3 files changed, 112 insertions, 98 deletions

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 65484b2200b3..0b47de07302d 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -68,7 +68,8 @@ EXPORT_PER_CPU_SYMBOL(cpu_core_map);
 /* SMP operations for this machine */
 struct smp_ops_t *smp_ops;
 
-static volatile unsigned int cpu_callin_map[NR_CPUS];
+/* Can't be static due to PowerMac hackery */
+volatile unsigned int cpu_callin_map[NR_CPUS];
 
 int smt_enabled_at_boot = 1;
 
diff --git a/arch/powerpc/platforms/powermac/setup.c b/arch/powerpc/platforms/powermac/setup.c
index 86f69a4eb49b..c20522656367 100644
--- a/arch/powerpc/platforms/powermac/setup.c
+++ b/arch/powerpc/platforms/powermac/setup.c
@@ -103,11 +103,6 @@ unsigned long smu_cmdbuf_abs;
 EXPORT_SYMBOL(smu_cmdbuf_abs);
 #endif
 
-#ifdef CONFIG_SMP
-extern struct smp_ops_t psurge_smp_ops;
-extern struct smp_ops_t core99_smp_ops;
-#endif /* CONFIG_SMP */
-
 static void pmac_show_cpuinfo(struct seq_file *m)
 {
         struct device_node *np;
@@ -341,34 +336,6 @@ static void __init pmac_setup_arch(void)
                 ROOT_DEV = DEFAULT_ROOT_DEVICE;
 #endif
 
-#ifdef CONFIG_SMP
-        /* Check for Core99 */
-        ic = of_find_node_by_name(NULL, "uni-n");
-        if (!ic)
-                ic = of_find_node_by_name(NULL, "u3");
-        if (!ic)
-                ic = of_find_node_by_name(NULL, "u4");
-        if (ic) {
-                of_node_put(ic);
-                smp_ops = &core99_smp_ops;
-        }
-#ifdef CONFIG_PPC32
-        else {
-                /*
-                 * We have to set bits in cpu_possible_map here since the
-                 * secondary CPU(s) aren't in the device tree, and
-                 * setup_per_cpu_areas only allocates per-cpu data for
-                 * CPUs in the cpu_possible_map.
-                 */
-                int cpu;
-
-                for (cpu = 1; cpu < 4 && cpu < NR_CPUS; ++cpu)
-                        cpu_set(cpu, cpu_possible_map);
-                smp_ops = &psurge_smp_ops;
-        }
-#endif
-#endif /* CONFIG_SMP */
-
 #ifdef CONFIG_ADB
         if (strstr(cmd_line, "adb_sync")) {
                 extern int __adb_probe_sync;
@@ -512,6 +479,14 @@ static void __init pmac_init_early(void)
 #ifdef CONFIG_PPC64
         iommu_init_early_dart();
 #endif
+
+        /* SMP Init has to be done early as we need to patch up
+         * cpu_possible_map before interrupt stacks are allocated
+         * or kaboom...
+         */
+#ifdef CONFIG_SMP
+        pmac_setup_smp();
+#endif
 }
 
 static int __init pmac_declare_of_platform_devices(void)
diff --git a/arch/powerpc/platforms/powermac/smp.c b/arch/powerpc/platforms/powermac/smp.c
index cf1dbe758890..6d4da7b46b41 100644
--- a/arch/powerpc/platforms/powermac/smp.c
+++ b/arch/powerpc/platforms/powermac/smp.c
@@ -64,10 +64,11 @@
 extern void __secondary_start_pmac_0(void);
 extern int pmac_pfunc_base_install(void);
 
-#ifdef CONFIG_PPC32
+static void (*pmac_tb_freeze)(int freeze);
+static u64 timebase;
+static int tb_req;
 
-/* Sync flag for HW tb sync */
-static volatile int sec_tb_reset = 0;
+#ifdef CONFIG_PPC32
 
 /*
  * Powersurge (old powermac SMP) support.
@@ -294,6 +295,9 @@ static int __init smp_psurge_probe(void)
                 psurge_quad_init();
                 /* All released cards using this HW design have 4 CPUs */
                 ncpus = 4;
+                /* No sure how timebase sync works on those, let's use SW */
+                smp_ops->give_timebase = smp_generic_give_timebase;
+                smp_ops->take_timebase = smp_generic_take_timebase;
         } else {
                 iounmap(quad_base);
                 if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
@@ -308,18 +312,15 @@ static int __init smp_psurge_probe(void)
         psurge_start = ioremap(PSURGE_START, 4);
         psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
 
-        /*
-         * This is necessary because OF doesn't know about the
+        /* This is necessary because OF doesn't know about the
          * secondary cpu(s), and thus there aren't nodes in the
          * device tree for them, and smp_setup_cpu_maps hasn't
-         * set their bits in cpu_possible_map and cpu_present_map.
+         * set their bits in cpu_present_map.
          */
         if (ncpus > NR_CPUS)
                 ncpus = NR_CPUS;
-        for (i = 1; i < ncpus ; ++i) {
+        for (i = 1; i < ncpus ; ++i)
                 cpu_set(i, cpu_present_map);
-                set_hard_smp_processor_id(i, i);
-        }
 
         if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
 
@@ -329,8 +330,14 @@ static int __init smp_psurge_probe(void)
 static void __init smp_psurge_kick_cpu(int nr)
 {
         unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
-        unsigned long a;
-        int i;
+        unsigned long a, flags;
+        int i, j;
+
+        /* Defining this here is evil ... but I prefer hiding that
+         * crap to avoid giving people ideas that they can do the
+         * same.
+         */
+        extern volatile unsigned int cpu_callin_map[NR_CPUS];
 
         /* may need to flush here if secondary bats aren't setup */
         for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
@@ -339,47 +346,52 @@ static void __init smp_psurge_kick_cpu(int nr)
 
         if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
 
+        /* This is going to freeze the timeebase, we disable interrupts */
+        local_irq_save(flags);
+
         out_be32(psurge_start, start);
         mb();
 
         psurge_set_ipi(nr);
+
         /*
          * We can't use udelay here because the timebase is now frozen.
          */
         for (i = 0; i < 2000; ++i)
-                barrier();
+                asm volatile("nop" : : : "memory");
         psurge_clr_ipi(nr);
 
-        if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
-}
-
-/*
- * With the dual-cpu powersurge board, the decrementers and timebases
- * of both cpus are frozen after the secondary cpu is started up,
- * until we give the secondary cpu another interrupt.  This routine
- * uses this to get the timebases synchronized.
- *  -- paulus.
- */
-static void __init psurge_dual_sync_tb(int cpu_nr)
-{
-        int t;
-
-        set_dec(tb_ticks_per_jiffy);
-        /* XXX fixme */
-        set_tb(0, 0);
-
-        if (cpu_nr > 0) {
+        /*
+         * Also, because the timebase is frozen, we must not return to the
+         * caller which will try to do udelay's etc... Instead, we wait -here-
+         * for the CPU to callin.
+         */
+        for (i = 0; i < 100000 && !cpu_callin_map[nr]; ++i) {
+                for (j = 1; j < 10000; j++)
+                        asm volatile("nop" : : : "memory");
+                asm volatile("sync" : : : "memory");
+        }
+        if (!cpu_callin_map[nr])
+                goto stuck;
+
+        /* And we do the TB sync here too for standard dual CPU cards */
+        if (psurge_type == PSURGE_DUAL) {
+                while(!tb_req)
+                        barrier();
+                tb_req = 0;
+                mb();
+                timebase = get_tb();
+                mb();
+                while (timebase)
+                        barrier();
                 mb();
-                sec_tb_reset = 1;
-                return;
         }
+ stuck:
+        /* now interrupt the secondary, restarting both TBs */
+        if (psurge_type == PSURGE_DUAL)
+                psurge_set_ipi(1);
 
-        /* wait for the secondary to have reset its TB before proceeding */
-        for (t = 10000000; t > 0 && !sec_tb_reset; --t)
-                ;
-
-        /* now interrupt the secondary, starting both TBs */
-        psurge_set_ipi(1);
+        if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
 }
 
 static struct irqaction psurge_irqaction = {
@@ -390,36 +402,35 @@ static struct irqaction psurge_irqaction = {
 
 static void __init smp_psurge_setup_cpu(int cpu_nr)
 {
+        if (cpu_nr != 0)
+                return;
 
-        if (cpu_nr == 0) {
-                /* If we failed to start the second CPU, we should still
-                 * send it an IPI to start the timebase & DEC or we might
-                 * have them stuck.
-                 */
-                if (num_online_cpus() < 2) {
-                        if (psurge_type == PSURGE_DUAL)
-                                psurge_set_ipi(1);
-                        return;
-                }
-                /* reset the entry point so if we get another intr we won't
-                 * try to startup again */
-                out_be32(psurge_start, 0x100);
-                if (setup_irq(30, &psurge_irqaction))
-                        printk(KERN_ERR "Couldn't get primary IPI interrupt");
-        }
-
-        if (psurge_type == PSURGE_DUAL)
-                psurge_dual_sync_tb(cpu_nr);
+        /* reset the entry point so if we get another intr we won't
+         * try to startup again */
+        out_be32(psurge_start, 0x100);
+        if (setup_irq(30, &psurge_irqaction))
+                printk(KERN_ERR "Couldn't get primary IPI interrupt");
 }
 
 void __init smp_psurge_take_timebase(void)
 {
-        /* Dummy implementation */
+        if (psurge_type != PSURGE_DUAL)
+                return;
+
+        tb_req = 1;
+        mb();
+        while (!timebase)
+                barrier();
+        mb();
+        set_tb(timebase >> 32, timebase & 0xffffffff);
+        timebase = 0;
+        mb();
+        set_dec(tb_ticks_per_jiffy/2);
 }
 
 void __init smp_psurge_give_timebase(void)
 {
-        /* Dummy implementation */
+        /* Nothing to do here */
 }
 
 /* PowerSurge-style Macs */
@@ -437,9 +448,6 @@ struct smp_ops_t psurge_smp_ops = {
  * Core 99 and later support
  */
 
-static void (*pmac_tb_freeze)(int freeze);
-static u64 timebase;
-static int tb_req;
 
 static void smp_core99_give_timebase(void)
 {
@@ -478,7 +486,6 @@ static void __devinit smp_core99_take_timebase(void)
         set_tb(timebase >> 32, timebase & 0xffffffff);
         timebase = 0;
         mb();
-        set_dec(tb_ticks_per_jiffy/2);
 
         local_irq_restore(flags);
 }
@@ -920,3 +927,34 @@ struct smp_ops_t core99_smp_ops = {
 # endif
 #endif
 };
+
+void __init pmac_setup_smp(void)
+{
+        struct device_node *np;
+
+        /* Check for Core99 */
+        np = of_find_node_by_name(NULL, "uni-n");
+        if (!np)
+                np = of_find_node_by_name(NULL, "u3");
+        if (!np)
+                np = of_find_node_by_name(NULL, "u4");
+        if (np) {
+                of_node_put(np);
+                smp_ops = &core99_smp_ops;
+        }
+#ifdef CONFIG_PPC32
+        else {
+                /* We have to set bits in cpu_possible_map here since the
+                 * secondary CPU(s) aren't in the device tree. Various
+                 * things won't be initialized for CPUs not in the possible
+                 * map, so we really need to fix it up here.
+                 */
+                int cpu;
+
+                for (cpu = 1; cpu < 4 && cpu < NR_CPUS; ++cpu)
+                        cpu_set(cpu, cpu_possible_map);
+                smp_ops = &psurge_smp_ops;
+        }
+#endif /* CONFIG_PPC32 */
+}
+