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Commit 7441b062 authored by Jan Glauber's avatar Jan Glauber Committed by Martin Schwidefsky
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s390/pci: PCI hotplug support via SCLP 



Add SCLP PCI configure/deconfigure and implement a PCI hotplug
controller (s390_pci_hpc). The hotplug controller creates a slot
for every PCI function in stand-by or configured state. The PCI
functions are named after the PCI function ID (fid). By writing to
the power attribute in /sys/bus/pci/slots/<fid>/power the PCI function
is moved to stand-by or configured state. If moved to the configured
state the device is automatically scanned by the s390 PCI layer.

Signed-off-by: default avatarJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent cbc0dd1f

arch/s390/include/asm/pci.h

+11 −0
Original line number Diff line number Diff line
@@ -95,6 +95,11 @@ struct zpci_dev { 
	enum pci_bus_speed max_bus_speed;

};



struct pci_hp_callback_ops {

	int (*create_slot)	(struct zpci_dev *zdev);

	void (*remove_slot)	(struct zpci_dev *zdev);

};



static inline bool zdev_enabled(struct zpci_dev *zdev)

{

	return (zdev->fh & (1UL << 31)) ? true : false;
@@ -140,4 +145,10 @@ bool zpci_fid_present(u32); 
int zpci_dma_init(void);

void zpci_dma_exit(void);



/* Hotplug */

extern struct mutex zpci_list_lock;

extern struct list_head zpci_list;

extern struct pci_hp_callback_ops hotplug_ops;

extern unsigned int pci_probe;



#endif

arch/s390/include/asm/sclp.h

+2 −0
Original line number Diff line number Diff line
@@ -55,5 +55,7 @@ int sclp_chp_read_info(struct sclp_chp_info *info); 
void sclp_get_ipl_info(struct sclp_ipl_info *info);

bool sclp_has_linemode(void);

bool sclp_has_vt220(void);

int sclp_pci_configure(u32 fid);

int sclp_pci_deconfigure(u32 fid);



#endif /* _ASM_S390_SCLP_H */

arch/s390/pci/pci.c

+9 −0
Original line number Diff line number Diff line
@@ -47,7 +47,12 @@ 


/* list of all detected zpci devices */

LIST_HEAD(zpci_list);

EXPORT_SYMBOL_GPL(zpci_list);

DEFINE_MUTEX(zpci_list_lock);

EXPORT_SYMBOL_GPL(zpci_list_lock);



struct pci_hp_callback_ops hotplug_ops;

EXPORT_SYMBOL_GPL(hotplug_ops);



static DECLARE_BITMAP(zpci_domain, ZPCI_NR_DEVICES);

static DEFINE_SPINLOCK(zpci_domain_lock);
@@ -935,6 +940,8 @@ int zpci_create_device(struct zpci_dev *zdev) 


	mutex_lock(&zpci_list_lock);

	list_add_tail(&zdev->entry, &zpci_list);

	if (hotplug_ops.create_slot)

		hotplug_ops.create_slot(zdev);

	mutex_unlock(&zpci_list_lock);



	if (zdev->state == ZPCI_FN_STATE_STANDBY)
@@ -948,6 +955,8 @@ int zpci_create_device(struct zpci_dev *zdev) 
out_start:

	mutex_lock(&zpci_list_lock);

	list_del(&zdev->entry);

	if (hotplug_ops.remove_slot)

		hotplug_ops.remove_slot(zdev);

	mutex_unlock(&zpci_list_lock);

out_bus:

	zpci_free_domain(zdev);

drivers/pci/hotplug/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -151,4 +151,15 @@ config HOTPLUG_PCI_SGI 


	  When in doubt, say N.



config HOTPLUG_PCI_S390

	tristate "System z PCI Hotplug Support"

	depends on S390 && 64BIT

	help

	  Say Y here if you want to use the System z PCI Hotplug

	  driver for PCI devices. Without this driver it is not

	  possible to access stand-by PCI functions nor to deconfigure

	  PCI functions.



	  When in doubt, say Y.



endif # HOTPLUG_PCI

drivers/pci/hotplug/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ obj-$(CONFIG_HOTPLUG_PCI_RPA) += rpaphp.o 
obj-$(CONFIG_HOTPLUG_PCI_RPA_DLPAR)	+= rpadlpar_io.o

obj-$(CONFIG_HOTPLUG_PCI_SGI)		+= sgi_hotplug.o

obj-$(CONFIG_HOTPLUG_PCI_ACPI)		+= acpiphp.o

obj-$(CONFIG_HOTPLUG_PCI_S390)		+= s390_pci_hpc.o



# acpiphp_ibm extends acpiphp, so should be linked afterwards.