sparc32: Add back early sun4/sun4c detection so we can warn properly.

We need to do the check before we try to remap the kernel using
SRMMU operations.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 0 deletions

diff --git a/arch/sparc/kernel/head_32.S b/arch/sparc/kernel/head_32.S
index ea45894db0bd..0d01798bb120 100644
--- a/arch/sparc/kernel/head_32.S
+++ b/arch/sparc/kernel/head_32.S
@@ -532,6 +532,29 @@ copy_prom_done:
                 be      go_to_highmem           ! this will be a nop then
                  nop
 
+                /* Validate that we are in fact running on an
+                 * SRMMU based cpu.
+                 */
+                set     0x4000, %g6
+                cmp     %g7, %g6
+                bne     not_a_sun4
+                 nop
+
+halt_sun4_or_sun4c:
+                ld      [%g7 + 0x68], %o1
+                set     sun4c_notsup, %o0
+                sub     %o0, %l6, %o0
+                call    %o1
+                 nop
+                ba      halt_me
+                 nop
+
+not_a_sun4:
+                lda     [%g0] ASI_M_MMUREGS, %g1
+                andcc   %g1, 1, %g0
+                be      halt_sun4_or_sun4c
+                 nop
+
 srmmu_remap:
                 /* First, check for a viking (TI) module. */
                 set     0x40000000, %g2