[MIPS] SMP: Fix initialization order bug.

    
A recent change requires cpu_possible_map to be initialized before
smp_sched_init() but most MIPS platforms were initializing their
processors in the prom_prepare_cpus callback of smp_prepare_cpus.  The
simple fix of calling prom_prepare_cpus from one of the earlier SMP
initialization hooks doesn't work well either since IPIs may require
init_IRQ() to have completed, so bit the bullet and split
prom_prepare_cpus into two initialization functions, plat_smp_setup
which is called early from setup_arch and plat_prepare_cpus called where
prom_prepare_cpus used to be called.
    
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 6 insertions, 18 deletions

diff --git a/arch/mips/pmc-sierra/yosemite/smp.c b/arch/mips/pmc-sierra/yosemite/smp.c
index 7f8fda9..c197311 100644
--- a/arch/mips/pmc-sierra/yosemite/smp.c
+++ b/arch/mips/pmc-sierra/yosemite/smp.c
@@ -50,37 +50,25 @@ void __init prom_grab_secondary(void)
  * We don't want to start the secondary CPU yet nor do we have a nice probing
  * feature in PMON so we just assume presence of the secondary core.
  */
-static char maxcpus_string[] __initdata =
-	KERN_WARNING "max_cpus set to 0; using 1 instead\n";
-
-void __init prom_prepare_cpus(unsigned int max_cpus)
+void __init plat_smp_setup(void)
 {
-	int enabled = 0, i;
-
-	if (max_cpus == 0) {
-		printk(maxcpus_string);
-		max_cpus = 1;
-	}
+	int i;
 
 	cpus_clear(phys_cpu_present_map);
 
 	for (i = 0; i < 2; i++) {
-		if (i == max_cpus)
-			break;
-
-		/*
-		 * The boot CPU
-		 */
 		cpu_set(i, phys_cpu_present_map);
 		__cpu_number_map[i]	= i;
 		__cpu_logical_map[i]	= i;
-		enabled++;
 	}
+}
 
+void __init plat_prepare_cpus(unsigned int max_cpus)
+{
 	/*
 	 * Be paranoid.  Enable the IPI only if we're really about to go SMP.
 	 */
-	if (enabled > 1)
+	if (cpus_weight(cpu_possible_map))
 		set_c0_status(STATUSF_IP5);
 }