[POWERPC] Use cache-inhibited large page bit from firmware
authorPaul Mackerras <paulus@samba.org>
Wed, 3 Oct 2007 04:41:15 +0000 (14:41 +1000)
committerPaul Mackerras <paulus@samba.org>
Tue, 9 Oct 2007 11:00:48 +0000 (21:00 +1000)
Discussions with firmware architects have confirmed that the bit in
the ibm,pa-features property that indicates support for
cache-inhibited large (>= 64kB) page mappings does in fact mean that
the hypervisor allows 64kB mappings to I/O devices.

Thus we can now enable the code that tests that bit and sets our
CPU_FTR_CI_LARGE_PAGE feature bit.

Signed-off-by: Paul Mackerras <paulus@samba.org>
arch/powerpc/kernel/prom.c

index 172dcc3..9f329a8 100644 (file)
@@ -531,10 +531,7 @@ static struct ibm_pa_feature {
        {CPU_FTR_CTRL, 0,               0, 3, 0},
        {CPU_FTR_NOEXECUTE, 0,          0, 6, 0},
        {CPU_FTR_NODSISRALIGN, 0,       1, 1, 1},
-#if 0
-       /* put this back once we know how to test if firmware does 64k IO */
        {CPU_FTR_CI_LARGE_PAGE, 0,      1, 2, 0},
-#endif
        {CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
 };