powerpc/eeh: Move EEH initialization around

Currently, we have 3 phases for EEH initialization on pSeries platform.
All of them are done through builtin functions: platform initialization,
EEH device creation, and EEH subsystem enablement. All of them are done
no later than ppc_md.setup_arch. That means that the slab/slub isn't ready
yet, so we have to allocate memory chunks on basis of PAGE_SIZE for those
dynamically created EEH devices. That's pretty expensive.

In order to utilize slab/slub for memory allocation, we have to move the EEH
initialization functions around, but all of them should be called after slab
is ready.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/eeh.h

@@ -117,11 +117,6 @@ extern int eeh_subsystem_enabled;
 
 void * __devinit eeh_dev_init(struct device_node *dn, void *data);
 void __devinit eeh_dev_phb_init_dynamic(struct pci_controller *phb);
-void __init eeh_dev_phb_init(void);
-void __init eeh_init(void);
-#ifdef CONFIG_PPC_PSERIES
-int __init eeh_pseries_init(void);
-#endif
 int __init eeh_ops_register(struct eeh_ops *ops);
 int __exit eeh_ops_unregister(const char *name);
 unsigned long eeh_check_failure(const volatile void __iomem *token,
@@ -156,17 +151,6 @@ static inline void *eeh_dev_init(struct device_node *dn, void *data)
 
 static inline void eeh_dev_phb_init_dynamic(struct pci_controller *phb) { }
 
-static inline void eeh_dev_phb_init(void) { }
-
-static inline void eeh_init(void) { }
-
-#ifdef CONFIG_PPC_PSERIES
-static inline int eeh_pseries_init(void)
-{
-	return 0;
-}
-#endif /* CONFIG_PPC_PSERIES */
-
 static inline unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned long val)
 {
 	return val;

arch/powerpc/kernel/rtas_pci.c

@@ -275,9 +275,6 @@ void __init find_and_init_phbs(void)
 	of_node_put(root);
 	pci_devs_phb_init();
 
-	/* Create EEH devices for all PHBs */
-	eeh_dev_phb_init();
-
 	/*
 	 * PCI_PROBE_ONLY and PCI_REASSIGN_ALL_BUS can be set via properties
 	 * in chosen.

arch/powerpc/platforms/pseries/eeh.c

@@ -982,7 +982,7 @@ int __exit eeh_ops_unregister(const char *name)
  * Even if force-off is set, the EEH hardware is still enabled, so that
  * newer systems can boot.
  */
-void __init eeh_init(void)
+static int __init eeh_init(void)
 {
 	struct pci_controller *hose, *tmp;
 	struct device_node *phb;
@@ -992,11 +992,11 @@ void __init eeh_init(void)
 	if (!eeh_ops) {
 		pr_warning("%s: Platform EEH operation not found\n",
 			__func__);
-		return;
+		return -EEXIST;
 	} else if ((ret = eeh_ops->init())) {
 		pr_warning("%s: Failed to call platform init function (%d)\n",
 			__func__, ret);
-		return;
+		return ret;
 	}
 
 	raw_spin_lock_init(&confirm_error_lock);
@@ -1011,8 +1011,12 @@ void __init eeh_init(void)
 		printk(KERN_INFO "EEH: PCI Enhanced I/O Error Handling Enabled\n");
 	else
 		printk(KERN_WARNING "EEH: No capable adapters found\n");
+
+	return ret;
 }
 
+core_initcall_sync(eeh_init);
+
 /**
  * eeh_add_device_early - Enable EEH for the indicated device_node
  * @dn: device node for which to set up EEH

arch/powerpc/platforms/pseries/eeh_dev.c

@@ -93,10 +93,14 @@ void __devinit eeh_dev_phb_init_dynamic(struct pci_controller *phb)
  * Scan all the existing PHBs and create EEH devices for their OF
  * nodes and their children OF nodes
  */
-void __init eeh_dev_phb_init(void)
+static int __init eeh_dev_phb_init(void)
 {
 	struct pci_controller *phb, *tmp;
 
 	list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
 		eeh_dev_phb_init_dynamic(phb);
+
+	return 0;
 }
+
+core_initcall(eeh_dev_phb_init);

arch/powerpc/platforms/pseries/eeh_pseries.c

@@ -559,7 +559,9 @@ static struct eeh_ops pseries_eeh_ops = {
  * EEH initialization on pseries platform. This function should be
  * called before any EEH related functions.
  */
-int __init eeh_pseries_init(void)
+static int __init eeh_pseries_init(void)
 {
 	return eeh_ops_register(&pseries_eeh_ops);
 }
+
+early_initcall(eeh_pseries_init);

arch/powerpc/platforms/pseries/setup.c

@@ -388,10 +388,8 @@ static void __init pSeries_setup_arch(void)
 
 	/* Find and initialize PCI host bridges */
 	init_pci_config_tokens();
-	eeh_pseries_init();
 	find_and_init_phbs();
 	pSeries_reconfig_notifier_register(&pci_dn_reconfig_nb);
-	eeh_init();
 
 	pSeries_nvram_init();