a...
>
> linux/ioctl.h header must be included in linux_spi.c to obtain missing _IOC_SIZEBITS.
>
> Patch based on :
> http://git.buildroot.net/buildroot/commit/package/c-periphery/0001-Add-missi...

This is actually a bug in the linux headers that apparently is hidden
by the glibc headers because they include the right headers "by
accident":

glibc headers corresponding to Linux 3.2.0:
# 23 "sys/ioctl.h" 2
# 24 "/usr/include/x86_64-linux-gnu/bits/ioctls.h" 3 4
# 1 "/usr/include/x86_64-linux-gnu/asm/ioctls.h" 1 3 4
# 1 "/usr/include/asm-generic/ioctls.h" 1 3 4
# 1 "/usr/include/linux/ioctl.h" 1 3 4
# 1 "/usr/include/x86_64-linux-gnu/asm/ioctl.h" 1 3 4
# 1 "/usr/include/asm-generic/ioctl.h" 1 3 4
> _IOC_SIZEBITS

(found out with the help of gcc -E -dD and some grep foo)

With musl's 1.0.5 (stable) headers sys/ioctl.h does not include any
OS-specific headers (I think) and thus no _IOC_SIZEBITS. That makes it
fail to compile flashrom's linux_spi.c as indicated in the log.

Why is that a bug in the kernel headers? Because linux/spi/spidev.h
defines a macro named SPI_MSGSIZE (that flashrom uses) that relies on
another macro (_IOC_SIZEBITS)from asm-generic/ioctl.h that should be
(indirectly) brought in by spidev.h.

Does it matter? No, we have to support it anyway hence I will include
the proposed change (if no regression crops up). Still, I would like
this to be reported "upstream". Could you please do that Gwenhael?

[PATCH] Add (implicit) support for musl libc.

[Stefan Tauner]

From: Gwenhael Goavec-Merou

This is mostly achieved by fixing or refining the inclusion of header
files and replacing glibc-specific ifdefs with more generic ones.

- <sys/io.h>: Linux-specific and not only available in glibc. Include it
               if we are running Linux and not only if glibc is active.
 - <sys/fcntl.h>: should be (and is) replaced by <fcntl.h> (without the
    			  "sys" prefix).
 - <linux/spi/spidev.h>: Does not include all necessary headers, namely
                         _IOC_SIZEBITS that is used in the definition of
                         SPI_MSGSIZE is not brought in via <linux/ioctl.h>
                         but instead we relied so far on glibc's including
                         it via <sys/ioctl.h>. Change that to explicitly
                         including <linux/ioctl.h>.
 - <endian.h>: Would also be available in musl but there is no easy way
               to detect it so we do not try yet.

The bug report and initial patches were
Signed-off-by: Gwenhael Goavec-Merou

Signed-off-by: Stefan Tauner 
---

No regressions detected on the buildbot... flashrom can be built completely
(with libpci, libusb and libftdi programmers) with musl after applying this.

hwaccess.h  | 3 ++-
 linux_spi.c | 5 +++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/hwaccess.h b/hwaccess.h
index 3e46192..25b1456 100644
--- a/hwaccess.h
+++ b/hwaccess.h
@@ -27,7 +27,7 @@
 #include "platform.h"

#if IS_X86
-#if defined(__GLIBC__)
+#if defined(__linux__)
 #include <sys/io.h>
 #endif
 #endif
@@ -115,6 +115,7 @@
 #if !defined (__FLASHROM_BIG_ENDIAN__) && !defined (__FLASHROM_LITTLE_ENDIAN__)

/* Nonstandard libc-specific macros for determining endianness. */
+/* musl provides an endian.h as well... but it can not be detected from within C. */
 #if defined(__GLIBC__)
 #include <endian.h>
 #if BYTE_ORDER == LITTLE_ENDIAN
diff --git a/linux_spi.c b/linux_spi.c
index 26725e1..19b4965 100644
--- a/linux_spi.c
+++ b/linux_spi.c
@@ -22,13 +22,14 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
-#include <sys/fcntl.h>
+#include <fcntl.h>
 #include <errno.h>
 #include <ctype.h>
 #include <unistd.h>
+#include <sys/ioctl.h>
 #include <linux/types.h>
 #include <linux/spi/spidev.h>
-#include <sys/ioctl.h>
+#include <linux/ioctl.h>
 #include "flash.h"
 #include "chipdrivers.h"
 #include "programmer.h"