core/pci-slot.c - skiboot - Git at Google

 // SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 /*
  * PCI Slots
  *
  * Copyright 2013-2019 IBM Corp.
  */

 #include <skiboot.h>
 #include <opal-msg.h>
 #include <pci-cfg.h>
 #include <pci.h>
 #include <pci-slot.h>

 /* Debugging options */
 #define PCI_SLOT_PREFIX	"PCI-SLOT-%016llx "
 #define PCI_SLOT_DBG(s, fmt, a...)		 \
 	prlog(PR_DEBUG, PCI_SLOT_PREFIX fmt, (s)->id, ##a)

 static void pci_slot_prepare_link_change(struct pci_slot *slot, bool up)
 {
 	struct phb *phb = slot->phb;
 	struct pci_device *pd = slot->pd;
 	uint32_t aercap, mask;

 	/*
 	 * Mask the link down and receiver error before the link becomes
 	 * down. Otherwise, unmask the errors when the link is up.
 	 */
 	if (pci_has_cap(pd, PCIECAP_ID_AER, true)) {
 		aercap = pci_cap(pd, PCIECAP_ID_AER, true);

 		/* Mask link surprise down event. The event is always
 		 * masked when the associated PCI slot supports PCI
 		 * surprise hotplug. We needn't toggle it when the link
 		 * bounces caused by reset and just keep it always masked.
 		 */
 		if (!pd->slot || !pd->slot->surprise_pluggable) {
 			pci_cfg_read32(phb, pd->bdfn,
 				       aercap + PCIECAP_AER_UE_MASK, &mask);
 			if (up)
 				mask &= ~PCIECAP_AER_UE_MASK_SURPRISE_DOWN;
 			else
 				mask |= PCIECAP_AER_UE_MASK_SURPRISE_DOWN;
 			pci_cfg_write32(phb, pd->bdfn,
 					aercap + PCIECAP_AER_UE_MASK, mask);
 		}

 		/* Receiver error */
 		pci_cfg_read32(phb, pd->bdfn, aercap + PCIECAP_AER_CE_MASK,
 			       &mask);
 		if (up)
 			mask &= ~PCIECAP_AER_CE_RECVR_ERR;
 		else
 			mask |= PCIECAP_AER_CE_RECVR_ERR;
 		pci_cfg_write32(phb, pd->bdfn, aercap + PCIECAP_AER_CE_MASK,
 				mask);
 	}

 	/*
 	 * We're coming back from reset. We need restore bus ranges
 	 * and reinitialize the affected bridges and devices.
 	 */
 	if (up) {
 		pci_restore_bridge_buses(phb, pd);
 		if (phb->ops->device_init)
 			pci_walk_dev(phb, pd, phb->ops->device_init, NULL);
 	}
 }

 static int64_t pci_slot_run_sm(struct pci_slot *slot)
 {
 	uint64_t now = mftb();
 	int64_t ret;

 	/* Return remaining timeout if we're still waiting */
 	if (slot->delay_tgt_tb &&
 	    tb_compare(now, slot->delay_tgt_tb) == TB_ABEFOREB)
 		return slot->delay_tgt_tb - now;

 	slot->delay_tgt_tb = 0;
 	switch (slot->state & PCI_SLOT_STATE_MASK) {
 	case PCI_SLOT_STATE_LINK:
 		ret = slot->ops.poll_link(slot);
 		break;
 	case PCI_SLOT_STATE_HRESET:
 		ret = slot->ops.hreset(slot);
 		break;
 	case PCI_SLOT_STATE_FRESET:
 		ret = slot->ops.freset(slot);
 		break;
 	case PCI_SLOT_STATE_CRESET:
 		ret = slot->ops.creset(slot);
 		break;
 	default:
 		prlog(PR_ERR, PCI_SLOT_PREFIX
 		      "Invalid state %08x\n", slot->id, slot->state);
 		pci_slot_set_state(slot, PCI_SLOT_STATE_NORMAL);
 		ret = OPAL_HARDWARE;
 	}

 	/* Notify about the pci slot state machine completion */
 	if (ret <= 0 && slot->ops.completed_sm_run)
 		slot->ops.completed_sm_run(slot, ret);

 	return ret;
 }

 void pci_slot_add_dt_properties(struct pci_slot *slot,
 				struct dt_node *np)
 {
 	/* Bail without device node */
 	if (!np)
 		return;

 	dt_add_property_cells(np, "ibm,reset-by-firmware", 1);
 	dt_add_property_cells(np, "ibm,slot-pluggable", slot->pluggable);
 	dt_add_property_cells(np, "ibm,slot-surprise-pluggable",
 			      slot->surprise_pluggable);
 	if (pci_slot_has_flags(slot, PCI_SLOT_FLAG_BROKEN_PDC))
 		dt_add_property_cells(np, "ibm,slot-broken-pdc", 1);

 	dt_add_property_cells(np, "ibm,slot-power-ctl", slot->power_ctl);
 	dt_add_property_cells(np, "ibm,slot-power-led-ctlled",
 			      slot->power_led_ctl);
 	dt_add_property_cells(np, "ibm,slot-attn-led", slot->attn_led_ctl);
 	dt_add_property_cells(np, "ibm,slot-connector-type",
 			      slot->connector_type);
 	dt_add_property_cells(np, "ibm,slot-card-desc", slot->card_desc);
 	dt_add_property_cells(np, "ibm,slot-card-mech", slot->card_mech);
 	dt_add_property_cells(np, "ibm,slot-wired-lanes", slot->wired_lanes);
 	dt_add_property_cells(np, "ibm,power-limit", slot->power_limit);

 	if (slot->ops.add_properties)
 		slot->ops.add_properties(slot, np);
 }

 struct pci_slot *pci_slot_alloc(struct phb *phb,
 				struct pci_device *pd)
 {
 	struct pci_slot *slot = NULL;

 	/*
 	 * The function can be used to allocate either PHB slot or normal
 	 * one. For both cases, the @phb should be always valid.
 	 */
 	if (!phb)
 		return NULL;

 	/*
 	 * When @pd is NULL, we're going to create a PHB slot. Otherwise,
 	 * a normal slot will be created. Check if the specified slot
 	 * already exists or not.
 	 */
 	slot = pd ? pd->slot : phb->slot;
 	if (slot) {
 		prlog(PR_ERR, PCI_SLOT_PREFIX "Already exists\n", slot->id);
 		return slot;
 	}

 	/* Allocate memory chunk */
 	slot = zalloc(sizeof(struct pci_slot));
 	if (!slot) {
 		prlog(PR_ERR, "%s: Out of memory\n", __func__);
 		return NULL;
 	}

 	/*
 	 * The polling function sholdn't be overridden by individual
 	 * platforms
 	 */
 	slot->phb = phb;
 	slot->pd = pd;
 	pci_slot_set_state(slot, PCI_SLOT_STATE_NORMAL);
 	slot->power_state = PCI_SLOT_POWER_ON;
 	slot->ops.run_sm = pci_slot_run_sm;
 	slot->ops.prepare_link_change = pci_slot_prepare_link_change;
 	slot->peer_slot = NULL;
 	if (!pd) {
 		slot->id = PCI_PHB_SLOT_ID(phb);
 		phb->slot = slot;
 	} else {
 		slot->id = PCI_SLOT_ID(phb, pd->bdfn);
 		pd->slot = slot;
 	}

 	return slot;
 }

 struct pci_slot *pci_slot_find(uint64_t id)
 {
 	struct phb *phb;
 	struct pci_device *pd;
 	struct pci_slot *slot;
 	uint64_t index;
 	uint16_t bdfn;

 	index = PCI_SLOT_PHB_INDEX(id);
 	phb = pci_get_phb(index);

 	/* PHB slot */
 	if (!(id & PCI_SLOT_ID_PREFIX)) {
 		slot = phb ? phb->slot : NULL;
 		return slot;
 	}

 	/* Normal PCI slot */
 	bdfn = PCI_SLOT_BDFN(id);
 	pd = phb ? pci_find_dev(phb, bdfn) : NULL;
 	slot = pd ? pd->slot : NULL;
 	return slot;
 }

 void pci_slot_add_loc(struct pci_slot *slot,
 			struct dt_node *np, const char *label)
 {
 	char tmp[8], loc_code[LOC_CODE_SIZE];
 	struct pci_device *pd = slot->pd;
 	struct phb *phb = slot->phb;

 	if (!np)
 		return;

 	/* didn't get a real slot label? generate one! */
 	if (!label) {
 		snprintf(tmp, sizeof(tmp), "S%04x%02x", phb->opal_id,
 			pd->secondary_bus);
 		label = tmp;
 	}

 	/* Make a <PHB_LOC_CODE>-<LABEL> pair if we have a PHB loc code */
 	if (phb->base_loc_code) {
 		snprintf(loc_code, sizeof(loc_code), "%s-%s",
 			phb->base_loc_code, label);
 	} else {
 		strncpy(loc_code, label, sizeof(loc_code) - 1);
 		loc_code[LOC_CODE_SIZE - 1] = '\0';
 	}

 	dt_add_property_string(np, "ibm,slot-label", label);
 	dt_add_property_string(np, "ibm,slot-location-code", loc_code);
 }
	// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
	/*
	* PCI Slots
	*
	* Copyright 2013-2019 IBM Corp.
	*/

	#include <skiboot.h>
	#include <opal-msg.h>
	#include <pci-cfg.h>
	#include <pci.h>
	#include <pci-slot.h>

	/* Debugging options */
	#define PCI_SLOT_PREFIX "PCI-SLOT-%016llx "
	#define PCI_SLOT_DBG(s, fmt, a...) \
	prlog(PR_DEBUG, PCI_SLOT_PREFIX fmt, (s)->id, ##a)

	static void pci_slot_prepare_link_change(struct pci_slot *slot, bool up)
	{
	struct phb *phb = slot->phb;
	struct pci_device *pd = slot->pd;
	uint32_t aercap, mask;

	/*
	* Mask the link down and receiver error before the link becomes
	* down. Otherwise, unmask the errors when the link is up.
	*/
	if (pci_has_cap(pd, PCIECAP_ID_AER, true)) {
	aercap = pci_cap(pd, PCIECAP_ID_AER, true);

	/* Mask link surprise down event. The event is always
	* masked when the associated PCI slot supports PCI
	* surprise hotplug. We needn't toggle it when the link
	* bounces caused by reset and just keep it always masked.
	*/
	if (!pd->slot \|\| !pd->slot->surprise_pluggable) {
	pci_cfg_read32(phb, pd->bdfn,
	aercap + PCIECAP_AER_UE_MASK, &mask);
	if (up)
	mask &= ~PCIECAP_AER_UE_MASK_SURPRISE_DOWN;
	else
	mask \|= PCIECAP_AER_UE_MASK_SURPRISE_DOWN;
	pci_cfg_write32(phb, pd->bdfn,
	aercap + PCIECAP_AER_UE_MASK, mask);
	}

	/* Receiver error */
	pci_cfg_read32(phb, pd->bdfn, aercap + PCIECAP_AER_CE_MASK,
	&mask);
	if (up)
	mask &= ~PCIECAP_AER_CE_RECVR_ERR;
	else
	mask \|= PCIECAP_AER_CE_RECVR_ERR;
	pci_cfg_write32(phb, pd->bdfn, aercap + PCIECAP_AER_CE_MASK,
	mask);
	}

	/*
	* We're coming back from reset. We need restore bus ranges
	* and reinitialize the affected bridges and devices.
	*/
	if (up) {
	pci_restore_bridge_buses(phb, pd);
	if (phb->ops->device_init)
	pci_walk_dev(phb, pd, phb->ops->device_init, NULL);
	}
	}

	static int64_t pci_slot_run_sm(struct pci_slot *slot)
	{
	uint64_t now = mftb();
	int64_t ret;

	/* Return remaining timeout if we're still waiting */
	if (slot->delay_tgt_tb &&
	tb_compare(now, slot->delay_tgt_tb) == TB_ABEFOREB)
	return slot->delay_tgt_tb - now;

	slot->delay_tgt_tb = 0;
	switch (slot->state & PCI_SLOT_STATE_MASK) {
	case PCI_SLOT_STATE_LINK:
	ret = slot->ops.poll_link(slot);
	break;
	case PCI_SLOT_STATE_HRESET:
	ret = slot->ops.hreset(slot);
	break;
	case PCI_SLOT_STATE_FRESET:
	ret = slot->ops.freset(slot);
	break;
	case PCI_SLOT_STATE_CRESET:
	ret = slot->ops.creset(slot);
	break;
	default:
	prlog(PR_ERR, PCI_SLOT_PREFIX
	"Invalid state %08x\n", slot->id, slot->state);
	pci_slot_set_state(slot, PCI_SLOT_STATE_NORMAL);
	ret = OPAL_HARDWARE;
	}

	/* Notify about the pci slot state machine completion */
	if (ret <= 0 && slot->ops.completed_sm_run)
	slot->ops.completed_sm_run(slot, ret);

	return ret;
	}

	void pci_slot_add_dt_properties(struct pci_slot *slot,
	struct dt_node *np)
	{
	/* Bail without device node */
	if (!np)
	return;

	dt_add_property_cells(np, "ibm,reset-by-firmware", 1);
	dt_add_property_cells(np, "ibm,slot-pluggable", slot->pluggable);
	dt_add_property_cells(np, "ibm,slot-surprise-pluggable",
	slot->surprise_pluggable);
	if (pci_slot_has_flags(slot, PCI_SLOT_FLAG_BROKEN_PDC))
	dt_add_property_cells(np, "ibm,slot-broken-pdc", 1);

	dt_add_property_cells(np, "ibm,slot-power-ctl", slot->power_ctl);
	dt_add_property_cells(np, "ibm,slot-power-led-ctlled",
	slot->power_led_ctl);
	dt_add_property_cells(np, "ibm,slot-attn-led", slot->attn_led_ctl);
	dt_add_property_cells(np, "ibm,slot-connector-type",
	slot->connector_type);
	dt_add_property_cells(np, "ibm,slot-card-desc", slot->card_desc);
	dt_add_property_cells(np, "ibm,slot-card-mech", slot->card_mech);
	dt_add_property_cells(np, "ibm,slot-wired-lanes", slot->wired_lanes);
	dt_add_property_cells(np, "ibm,power-limit", slot->power_limit);

	if (slot->ops.add_properties)
	slot->ops.add_properties(slot, np);
	}

	struct pci_slot pci_slot_alloc(struct phb phb,
	struct pci_device *pd)
	{
	struct pci_slot *slot = NULL;

	/*
	* The function can be used to allocate either PHB slot or normal
	* one. For both cases, the @phb should be always valid.
	*/
	if (!phb)
	return NULL;

	/*
	* When @pd is NULL, we're going to create a PHB slot. Otherwise,
	* a normal slot will be created. Check if the specified slot
	* already exists or not.
	*/
	slot = pd ? pd->slot : phb->slot;
	if (slot) {
	prlog(PR_ERR, PCI_SLOT_PREFIX "Already exists\n", slot->id);
	return slot;
	}

	/* Allocate memory chunk */
	slot = zalloc(sizeof(struct pci_slot));
	if (!slot) {
	prlog(PR_ERR, "%s: Out of memory\n", __func__);
	return NULL;
	}

	/*
	* The polling function sholdn't be overridden by individual
	* platforms
	*/
	slot->phb = phb;
	slot->pd = pd;
	pci_slot_set_state(slot, PCI_SLOT_STATE_NORMAL);
	slot->power_state = PCI_SLOT_POWER_ON;
	slot->ops.run_sm = pci_slot_run_sm;
	slot->ops.prepare_link_change = pci_slot_prepare_link_change;
	slot->peer_slot = NULL;
	if (!pd) {
	slot->id = PCI_PHB_SLOT_ID(phb);
	phb->slot = slot;
	} else {
	slot->id = PCI_SLOT_ID(phb, pd->bdfn);
	pd->slot = slot;
	}

	return slot;
	}

	struct pci_slot *pci_slot_find(uint64_t id)
	{
	struct phb *phb;
	struct pci_device *pd;
	struct pci_slot *slot;
	uint64_t index;
	uint16_t bdfn;

	index = PCI_SLOT_PHB_INDEX(id);
	phb = pci_get_phb(index);

	/* PHB slot */
	if (!(id & PCI_SLOT_ID_PREFIX)) {
	slot = phb ? phb->slot : NULL;
	return slot;
	}

	/* Normal PCI slot */
	bdfn = PCI_SLOT_BDFN(id);
	pd = phb ? pci_find_dev(phb, bdfn) : NULL;
	slot = pd ? pd->slot : NULL;
	return slot;
	}

	void pci_slot_add_loc(struct pci_slot *slot,
	struct dt_node np, const char label)
	{
	char tmp[8], loc_code[LOC_CODE_SIZE];
	struct pci_device *pd = slot->pd;
	struct phb *phb = slot->phb;

	if (!np)
	return;

	/* didn't get a real slot label? generate one! */
	if (!label) {
	snprintf(tmp, sizeof(tmp), "S%04x%02x", phb->opal_id,
	pd->secondary_bus);
	label = tmp;
	}

	/* Make a <PHB_LOC_CODE>-<LABEL> pair if we have a PHB loc code */
	if (phb->base_loc_code) {
	snprintf(loc_code, sizeof(loc_code), "%s-%s",
	phb->base_loc_code, label);
	} else {
	strncpy(loc_code, label, sizeof(loc_code) - 1);
	loc_code[LOC_CODE_SIZE - 1] = '\0';
	}

	dt_add_property_string(np, "ibm,slot-label", label);
	dt_add_property_string(np, "ibm,slot-location-code", loc_code);
	}