alistair23-linux/arch/s390/pci/pci_event.c
Sebastian Ott ca25f564c4 s390/pci: improve state check when processing hotplug events
Processing pci hotplug events can fail when a pci function is in an
unexpected state. This can happen when we already processed the
change associated with the hotplug event (especially when receiving
hotplug events during early boot).
Just ignore the event in this case.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-05-20 08:58:48 +02:00

137 lines
3.1 KiB
C

/*
* Copyright IBM Corp. 2012
*
* Author(s):
* Jan Glauber <jang@linux.vnet.ibm.com>
*/
#define COMPONENT "zPCI"
#define pr_fmt(fmt) COMPONENT ": " fmt
#include <linux/kernel.h>
#include <linux/pci.h>
#include <asm/pci_debug.h>
#include <asm/sclp.h>
/* Content Code Description for PCI Function Error */
struct zpci_ccdf_err {
u32 reserved1;
u32 fh; /* function handle */
u32 fid; /* function id */
u32 ett : 4; /* expected table type */
u32 mvn : 12; /* MSI vector number */
u32 dmaas : 8; /* DMA address space */
u32 : 6;
u32 q : 1; /* event qualifier */
u32 rw : 1; /* read/write */
u64 faddr; /* failing address */
u32 reserved3;
u16 reserved4;
u16 pec; /* PCI event code */
} __packed;
/* Content Code Description for PCI Function Availability */
struct zpci_ccdf_avail {
u32 reserved1;
u32 fh; /* function handle */
u32 fid; /* function id */
u32 reserved2;
u32 reserved3;
u32 reserved4;
u32 reserved5;
u16 reserved6;
u16 pec; /* PCI event code */
} __packed;
static void __zpci_event_error(struct zpci_ccdf_err *ccdf)
{
struct zpci_dev *zdev = get_zdev_by_fid(ccdf->fid);
zpci_err("error CCDF:\n");
zpci_err_hex(ccdf, sizeof(*ccdf));
if (!zdev)
return;
pr_err("%s: Event 0x%x reports an error for PCI function 0x%x\n",
pci_name(zdev->pdev), ccdf->pec, ccdf->fid);
}
void zpci_event_error(void *data)
{
if (zpci_is_enabled())
__zpci_event_error(data);
}
static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
{
struct zpci_dev *zdev = get_zdev_by_fid(ccdf->fid);
struct pci_dev *pdev = zdev ? zdev->pdev : NULL;
int ret;
pr_info("%s: Event 0x%x reconfigured PCI function 0x%x\n",
pdev ? pci_name(pdev) : "n/a", ccdf->pec, ccdf->fid);
zpci_err("avail CCDF:\n");
zpci_err_hex(ccdf, sizeof(*ccdf));
switch (ccdf->pec) {
case 0x0301: /* Standby -> Configured */
if (!zdev || zdev->state != ZPCI_FN_STATE_STANDBY)
break;
zdev->state = ZPCI_FN_STATE_CONFIGURED;
zdev->fh = ccdf->fh;
ret = zpci_enable_device(zdev);
if (ret)
break;
pci_rescan_bus(zdev->bus);
break;
case 0x0302: /* Reserved -> Standby */
if (!zdev)
clp_add_pci_device(ccdf->fid, ccdf->fh, 0);
break;
case 0x0303: /* Deconfiguration requested */
if (pdev)
pci_stop_and_remove_bus_device(pdev);
ret = zpci_disable_device(zdev);
if (ret)
break;
ret = sclp_pci_deconfigure(zdev->fid);
zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
if (!ret)
zdev->state = ZPCI_FN_STATE_STANDBY;
break;
case 0x0304: /* Configured -> Standby */
if (pdev) {
/* Give the driver a hint that the function is
* already unusable. */
pdev->error_state = pci_channel_io_perm_failure;
pci_stop_and_remove_bus_device(pdev);
}
zdev->fh = ccdf->fh;
zpci_disable_device(zdev);
zdev->state = ZPCI_FN_STATE_STANDBY;
break;
case 0x0306: /* 0x308 or 0x302 for multiple devices */
clp_rescan_pci_devices();
break;
case 0x0308: /* Standby -> Reserved */
if (!zdev)
break;
pci_stop_root_bus(zdev->bus);
pci_remove_root_bus(zdev->bus);
break;
default:
break;
}
}
void zpci_event_availability(void *data)
{
if (zpci_is_enabled())
__zpci_event_availability(data);
}