powerpc: Fix crash in early boot on some powermacs

Some powermac machines were crashing in the quiesce firmware call
in prom_init.c because we have just closed the OF stdin device;
notably my 1999 G3 powerbook does this.  To avoid this, don't
close the OF stdin device on powermacs.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 7 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 6dc33d19fc2a..58f0917bd6b6 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -2081,8 +2081,13 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
         prom_printf("copying OF device tree ...\n");
         flatten_device_tree();
 
-        /* in case stdin is USB and still active on IBM machines... */
-        prom_close_stdin();
+        /*
+         * in case stdin is USB and still active on IBM machines...
+         * Unfortunately quiesce crashes on some powermacs if we have
+         * closed stdin already (in particular the powerbook 101).
+         */
+        if (RELOC(of_platform) != PLATFORM_POWERMAC)
+                prom_close_stdin();
 
         /*
          * Call OF "quiesce" method to shut down pending DMA's from