Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 196 insertions, 0 deletions

diff --git a/drivers/pci/hotplug/rpaphp_pci.c b/drivers/pci/hotplug/rpaphp_pci.c
new file mode 100644
index 0000000000..bcfd26ec6d
--- /dev/null
+++ b/drivers/pci/hotplug/rpaphp_pci.c
@@ -0,0 +1,196 @@
+// 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"
+
+/*
+ * 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;
+
+	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 {
+				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
+ *
+ * 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;
+		}
+
+		if (list_empty(&bus->devices)) {
+			pseries_eeh_init_edev_recursive(PCI_DN(slot->dn));
+			pci_hp_add_devices(bus);
+		}
+
+		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;
+}