linux/drivers/pci/hotplug/rpaphp_pci.c

197 lines
5.3 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0+
/*
* PCI Hot Plug Controller Driver for RPA-compliant PPC64 platform.
* Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
*
* All rights reserved.
*
* Send feedback to <lxie@us.ibm.com>
*
*/
#include <linux/of.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <asm/pci-bridge.h>
#include <asm/rtas.h>
#include <asm/machdep.h>
#include "../pci.h" /* for pci_add_new_bus */
#include "rpaphp.h"
PCI: rpaphp: Error out on busy status from get-sensor-state When certain PHB HW failure causes pHyp to recover PHB, it marks the PE state as temporarily unavailable until recovery is complete. This also triggers an EEH handler in Linux which needs to notify drivers, and perform recovery. But before notifying the driver about the PCI error it uses get_adapter_status()->rpaphp_get_sensor_state()->rtas_call(get-sensor-state) operation of the hotplug_slot to determine if the slot contains a device or not. If the slot is empty, the recovery is skipped entirely. eeh_event_handler() ->eeh_handle_normal_event() ->eeh_slot_presence_check() ->get_adapter_status() ->rpaphp_get_sensor_state() ->rtas_get_sensor() ->rtas_call(get-sensor-state) However on certain PHB failures, the RTAS call rtas_call(get-sensor-state) returns extended busy error (9902) until PHB is recovered by pHyp. Once PHB is recovered, the rtas_call(get-sensor-state) returns success with correct presence status. The RTAS call interface rtas_get_sensor() loops over the RTAS call on extended delay return code (9902) until the return value is either success (0) or error (-1). This causes the EEH handler to get stuck for ~6 seconds before it could notify that the PCI error has been detected and stop any active operations. Hence with running I/O traffic, during this 6 seconds, the network driver continues its operation and hits a timeout (netdev watchdog). ------------ [52732.244731] DEBUG: ibm_read_slot_reset_state2() [52732.244762] DEBUG: ret = 0, rets[0]=5, rets[1]=1, rets[2]=4000, rets[3]=> [52732.244798] DEBUG: in eeh_slot_presence_check [52732.244804] DEBUG: error state check [52732.244807] DEBUG: Is slot hotpluggable [52732.244810] DEBUG: hotpluggable ops ? [52732.244953] DEBUG: Calling ops->get_adapter_status [52732.244958] DEBUG: calling rpaphp_get_sensor_state [52736.564262] ------------[ cut here ]------------ [52736.564299] NETDEV WATCHDOG: enP64p1s0f3 (tg3): transmit queue 0 timed o> [52736.564324] WARNING: CPU: 1442 PID: 0 at net/sched/sch_generic.c:478 dev> [...] [52736.564505] NIP [c000000000c32368] dev_watchdog+0x438/0x440 [52736.564513] LR [c000000000c32364] dev_watchdog+0x434/0x440 ------------ On timeouts, network driver starts dumping debug information to console (e.g bnx2 driver calls bnx2x_panic_dump()), and go into recovery path while pHyp is still recovering the PHB. As part of recovery, the driver tries to reset the device and it keeps failing since every PCI read/write returns ff's. And when EEH recovery kicks-in, the driver is unable to recover the device. This impacts the ssh connection and leads to the system being inaccessible. To get the NIC working again it needs a reboot or re-assign the I/O adapter from HMC. [ 9531.168587] EEH: Beginning: 'slot_reset' [ 9531.168601] PCI 0013:01:00.0#10000: EEH: Invoking bnx2x->slot_reset() [...] [ 9614.110094] bnx2x: [bnx2x_func_stop:9129(enP19p1s0f0)]FUNC_STOP ramrod failed. Running a dry transaction [ 9614.110300] bnx2x: [bnx2x_igu_int_disable:902(enP19p1s0f0)]BUG! Proper val not read from IGU! [ 9629.178067] bnx2x: [bnx2x_fw_command:3055(enP19p1s0f0)]FW failed to respond! [ 9629.178085] bnx2x 0013:01:00.0 enP19p1s0f0: bc 7.10.4 [ 9629.178091] bnx2x: [bnx2x_fw_dump_lvl:789(enP19p1s0f0)]Cannot dump MCP info while in PCI error [ 9644.241813] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f0)]IO slot reset --> driver unload [...] [ 9644.241819] PCI 0013:01:00.0#10000: EEH: bnx2x driver reports: 'disconnect' [ 9644.241823] PCI 0013:01:00.1#10000: EEH: Invoking bnx2x->slot_reset() [ 9644.241827] bnx2x: [bnx2x_io_slot_reset:14229(enP19p1s0f1)]IO slot reset initializing... [ 9644.241916] bnx2x 0013:01:00.1: enabling device (0140 -> 0142) [ 9644.258604] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f1)]IO slot reset --> driver unload [ 9644.258612] PCI 0013:01:00.1#10000: EEH: bnx2x driver reports: 'disconnect' [ 9644.258615] EEH: Finished:'slot_reset' with aggregate recovery state:'disconnect' [ 9644.258620] EEH: Unable to recover from failure from PHB#13-PE#10000. [ 9644.261811] EEH: Beginning: 'error_detected(permanent failure)' [...] [ 9644.261823] EEH: Finished:'error_detected(permanent failure)' Hence, it becomes important to inform driver about the PCI error detection as early as possible, so that driver is aware of PCI error and waits for EEH handler's next action for successful recovery. Current implementation uses rtas_get_sensor() API which blocks the slot check state until RTAS call returns success. To avoid this, fix the PCI hotplug driver (rpaphp) to return an error (-EBUSY) if the slot presence state can not be detected immediately while PE is in EEH recovery state. Change rpaphp_get_sensor_state() to invoke rtas_call(get-sensor-state) directly only if the respective PE is in EEH recovery state, and take actions based on RTAS return status. This way EEH handler will not be blocked on rpaphp_get_sensor_state() and can immediately notify driver about the PCI error and stop any active operations. In normal cases (non-EEH case) rpaphp_get_sensor_state() will continue to invoke rtas_get_sensor() as it was earlier with no change in existing behavior. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/169235815601.193557.13989873835811325343.stgit@jupiter
2023-08-18 16:59:43 +05:30
/*
* RTAS call get-sensor-state(DR_ENTITY_SENSE) return values as per PAPR:
* -- generic return codes ---
* -1: Hardware Error
* -2: RTAS_BUSY
* -3: Invalid sensor. RTAS Parameter Error.
* -- rtas_get_sensor function specific return codes ---
* -9000: Need DR entity to be powered up and unisolated before RTAS call
* -9001: Need DR entity to be powered up, but not unisolated, before RTAS call
* -9002: DR entity unusable
* 990x: Extended delay - where x is a number in the range of 0-5
*/
#define RTAS_SLOT_UNISOLATED -9000
#define RTAS_SLOT_NOT_UNISOLATED -9001
#define RTAS_SLOT_NOT_USABLE -9002
static int rtas_get_sensor_errno(int rtas_rc)
{
switch (rtas_rc) {
case 0:
/* Success case */
return 0;
case RTAS_SLOT_UNISOLATED:
case RTAS_SLOT_NOT_UNISOLATED:
return -EFAULT;
case RTAS_SLOT_NOT_USABLE:
return -ENODEV;
case RTAS_BUSY:
case RTAS_EXTENDED_DELAY_MIN...RTAS_EXTENDED_DELAY_MAX:
return -EBUSY;
default:
return rtas_error_rc(rtas_rc);
}
}
/*
* get_adapter_status() can be called by the EEH handler during EEH recovery.
* On certain PHB failures, the RTAS call rtas_call(get-sensor-state) returns
* extended busy error (9902) until PHB is recovered by pHyp. The RTAS call
* interface rtas_get_sensor() loops over the RTAS call on extended delay
* return code (9902) until the return value is either success (0) or error
* (-1). This causes the EEH handler to get stuck for ~6 seconds before it
* could notify that the PCI error has been detected and stop any active
* operations. This sometimes causes EEH recovery to fail. To avoid this issue,
* invoke rtas_call(get-sensor-state) directly if the respective PE is in EEH
* recovery state and return -EBUSY error based on RTAS return status. This
* will help the EEH handler to notify the driver about the PCI error
* immediately and successfully proceed with EEH recovery steps.
*/
static int __rpaphp_get_sensor_state(struct slot *slot, int *state)
{
int rc;
int token = rtas_token("get-sensor-state");
struct pci_dn *pdn;
struct eeh_pe *pe;
struct pci_controller *phb = PCI_DN(slot->dn)->phb;
if (token == RTAS_UNKNOWN_SERVICE)
return -ENOENT;
/*
* Fallback to existing method for empty slot or PE isn't in EEH
* recovery.
*/
pdn = list_first_entry_or_null(&PCI_DN(phb->dn)->child_list,
struct pci_dn, list);
if (!pdn)
goto fallback;
pe = eeh_dev_to_pe(pdn->edev);
if (pe && (pe->state & EEH_PE_RECOVERING)) {
rc = rtas_call(token, 2, 2, state, DR_ENTITY_SENSE,
slot->index);
return rtas_get_sensor_errno(rc);
}
fallback:
return rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
}
int rpaphp_get_sensor_state(struct slot *slot, int *state)
{
int rc;
int setlevel;
PCI: rpaphp: Error out on busy status from get-sensor-state When certain PHB HW failure causes pHyp to recover PHB, it marks the PE state as temporarily unavailable until recovery is complete. This also triggers an EEH handler in Linux which needs to notify drivers, and perform recovery. But before notifying the driver about the PCI error it uses get_adapter_status()->rpaphp_get_sensor_state()->rtas_call(get-sensor-state) operation of the hotplug_slot to determine if the slot contains a device or not. If the slot is empty, the recovery is skipped entirely. eeh_event_handler() ->eeh_handle_normal_event() ->eeh_slot_presence_check() ->get_adapter_status() ->rpaphp_get_sensor_state() ->rtas_get_sensor() ->rtas_call(get-sensor-state) However on certain PHB failures, the RTAS call rtas_call(get-sensor-state) returns extended busy error (9902) until PHB is recovered by pHyp. Once PHB is recovered, the rtas_call(get-sensor-state) returns success with correct presence status. The RTAS call interface rtas_get_sensor() loops over the RTAS call on extended delay return code (9902) until the return value is either success (0) or error (-1). This causes the EEH handler to get stuck for ~6 seconds before it could notify that the PCI error has been detected and stop any active operations. Hence with running I/O traffic, during this 6 seconds, the network driver continues its operation and hits a timeout (netdev watchdog). ------------ [52732.244731] DEBUG: ibm_read_slot_reset_state2() [52732.244762] DEBUG: ret = 0, rets[0]=5, rets[1]=1, rets[2]=4000, rets[3]=> [52732.244798] DEBUG: in eeh_slot_presence_check [52732.244804] DEBUG: error state check [52732.244807] DEBUG: Is slot hotpluggable [52732.244810] DEBUG: hotpluggable ops ? [52732.244953] DEBUG: Calling ops->get_adapter_status [52732.244958] DEBUG: calling rpaphp_get_sensor_state [52736.564262] ------------[ cut here ]------------ [52736.564299] NETDEV WATCHDOG: enP64p1s0f3 (tg3): transmit queue 0 timed o> [52736.564324] WARNING: CPU: 1442 PID: 0 at net/sched/sch_generic.c:478 dev> [...] [52736.564505] NIP [c000000000c32368] dev_watchdog+0x438/0x440 [52736.564513] LR [c000000000c32364] dev_watchdog+0x434/0x440 ------------ On timeouts, network driver starts dumping debug information to console (e.g bnx2 driver calls bnx2x_panic_dump()), and go into recovery path while pHyp is still recovering the PHB. As part of recovery, the driver tries to reset the device and it keeps failing since every PCI read/write returns ff's. And when EEH recovery kicks-in, the driver is unable to recover the device. This impacts the ssh connection and leads to the system being inaccessible. To get the NIC working again it needs a reboot or re-assign the I/O adapter from HMC. [ 9531.168587] EEH: Beginning: 'slot_reset' [ 9531.168601] PCI 0013:01:00.0#10000: EEH: Invoking bnx2x->slot_reset() [...] [ 9614.110094] bnx2x: [bnx2x_func_stop:9129(enP19p1s0f0)]FUNC_STOP ramrod failed. Running a dry transaction [ 9614.110300] bnx2x: [bnx2x_igu_int_disable:902(enP19p1s0f0)]BUG! Proper val not read from IGU! [ 9629.178067] bnx2x: [bnx2x_fw_command:3055(enP19p1s0f0)]FW failed to respond! [ 9629.178085] bnx2x 0013:01:00.0 enP19p1s0f0: bc 7.10.4 [ 9629.178091] bnx2x: [bnx2x_fw_dump_lvl:789(enP19p1s0f0)]Cannot dump MCP info while in PCI error [ 9644.241813] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f0)]IO slot reset --> driver unload [...] [ 9644.241819] PCI 0013:01:00.0#10000: EEH: bnx2x driver reports: 'disconnect' [ 9644.241823] PCI 0013:01:00.1#10000: EEH: Invoking bnx2x->slot_reset() [ 9644.241827] bnx2x: [bnx2x_io_slot_reset:14229(enP19p1s0f1)]IO slot reset initializing... [ 9644.241916] bnx2x 0013:01:00.1: enabling device (0140 -> 0142) [ 9644.258604] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f1)]IO slot reset --> driver unload [ 9644.258612] PCI 0013:01:00.1#10000: EEH: bnx2x driver reports: 'disconnect' [ 9644.258615] EEH: Finished:'slot_reset' with aggregate recovery state:'disconnect' [ 9644.258620] EEH: Unable to recover from failure from PHB#13-PE#10000. [ 9644.261811] EEH: Beginning: 'error_detected(permanent failure)' [...] [ 9644.261823] EEH: Finished:'error_detected(permanent failure)' Hence, it becomes important to inform driver about the PCI error detection as early as possible, so that driver is aware of PCI error and waits for EEH handler's next action for successful recovery. Current implementation uses rtas_get_sensor() API which blocks the slot check state until RTAS call returns success. To avoid this, fix the PCI hotplug driver (rpaphp) to return an error (-EBUSY) if the slot presence state can not be detected immediately while PE is in EEH recovery state. Change rpaphp_get_sensor_state() to invoke rtas_call(get-sensor-state) directly only if the respective PE is in EEH recovery state, and take actions based on RTAS return status. This way EEH handler will not be blocked on rpaphp_get_sensor_state() and can immediately notify driver about the PCI error and stop any active operations. In normal cases (non-EEH case) rpaphp_get_sensor_state() will continue to invoke rtas_get_sensor() as it was earlier with no change in existing behavior. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/169235815601.193557.13989873835811325343.stgit@jupiter
2023-08-18 16:59:43 +05:30
rc = __rpaphp_get_sensor_state(slot, state);
if (rc < 0) {
if (rc == -EFAULT || rc == -EEXIST) {
dbg("%s: slot must be power up to get sensor-state\n",
__func__);
/* some slots have to be powered up
* before get-sensor will succeed.
*/
rc = rtas_set_power_level(slot->power_domain, POWER_ON,
&setlevel);
if (rc < 0) {
dbg("%s: power on slot[%s] failed rc=%d.\n",
__func__, slot->name, rc);
} else {
PCI: rpaphp: Error out on busy status from get-sensor-state When certain PHB HW failure causes pHyp to recover PHB, it marks the PE state as temporarily unavailable until recovery is complete. This also triggers an EEH handler in Linux which needs to notify drivers, and perform recovery. But before notifying the driver about the PCI error it uses get_adapter_status()->rpaphp_get_sensor_state()->rtas_call(get-sensor-state) operation of the hotplug_slot to determine if the slot contains a device or not. If the slot is empty, the recovery is skipped entirely. eeh_event_handler() ->eeh_handle_normal_event() ->eeh_slot_presence_check() ->get_adapter_status() ->rpaphp_get_sensor_state() ->rtas_get_sensor() ->rtas_call(get-sensor-state) However on certain PHB failures, the RTAS call rtas_call(get-sensor-state) returns extended busy error (9902) until PHB is recovered by pHyp. Once PHB is recovered, the rtas_call(get-sensor-state) returns success with correct presence status. The RTAS call interface rtas_get_sensor() loops over the RTAS call on extended delay return code (9902) until the return value is either success (0) or error (-1). This causes the EEH handler to get stuck for ~6 seconds before it could notify that the PCI error has been detected and stop any active operations. Hence with running I/O traffic, during this 6 seconds, the network driver continues its operation and hits a timeout (netdev watchdog). ------------ [52732.244731] DEBUG: ibm_read_slot_reset_state2() [52732.244762] DEBUG: ret = 0, rets[0]=5, rets[1]=1, rets[2]=4000, rets[3]=> [52732.244798] DEBUG: in eeh_slot_presence_check [52732.244804] DEBUG: error state check [52732.244807] DEBUG: Is slot hotpluggable [52732.244810] DEBUG: hotpluggable ops ? [52732.244953] DEBUG: Calling ops->get_adapter_status [52732.244958] DEBUG: calling rpaphp_get_sensor_state [52736.564262] ------------[ cut here ]------------ [52736.564299] NETDEV WATCHDOG: enP64p1s0f3 (tg3): transmit queue 0 timed o> [52736.564324] WARNING: CPU: 1442 PID: 0 at net/sched/sch_generic.c:478 dev> [...] [52736.564505] NIP [c000000000c32368] dev_watchdog+0x438/0x440 [52736.564513] LR [c000000000c32364] dev_watchdog+0x434/0x440 ------------ On timeouts, network driver starts dumping debug information to console (e.g bnx2 driver calls bnx2x_panic_dump()), and go into recovery path while pHyp is still recovering the PHB. As part of recovery, the driver tries to reset the device and it keeps failing since every PCI read/write returns ff's. And when EEH recovery kicks-in, the driver is unable to recover the device. This impacts the ssh connection and leads to the system being inaccessible. To get the NIC working again it needs a reboot or re-assign the I/O adapter from HMC. [ 9531.168587] EEH: Beginning: 'slot_reset' [ 9531.168601] PCI 0013:01:00.0#10000: EEH: Invoking bnx2x->slot_reset() [...] [ 9614.110094] bnx2x: [bnx2x_func_stop:9129(enP19p1s0f0)]FUNC_STOP ramrod failed. Running a dry transaction [ 9614.110300] bnx2x: [bnx2x_igu_int_disable:902(enP19p1s0f0)]BUG! Proper val not read from IGU! [ 9629.178067] bnx2x: [bnx2x_fw_command:3055(enP19p1s0f0)]FW failed to respond! [ 9629.178085] bnx2x 0013:01:00.0 enP19p1s0f0: bc 7.10.4 [ 9629.178091] bnx2x: [bnx2x_fw_dump_lvl:789(enP19p1s0f0)]Cannot dump MCP info while in PCI error [ 9644.241813] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f0)]IO slot reset --> driver unload [...] [ 9644.241819] PCI 0013:01:00.0#10000: EEH: bnx2x driver reports: 'disconnect' [ 9644.241823] PCI 0013:01:00.1#10000: EEH: Invoking bnx2x->slot_reset() [ 9644.241827] bnx2x: [bnx2x_io_slot_reset:14229(enP19p1s0f1)]IO slot reset initializing... [ 9644.241916] bnx2x 0013:01:00.1: enabling device (0140 -> 0142) [ 9644.258604] bnx2x: [bnx2x_io_slot_reset:14245(enP19p1s0f1)]IO slot reset --> driver unload [ 9644.258612] PCI 0013:01:00.1#10000: EEH: bnx2x driver reports: 'disconnect' [ 9644.258615] EEH: Finished:'slot_reset' with aggregate recovery state:'disconnect' [ 9644.258620] EEH: Unable to recover from failure from PHB#13-PE#10000. [ 9644.261811] EEH: Beginning: 'error_detected(permanent failure)' [...] [ 9644.261823] EEH: Finished:'error_detected(permanent failure)' Hence, it becomes important to inform driver about the PCI error detection as early as possible, so that driver is aware of PCI error and waits for EEH handler's next action for successful recovery. Current implementation uses rtas_get_sensor() API which blocks the slot check state until RTAS call returns success. To avoid this, fix the PCI hotplug driver (rpaphp) to return an error (-EBUSY) if the slot presence state can not be detected immediately while PE is in EEH recovery state. Change rpaphp_get_sensor_state() to invoke rtas_call(get-sensor-state) directly only if the respective PE is in EEH recovery state, and take actions based on RTAS return status. This way EEH handler will not be blocked on rpaphp_get_sensor_state() and can immediately notify driver about the PCI error and stop any active operations. In normal cases (non-EEH case) rpaphp_get_sensor_state() will continue to invoke rtas_get_sensor() as it was earlier with no change in existing behavior. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/169235815601.193557.13989873835811325343.stgit@jupiter
2023-08-18 16:59:43 +05:30
rc = __rpaphp_get_sensor_state(slot, state);
}
} else if (rc == -ENODEV)
info("%s: slot is unusable\n", __func__);
else
err("%s failed to get sensor state\n", __func__);
}
return rc;
}
/**
* rpaphp_enable_slot - record slot state, config pci device
* @slot: target &slot
*
PCI: hotplug: Drop hotplug_slot_info Ever since the PCI hotplug core was introduced in 2002, drivers had to allocate and register a struct hotplug_slot_info for every slot: https://git.kernel.org/tglx/history/c/a8a2069f432c Apparently the idea was that drivers furnish the hotplug core with an up-to-date card presence status, power status, latch status and attention indicator status as well as notify the hotplug core of changes thereof. However only 4 out of 12 hotplug drivers bother to notify the hotplug core with pci_hp_change_slot_info() and the hotplug core never made any use of the information: There is just a single macro in pci_hotplug_core.c, GET_STATUS(), which uses the hotplug_slot_info if the driver lacks the corresponding callback in hotplug_slot_ops. The macro is called when the user reads the attribute via sysfs. Now, if the callback isn't defined, the attribute isn't exposed in sysfs in the first place (see e.g. has_power_file()). There are only two situations when the hotplug_slot_info would actually be accessed: * If the driver defines ->enable_slot or ->disable_slot but not ->get_power_status. * If the driver defines ->set_attention_status but not ->get_attention_status. There is no driver doing the former and just a single driver doing the latter, namely pnv_php.c. Amend it with a ->get_attention_status callback. With that, the hotplug_slot_info becomes completely unused by the PCI hotplug core. But a few drivers use it internally as a cache: cpcihp uses it to cache the latch_status and adapter_status. cpqhp uses it to cache the adapter_status. pnv_php and rpaphp use it to cache the attention_status. shpchp uses it to cache all four values. Amend these drivers to cache the information in their private slot struct. shpchp's slot struct already contains members to cache the power_status and adapter_status, so additional members are only needed for the other two values. In the case of cpqphp, the cached value is only accessed in a single place, so instead of caching it, read the current value from the hardware. Caution: acpiphp, cpci, cpqhp, shpchp, asus-wmi and eeepc-laptop populate the hotplug_slot_info with initial values on probe. That code is herewith removed. There is a theoretical chance that the code has side effects without which the driver fails to function, e.g. if the ACPI method to read the adapter status needs to be executed at least once on probe. That seems unlikely to me, still maintainers should review the changes carefully for this possibility. Rafael adds: "I'm not aware of any case in which it will break anything, [...] but if that happens, it may be necessary to add the execution of the control methods in question directly to the initialization part." Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> # drivers/pci/hotplug/rpa* Acked-by: Sebastian Ott <sebott@linux.ibm.com> # drivers/pci/hotplug/s390* Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86 Cc: Len Brown <lenb@kernel.org> Cc: Scott Murray <scott@spiteful.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Oliver OHalloran <oliveroh@au1.ibm.com> Cc: Gavin Shan <gwshan@linux.vnet.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Corentin Chary <corentin.chary@gmail.com> Cc: Darren Hart <dvhart@infradead.org>
2018-09-08 09:59:01 +02:00
* Initialize values in the slot structure to indicate if there is a pci card
* plugged into the slot. If the slot is not empty, run the pcibios routine
* to get pcibios stuff correctly set up.
*/
int rpaphp_enable_slot(struct slot *slot)
{
int rc, level, state;
struct pci_bus *bus;
slot->state = EMPTY;
/* Find out if the power is turned on for the slot */
rc = rtas_get_power_level(slot->power_domain, &level);
if (rc)
return rc;
/* Figure out if there is an adapter in the slot */
rc = rpaphp_get_sensor_state(slot, &state);
if (rc)
return rc;
bus = pci_find_bus_by_node(slot->dn);
if (!bus) {
err("%s: no pci_bus for dn %pOF\n", __func__, slot->dn);
return -EINVAL;
}
slot->bus = bus;
slot->pci_devs = &bus->devices;
/* if there's an adapter in the slot, go add the pci devices */
if (state == PRESENT) {
slot->state = NOT_CONFIGURED;
/* non-empty slot has to have child */
if (!slot->dn->child) {
err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
__func__, slot->name);
return -EINVAL;
}
powerpc/eeh: Do early EEH init only when required The pci hotplug helper (pci_hp_add_devices()) calls eeh_add_device_tree_early() to scan the device-tree for new PCI devices and do the early EEH probe before the device is scanned. This early probe is a no-op in a lot of cases because: a) The early init is only required to satisfy a PAPR requirement that EEH be configured before we start doing config accesses. On PowerNV it is a no-op. b) It's a no-op for devices that have already had their eeh_dev initialised. There are four callers of pci_hp_add_devices(): 1. arch/powerpc/kernel/eeh_driver.c Here the hotplug helper is called when re-scanning pci_devs that were removed during an EEH recovery pass. The EEH stat for each removed device (the eeh_dev) is retained across a recovery pass so the early init is a no-op in this case. 2. drivers/pci/hotplug/pnv_php.c This is also a no-op since the PowerNV hotplug driver is, suprisingly, PowerNV specific. 3. drivers/pci/hotplug/rpaphp_core.c 4. drivers/pci/hotplug/rpaphp_pci.c In these two cases new devices have been hotplugged and FW has provided new DT nodes for each. These are the only two cases where the EEH we might have new PCI device nodes in the DT so these are the only two cases where the early EEH probe needs to be done. We can move the calls to eeh_add_device_tree_early() to the locations where it's needed and remove it from the generic path. This is preparation for making the early EEH probe pseries specific. Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-3-oohall@gmail.com
2020-03-06 18:39:01 +11:00
if (list_empty(&bus->devices)) {
pseries_eeh_init_edev_recursive(PCI_DN(slot->dn));
pci_hp_add_devices(bus);
powerpc/eeh: Do early EEH init only when required The pci hotplug helper (pci_hp_add_devices()) calls eeh_add_device_tree_early() to scan the device-tree for new PCI devices and do the early EEH probe before the device is scanned. This early probe is a no-op in a lot of cases because: a) The early init is only required to satisfy a PAPR requirement that EEH be configured before we start doing config accesses. On PowerNV it is a no-op. b) It's a no-op for devices that have already had their eeh_dev initialised. There are four callers of pci_hp_add_devices(): 1. arch/powerpc/kernel/eeh_driver.c Here the hotplug helper is called when re-scanning pci_devs that were removed during an EEH recovery pass. The EEH stat for each removed device (the eeh_dev) is retained across a recovery pass so the early init is a no-op in this case. 2. drivers/pci/hotplug/pnv_php.c This is also a no-op since the PowerNV hotplug driver is, suprisingly, PowerNV specific. 3. drivers/pci/hotplug/rpaphp_core.c 4. drivers/pci/hotplug/rpaphp_pci.c In these two cases new devices have been hotplugged and FW has provided new DT nodes for each. These are the only two cases where the EEH we might have new PCI device nodes in the DT so these are the only two cases where the early EEH probe needs to be done. We can move the calls to eeh_add_device_tree_early() to the locations where it's needed and remove it from the generic path. This is preparation for making the early EEH probe pseries specific. Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200306073904.4737-3-oohall@gmail.com
2020-03-06 18:39:01 +11:00
}
if (!list_empty(&bus->devices)) {
slot->state = CONFIGURED;
}
if (rpaphp_debug) {
struct pci_dev *dev;
dbg("%s: pci_devs of slot[%pOF]\n", __func__, slot->dn);
list_for_each_entry(dev, &bus->devices, bus_list)
dbg("\t%s\n", pci_name(dev));
}
}
return 0;
}