[PATCH] M68k 68060 errata I14

M68k: gcc lately manages to generate the code sequence described in the 060
errata I14, so use the described workaround (from Roman Zippel)

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/m68k/kernel/setup.c b/arch/m68k/kernel/setup.c
index 7680eabc3337..1d2563e115e4 100644
--- a/arch/m68k/kernel/setup.c
+++ b/arch/m68k/kernel/setup.c
@@ -237,6 +237,18 @@ void __init setup_arch(char **cmdline_p)
 	}
 #endif
 
+	if (CPU_IS_060) {
+		u32 pcr;
+
+		asm (".chip 68060; movec %%pcr,%0; .chip 68k"
+		     : "=d" (pcr));
+		if (((pcr >> 8) & 0xff) <= 5) {
+			printk("Enabling workaround for errata I14\n");
+			asm (".chip 68060; movec %0,%%pcr; .chip 68k"
+			     : : "d" (pcr | 0x20));
+		}
+	}
+
 	init_mm.start_code = PAGE_OFFSET;
 	init_mm.end_code = (unsigned long) &_etext;
 	init_mm.end_data = (unsigned long) &_edata;