Commit 395ee2a2 authored by Oliver O'Halloran's avatar Oliver O'Halloran Committed by Michael Ellerman
Browse files

powerpc/eeh: Move EEH initialisation to an arch initcall 



The initialisation of EEH mostly happens in a core_initcall_sync initcall,
followed by registering a bus notifier later on in an arch_initcall.
Anything involving initcall dependecies is mostly incomprehensible unless
you've spent a while staring at code so here's the full sequence:

ppc_md.setup_arch       <-- pci_controllers are created here

...time passes...

core_initcall           <-- pci_dns are created from DT nodes
core_initcall_sync      <-- platforms call eeh_init()
postcore_initcall       <-- PCI bus type is registered
postcore_initcall_sync
arch_initcall           <-- EEH pci_bus notifier registered
subsys_initcall         <-- PHBs are scanned here

There's no real requirement to do the EEH setup at the core_initcall_sync
level. It just needs to be done after pci_dn's are created and before we
start scanning PHBs. Simplify the flow a bit by moving the platform EEH
inititalisation to an arch_initcall so we can fold the bus notifier
registration into eeh_init().

Signed-off-by: default avatarOliver O'Halloran <oohall@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200918093050.37344-5-oohall@gmail.com
parent 5d69e46a

arch/powerpc/kernel/eeh.c

+32 −32
Original line number Diff line number Diff line
@@ -940,6 +940,30 @@ static struct notifier_block eeh_reboot_nb = { 
	.notifier_call = eeh_reboot_notifier,

};



static int eeh_device_notifier(struct notifier_block *nb,

			       unsigned long action, void *data)

{

	struct device *dev = data;



	switch (action) {

	/*

	 * Note: It's not possible to perform EEH device addition (i.e.

	 * {pseries,pnv}_pcibios_bus_add_device()) here because it depends on

	 * the device's resources, which have not yet been set up.

	 */

	case BUS_NOTIFY_DEL_DEVICE:

		eeh_remove_device(to_pci_dev(dev));

		break;

	default:

		break;

	}

	return NOTIFY_DONE;

}



static struct notifier_block eeh_device_nb = {

	.notifier_call = eeh_device_notifier,

};



/**

 * eeh_init - System wide EEH initialization

 *
@@ -960,7 +984,14 @@ int eeh_init(struct eeh_ops *ops) 
	/* Register reboot notifier */

	ret = register_reboot_notifier(&eeh_reboot_nb);

	if (ret) {

		pr_warn("%s: Failed to register notifier (%d)\n",

		pr_warn("%s: Failed to register reboot notifier (%d)\n",

			__func__, ret);

		return ret;

	}



	ret = bus_register_notifier(&pci_bus_type, &eeh_device_nb);

	if (ret) {

		pr_warn("%s: Failed to register bus notifier (%d)\n",

			__func__, ret);

		return ret;

	}
@@ -975,37 +1006,6 @@ int eeh_init(struct eeh_ops *ops) 
	return eeh_event_init();

}



static int eeh_device_notifier(struct notifier_block *nb,

			       unsigned long action, void *data)

{

	struct device *dev = data;



	switch (action) {

	/*

	 * Note: It's not possible to perform EEH device addition (i.e.

	 * {pseries,pnv}_pcibios_bus_add_device()) here because it depends on

	 * the device's resources, which have not yet been set up.

	 */

	case BUS_NOTIFY_DEL_DEVICE:

		eeh_remove_device(to_pci_dev(dev));

		break;

	default:

		break;

	}

	return NOTIFY_DONE;

}



static struct notifier_block eeh_device_nb = {

	.notifier_call = eeh_device_notifier,

};



static __init int eeh_set_bus_notifier(void)

{

	bus_register_notifier(&pci_bus_type, &eeh_device_nb);

	return 0;

}

arch_initcall(eeh_set_bus_notifier);



/**

 * eeh_probe_device() - Perform EEH initialization for the indicated pci device

 * @dev: pci device for which to set up EEH

arch/powerpc/platforms/powernv/eeh-powernv.c

+1 −1
Original line number Diff line number Diff line
@@ -1721,4 +1721,4 @@ static int __init eeh_powernv_init(void) 


	return ret;

}

machine_core_initcall_sync(powernv, eeh_powernv_init);
 
machine_arch_initcall(powernv, eeh_powernv_init);

arch/powerpc/platforms/pseries/eeh_pseries.c

+1 −1
Original line number Diff line number Diff line
@@ -985,4 +985,4 @@ static int __init eeh_pseries_init(void) 
			ret);

	return ret;

}

machine_core_initcall_sync(pseries, eeh_pseries_init);
 
machine_arch_initcall(pseries, eeh_pseries_init);

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