Subject: Re: [PATCH]Enabling Auto poweron after power is restored.

From: Manish Ahuja <[email-masked]>
Date: Sun, 24 Dec 2006 11:50:58 -0600

During power outages, the ups notifies the system for a shutdown. In the 
current setup, it isn't possible to power on when power is restored. 
This patch fixes the issue by calling the right ibm,power-off-ups token 
during such events. It also adds a proc interface so that rc.powerfail 
can parse the epow events and modify the power-off behavior accordingly 
to enable the right token to be called.

Signed-off-by: Manish Ahuja <[email-masked]>

Index: 2.6-git2/arch/powerpc/kernel/rtas.c
===================================================================
--- 2.6-git2.orig/arch/powerpc/kernel/rtas.c	2006-11-29 12:00:26.000000000 -0800
+++ 2.6-git2/arch/powerpc/kernel/rtas.c	2006-12-24 09:30:01.000000000 -0800
@@ -52,6 +52,7 @@
 EXPORT_SYMBOL(rtas_data_buf);
 
 unsigned long rtas_rmo_buf;
+unsigned long rtas_poweron_auto; /* default and normal state is 0 */
 
 /*
  * If non-NULL, this gets called when the kernel terminates.
@@ -601,14 +602,32 @@
 	for (;;);
 }
 
+/**
+ * rtas_power_off - tell firmware about how to power off the system.
+ *
+ * This function calls either the power-off rtas token in normal cases
+ * or the ibm,power-off-ups token (if present & requested) in case of
+ * a power failure. If power-off token is used, power on will only be
+ * possible with power button press. If ibm,power-off-ups token is used
+ * it will allow auto poweron after power is restored.
+ */
 void rtas_power_off(void)
 {
-	if (rtas_flash_term_hook)
-		rtas_flash_term_hook(SYS_POWER_OFF);
-	/* allow power on only with power button press */
-	printk("RTAS power-off returned %d\n",
-	       rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
-	for (;;);
+	int rc;
+	int rtas_poweroff_ups_token = rtas_token("ibm,power-off-ups");
+
+ 	if (rtas_flash_term_hook)
+ 		rtas_flash_term_hook(SYS_POWER_OFF);
+
+	if (rtas_poweron_auto == 0 ||
+		rtas_poweroff_ups_token == RTAS_UNKNOWN_SERVICE) {
+		rc = rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1);
+		printk(KERN_INFO "RTAS power-off returned %d\n", rc);
+	} else {
+		rc = rtas_call(rtas_poweroff_ups_token, 0, 1, NULL);
+		printk(KERN_INFO "RTAS ibm,power-off-ups returned %d\n", rc);
+	}
+ 	for (;;);
 }
 
 void rtas_halt(void)
Index: 2.6-git2/arch/powerpc/kernel/rtas-proc.c
===================================================================
--- 2.6-git2.orig/arch/powerpc/kernel/rtas-proc.c	2006-11-29 11:51:49.000000000 -0800
+++ 2.6-git2/arch/powerpc/kernel/rtas-proc.c	2006-12-24 09:28:41.000000000 -0800
@@ -154,6 +154,9 @@
 		const char __user *buf, size_t count, loff_t *ppos);
 static int ppc_rtas_tone_volume_show(struct seq_file *m, void *v);
 static int ppc_rtas_rmo_buf_show(struct seq_file *m, void *v);
+static int ppc_rtas_poweron_auto_show(struct seq_file *m, void *v);
+static ssize_t ppc_rtas_poweron_auto_write(struct file *file,
+		const char __user *buf, size_t count, loff_t *ppos);
 
 static int sensors_open(struct inode *inode, struct file *file)
 {
@@ -244,6 +247,18 @@
 	.release	= single_release,
 };
 
+static int poweron_auto_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, ppc_rtas_poweron_auto_show, NULL);
+}
+
+struct file_operations ppc_rtas_poweron_auto_operations = {
+	.open		= poweron_auto_open,
+	.read		= seq_read,
+	.write		= ppc_rtas_poweron_auto_write,
+	.release	= single_release,
+};
+
 static int ppc_rtas_find_all_sensors(void);
 static void ppc_rtas_process_sensor(struct seq_file *m,
 	struct individual_sensor *s, int state, int error, const char *loc);
@@ -293,6 +308,10 @@
 	if (entry)
 		entry->proc_fops = &ppc_rtas_rmo_buf_ops;
 
+	entry = create_proc_entry("ppc64/rtas/poweron_auto", S_IRUGO|S_IWUSR, NULL);
+	if (entry)
+		entry->proc_fops = &ppc_rtas_poweron_auto_operations;
+
 	return 0;
 }
 
@@ -805,3 +824,24 @@
 	seq_printf(m, "%016lx %x\n", rtas_rmo_buf, RTAS_RMOBUF_MAX);
 	return 0;
 }
+
+static ssize_t ppc_rtas_poweron_auto_write(struct file *file,
+		const char __user *buf, size_t count, loff_t *ppos)
+{
+	unsigned long ups_restart;
+	int error = parse_number(buf, count, &ups_restart);
+	if (error)
+		return error;
+
+	if (ups_restart)
+		rtas_poweron_auto = 1;
+
+	return count;
+}
+
+static int ppc_rtas_poweron_auto_show(struct seq_file *m, void *v)
+{
+        seq_printf(m, "%lu\n", rtas_poweron_auto);
+        return 0;
+
+}
Index: 2.6-git2/include/asm-powerpc/rtas.h
===================================================================
--- 2.6-git2.orig/include/asm-powerpc/rtas.h	2006-11-28 14:41:17.000000000 -0800
+++ 2.6-git2/include/asm-powerpc/rtas.h	2006-11-30 10:42:35.000000000 -0800
@@ -228,6 +228,9 @@
 /* RMO buffer reserved for user-space RTAS use */
 extern unsigned long rtas_rmo_buf;
 
+/* Poweron buffer used for enabling auto ups restart */
+extern unsigned long rtas_poweron_auto;
+
 #define GLOBAL_INTERRUPT_QUEUE 9005
 
 /**