[PATCH v2 0/8] Introduce logical CPU mapping

@@ -8,6 +8,7 @@
 #define CPUID_CACHETYPE	1
 #define CPUID_TCM	2
 #define CPUID_TLBTYPE	3
+#define CPUID_MPIDR	5
 
 #define CPUID_EXT_PFR0	"c1, 0"
 #define CPUID_EXT_PFR1	"c1, 1"

@@ -70,6 +71,11 @@ static inline unsigned int __attribute_const__ read_cpuid_tcmstatus(void)
 	return read_cpuid(CPUID_TCM);
 }
 
+static inline unsigned int __attribute_const__ read_cpuid_mpidr(void)
+{
+	return read_cpuid(CPUID_MPIDR);
+}
+
 /*
  * Intel's XScale3 core supports some v6 features (supersections, L2)
  * but advertises itself as v5 as it does not support the v6 ISA.  For

@@ -66,6 +66,12 @@ extern void platform_secondary_init(unsigned int cpu);
 extern void platform_smp_prepare_cpus(unsigned int);
 
 /*
+ * Logical CPU mapping.
+ */
+extern int __cpu_logical_map[NR_CPUS];
+#define cpu_logical_map(cpu)	__cpu_logical_map[cpu]
+
+/*
  * Initial data for bringing up a secondary CPU.
  */
 struct secondary_data {

@@ -39,6 +39,7 @@
 #include <asm/tlbflush.h>
 #include <asm/ptrace.h>
 #include <asm/localtimer.h>
+#include <asm/smp_plat.h>
 
 /*
  * as from 2.5, kernels no longer have an init_tasks structure

@@ -259,6 +260,20 @@ void __ref cpu_die(void)
 }
 #endif /* CONFIG_HOTPLUG_CPU */
 
+int __cpu_logical_map[NR_CPUS];
+
+void __init smp_setup_processor_id(void)
+{
+	int i;
+	u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0;
+
+	cpu_logical_map(0) = cpu;
+	for (i = 1; i < NR_CPUS; ++i)
+		cpu_logical_map(i) = i == cpu ? 0 : i;
+
+	printk(KERN_INFO "Booting Linux on physical CPU %d\n", cpu);
+}
+
 /*
  * Called by both boot and secondaries to move global data into
  * per-processor storage.

@@ -180,7 +180,7 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
 		return -EINVAL;
 
 	mask = 0xff << shift;
-	bit = 1 << (cpu + shift);
+	bit = 1 << (cpu_logical_map(cpu) + shift);
 
 	spin_lock(&irq_controller_lock);
 	val = readl_relaxed(reg) & ~mask;

@@ -259,9 +259,15 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
 	unsigned int irq_start)
 {
 	unsigned int gic_irqs, irq_limit, i;
+	u32 cpumask;
 	void __iomem *base = gic->dist_base;
-	u32 cpumask = 1 << smp_processor_id();
+	u32 cpu = 0;
 
+#ifdef CONFIG_SMP
+	cpu = cpu_logical_map(smp_processor_id());
+#endif
+
+	cpumask = 1 << cpu;
 	cpumask |= cpumask << 8;
 	cpumask |= cpumask << 16;
 

@@ -382,7 +388,12 @@ void __cpuinit gic_enable_ppi(unsigned int irq)
 #ifdef CONFIG_SMP
 void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
 {
-	unsigned long map = *cpus_addr(*mask);
+	int cpu;
+	unsigned long map = 0;
+
+	/* Convert our logical CPU mask into a physical one. */
+	for_each_cpu(cpu, mask)
+		map |= 1 << cpu_logical_map(cpu);
 
 	/*
 	 * Ensure that stores to Normal memory are visible to the

@@ -75,7 +75,7 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
 		    :
 		    : "memory", "cc");
 
-		if (pen_release == cpu) {
+		if (pen_release == cpu_logical_map(cpu)) {
 			/*
 			 * OK, proper wakeup, we're done
 			 */

@@ -126,7 +126,7 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
 	 * Note that "pen_release" is the hardware CPU ID, whereas
 	 * "cpu" is Linux's internal ID.
 	 */
-	write_pen_release(cpu);
+	write_pen_release(cpu_logical_map(cpu));
 
 	if (!(__raw_readl(S5P_ARM_CORE1_STATUS) & S5P_CORE_LOCAL_PWR_EN)) {
 		__raw_writel(S5P_CORE_LOCAL_PWR_EN,

@@ -37,7 +37,7 @@ static inline void platform_do_lowpower(unsigned int cpu)
 		    :
 		    : "memory", "cc");
 
-		if (pen_release == cpu) {
+		if (pen_release == cpu_logical_map(cpu)) {
 			/*
 			 * OK, proper wakeup, we're done
 			 */

@@ -117,7 +117,7 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
 	 * Note that "pen_release" is the hardware CPU ID, whereas
 	 * "cpu" is Linux's internal ID.
 	 */
-	pen_release = cpu;
+	pen_release = cpu_logical_map(cpu);
 	__cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
 	outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1));
 

@@ -74,6 +74,8 @@ void __cpuinit sh73a0_secondary_init(unsigned int cpu)
 
 int __cpuinit sh73a0_boot_secondary(unsigned int cpu)
 {
+	cpu = cpu_logical_map(cpu);
+
 	/* enable cache coherency */
 	modify_scu_cpu_psr(0, 3 << (cpu * 8));
 

@@ -87,6 +89,8 @@ int __cpuinit sh73a0_boot_secondary(unsigned int cpu)
 
 void __init sh73a0_smp_prepare_cpus(void)
 {
+	int cpu = cpu_logical_map(0);
+
 	scu_enable(scu_base_addr());
 
 	/* Map the reset vector (in headsmp.S) */

@@ -94,5 +98,5 @@ void __init sh73a0_smp_prepare_cpus(void)
 	__raw_writel(__pa(shmobile_secondary_vector), __io(SBAR));
 
 	/* enable cache coherency on CPU0 */
-	modify_scu_cpu_psr(0, 3 << (0 * 8));
+	modify_scu_cpu_psr(0, 3 << (cpu * 8));
 }

@@ -24,7 +24,7 @@ static inline void platform_do_lowpower(unsigned int cpu)
 	for (;;) {
 		__asm__ __volatile__("dsb\n\t" "wfi\n\t"
 				: : : "memory");
-		if (pen_release == cpu) {
+		if (pen_release == cpu_logical_map(cpu)) {
 			/*
 			 * OK, proper wakeup, we're done
 			 */

@@ -96,7 +96,7 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
 	 * the holding pen - release it, then wait for it to flag
 	 * that it has been released by resetting pen_release.
 	 */
-	write_pen_release(cpu);
+	write_pen_release(cpu_logical_map(cpu));
 
 	gic_raise_softirq(cpumask_of(cpu), 1);
 

@@ -69,7 +69,7 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
 		    :
 		    : "memory", "cc");
 
-		if (pen_release == cpu) {
+		if (pen_release == cpu_logical_map(cpu)) {
 			/*
 			 * OK, proper wakeup, we're done
 			 */

@@ -70,7 +70,7 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
 		    :
 		    : "memory", "cc");
 
-		if (pen_release == cpu) {
+		if (pen_release == cpu_logical_map(cpu)) {
 			/*
 			 * OK, proper wakeup, we're done
 			 */

@@ -77,7 +77,7 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
 	 * since we haven't sent them a soft interrupt, they shouldn't
 	 * be there.
 	 */
-	write_pen_release(cpu);
+	write_pen_release(cpu_logical_map(cpu));
 
 	/*
 	 * Send the secondary CPU a soft interrupt, thereby causing