[PATCH] cacheflush.2: Document Architecture-specific variants

[Alejandro Colomar <alx.manpages@gmail.com>]

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
---

Hi Michael,

Please apply this patch after
'[PATCH v5] cacheflush.2: Document __builtin___clear_cache() as a more
 portable alternative'.

Thanks,

Alex

 man2/cacheflush.2 | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/man2/cacheflush.2 b/man2/cacheflush.2
index fc35f1a0b..0761b429a 100644
--- a/man2/cacheflush.2
+++ b/man2/cacheflush.2
@@ -31,6 +31,10 @@ cacheflush \- flush contents of instruction and/or data cache
 .PP
 .BI "int cacheflush(char *" addr ", int "nbytes ", int "cache );
 .fi
+.PP
+.IR Note :
+On some architectures,
+there is no glibc wrapper for this system call; see NOTES.
 .SH DESCRIPTION
 .BR cacheflush ()
 flushes the contents of the indicated cache(s) for the
@@ -87,6 +91,44 @@ but nowadays, Linux provides a
 .BR cacheflush ()
 system call on some other architectures, but with different arguments.
 .SH NOTES
+.SS Architecture-specific variants
+Glibc provides a wrapper for this system call,
+with the prototype shown in SYNOPSIS,
+for the following architectures:
+ARC, CSKY, MIPS, and NIOS2.
+.PP
+On some other architectures,
+Linux provides this system call, with different arguments:
+.TP
+M68K:
+.PP
+.in +4n
+.EX
+.BI "int cacheflush(unsigned long " addr ", int " scope ", int " cache ,
+.BI "               unsigned long " len );
+.EE
+.in
+.TP
+SH:
+.PP
+.in +4n
+.EX
+.BI "int cacheflush(unsigned long " addr ", unsigned long " len ", int " op );
+.EE
+.in
+.TP
+NDS32:
+.PP
+.in +4n
+.EX
+.BI "int cacheflush(unsigned int " start ", unsigned int " end ", int " cache );
+.EE
+.in
+.PP
+On the above architectures,
+glibc does not provide a wrapper for this system call; call it using
+.BR syscall (2).
+.SS GCC alternative
 Unless you need the finer grained control that this system call provides,
 you probably want to use the GCC built-in function
 .BR __builtin___clear_cache (),
-- 
2.29.2