[SPARC64]: Make smp_processor_id() functional before start_kernel()

Uses of smp_processor_id() get pushed earlier and earlier in
the start_kernel() sequence.  So just get it working before
we call start_kernel() to avoid all possible problems.

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 44 insertions, 25 deletions

diff --git a/arch/sparc64/kernel/head.S b/arch/sparc64/kernel/head.S
index 3eadac5e171e..31c5892f5acc 100644
--- a/arch/sparc64/kernel/head.S
+++ b/arch/sparc64/kernel/head.S
@@ -10,6 +10,7 @@
 #include <linux/config.h>
 #include <linux/version.h>
 #include <linux/errno.h>
+#include <linux/threads.h>
 #include <asm/thread_info.h>
 #include <asm/asi.h>
 #include <asm/pstate.h>
@@ -493,6 +494,35 @@ tlb_fixup_done:
         call    prom_init
          mov    %l7, %o0                        ! OpenPROM cif handler
 
+        /* Initialize current_thread_info()->cpu as early as possible.
+         * In order to do that accurately we have to patch up the get_cpuid()
+         * assembler sequences.  And that, in turn, requires that we know
+         * if we are on a Starfire box or not.  While we're here, patch up
+         * the sun4v sequences as well.
+         */
+        call    check_if_starfire
+         nop
+        call    per_cpu_patch
+         nop
+        call    sun4v_patch
+         nop
+
+#ifdef CONFIG_SMP
+        call    hard_smp_processor_id
+         nop
+        cmp     %o0, NR_CPUS
+        blu,pt  %xcc, 1f
+         nop
+        call    boot_cpu_id_too_large
+         nop
+        /* Not reached... */
+
+1:
+#else
+        mov     0, %o0
+#endif
+        stb     %o0, [%g6 + TI_CPU]
+
         /* Off we go.... */
         call    start_kernel
          nop
diff --git a/arch/sparc64/kernel/setup.c b/arch/sparc64/kernel/setup.c
index 005167f82419..9cf1c88cd774 100644
--- a/arch/sparc64/kernel/setup.c
+++ b/arch/sparc64/kernel/setup.c
@@ -220,7 +220,7 @@ char reboot_command[COMMAND_LINE_SIZE];
 
 static struct pt_regs fake_swapper_regs = { { 0, }, 0, 0, 0, 0 };
 
-static void __init per_cpu_patch(void)
+void __init per_cpu_patch(void)
 {
         struct cpuid_patch_entry *p;
         unsigned long ver;
@@ -280,7 +280,7 @@ static void __init per_cpu_patch(void)
         }
 }
 
-static void __init sun4v_patch(void)
+void __init sun4v_patch(void)
 {
         struct sun4v_1insn_patch_entry *p1;
         struct sun4v_2insn_patch_entry *p2;
@@ -315,6 +315,15 @@ static void __init sun4v_patch(void)
         }
 }
 
+#ifdef CONFIG_SMP
+void __init boot_cpu_id_too_large(int cpu)
+{
+        prom_printf("Serious problem, boot cpu id (%d) >= NR_CPUS (%d)\n",
+                    cpu, NR_CPUS);
+        prom_halt();
+}
+#endif
+
 void __init setup_arch(char **cmdline_p)
 {
         /* Initialize PROM console and command line. */
@@ -332,16 +341,6 @@ void __init setup_arch(char **cmdline_p)
         conswitchp = &prom_con;
 #endif
 
-        /* Work out if we are starfire early on */
-        check_if_starfire();
-
-        /* Now we know enough to patch the get_cpuid sequences
-         * used by trap code.
-         */
-        per_cpu_patch();
-
-        sun4v_patch();
-
         boot_flags_init(*cmdline_p);
 
         idprom_init();
diff --git a/arch/sparc64/kernel/smp.c b/arch/sparc64/kernel/smp.c
index 90eaca3ec9a6..4e8cd79156e0 100644
--- a/arch/sparc64/kernel/smp.c
+++ b/arch/sparc64/kernel/smp.c
@@ -1264,7 +1264,6 @@ void __init smp_tick_init(void)
         boot_cpu_id = hard_smp_processor_id();
         current_tick_offset = timer_tick_offset;
 
-        cpu_set(boot_cpu_id, cpu_online_map);
         prof_counter(boot_cpu_id) = prof_multiplier(boot_cpu_id) = 1;
 }
 
@@ -1345,18 +1344,6 @@ void __init smp_setup_cpu_possible_map(void)
 
 void __devinit smp_prepare_boot_cpu(void)
 {
-        int cpu = hard_smp_processor_id();
-
-        if (cpu >= NR_CPUS) {
-                prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
-                prom_halt();
-        }
-
-        current_thread_info()->cpu = cpu;
-        __local_per_cpu_offset = __per_cpu_offset(cpu);
-
-        cpu_set(smp_processor_id(), cpu_online_map);
-        cpu_set(smp_processor_id(), phys_cpu_present_map);
 }
 
 int __devinit __cpu_up(unsigned int cpu)
@@ -1433,4 +1420,7 @@ void __init setup_per_cpu_areas(void)
 
         for (i = 0; i < NR_CPUS; i++, ptr += size)
                 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
+
+        /* Setup %g5 for the boot cpu.  */
+        __local_per_cpu_offset = __per_cpu_offset(smp_processor_id());
 }