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: Jan Glauber <jang@xxxxxxxxxxxxxxxxxx>
---
arch/s390/include/asm/pci.h | 11 ++
arch/s390/include/asm/sclp.h | 2 +
arch/s390/pci/pci.c | 9 ++
drivers/pci/hotplug/Kconfig | 11 ++
drivers/pci/hotplug/Makefile | 1 +
drivers/pci/hotplug/s390_pci_hpc.c | 252 +++++++++++++++++++++++++++++++++++++
drivers/s390/char/sclp.h | 3 +-
drivers/s390/char/sclp_cmd.c | 64 +++++++++-
8 files changed, 351 insertions(+), 2 deletions(-)
create mode 100644 drivers/pci/hotplug/s390_pci_hpc.c
diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index 3dc2cb6..739d9f1 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -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
diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index e62a555..8337886 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -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 */
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 5a2ef9e..c523594 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -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);
diff --git a/drivers/pci/hotplug/Kconfig b/drivers/pci/hotplug/Kconfig
index b0e46de..0594c4a 100644
--- a/drivers/pci/hotplug/Kconfig
+++ b/drivers/pci/hotplug/Kconfig
@@ -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
diff --git a/drivers/pci/hotplug/Makefile b/drivers/pci/hotplug/Makefile
index c459cd4..47ec8c8 100644
--- a/drivers/pci/hotplug/Makefile
+++ b/drivers/pci/hotplug/Makefile
@@ -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.
diff --git a/drivers/pci/hotplug/s390_pci_hpc.c b/drivers/pci/hotplug/s390_pci_hpc.c
new file mode 100644
index 0000000..d4de895
--- /dev/null
+++ b/drivers/pci/hotplug/s390_pci_hpc.c
@@ -0,0 +1,252 @@
+/*
+ * PCI Hot Plug Controller Driver for System z
+ *
+ * Copyright 2012 IBM Corp.
+ *
+ * Author(s):
+ * Jan Glauber <jang@xxxxxxxxxxxxxxxxxx>
+ */
+
+#define COMPONENT "zPCI hpc"
+#define pr_fmt(fmt) COMPONENT ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/pci_hotplug.h>
+#include <linux/init.h>
+#include <asm/sclp.h>
+
+#define SLOT_NAME_SIZE 10
+static LIST_HEAD(s390_hotplug_slot_list);
+
+MODULE_AUTHOR("Jan Glauber <jang@xxxxxxxxxxxxxxxxxx");
+MODULE_DESCRIPTION("Hot Plug PCI Controller for System z");
+MODULE_LICENSE("GPL");
+
+static int zpci_fn_configured(enum zpci_state state)
+{
+ return state == ZPCI_FN_STATE_CONFIGURED ||
+ state == ZPCI_FN_STATE_ONLINE;
+}
+
+/*
+ * struct slot - slot information for each *physical* slot
+ */
+struct slot {
+ struct list_head slot_list;
+ struct hotplug_slot *hotplug_slot;
+ struct zpci_dev *zdev;
+};
+
+static int enable_slot(struct hotplug_slot *hotplug_slot)
+{
+ struct slot *slot = hotplug_slot->private;
+ int rc;
+
+ if (slot->zdev->state != ZPCI_FN_STATE_STANDBY)
+ return -EIO;
+
+ rc = sclp_pci_configure(slot->zdev->fid);
+ if (!rc) {
+ slot->zdev->state = ZPCI_FN_STATE_CONFIGURED;
+ /* automatically scan the device after is was configured */
+ zpci_enable_device(slot->zdev);
+ zpci_scan_device(slot->zdev);
+ }
+ return rc;
+}
+
+static int disable_slot(struct hotplug_slot *hotplug_slot)
+{
+ struct slot *slot = hotplug_slot->private;
+ int rc;
+
+ if (!zpci_fn_configured(slot->zdev->state))
+ return -EIO;
+
+ /* TODO: we rely on the user to unbind/remove the device, is that plausible
+ * or do we need to trigger that here?
+ */
+ rc = sclp_pci_deconfigure(slot->zdev->fid);
+ if (!rc) {
+ /* Fixme: better call List-PCI to find the disabled FH
+ for the FID since the FH should be opaque... */
+ slot->zdev->fh &= 0x7fffffff;
+ slot->zdev->state = ZPCI_FN_STATE_STANDBY;
+ }
+ return rc;
+}
+
+static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
+{
+ struct slot *slot = hotplug_slot->private;
+
+ switch (slot->zdev->state) {
+ case ZPCI_FN_STATE_STANDBY:
+ *value = 0;
+ break;
+ default:
+ *value = 1;
+ break;
+ }
+ return 0;
+}
+
+static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
+{
+ /* if the slot exits it always contains a function */
+ *value = 1;
+ return 0;
+}
+
+static void release_slot(struct hotplug_slot *hotplug_slot)
+{
+ struct slot *slot = hotplug_slot->private;
+
+ pr_debug("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
+ kfree(slot->hotplug_slot->info);
+ kfree(slot->hotplug_slot);
+ kfree(slot);
+}
+
+static struct hotplug_slot_ops s390_hotplug_slot_ops = {
+ .enable_slot = enable_slot,
+ .disable_slot = disable_slot,
+ .get_power_status = get_power_status,
+ .get_adapter_status = get_adapter_status,
+};
+
+static int init_pci_slot(struct zpci_dev *zdev)
+{
+ struct hotplug_slot *hotplug_slot;
+ struct hotplug_slot_info *info;
+ char name[SLOT_NAME_SIZE];
+ struct slot *slot;
+ int rc;
+
+ if (!zdev)
+ return 0;
+
+ slot = kzalloc(sizeof(*slot), GFP_KERNEL);
+ if (!slot)
+ goto error;
+
+ hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
+ if (!hotplug_slot)
+ goto error_hp;
+ hotplug_slot->private = slot;
+
+ slot->hotplug_slot = hotplug_slot;
+ slot->zdev = zdev;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ goto error_info;
+ hotplug_slot->info = info;
+
+ hotplug_slot->ops = &s390_hotplug_slot_ops;
+ hotplug_slot->release = &release_slot;
+
+ get_power_status(hotplug_slot, &info->power_status);
+ get_adapter_status(hotplug_slot, &info->adapter_status);
+
+ snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid);
+ rc = pci_hp_register(slot->hotplug_slot, zdev->bus,
+ ZPCI_DEVFN, name);
+ if (rc) {
+ pr_err("pci_hp_register failed with error %d\n", rc);
+ goto error_reg;
+ }
+ list_add(&slot->slot_list, &s390_hotplug_slot_list);
+ return 0;
+
+error_reg:
+ kfree(info);
+error_info:
+ kfree(hotplug_slot);
+error_hp:
+ kfree(slot);
+error:
+ return -ENOMEM;
+}
+
+static int __init init_pci_slots(void)
+{
+ struct zpci_dev *zdev;
+ int device = 0;
+
+ /*
+ * Create a structure for each slot, and register that slot
+ * with the pci_hotplug subsystem.
+ */
+ mutex_lock(&zpci_list_lock);
+ list_for_each_entry(zdev, &zpci_list, entry) {
+ init_pci_slot(zdev);
+ device++;
+ }
+
+ mutex_unlock(&zpci_list_lock);
+ return (device) ? 0 : -ENODEV;
+}
+
+static void exit_pci_slot(struct zpci_dev *zdev)
+{
+ struct list_head *tmp, *n;
+ struct slot *slot;
+
+ list_for_each_safe(tmp, n, &s390_hotplug_slot_list) {
+ slot = list_entry(tmp, struct slot, slot_list);
+ if (slot->zdev != zdev)
+ continue;
+ list_del(&slot->slot_list);
+ pci_hp_deregister(slot->hotplug_slot);
+ }
+}
+
+static void __exit exit_pci_slots(void)
+{
+ struct list_head *tmp, *n;
+ struct slot *slot;
+
+ /*
+ * Unregister all of our slots with the pci_hotplug subsystem.
+ * Memory will be freed in release_slot() callback after slot's
+ * lifespan is finished.
+ */
+ list_for_each_safe(tmp, n, &s390_hotplug_slot_list) {
+ slot = list_entry(tmp, struct slot, slot_list);
+ list_del(&slot->slot_list);
+ pci_hp_deregister(slot->hotplug_slot);
+ }
+}
+
+static int __init pci_hotplug_s390_init(void)
+{
+ /*
+ * Do specific initialization stuff for your driver here
+ * like initializing your controller hardware (if any) and
+ * determining the number of slots you have in the system
+ * right now.
+ */
+
+ if (!pci_probe)
+ return -EOPNOTSUPP;
+
+ /* register callbacks for slot handling from arch code */
+ mutex_lock(&zpci_list_lock);
+ hotplug_ops.create_slot = init_pci_slot;
+ hotplug_ops.remove_slot = exit_pci_slot;
+ mutex_unlock(&zpci_list_lock);
+ pr_info("registered hotplug slot callbacks\n");
+ return init_pci_slots();
+}
+
+static void __exit pci_hotplug_s390_exit(void)
+{
+ exit_pci_slots();
+}
+
+module_init(pci_hotplug_s390_init);
+module_exit(pci_hotplug_s390_exit);
diff --git a/drivers/s390/char/sclp.h b/drivers/s390/char/sclp.h
index d7e97ae..25bcd4c 100644
--- a/drivers/s390/char/sclp.h
+++ b/drivers/s390/char/sclp.h
@@ -1,5 +1,5 @@
/*
- * Copyright IBM Corp. 1999, 2009
+ * Copyright IBM Corp. 1999,2012
*
* Author(s): Martin Peschke <mpeschke@xxxxxxxxxx>
* Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
@@ -103,6 +103,7 @@ extern u64 sclp_facilities;
#define SCLP_HAS_CHP_RECONFIG (sclp_facilities & 0x2000000000000000ULL)
#define SCLP_HAS_CPU_INFO (sclp_facilities & 0x0800000000000000ULL)
#define SCLP_HAS_CPU_RECONFIG (sclp_facilities & 0x0400000000000000ULL)
+#define SCLP_HAS_PCI_RECONFIG (sclp_facilities & 0x0000000040000000ULL)
struct gds_subvector {
diff --git a/drivers/s390/char/sclp_cmd.c b/drivers/s390/char/sclp_cmd.c
index 71ea923c..f308bac 100644
--- a/drivers/s390/char/sclp_cmd.c
+++ b/drivers/s390/char/sclp_cmd.c
@@ -1,5 +1,5 @@
/*
- * Copyright IBM Corp. 2007, 2009
+ * Copyright IBM Corp. 2007,2012
*
* Author(s): Heiko Carstens <heiko.carstens@xxxxxxxxxx>,
* Peter Oberparleiter <peter.oberparleiter@xxxxxxxxxx>
@@ -12,6 +12,7 @@
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/err.h>
+#include <linux/export.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/mm.h>
@@ -702,6 +703,67 @@ __initcall(sclp_detect_standby_memory);
#endif /* CONFIG_MEMORY_HOTPLUG */
/*
+ * PCI I/O adapter configuration related functions.
+ */
+#define SCLP_CMDW_CONFIGURE_PCI 0x001a0001
+#define SCLP_CMDW_DECONFIGURE_PCI 0x001b0001
+
+#define SCLP_RECONFIG_PCI_ATPYE 2
+
+struct pci_cfg_sccb {
+ struct sccb_header header;
+ u8 atype; /* adapter type */
+ u8 reserved1;
+ u16 reserved2;
+ u32 aid; /* adapter identifier */
+} __packed;
+
+static int do_pci_configure(sclp_cmdw_t cmd, u32 fid)
+{
+ struct pci_cfg_sccb *sccb;
+ int rc;
+
+ if (!SCLP_HAS_PCI_RECONFIG)
+ return -EOPNOTSUPP;
+
+ sccb = (struct pci_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ if (!sccb)
+ return -ENOMEM;
+
+ sccb->header.length = PAGE_SIZE;
+ sccb->atype = SCLP_RECONFIG_PCI_ATPYE;
+ sccb->aid = fid;
+ rc = do_sync_request(cmd, sccb);
+ if (rc)
+ goto out;
+ switch (sccb->header.response_code) {
+ case 0x0020:
+ case 0x0120:
+ break;
+ default:
+ pr_warn("configure PCI I/O adapter failed: cmd=0x%08x response=0x%04x\n",
+ cmd, sccb->header.response_code);
+ rc = -EIO;
+ break;
+ }
+out:
+ free_page((unsigned long) sccb);
+ return rc;
+}
+
+int sclp_pci_configure(u32 fid)
+{
+ return do_pci_configure(SCLP_CMDW_CONFIGURE_PCI, fid);
+}
+EXPORT_SYMBOL(sclp_pci_configure);
+
+int sclp_pci_deconfigure(u32 fid)
+{
+ return do_pci_configure(SCLP_CMDW_DECONFIGURE_PCI, fid);
+}
+EXPORT_SYMBOL(sclp_pci_deconfigure);
+
+/*
* Channel path configuration related functions.
*/
--
1.7.12.4
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