checkpatch: add some common Blackfin checks

Add checks for Blackfin-specific issues that seem to crop up from time to
time.  In particular, we have helper macros to break a 32bit address into
the hi/lo parts, and we want to make sure people use the csync/ssync
variant that includes fun anomaly workarounds.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -1378,6 +1378,18 @@ sub process {
 			WARN("adding a line without newline at end of file\n" . $herecurr);
 		}
 
+# Blackfin: use hi/lo macros
+		if ($realfile =~ m@arch/blackfin/.*\.S$@) {
+			if ($line =~ /\.[lL][[:space:]]*=.*&[[:space:]]*0x[fF][fF][fF][fF]/) {
+				my $herevet = "$here\n" . cat_vet($line) . "\n";
+				ERROR("use the LO() macro, not (... & 0xFFFF)\n" . $herevet);
+			}
+			if ($line =~ /\.[hH][[:space:]]*=.*>>[[:space:]]*16/) {
+				my $herevet = "$here\n" . cat_vet($line) . "\n";
+				ERROR("use the HI() macro, not (... >> 16)\n" . $herevet);
+			}
+		}
+
 # check we are in a valid source file C or perl if not then ignore this hunk
 		next if ($realfile !~ /\.(h|c|pl)$/);
 
@@ -1397,6 +1409,16 @@ sub process {
 			WARN("CVS style keyword markers, these will _not_ be updated\n". $herecurr);
 		}
 
+# Blackfin: don't use __builtin_bfin_[cs]sync
+		if ($line =~ /__builtin_bfin_csync/) {
+			my $herevet = "$here\n" . cat_vet($line) . "\n";
+			ERROR("use the CSYNC() macro in asm/blackfin.h\n" . $herevet);
+		}
+		if ($line =~ /__builtin_bfin_ssync/) {
+			my $herevet = "$here\n" . cat_vet($line) . "\n";
+			ERROR("use the SSYNC() macro in asm/blackfin.h\n" . $herevet);
+		}
+
 # Check for potential 'bare' types
 		my ($stat, $cond, $line_nr_next, $remain_next, $off_next);
 		if ($realcnt && $line =~ /.\s*\S/) {