[SPARC32]: Rework the CPU enumeration and probing code

The low 2 bits of the MID are now used exclusively as the software
CPU ID on 4m.  This eliminates entirely the need for mid_xlate.  We
also eliminate linux_num_cpus and linux_cpus; since the hardware-based
id is now used everywhere we don't need indexed CPU tables.

The device probe is almost identical to sparc64's version.  The one
exception is that 4m only uses the bottom 2 bits of the MID, so we also
have a separate function to get the true hardware MID for the rare times
it's actually needed.

Per-cpu data is now used the same way as in sparc64.  As a side benefit
we now display the same format Bogo and Clock values in /proc/cpuinfo.

arch/sparc/kernel/cpu.c

@@ -4,6 +4,7 @@
  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  */
 
+#include <linux/config.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/smp.h>
@@ -13,6 +14,9 @@
 #include <asm/head.h>
 #include <asm/psr.h>
 #include <asm/mbus.h>
+#include <asm/cpudata.h>
+
+DEFINE_PER_CPU(cpuinfo_sparc, __cpu_data) = { 0 };
 
 struct cpu_iu_info {
   int psr_impl;
@@ -118,17 +122,15 @@ struct cpu_iu_info linux_sparc_chips[] = {
 
 #define NSPARCCHIPS  (sizeof(linux_sparc_chips)/sizeof(struct cpu_iu_info))
 
-char *sparc_cpu_type[NR_CPUS] = { 0 };
-char *sparc_fpu_type[NR_CPUS] = { 0 };
+char *sparc_cpu_type;
+char *sparc_fpu_type;
 
 unsigned int fsr_storage;
 
 void __init cpu_probe(void)
 {
 	int psr_impl, psr_vers, fpu_vers;
-	int i, cpuid, psr;
-
-	cpuid = hard_smp_processor_id();
+	int i, psr;
 
 	psr_impl = ((get_psr()>>28)&0xf);
 	psr_vers = ((get_psr()>>24)&0xf);
@@ -141,7 +143,7 @@ void __init cpu_probe(void)
 	for(i = 0; i<NSPARCCHIPS; i++) {
 		if(linux_sparc_chips[i].psr_impl == psr_impl)
 			if(linux_sparc_chips[i].psr_vers == psr_vers) {
-				sparc_cpu_type[cpuid] = linux_sparc_chips[i].cpu_name;
+				sparc_cpu_type = linux_sparc_chips[i].cpu_name;
 				break;
 			}
 	}
@@ -153,7 +155,7 @@ void __init cpu_probe(void)
 	for(i = 0; i<NSPARCFPU; i++) {
 		if(linux_sparc_fpu[i].psr_impl == psr_impl)
 			if(linux_sparc_fpu[i].fp_vers == fpu_vers) {
-				sparc_fpu_type[cpuid] = linux_sparc_fpu[i].fp_name;
+				sparc_fpu_type = linux_sparc_fpu[i].fp_name;
 				break;
 			}
 	}
@@ -161,6 +163,6 @@ void __init cpu_probe(void)
 	if(i == NSPARCFPU) {
 		printk("DEBUG: psr.impl = 0x%x  fsr.vers = 0x%x\n", psr_impl,
 			    fpu_vers);
-		sparc_fpu_type[cpuid] = linux_sparc_fpu[31].fp_name;
+		sparc_fpu_type = linux_sparc_fpu[31].fp_name;
 	}
 }

arch/sparc/kernel/devices.c

 /* devices.c: Initial scan of the prom device tree for important
  *	      Sparc device nodes which we need to find.
  *
+ * This is based on the sparc64 version, but sun4m doesn't always use
+ * the hardware MIDs, so be careful.
+ *
  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  */
 
@@ -9,73 +12,135 @@
 #include <linux/threads.h>
 #include <linux/string.h>
 #include <linux/init.h>
+#include <linux/errno.h>
 
 #include <asm/page.h>
 #include <asm/oplib.h>
 #include <asm/smp.h>
 #include <asm/system.h>
-
-struct prom_cpuinfo linux_cpus[32];
-int linux_num_cpus = 0;
+#include <asm/cpudata.h>
 
 extern void cpu_probe(void);
 extern void clock_stop_probe(void); /* tadpole.c */
 extern void sun4c_probe_memerr_reg(void);
 
-void __init
-device_scan(void)
+static char *cpu_mid_prop(void)
+{
+	if (sparc_cpu_model == sun4d)
+		return "cpu-id";
+	return "mid";
+}
+
+static int check_cpu_node(int nd, int *cur_inst,
+			  int (*compare)(int, int, void *), void *compare_arg,
+			  int *prom_node, int *mid)
 {
 	char node_str[128];
-	int thismid;
 
-	prom_getstring(prom_root_node, "device_type", node_str, sizeof(node_str));
+	prom_getstring(nd, "device_type", node_str, sizeof(node_str));
+	if (strcmp(node_str, "cpu"))
+		return -ENODEV;
+	
+	if (!compare(nd, *cur_inst, compare_arg)) {
+		if (prom_node)
+			*prom_node = nd;
+		if (mid) {
+			*mid = prom_getintdefault(nd, cpu_mid_prop(), 0);
+			if (sparc_cpu_model == sun4m)
+				*mid &= 3;
+		}
+		return 0;
+	}
+
+	(*cur_inst)++;
 
+	return -ENODEV;
+}
+
+static int __cpu_find_by(int (*compare)(int, int, void *), void *compare_arg,
+			 int *prom_node, int *mid)
+{
+	int nd, cur_inst, err;
+
+	nd = prom_root_node;
+	cur_inst = 0;
+
+	err = check_cpu_node(nd, &cur_inst, compare, compare_arg,
+			     prom_node, mid);
+	if (!err)
+		return 0;
+
+	nd = prom_getchild(nd);
+	while ((nd = prom_getsibling(nd)) != 0) {
+		err = check_cpu_node(nd, &cur_inst, compare, compare_arg,
+				     prom_node, mid);
+		if (!err)
+			return 0;
+	}
+
+	return -ENODEV;
+}
+
+static int cpu_instance_compare(int nd, int instance, void *_arg)
+{
+	int desired_instance = (int) _arg;
+
+	if (instance == desired_instance)
+		return 0;
+	return -ENODEV;
+}
+
+int cpu_find_by_instance(int instance, int *prom_node, int *mid)
+{
+	return __cpu_find_by(cpu_instance_compare, (void *)instance,
+			     prom_node, mid);
+}
+
+static int cpu_mid_compare(int nd, int instance, void *_arg)
+{
+	int desired_mid = (int) _arg;
+	int this_mid;
+
+	this_mid = prom_getintdefault(nd, cpu_mid_prop(), 0);
+	if (this_mid == desired_mid
+	    || (sparc_cpu_model == sun4m && (this_mid & 3) == desired_mid))
+		return 0;
+	return -ENODEV;
+}
+
+int cpu_find_by_mid(int mid, int *prom_node)
+{
+	return __cpu_find_by(cpu_mid_compare, (void *)mid,
+			     prom_node, NULL);
+}
+
+/* sun4m uses truncated mids since we base the cpuid on the ttable/irqset
+ * address (0-3).  This gives us the true hardware mid, which might have
+ * some other bits set.  On 4d hardware and software mids are the same.
+ */
+int cpu_get_hwmid(int prom_node)
+{
+	return prom_getintdefault(prom_node, cpu_mid_prop(), -ENODEV);
+}
+
+void __init device_scan(void)
+{
 	prom_printf("Booting Linux...\n");
-	if(strcmp(node_str, "cpu") == 0) {
-		linux_num_cpus++;
-	} else {
-		int scan;
-		scan = prom_getchild(prom_root_node);
-		/* One can look it up in PROM instead */
-		while ((scan = prom_getsibling(scan)) != 0) {
-			prom_getstring(scan, "device_type",
-				       node_str, sizeof(node_str));
-			if (strcmp(node_str, "cpu") == 0) {
-				linux_cpus[linux_num_cpus].prom_node = scan;
-				prom_getproperty(scan, "mid",
-						 (char *) &thismid, sizeof(thismid));
-				linux_cpus[linux_num_cpus].mid = thismid;
-				printk("Found CPU %d <node=%08lx,mid=%d>\n",
-				       linux_num_cpus, (unsigned long) scan, thismid);
-				linux_num_cpus++;
-			}
-		}
-		if (linux_num_cpus == 0 && sparc_cpu_model == sun4d) {
-			scan = prom_getchild(prom_root_node);
-			for (scan = prom_searchsiblings(scan, "cpu-unit"); scan;
-			     scan = prom_searchsiblings(prom_getsibling(scan), "cpu-unit")) {
-				int node = prom_getchild(scan);
-
-				prom_getstring(node, "device_type",
-					       node_str, sizeof(node_str));
-				if (strcmp(node_str, "cpu") == 0) {
-					prom_getproperty(node, "cpu-id",
-							 (char *) &thismid, sizeof(thismid));
-					linux_cpus[linux_num_cpus].prom_node = node;
-					linux_cpus[linux_num_cpus].mid = thismid;
-					printk("Found CPU %d <node=%08lx,mid=%d>\n", 
-					       linux_num_cpus, (unsigned long) node, thismid);
-					linux_num_cpus++;
-				}
-			}
-		}
-		if (linux_num_cpus == 0) {
-			printk("No CPU nodes found, cannot continue.\n");
+
+#ifndef CONFIG_SMP
+	{
+		int err, cpu_node;
+		err = cpu_find_by_instance(0, &cpu_node, NULL);
+		if (err) {
 			/* Probably a sun4e, Sun is trying to trick us ;-) */
+			prom_printf("No cpu nodes, cannot continue\n");
 			prom_halt();
 		}
-		printk("Found %d CPU prom device tree node(s).\n", linux_num_cpus);
+		cpu_data(0).clock_tick = prom_getintdefault(cpu_node,
+							    "clock-frequency",
+							    0);
 	}
+#endif /* !CONFIG_SMP */
 
 	cpu_probe();
 #ifdef CONFIG_SUN_AUXIO

arch/sparc/kernel/entry.S

@@ -349,7 +349,7 @@ smp4m_ticker:
 	 * for cross calls.  That has a separate entry point below.
 	 */
 maybe_smp4m_msg:
-	GET_PROCESSOR_MID(o3, o2)
+	GET_PROCESSOR_MID(o3)
 	set	sun4m_interrupts, %l5
 	ld	[%l5], %o5
 	sethi	%hi(0x60000000), %o4
@@ -389,7 +389,7 @@ maybe_smp4m_msg:
 linux_trap_ipi15_sun4m:
 	SAVE_ALL
 	sethi	%hi(0x80000000), %o2
-	GET_PROCESSOR_MID(o0, o1)
+	GET_PROCESSOR_MID(o0)
 	set	sun4m_interrupts, %l5
 	ld	[%l5], %o5
 	sll	%o0, 12, %o0

arch/sparc/kernel/setup.c

@@ -45,6 +45,7 @@
 #include <asm/idprom.h>
 #include <asm/hardirq.h>
 #include <asm/machines.h>
+#include <asm/cpudata.h>
 
 struct screen_info screen_info = {
 	0, 0,			/* orig-x, orig-y */
@@ -395,13 +396,11 @@ asmlinkage int sys_ioperm(unsigned long from, unsigned long num, int on)
 	return -EIO;
 }
 
-extern char *sparc_cpu_type[];
-extern char *sparc_fpu_type[];
+extern char *sparc_cpu_type;
+extern char *sparc_fpu_type;
 
 static int show_cpuinfo(struct seq_file *m, void *__unused)
 {
-	int cpuid = hard_smp_processor_id();
-
 	seq_printf(m,
 		   "cpu\t\t: %s\n"
 		   "fpu\t\t: %s\n"
@@ -411,26 +410,28 @@ static int show_cpuinfo(struct seq_file *m, void *__unused)
 		   "ncpus probed\t: %d\n"
 		   "ncpus active\t: %d\n"
 #ifndef CONFIG_SMP
-		   "BogoMips\t: %lu.%02lu\n"
+		   "CPU0Bogo\t: %lu.%02lu\n"
+		   "CPU0ClkTck\t: %ld\n"
 #endif
 		   ,
-		   sparc_cpu_type[cpuid] ? : "undetermined",
-		   sparc_fpu_type[cpuid] ? : "undetermined",
+		   sparc_cpu_type ? sparc_cpu_type : "undetermined",
+		   sparc_fpu_type ? sparc_fpu_type : "undetermined",
 		   romvec->pv_romvers,
 		   prom_rev,
 		   romvec->pv_printrev >> 16,
-		   (short) romvec->pv_printrev,
+		   romvec->pv_printrev & 0xffff,
 		   &cputypval,
-		   linux_num_cpus,
+		   num_possible_cpus(),
 		   num_online_cpus()
 #ifndef CONFIG_SMP
-		   , loops_per_jiffy/(500000/HZ),
-		   (loops_per_jiffy/(5000/HZ)) % 100
+		   , cpu_data(0).udelay_val/(500000/HZ),
+		   (cpu_data(0).udelay_val/(5000/HZ)) % 100,
+		   cpu_data(0).clock_tick
 #endif
 		);
 
 #ifdef CONFIG_SMP
-	smp_bogo_info(m);
+	smp_bogo(m);
 #endif
 	mmu_info(m);
 #ifdef CONFIG_SMP

arch/sparc/kernel/smp.c

@@ -2,6 +2,7 @@
  *
  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (C) 2004 Keith M Wesolowski (wesolows@foobazco.org)
  */
 
 #include <asm/head.h>
@@ -32,26 +33,15 @@
 #include <asm/hardirq.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
+#include <asm/cpudata.h>
 
 #define __KERNEL_SYSCALLS__
 #include <linux/unistd.h>
 
-#define IRQ_RESCHEDULE		13
-#define IRQ_STOP_CPU		14
-#define IRQ_CROSS_CALL		15
-
 volatile int smp_processors_ready = 0;
-unsigned long cpu_present_map = 0;
 int smp_num_cpus = 1;
 int smp_threads_ready=0;
-unsigned char mid_xlate[NR_CPUS] = { 0, 0, 0, 0, };
 volatile unsigned long cpu_callin_map[NR_CPUS] __initdata = {0,};
-#ifdef NOTUSED
-volatile unsigned long smp_spinning[NR_CPUS] = { 0, };
-#endif
-unsigned long smp_proc_in_lock[NR_CPUS] = { 0, };
-struct cpuinfo_sparc cpu_data[NR_CPUS];
-unsigned long cpu_offset[NR_CPUS];
 unsigned char boot_cpu_id = 0;
 unsigned char boot_cpu_id4 = 0; /* boot_cpu_id << 2 */
 int smp_activated = 0;
@@ -59,6 +49,10 @@ volatile int __cpu_number_map[NR_CPUS];
 volatile int __cpu_logical_map[NR_CPUS];
 cycles_t cacheflush_time = 0; /* XXX */
 
+cpumask_t cpu_online_map = CPU_MASK_NONE;
+atomic_t sparc_num_cpus_possible = ATOMIC_INIT(0);
+cpumask_t phys_cpu_present_map = CPU_MASK_NONE;
+
 /* The only guaranteed locking primitive available on all Sparc
  * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically
  * places the current byte at the effective address into dest_reg and
@@ -75,40 +69,23 @@ volatile unsigned long ipi_count;
 volatile int smp_process_available=0;
 volatile int smp_commenced = 0;
 
-/* Not supported on Sparc yet. */
-void __init smp_setup(char *str, int *ints)
-{
-}
-
-/*
- *	The bootstrap kernel entry code has set these up. Save them for
- *	a given CPU
- */
-
 void __init smp_store_cpu_info(int id)
 {
-	cpu_data[id].udelay_val = loops_per_jiffy; /* this is it on sparc. */
-}
+	int cpu_node;
 
-void __init smp_commence(void)
-{
-	/*
-	 *	Lets the callin's below out of their loop.
-	 */
-	local_flush_cache_all();
-	local_flush_tlb_all();
-	smp_commenced = 1;
-	local_flush_cache_all();
-	local_flush_tlb_all();
-}
+	cpu_data(id).udelay_val = loops_per_jiffy;
 
-extern int cpu_idle(void);
+	cpu_find_by_mid(id, &cpu_node);
+	cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
+						     "clock-frequency", 0);
+	cpu_data(id).prom_node = cpu_node;
+	cpu_data(id).mid = cpu_get_hwmid(cpu_node);
+	if (cpu_data(id).mid < 0)
+		panic("No MID found for CPU%d at node 0x%08d", id, cpu_node);
+}
 
-/* Activate a secondary processor. */
-int start_secondary(void *unused)
+void __init smp_cpus_done(unsigned int max_cpus)
 {
-	prom_printf("Start secondary called. Should not happen\n");
-	return cpu_idle();
 }
 
 void cpu_panic(void)
@@ -117,11 +94,6 @@ void cpu_panic(void)
 	panic("SMP bolixed\n");
 }
 
-/*
- *	Cycle through the processors asking the PROM to start each one.
- */
- 
-extern struct prom_cpuinfo linux_cpus[NR_CPUS];
 struct linux_prom_registers smp_penguin_ctable __initdata = { 0 };
 
 void __init smp_boot_cpus(void)
@@ -137,12 +109,11 @@ void __init smp_boot_cpus(void)
 
 void smp_send_reschedule(int cpu)
 {
-	smp_message_pass (cpu, MSG_RESCHEDULE, 0, 0);
+	/* See sparc64 */
 }
 
 void smp_send_stop(void)
 {
-	smp_message_pass (MSG_ALL_BUT_SELF, MSG_STOP_CPU, 0, 0);
 }
 
 void smp_flush_cache_all(void)
@@ -245,22 +216,6 @@ void smp_flush_sig_insns(struct mm_struct *mm, unsigned long insn_addr)
 	local_flush_sig_insns(mm, insn_addr);
 }
 
-/* Reschedule call back. */
-void smp_reschedule_irq(void)
-{
-	current->work.need_resched = 1;
-}
-
-/* Stopping processors. */
-void smp_stop_cpu_irq(void)
-{
-	local_irq_enable();
-	while(1)
-		barrier();
-}
-
-unsigned int prof_multiplier[NR_CPUS];
-unsigned int prof_counter[NR_CPUS];
 extern unsigned int lvl14_resolution;
 
 /* /proc/profile writes can call this, don't __init it please. */
@@ -277,36 +232,52 @@ int setup_profiling_timer(unsigned int multiplier)
 
 	spin_lock_irqsave(&prof_setup_lock, flags);
 	for(i = 0; i < NR_CPUS; i++) {
-		if(cpu_present_map & (1 << i)) {
-			load_profile_irq(mid_xlate[i], lvl14_resolution / multiplier);
-			prof_multiplier[i] = multiplier;
-		}
+		if (cpu_possible(i))
+			load_profile_irq(i, lvl14_resolution / multiplier);
+		prof_multiplier(i) = multiplier;
 	}
 	spin_unlock_irqrestore(&prof_setup_lock, flags);
 
 	return 0;
 }
 
-void smp_bogo_info(struct seq_file *m)
+void __init smp_prepare_cpus(unsigned int maxcpus)
+{
+}
+
+void __devinit smp_prepare_boot_cpu(void)
+{
+	current_thread_info()->cpu = hard_smp_processor_id();
+	cpu_set(smp_processor_id(), cpu_online_map);
+	cpu_set(smp_processor_id(), phys_cpu_present_map);
+}
+
+int __devinit __cpu_up(unsigned int cpu)
+{
+	panic("smp doesn't work\n");
+}
+
+void smp_bogo(struct seq_file *m)
 {
 	int i;
 	
 	for (i = 0; i < NR_CPUS; i++) {
-		if (cpu_present_map & (1 << i))
+		if (cpu_online(i))
 			seq_printf(m,
 				   "Cpu%dBogo\t: %lu.%02lu\n", 
 				   i,
-				   cpu_data[i].udelay_val/(500000/HZ),
-				   (cpu_data[i].udelay_val/(5000/HZ))%100);
+				   cpu_data(i).udelay_val/(500000/HZ),
+				   (cpu_data(i).udelay_val/(5000/HZ))%100);
 	}
 }
 
 void smp_info(struct seq_file *m)
 {
 	int i;
-	
+
+	seq_printf(m, "State:\n");
 	for (i = 0; i < NR_CPUS; i++) {
-		if (cpu_present_map & (1 << i))
+		if (cpu_online(i))
 			seq_printf(m, "CPU%d\t\t: online\n", i);
 	}
 }

arch/sparc/kernel/sun4d_irq.c

@@ -472,9 +472,9 @@ static void sun4d_load_profile_irq(int cpu, unsigned int limit)
 static void __init sun4d_init_timers(irqreturn_t (*counter_fn)(int, void *, struct pt_regs *))
 {
 	int irq;
-	extern struct prom_cpuinfo linux_cpus[NR_CPUS];
 	int cpu;
 	struct resource r;
+	int mid;
 
 	/* Map the User Timer registers. */
 	memset(&r, 0, sizeof(r));
@@ -502,9 +502,12 @@ static void __init sun4d_init_timers(irqreturn_t (*counter_fn)(int, void *, stru
 	
 	/* Enable user timer free run for CPU 0 in BW */
 	/* bw_set_ctrl(0, bw_get_ctrl(0) | BW_CTRL_USER_TIMER); */
-    
-	for(cpu = 0; cpu < linux_num_cpus; cpu++)
-		sun4d_load_profile_irq((linux_cpus[cpu].mid >> 3), 0);
+
+	cpu = 0;
+	while (!cpu_find_by_instance(cpu, NULL, &mid)) {
+		sun4d_load_profile_irq(mid >> 3, 0);
+		cpu++;
+	}
 		
 #ifdef CONFIG_SMP
 	{

arch/sparc/kernel/sun4d_smp.c

@@ -18,6 +18,7 @@
 #include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/mm.h>
+#include <linux/swap.h>
 
 #include <asm/ptrace.h>
 #include <asm/atomic.h>
@@ -31,6 +32,9 @@
 #include <asm/hardirq.h>
 #include <asm/sbus.h>
 #include <asm/sbi.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+#include <asm/cpudata.h>
 
 #define __KERNEL_SYSCALLS__
 #include <linux/unistd.h>
@@ -38,7 +42,6 @@
 #define IRQ_CROSS_CALL		15
 
 extern ctxd_t *srmmu_ctx_table_phys;
-extern int linux_num_cpus;
 
 extern void calibrate_delay(void);
 
@@ -47,9 +50,7 @@ extern unsigned long cpu_present_map;
 extern int smp_num_cpus;
 static int smp_highest_cpu;
 extern int smp_threads_ready;
-extern unsigned char mid_xlate[NR_CPUS];
 extern volatile unsigned long cpu_callin_map[NR_CPUS];
-extern unsigned long smp_proc_in_lock[NR_CPUS];
 extern struct cpuinfo_sparc cpu_data[NR_CPUS];
 extern unsigned long cpu_offset[NR_CPUS];
 extern unsigned char boot_cpu_id;
@@ -161,7 +162,6 @@ extern int start_secondary(void *unused);
  *	Cycle through the processors asking the PROM to start each one.
  */
  
-extern struct prom_cpuinfo linux_cpus[NR_CPUS];
 extern struct linux_prom_registers smp_penguin_ctable;
 extern unsigned long trapbase_cpu1[];
 extern unsigned long trapbase_cpu2[];
@@ -170,34 +170,34 @@ extern unsigned long trapbase_cpu3[];
 void __init smp4d_boot_cpus(void)
 {
 	int cpucount = 0;
-	int i = 0;
+	int i, mid;
 
 	printk("Entering SMP Mode...\n");
 	
 	for (i = 0; i < NR_CPUS; i++)
-		cpu_offset[i] = (char *)&cpu_data[i] - (char *)&cpu_data;
+		cpu_offset[i] = (char *)&(cpu_data(i)) - (char *)&(cpu_data(0));
 		
 	if (boot_cpu_id)
 		current_set[0] = NULL;
 
 	local_irq_enable();
 	cpu_present_map = 0;
-	for(i=0; i < linux_num_cpus; i++)
-		cpu_present_map |= (1<<linux_cpus[i].mid);
+
+	/* XXX This whole thing has to go.  See sparc64. */
+	for (i = 0; !cpu_find_by_instance(i, NULL, &mid); i++)
+		cpu_present_map |= (1<<mid);
 	SMP_PRINTK(("cpu_present_map %08lx\n", cpu_present_map));
 	for(i=0; i < NR_CPUS; i++)
 		__cpu_number_map[i] = -1;
 	for(i=0; i < NR_CPUS; i++)
 		__cpu_logical_map[i] = -1;
-	for(i=0; i < NR_CPUS; i++)
-		mid_xlate[i] = i;
 	__cpu_number_map[boot_cpu_id] = 0;
 	__cpu_logical_map[0] = boot_cpu_id;
-	current->cpu = boot_cpu_id;
+	current_thread_info()->cpu = boot_cpu_id;
 	smp_store_cpu_info(boot_cpu_id);
 	smp_setup_percpu_timer();
 	local_flush_cache_all();
-	if(linux_num_cpus == 1)
+	if (cpu_find_by_instance(1, NULL, NULL))
 		return;  /* Not an MP box. */
 	SMP_PRINTK(("Iterating over CPUs\n"));
 	for(i = 0; i < NR_CPUS; i++) {
@@ -218,15 +218,14 @@ void __init smp4d_boot_cpus(void)
 
 			p = prev_task(&init_task);
 
-			p->cpu = i;
+			init_idle(p, i);
 
-			current_set[i] = p;
+			current_set[i] = p->thread_info;
 
 			unhash_process(p);
 
-			for (no = 0; no < linux_num_cpus; no++)
-				if (linux_cpus[no].mid == i)
-					break;
+			for (no = 0; !cpu_find_by_instance(no, NULL, &mid)
+				     && mid != i; no++) ;
 
 			/*
 			 * Initialize the contexts table
@@ -238,9 +237,9 @@ void __init smp4d_boot_cpus(void)
 			smp_penguin_ctable.reg_size = 0;
 
 			/* whirrr, whirrr, whirrrrrrrrr... */
-			SMP_PRINTK(("Starting CPU %d at %p task %d node %08x\n", i, entry, cpucount, linux_cpus[no].prom_node));
+			SMP_PRINTK(("Starting CPU %d at %p task %d node %08x\n", i, entry, cpucount, cpu_data(no).prom_node));
 			local_flush_cache_all();
-			prom_startcpu(linux_cpus[no].prom_node,
+			prom_startcpu(cpu_data(no).prom_node,
 				      &smp_penguin_ctable, 0, (char *)entry);
 				      
 			SMP_PRINTK(("prom_startcpu returned :)\n"));
@@ -275,7 +274,7 @@ void __init smp4d_boot_cpus(void)
 		
 		for(i = 0; i < NR_CPUS; i++) {
 			if(cpu_present_map & (1 << i)) {
-				bogosum += cpu_data[i].udelay_val;
+				bogosum += cpu_data(i).udelay_val;
 				smp_highest_cpu = i;
 			}
 		}
@@ -337,12 +336,12 @@ void smp4d_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
 
 		{
 			/* If you make changes here, make sure gcc generates proper code... */
-			smpfunc_t f asm("i0") = func;
-			unsigned long a1 asm("i1") = arg1;
-			unsigned long a2 asm("i2") = arg2;
-			unsigned long a3 asm("i3") = arg3;
-			unsigned long a4 asm("i4") = arg4;
-			unsigned long a5 asm("i5") = arg5;
+			register smpfunc_t f asm("i0") = func;
+			register unsigned long a1 asm("i1") = arg1;
+			register unsigned long a2 asm("i2") = arg2;
+			register unsigned long a3 asm("i3") = arg3;
+			register unsigned long a4 asm("i4") = arg4;
+			register unsigned long a5 asm("i5") = arg5;
 
 			__asm__ __volatile__(
 				"std %0, [%6]\n\t"
@@ -429,11 +428,11 @@ void smp4d_message_pass(int target, int msg, unsigned long data, int wait)
 	panic("Bogon SMP message pass.");
 }
 
-extern unsigned int prof_multiplier[NR_CPUS];
-extern unsigned int prof_counter[NR_CPUS];
-
 extern void sparc_do_profile(unsigned long pc, unsigned long o7);
 
+#define prof_multiplier(__cpu)		cpu_data(__cpu).multiplier
+#define prof_counter(__cpu)		cpu_data(__cpu).counter
+
 void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
 {
 	int cpu = hard_smp4d_processor_id();
@@ -454,14 +453,14 @@ void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
 	if(!user_mode(regs))
 		sparc_do_profile(regs->pc, regs->u_regs[UREG_RETPC]);
 
-	if(!--prof_counter[cpu]) {
+	if(!--prof_counter(cpu)) {
 		int user = user_mode(regs);
 
 		irq_enter();
 		update_process_times(user);
 		irq_exit();
 
-		prof_counter[cpu] = prof_multiplier[cpu];
+		prof_counter(cpu) = prof_multiplier(cpu);
 	}
 }
 
@@ -471,7 +470,7 @@ static void __init smp_setup_percpu_timer(void)
 {
 	int cpu = hard_smp4d_processor_id();
 
-	prof_counter[cpu] = prof_multiplier[cpu] = 1;
+	prof_counter(cpu) = prof_multiplier(cpu) = 1;
 	load_profile_irq(cpu, lvl14_resolution);
 }
 

arch/sparc/kernel/sun4m_irq.c

@@ -292,8 +292,8 @@ static void __init sun4m_init_timers(irqreturn_t (*counter_fn)(int, void *, stru
 		prom_printf("time_init: unable to attach IRQ%d\n",TIMER_IRQ);
 		prom_halt();
 	}
-    
-	if(linux_num_cpus > 1) {
+   
+	if (!cpu_find_by_instance(1, NULL, NULL)) {
 		for(cpu = 0; cpu < 4; cpu++)
 			sun4m_timers->cpu_timers[cpu].l14_timer_limit = 0;
 		sun4m_interrupts->set = SUN4M_INT_E14;
@@ -327,6 +327,7 @@ void __init sun4m_init_IRQ(void)
 	struct linux_prom_registers int_regs[PROMREG_MAX];
 	int num_regs;
 	struct resource r;
+	int mid;
     
 	local_irq_disable();
 	if((ie_node = prom_searchsiblings(prom_getchild(prom_root_node), "obio")) == 0 ||
@@ -364,10 +365,10 @@ void __init sun4m_init_IRQ(void)
 	sbus_ioremap(&r, 0, int_regs[4].reg_size, "interrupts_system");
 
 	sun4m_interrupts->set = ~SUN4M_INT_MASKALL;
-	for (i=0; i<linux_num_cpus; i++)
-		sun4m_interrupts->cpu_intregs[i].clear = ~0x17fff;
-    
-	if (linux_num_cpus > 1) {
+	for (i = 0; !cpu_find_by_instance(i, NULL, &mid); i++)
+		sun4m_interrupts->cpu_intregs[mid].clear = ~0x17fff;
+
+	if (!cpu_find_by_instance(1, NULL, NULL)) {
 		/* system wide interrupts go to cpu 0, this should always
 		 * be safe because it is guaranteed to be fitted or OBP doesn't
 		 * come up

arch/sparc/kernel/sun4m_smp.c

@@ -15,6 +15,9 @@
 #include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/mm.h>
+#include <linux/swap.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
 
 #include <asm/ptrace.h>
 #include <asm/atomic.h>
@@ -26,6 +29,7 @@
 #include <asm/pgtable.h>
 #include <asm/oplib.h>
 #include <asm/hardirq.h>
+#include <asm/cpudata.h>
 
 #define __KERNEL_SYSCALLS__
 #include <linux/unistd.h>
@@ -35,7 +39,6 @@
 #define IRQ_CROSS_CALL		15
 
 extern ctxd_t *srmmu_ctx_table_phys;
-extern int linux_num_cpus;
 
 extern void calibrate_delay(void);
 
@@ -43,10 +46,7 @@ extern volatile int smp_processors_ready;
 extern unsigned long cpu_present_map;
 extern int smp_num_cpus;
 extern int smp_threads_ready;
-extern unsigned char mid_xlate[NR_CPUS];
 extern volatile unsigned long cpu_callin_map[NR_CPUS];
-extern unsigned long smp_proc_in_lock[NR_CPUS];
-extern struct cpuinfo_sparc cpu_data[NR_CPUS];
 extern unsigned long cpu_offset[NR_CPUS];
 extern unsigned char boot_cpu_id;
 extern int smp_activated;
@@ -83,7 +83,7 @@ void __init smp4m_callin(void)
 	local_flush_cache_all();
 	local_flush_tlb_all();
 
-	set_irq_udt(mid_xlate[boot_cpu_id]);
+	set_irq_udt(boot_cpu_id);
 
 	/* Get our local ticker going. */
 	smp_setup_percpu_timer();
@@ -137,7 +137,6 @@ extern int start_secondary(void *unused);
  *	Cycle through the processors asking the PROM to start each one.
  */
  
-extern struct prom_cpuinfo linux_cpus[NR_CPUS];
 extern struct linux_prom_registers smp_penguin_ctable;
 extern unsigned long trapbase_cpu1[];
 extern unsigned long trapbase_cpu2[];
@@ -146,33 +145,32 @@ extern unsigned long trapbase_cpu3[];
 void __init smp4m_boot_cpus(void)
 {
 	int cpucount = 0;
-	int i = 0;
-	int first, prev;
+	int i, mid;
 
 	printk("Entering SMP Mode...\n");
 
 	local_irq_enable();
 	cpu_present_map = 0;
 
-	for(i=0; i < linux_num_cpus; i++)
-		cpu_present_map |= (1<<i);
+	for (i = 0; !cpu_find_by_instance(i, NULL, &mid); i++)
+		cpu_present_map |= (1<<mid);
 
+	/* XXX cpu_offset is broken -Keith */
 	for(i=0; i < NR_CPUS; i++) {
-		cpu_offset[i] = (char *)&cpu_data[i] - (char *)&cpu_data;
+		cpu_offset[i] = (char *)&(cpu_data(i)) - (char *)&(cpu_data(0));
 		__cpu_number_map[i] = -1;
 		__cpu_logical_map[i] = -1;
 	}
 
-	mid_xlate[boot_cpu_id] = (linux_cpus[boot_cpu_id].mid & ~8);
 	__cpu_number_map[boot_cpu_id] = 0;
 	__cpu_logical_map[0] = boot_cpu_id;
-	current->cpu = boot_cpu_id;
+	current_thread_info()->cpu = boot_cpu_id;
 
 	smp_store_cpu_info(boot_cpu_id);
-	set_irq_udt(mid_xlate[boot_cpu_id]);
+	set_irq_udt(boot_cpu_id);
 	smp_setup_percpu_timer();
 	local_flush_cache_all();
-	if(linux_num_cpus == 1)
+	if(cpu_find_by_instance(1, NULL, NULL))
 		return;  /* Not an MP box. */
 	for(i = 0; i < NR_CPUS; i++) {
 		if(i == boot_cpu_id)
@@ -191,9 +189,9 @@ void __init smp4m_boot_cpus(void)
 
 			p = prev_task(&init_task);
 
-			p->cpu = i;
+			init_idle(p, i);
 
-			current_set[i] = p;
+			current_set[i] = p->thread_info;
 
 			unhash_process(p);
 
@@ -211,9 +209,8 @@ void __init smp4m_boot_cpus(void)
 
 			/* whirrr, whirrr, whirrrrrrrrr... */
 			printk("Starting CPU %d at %p\n", i, entry);
-			mid_xlate[i] = (linux_cpus[i].mid & ~8);
 			local_flush_cache_all();
-			prom_startcpu(linux_cpus[i].prom_node,
+			prom_startcpu(cpu_data(i).prom_node,
 				      &smp_penguin_ctable, 0, (char *)entry);
 
 			/* wheee... it's going... */
@@ -244,7 +241,7 @@ void __init smp4m_boot_cpus(void)
 		unsigned long bogosum = 0;
 		for(i = 0; i < NR_CPUS; i++) {
 			if(cpu_present_map & (1 << i))
-				bogosum += cpu_data[i].udelay_val;
+				bogosum += cpu_data(i).udelay_val;
 		}
 		printk("Total of %d Processors activated (%lu.%02lu BogoMIPS).\n",
 		       cpucount + 1,
@@ -254,20 +251,6 @@ void __init smp4m_boot_cpus(void)
 		smp_num_cpus = cpucount + 1;
 	}
 
-	/* Setup CPU list for IRQ distribution scheme. */
-	first = prev = -1;
-	for(i = 0; i < NR_CPUS; i++) {
-		if(cpu_present_map & (1 << i)) {
-			if(first == -1)
-				first = i;
-			if(prev != -1)
-				cpu_data[prev].next = i;
-			cpu_data[i].mid = mid_xlate[i];
-			prev = i;
-		}
-	}
-	cpu_data[prev].next = first;
-	
 	/* Free unneeded trap tables */
 	if (!(cpu_present_map & (1 << 1))) {
 		ClearPageReserved(virt_to_page(trapbase_cpu1));
@@ -298,11 +281,11 @@ void __init smp4m_boot_cpus(void)
 /* At each hardware IRQ, we get this called to forward IRQ reception
  * to the next processor.  The caller must disable the IRQ level being
  * serviced globally so that there are no double interrupts received.
+ *
+ * XXX See sparc64 irq.c.
  */
 void smp4m_irq_rotate(int cpu)
 {
-	if(smp_processors_ready)
-		set_irq_udt(cpu_data[cpu_data[cpu].next].mid);
 }
 
 /* Cross calls, in order to work efficiently and atomically do all
@@ -334,10 +317,10 @@ void smp4m_message_pass(int target, int msg, unsigned long data, int wait)
 			mask &= ~(1 << me);
 		for(i = 0; i < 4; i++) {
 			if(mask & (1 << i))
-				set_cpu_int(mid_xlate[i], irq);
+				set_cpu_int(i, irq);
 		}
 	} else {
-		set_cpu_int(mid_xlate[target], irq);
+		set_cpu_int(target, irq);
 	}
 	smp_cpu_in_msg[me]--;
 
@@ -388,7 +371,7 @@ void smp4m_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
 				if(mask & (1 << i)) {
 					ccall_info.processors_in[i] = 0;
 					ccall_info.processors_out[i] = 0;
-					set_cpu_int(mid_xlate[i], IRQ_CROSS_CALL);
+					set_cpu_int(i, IRQ_CROSS_CALL);
 				} else {
 					ccall_info.processors_in[i] = 1;
 					ccall_info.processors_out[i] = 1;
@@ -427,28 +410,28 @@ void smp4m_cross_call_irq(void)
 	ccall_info.processors_out[i] = 1;
 }
 
-extern unsigned int prof_multiplier[NR_CPUS];
-extern unsigned int prof_counter[NR_CPUS];
-
 extern void sparc_do_profile(unsigned long pc, unsigned long o7);
 
+#define prof_multiplier(__cpu)		cpu_data(__cpu).multiplier
+#define prof_counter(__cpu)		cpu_data(__cpu).counter
+
 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 {
 	int cpu = smp_processor_id();
 
-	clear_profile_irq(mid_xlate[cpu]);
+	clear_profile_irq(cpu);
 
 	if(!user_mode(regs))
 		sparc_do_profile(regs->pc, regs->u_regs[UREG_RETPC]);
 
-	if(!--prof_counter[cpu]) {
+	if(!--prof_counter(cpu)) {
 		int user = user_mode(regs);
 
 		irq_enter();
 		update_process_times(user);
 		irq_exit();
 
-		prof_counter[cpu] = prof_multiplier[cpu];
+		prof_counter(cpu) = prof_multiplier(cpu);
 	}
 }
 
@@ -458,8 +441,8 @@ static void __init smp_setup_percpu_timer(void)
 {
 	int cpu = smp_processor_id();
 
-	prof_counter[cpu] = prof_multiplier[cpu] = 1;
-	load_profile_irq(mid_xlate[cpu], lvl14_resolution);
+	prof_counter(cpu) = prof_multiplier(cpu) = 1;
+	load_profile_irq(cpu, lvl14_resolution);
 
 	if(cpu == boot_cpu_id)
 		enable_pil_irq(14);

arch/sparc/mm/srmmu.c

@@ -1222,8 +1222,6 @@ static inline void map_kernel(void)
 /* Paging initialization on the Sparc Reference MMU. */
 extern void sparc_context_init(int);
 
-extern int linux_num_cpus;
-
 void (*poke_srmmu)(void) __initdata = NULL;
 
 extern unsigned long bootmem_init(unsigned long *pages_avail);

include/asm-sparc/asmmacro.h

@@ -24,13 +24,10 @@
 	sethi	%hi(boot_cpu_id), %reg; \
 	ldub	[%reg + %lo(boot_cpu_id)], %reg;
 
-#define GET_PROCESSOR_MID(reg, tmp) \
+#define GET_PROCESSOR_MID(reg) \
 	rd	%tbr, %reg; \
-	sethi	%hi(mid_xlate), %tmp; \
 	srl	%reg, 12, %reg; \
-	or	%tmp, %lo(mid_xlate), %tmp; \
-	and	%reg, 3, %reg; \
-	ldub	[%tmp + %reg], %reg;
+	and	%reg, 3, %reg;
 
 #define GET_PROCESSOR_OFFSET(reg, tmp) \
 	GET_PROCESSOR_ID(reg) \

include/asm-sparc/bugs.h

-/*  $Id: bugs.h,v 1.5 1995/11/25 02:31:18 davem Exp $
+/*  $Id: bugs.h,v 1.1 1996/12/26 13:25:20 davem Exp $
  *  include/asm-sparc/bugs.h:  Sparc probes for various bugs.
  *
- *  Copyright (C) 1994 David S. Miller (davem@caip.rutgers.edu)
+ *  Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  */
 
-static void check_bugs(void) { }
+#include <asm/cpudata.h>
+#include <linux/config.h>
+
+extern unsigned long loops_per_jiffy;
+
+static void check_bugs(void)
+{
+#ifndef CONFIG_SMP
+	cpu_data(0).udelay_val = loops_per_jiffy;
+#endif
+}

include/asm-sparc/oplib.h

@@ -306,6 +306,11 @@ extern void prom_apply_obio_ranges(struct linux_prom_registers *obioregs, int nr
 extern void prom_apply_generic_ranges(int node, int parent, 
 				      struct linux_prom_registers *sbusregs, int nregs);
 
+/* CPU probing helpers.  */
+int cpu_find_by_instance(int instance, int *prom_node, int *mid);
+int cpu_find_by_mid(int mid, int *prom_node);
+int cpu_get_hwmid(int prom_node);
+
 extern spinlock_t prom_lock;
 
 #endif /* !(__SPARC_OPLIB_H) */

include/asm-sparc/smp.h

@@ -15,17 +15,7 @@
 
 #include <linux/cpumask.h>
 
-/* PROM provided per-processor information we need
- * to start them all up.
- */
-
-struct prom_cpuinfo {
-	int prom_node;
-	int mid;
-};
-extern int linux_num_cpus;	/* number of CPUs probed  */
-
-#endif /* !(__ASSEMBLY__) */
+#endif /* __ASSEMBLY__ */
 
 #ifdef CONFIG_SMP
 
@@ -33,27 +23,18 @@ extern int linux_num_cpus;	/* number of CPUs probed  */
 
 #include <asm/ptrace.h>
 #include <asm/asi.h>
-
-extern struct prom_cpuinfo linux_cpus[NR_CPUS];
-
-/* Per processor Sparc parameters we need. */
-
-struct cpuinfo_sparc {
-	unsigned long udelay_val; /* that's it */
-	unsigned short next;
-	unsigned short mid;
-};
-
-extern struct cpuinfo_sparc cpu_data[NR_CPUS];
-extern unsigned long cpu_offset[NR_CPUS];
+#include <asm/atomic.h>
 
 /*
  *	Private routines/data
  */
  
 extern unsigned char boot_cpu_id;
-extern unsigned long cpu_present_map;
-#define cpu_online_map cpu_present_map
+extern cpumask_t phys_cpu_present_map;
+#define cpu_possible_map phys_cpu_present_map
+
+extern atomic_t sparc_num_cpus_possible;
+#define num_possible_cpus()	(atomic_read(&sparc_num_cpus_possible))
 
 typedef void (*smpfunc_t)(unsigned long, unsigned long, unsigned long,
 		       unsigned long, unsigned long);
@@ -70,7 +51,7 @@ void smp_boot_cpus(void);
 void smp_store_cpu_info(int);
 
 struct seq_file;
-void smp_bogo_info(struct seq_file *);
+void smp_bogo(struct seq_file *);
 void smp_info(struct seq_file *);
 
 BTFIXUPDEF_CALL(void, smp_cross_call, smpfunc_t, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long)
@@ -105,7 +86,6 @@ extern __inline__ int smp_call_function(void (*func)(void *info), void *info, in
 
 extern __volatile__ int __cpu_number_map[NR_CPUS];
 extern __volatile__ int __cpu_logical_map[NR_CPUS];
-extern unsigned long smp_proc_in_lock[NR_CPUS];
 
 extern __inline__ int cpu_logical_map(int cpu)
 {
@@ -189,7 +169,11 @@ extern __inline__ int hard_smp_processor_id(void)
 #define MBOX_IDLECPU2         0xFD
 #define MBOX_STOPCPU2         0xFE
 
-#endif /* !(CONFIG_SMP) */
+#else /* SMP */
+
+#define num_possible_cpus()	(1)
+
+#endif /* SMP */
 
 #define NO_PROC_ID            0xFF