powerpc: kill useless SMT code in prom_hold_cpus

This piece of code is broken for >2 threads, and possibly in some
other subtle ways (such as comparing a value obtained from an
"ibm,ppc-interrupt-server#s" property to a value obtained from a
"reg" property) and doesn't seem to have any useful purpose in the
first place other than a dubious warning in case NR_CPUS is too
small, which probably isn't the right place to do so.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index c4ab219..b72849a 100644 (file)
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -205,8 +205,6 @@ static int __initdata mem_reserve_cnt;
 static cell_t __initdata regbuf[1024];
 
 
-#define MAX_CPU_THREADS 2
-
 /*
  * Error results ... some OF calls will return "-1" on error, some
  * will return 0, some will return either. To simplify, here are
@@ -1339,10 +1337,6 @@ static void __init prom_hold_cpus(void)
        unsigned int reg;
        phandle node;
        char type[64];
-       int cpuid = 0;
-       unsigned int interrupt_server[MAX_CPU_THREADS];
-       unsigned int cpu_threads, hw_cpu_num;
-       int propsize;
        struct prom_t *_prom = &RELOC(prom);
        unsigned long *spinloop
                = (void *) LOW_ADDR(__secondary_hold_spinloop);
@@ -1386,7 +1380,6 @@ static void __init prom_hold_cpus(void)
                reg = -1;
                prom_getprop(node, "reg", &reg, sizeof(reg));
 
-               prom_debug("\ncpuid        = 0x%x\n", cpuid);
                prom_debug("cpu hw idx   = 0x%x\n", reg);
 
                /* Init the acknowledge var which will be reset by
@@ -1395,28 +1388,9 @@ static void __init prom_hold_cpus(void)
                 */
                *acknowledge = (unsigned long)-1;
 
-               propsize = prom_getprop(node, "ibm,ppc-interrupt-server#s",
-                                       &interrupt_server,
-                                       sizeof(interrupt_server));
-               if (propsize < 0) {
-                       /* no property.  old hardware has no SMT */
-                       cpu_threads = 1;
-                       interrupt_server[0] = reg; /* fake it with phys id */
-               } else {
-                       /* We have a threaded processor */
-                       cpu_threads = propsize / sizeof(u32);
-                       if (cpu_threads > MAX_CPU_THREADS) {
-                               prom_printf("SMT: too many threads!\n"
-                                           "SMT: found %x, max is %x\n",
-                                           cpu_threads, MAX_CPU_THREADS);
-                               cpu_threads = 1; /* ToDo: panic? */
-                       }
-               }
-
-               hw_cpu_num = interrupt_server[0];
-               if (hw_cpu_num != _prom->cpu) {
+               if (reg != _prom->cpu) {
                        /* Primary Thread of non-boot cpu */
-                       prom_printf("%x : starting cpu hw idx %x... ", cpuid, reg);
+                       prom_printf("starting cpu hw idx %x... ", reg);
                        call_prom("start-cpu", 3, 0, node,
                                  secondary_hold, reg);
 
@@ -1431,17 +1405,10 @@ static void __init prom_hold_cpus(void)
                }
 #ifdef CONFIG_SMP
                else
-                       prom_printf("%x : boot cpu     %x\n", cpuid, reg);
+                       prom_printf("boot cpu hw idx %x\n", reg);
 #endif /* CONFIG_SMP */
-
-               /* Reserve cpu #s for secondary threads.   They start later. */
-               cpuid += cpu_threads;
        }
 
-       if (cpuid > NR_CPUS)
-               prom_printf("WARNING: maximum CPUs (" __stringify(NR_CPUS)
-                           ") exceeded: ignoring extras\n");
-
        prom_debug("prom_hold_cpus: end...\n");
 }