Subject: Cell: add support for the two additional temperature sensors

The temperature can be read from /sys/devices/system/cpu/cpuX/temperatureX.
The file temperature0 is belonging to the sensor near the linear thermal 
diode on the PPE, temperature1 is the other sensor.

Signed-off-by: Christian Krafft <krafft@de.ibm.com>

Index: linux-2.6/arch/powerpc/platforms/cell/thermal.c
===================================================================
--- linux-2.6.orig/arch/powerpc/platforms/cell/thermal.c
+++ linux-2.6/arch/powerpc/platforms/cell/thermal.c
@@ -23,6 +23,7 @@
 #include <linux/module.h>
 #include <linux/sysdev.h>
 #include <linux/kernel.h>
+#include <linux/cpu.h>
 #include <asm/spu.h>
 #include <asm/io.h>
 #include <asm/prom.h>
@@ -54,17 +55,74 @@ static ssize_t spu_show_temp(struct sys_
 
 	return sprintf(buf, "%d\n", (int) value);
 }
-static SYSDEV_ATTR(temperature, 0400, spu_show_temp, NULL);
+
+static ssize_t ppe_show_temp(struct sys_device *sysdev, char *buf, int pos)
+{
+	struct cbe_pmd_regs *pmd_regs;
+	u64 value;
+
+	pmd_regs = cbe_get_cpu_pmd_regs(sysdev->id);
+	value = in_be64(&pmd_regs->ts_ctsr2);
+
+	/* access the corresponding byte */
+	value >>= pos;
+	/* clear all other bits */
+	value &= 0x3F;
+	/* temp is stored in steps of 2 degrees */
+	value *= 2;
+	/* base temp is 65 degrees */
+	value += 65;
+
+	return sprintf(buf, "%d\n", (int) value);
+}
+
+
+/* shows the temperature of the DTS on the PPE,
+ * located near the linear thermal sensor */
+static ssize_t ppe_show_temp0(struct sys_device *sysdev, char *buf)
+{
+	return ppe_show_temp(sysdev, buf, 32);
+}
+
+/* shows the temperature of the second DTS on the PPE */
+static ssize_t ppe_show_temp1(struct sys_device *sysdev, char *buf)
+{
+	return ppe_show_temp(sysdev, buf, 0);
+}
+
+static struct sysdev_attribute attr_spu_temperature = {
+	.attr = {.name = "temperature", .mode = 0400 },
+	.show = spu_show_temp,
+	.store = NULL,
+};
+
+static struct sysdev_attribute attr_ppe_temperature0 = {
+	.attr = {.name = "temperature0", .mode = 0400 },
+	.show = ppe_show_temp0,
+	.store = NULL,
+};
+
+
+static struct sysdev_attribute attr_ppe_temperature1 = {
+	.attr = {.name = "temperature1", .mode = 0400 },
+	.show = ppe_show_temp1,
+	.store = NULL,
+};
 
 static int __init thermal_init(void)
 {
-	return spu_add_sysdev_attr(&attr_temperature);
+	spu_add_sysdev_attr(&attr_spu_temperature);
+	cpu_add_sysdev_attr(&attr_ppe_temperature0);
+	cpu_add_sysdev_attr(&attr_ppe_temperature1);
+	return 0;
 }
 module_init(thermal_init);
 
 static void __exit thermal_exit(void)
 {
-	spu_remove_sysdev_attr(&attr_temperature);
+	spu_remove_sysdev_attr(&attr_spu_temperature);
+	cpu_remove_sysdev_attr(&attr_ppe_temperature0);
+	cpu_remove_sysdev_attr(&attr_ppe_temperature1);
 }
 module_exit(thermal_exit);
 
Index: linux-2.6/include/linux/cpu.h
===================================================================
--- linux-2.6.orig/include/linux/cpu.h
+++ linux-2.6/include/linux/cpu.h
@@ -33,6 +33,10 @@ struct cpu {
 
 extern int register_cpu(struct cpu *cpu, int num);
 extern struct sys_device *get_cpu_sysdev(unsigned cpu);
+
+extern int cpu_add_sysdev_attr(struct sysdev_attribute *attr);
+extern void cpu_remove_sysdev_attr(struct sysdev_attribute *attr);
+
 #ifdef CONFIG_HOTPLUG_CPU
 extern void unregister_cpu(struct cpu *cpu);
 #endif
Index: linux-2.6/arch/powerpc/kernel/sysfs.c
===================================================================
--- linux-2.6.orig/arch/powerpc/kernel/sysfs.c
+++ linux-2.6/arch/powerpc/kernel/sysfs.c
@@ -300,6 +300,37 @@ static struct notifier_block __devinitda
 	.notifier_call	= sysfs_cpu_notify,
 };
 
+static DEFINE_MUTEX(cpu_mutex);
+
+int cpu_add_sysdev_attr(struct sysdev_attribute *attr)
+{
+	int cpu;
+
+	mutex_lock(&cpu_mutex);
+
+	for_each_possible_cpu(cpu) {
+		sysdev_create_file(get_cpu_sysdev(cpu), attr);
+	}
+
+	mutex_unlock(&cpu_mutex);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr);
+
+void cpu_remove_sysdev_attr(struct sysdev_attribute *attr)
+{
+	int cpu;
+
+	mutex_lock(&cpu_mutex);
+
+	for_each_possible_cpu(cpu) {
+		sysdev_remove_file(get_cpu_sysdev(cpu), attr);
+	}
+
+	mutex_unlock(&cpu_mutex);
+}
+EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr);
+
 /* NUMA stuff */
 
 #ifdef CONFIG_NUMA