powerpc: Don't skip ePAPR spin-table CPUs

commit 6663a4fa6711050036562ddfd2086edf735fae21 upstream.

Commit 59a53afe70fd530040bdc69581f03d880157f15a "powerpc: Don't setup
CPUs with bad status" broke ePAPR SMP booting.  ePAPR says that CPUs
that aren't presently running shall have status of disabled, with
enable-method being used to determine whether the CPU can be enabled.

Fix by checking for spin-table, which is currently the only supported
enable-method.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jonathan Toppins <jtoppins@cumulusnetworks.com>

diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 675cbcf8c3f2d1fad4294295aa3e96b74f6ca448..83940d7bf2386807cb490ea8c74daebc49044d69 100644 (file)
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -447,9 +447,17 @@ void __init smp_setup_cpu_maps(void)
                }
 
                for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
+                       bool avail;
+
                        DBG("    thread %d -> cpu %d (hard id %d)\n",
                            j, cpu, be32_to_cpu(intserv[j]));
-                       set_cpu_present(cpu, of_device_is_available(dn));
+
+                       avail = of_device_is_available(dn);
+                       if (!avail)
+                               avail = !of_property_match_string(dn,
+                                               "enable-method", "spin-table");
+
+                       set_cpu_present(cpu, avail);
                        set_hard_smp_processor_id(cpu, be32_to_cpu(intserv[j]));
                        set_cpu_possible(cpu, true);
                        cpu++;