path: root/hw/prd.c

// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
/*
 * PRD: Processor Runtime Diagnostics
 *
 * Copyright 2014-2019 IBM Corp.
 */

#include <skiboot.h>
#include <opal.h>
#include <lock.h>
#include <xscom.h>
#include <chip.h>
#include <opal-msg.h>
#include <fsp.h>
#include <mem_region.h>
#include <prd-fw-msg.h>
#include <hostservices.h>

enum events {
	EVENT_ATTN	= 1 << 0,
	EVENT_OCC_ERROR	= 1 << 1,
	EVENT_OCC_RESET	= 1 << 2,
	EVENT_SBE_PASSTHROUGH = 1 << 3,
	EVENT_FSP_OCC_RESET = 1 << 4,
	EVENT_FSP_OCC_LOAD_START = 1 << 5,
};

static uint8_t events[MAX_CHIPS];
static uint64_t ipoll_status[MAX_CHIPS];
static uint8_t _prd_msg_buf[sizeof(struct opal_prd_msg) +
			    sizeof(struct prd_fw_msg)];
static struct opal_prd_msg *prd_msg = (struct opal_prd_msg *)&_prd_msg_buf;
static struct opal_prd_msg *prd_msg_fsp_req;
static struct opal_prd_msg *prd_msg_fsp_notify;
static bool prd_msg_inuse, prd_active;
static struct dt_node *prd_node;
static bool prd_enabled = false;

/* Locking:
 *
 * The events lock serialises access to the events, ipoll_status,
 * prd_msg_inuse, and prd_active variables.
 *
 * The ipoll_lock protects against concurrent updates to the ipoll registers.
 *
 * The ipoll_lock may be acquired with events_lock held. This order must
 * be preserved.
 */
static struct lock events_lock = LOCK_UNLOCKED;
static struct lock ipoll_lock = LOCK_UNLOCKED;

static uint64_t prd_ipoll_mask_reg;
static uint64_t prd_ipoll_status_reg;
static uint64_t prd_ipoll_mask;

/* PRD registers */
#define PRD_P8_IPOLL_REG_MASK		0x01020013
#define PRD_P8_IPOLL_REG_STATUS		0x01020014
#define PRD_P8_IPOLL_XSTOP		PPC_BIT(0) /* Xstop for host/core/millicode */
#define PRD_P8_IPOLL_RECOV		PPC_BIT(1) /* Recoverable */
#define PRD_P8_IPOLL_SPEC_ATTN		PPC_BIT(2) /* Special attention */
#define PRD_P8_IPOLL_HOST_ATTN		PPC_BIT(3) /* Host attention */
#define PRD_P8_IPOLL_MASK		PPC_BITMASK(0, 3)

#define PRD_P9_IPOLL_REG_MASK		0x000F0033
#define PRD_P9_IPOLL_REG_STATUS		0x000F0034
#define PRD_P9_IPOLL_XSTOP		PPC_BIT(0) /* Xstop for host/core/millicode */
#define PRD_P9_IPOLL_RECOV		PPC_BIT(1) /* Recoverable */
#define PRD_P9_IPOLL_SPEC_ATTN		PPC_BIT(2) /* Special attention */
#define PRD_P9_IPOLL_UNIT_CS		PPC_BIT(3) /* Unit Xstop */
#define PRD_P9_IPOLL_HOST_ATTN		PPC_BIT(4) /* Host attention */
#define PRD_P9_IPOLL_MASK_INTR		PPC_BIT(5) /* Host interrupt */
#define PRD_P9_IPOLL_MASK		PPC_BITMASK(0, 5)

static void send_next_pending_event(void);

static void prd_msg_consumed(void *data, int status)
{
	struct opal_prd_msg *msg = data;
	uint32_t proc;
	int notify_status = OPAL_SUCCESS;
	uint8_t event = 0;

	lock(&events_lock);
	switch (msg->hdr.type) {
	case OPAL_PRD_MSG_TYPE_ATTN:
		proc = be64_to_cpu(msg->attn.proc);

		/* If other ipoll events have been received in the time
		 * between prd_msg creation and consumption, we'll need to
		 * raise a separate ATTN message for those. So, we only
		 * clear the event if we don't have any further ipoll_status
		 * bits.
		 */
		ipoll_status[proc] &= ~be64_to_cpu(msg->attn.ipoll_status);
		if (!ipoll_status[proc])
			event = EVENT_ATTN;

		break;
	case OPAL_PRD_MSG_TYPE_OCC_ERROR:
		proc = be64_to_cpu(msg->occ_error.chip);
		event = EVENT_OCC_ERROR;
		break;
	case OPAL_PRD_MSG_TYPE_OCC_RESET:
		proc = be64_to_cpu(msg->occ_reset.chip);
		event = EVENT_OCC_RESET;
		break;
	case OPAL_PRD_MSG_TYPE_FIRMWARE_RESPONSE:
		if (prd_msg_fsp_req) {
			free(prd_msg_fsp_req);
			prd_msg_fsp_req = NULL;
		}
		break;
	case OPAL_PRD_MSG_TYPE_FIRMWARE_NOTIFY:
		if (prd_msg_fsp_notify) {
			free(prd_msg_fsp_notify);
			prd_msg_fsp_notify = NULL;
		}
		if (status != 0) {
			prlog(PR_DEBUG,
			      "PRD: Failed to send FSP -> HBRT message\n");
			notify_status = FSP_STATUS_GENERIC_ERROR;
		}
		if (platform.prd && platform.prd->msg_response)
			platform.prd->msg_response(notify_status);
		break;
	case OPAL_PRD_MSG_TYPE_SBE_PASSTHROUGH:
		proc = be64_to_cpu(msg->sbe_passthrough.chip);
		event = EVENT_SBE_PASSTHROUGH;
		break;
	case OPAL_PRD_MSG_TYPE_FSP_OCC_RESET:
		proc = be64_to_cpu(msg->occ_reset.chip);
		event = EVENT_FSP_OCC_RESET;
		break;
	case OPAL_PRD_MSG_TYPE_FSP_OCC_LOAD_START:
		proc = be64_to_cpu(msg->occ_reset.chip);
		event = EVENT_FSP_OCC_LOAD_START;
		break;
	default:
		prlog(PR_ERR, "PRD: invalid msg consumed, type: 0x%x\n",
				msg->hdr.type);
	}

	if (event)
		events[proc] &= ~event;
	prd_msg_inuse = false;
	send_next_pending_event();
	unlock(&events_lock);
}

/*
 * OPAL_MSG_PRD interface can handle message size <= OPAL_MSG_FIXED_PARAMS_SIZE.
 * But kernel prd driver had a bug where it will not copy partial data to user
 * space. Use OPAL_MSG_PRD interface only if size is <= sizeof(opal_prg_msg).
 */
static inline int opal_queue_prd_msg(struct opal_prd_msg *msg)
{
	enum opal_msg_type msg_type = OPAL_MSG_PRD2;

	if (be16_to_cpu(msg->hdr.size) <= 0x20)
		msg_type = OPAL_MSG_PRD;

	return _opal_queue_msg(msg_type, msg, prd_msg_consumed,
			       be16_to_cpu(msg->hdr.size), msg);
}

static int populate_ipoll_msg(struct opal_prd_msg *msg, uint32_t proc)
{
	uint64_t ipoll_mask;
	int rc;

	lock(&ipoll_lock);
	rc = xscom_read(proc, prd_ipoll_mask_reg, &ipoll_mask);
	unlock(&ipoll_lock);

	if (rc) {
		prlog(PR_ERR, "PRD: Unable to read ipoll status (chip %d)!\n",
				proc);
		return -1;
	}

	msg->attn.proc = cpu_to_be64(proc);
	msg->attn.ipoll_status = cpu_to_be64(ipoll_status[proc]);
	msg->attn.ipoll_mask = cpu_to_be64(ipoll_mask);
	return 0;
}

static void send_next_pending_event(void)
{
	struct proc_chip *chip;
	uint32_t proc;
	int rc;
	uint8_t event;

	assert(!prd_msg_inuse);

	if (!prd_active)
		return;

	event = 0;

	for_each_chip(chip) {
		proc = chip->id;
		if (events[proc]) {
			event = events[proc];
			break;
		}
	}

	if (!event)
		return;

	prd_msg->token = 0;
	prd_msg->hdr.size = cpu_to_be16(sizeof(*prd_msg));

	if (event & EVENT_ATTN) {
		prd_msg->hdr.type = OPAL_PRD_MSG_TYPE_ATTN;
		populate_ipoll_msg(prd_msg, proc);
	} else if (event & EVENT_OCC_ERROR) {
		prd_msg->hdr.type = OPAL_PRD_MSG_TYPE_OCC_ERROR;
		prd_msg->occ_error.chip = cpu_to_be64(proc);
	} else if (event & EVENT_OCC_RESET) {
		prd_msg->hdr.type = OPAL_PRD_MSG_TYPE_OCC_RESET;
		prd_msg->occ_reset.chip = cpu_to_be64(proc);
		occ_msg_queue_occ_reset();
	} else if (event & EVENT_SBE_PASSTHROUGH) {
		prd_msg->hdr.type = OPAL_PRD_MSG_TYPE_SBE_PASSTHROUGH;
		prd_msg->sbe_passthrough.chip = cpu_to_be64(proc);
	} else if (event & EVENT_FSP_OCC_RESET) {
		prd_msg->hdr.type = OPAL_PRD_MSG_TYPE_FSP_OCC_RESET;
		prd_msg->occ_reset.chip = cpu_to_be64(proc);
	} else if (event & EVENT_FSP_OCC_LOAD_START) {
		prd_msg->hdr.type = OPAL_PRD_MSG_TYPE_FSP_OCC_LOAD_START;
		prd_msg->occ_reset.chip = cpu_to_be64(proc);
	}

	/*
	 * We always need to handle PSI interrupts, but if the is PRD is
	 * disabled then we shouldn't propagate PRD events to the host.
	 */
	if (prd_enabled) {
		rc = opal_queue_prd_msg(prd_msg);
		if (!rc)
			prd_msg_inuse = true;
	}
}

static void __prd_event(uint32_t proc, uint8_t event)
{
	events[proc] |= event;
	if (!prd_msg_inuse)
		send_next_pending_event();
}

static void prd_event(uint32_t proc, uint8_t event)
{
	lock(&events_lock);
	__prd_event(proc, event);
	unlock(&events_lock);
}

static int __ipoll_update_mask(uint32_t proc, bool set, uint64_t bits)
{
	uint64_t mask;
	int rc;

	rc = xscom_read(proc, prd_ipoll_mask_reg, &mask);
	if (rc)
		return rc;

	if (set)
		mask |= bits;
	else
		mask &= ~bits;

	return xscom_write(proc, prd_ipoll_mask_reg, mask);
}

static int ipoll_record_and_mask_pending(uint32_t proc)
{
	uint64_t status;
	int rc;

	lock(&ipoll_lock);
	rc = xscom_read(proc, prd_ipoll_status_reg, &status);
	status &= prd_ipoll_mask;
	if (!rc)
		__ipoll_update_mask(proc, true, status);
	unlock(&ipoll_lock);

	if (!rc)
		ipoll_status[proc] |= status;

	return rc;
}

/* Entry point for interrupts */
void prd_psi_interrupt(uint32_t proc)
{
	int rc;

	lock(&events_lock);

	rc = ipoll_record_and_mask_pending(proc);
	if (rc)
		prlog(PR_ERR, "PRD: Failed to update IPOLL mask\n");

	__prd_event(proc, EVENT_ATTN);

	unlock(&events_lock);
}

void prd_tmgt_interrupt(uint32_t proc)
{
	prd_event(proc, EVENT_OCC_ERROR);
}

void prd_occ_reset(uint32_t proc)
{
	prd_event(proc, EVENT_OCC_RESET);
}

void prd_fsp_occ_reset(uint32_t proc)
{
	prd_event(proc, EVENT_FSP_OCC_RESET);
}

void prd_sbe_passthrough(uint32_t proc)
{
	prd_event(proc, EVENT_SBE_PASSTHROUGH);
}

void prd_fsp_occ_load_start(uint32_t proc)
{
	prd_event(proc, EVENT_FSP_OCC_LOAD_START);
}

void prd_fw_resp_fsp_response(int status)
{
	struct prd_fw_msg *fw_resp;
	uint64_t fw_resp_len_old;
	int rc;
	uint16_t hdr_size;

	lock(&events_lock);

	/* In case of failure, return code is passed via generic_resp */
	if (status != 0) {
		fw_resp = (struct prd_fw_msg *)prd_msg_fsp_req->fw_resp.data;
		fw_resp->type = cpu_to_be64(PRD_FW_MSG_TYPE_RESP_GENERIC);
		fw_resp->generic_resp.status = cpu_to_be64(status);

		fw_resp_len_old = be64_to_cpu(prd_msg_fsp_req->fw_resp.len);
		prd_msg_fsp_req->fw_resp.len = cpu_to_be64(PRD_FW_MSG_BASE_SIZE +
						 sizeof(fw_resp->generic_resp));

		/* Update prd message size */
		hdr_size = be16_to_cpu(prd_msg_fsp_req->hdr.size);
		hdr_size -= fw_resp_len_old;
		hdr_size += be64_to_cpu(prd_msg_fsp_req->fw_resp.len);
		prd_msg_fsp_req->hdr.size = cpu_to_be16(hdr_size);
	}

	rc = opal_queue_prd_msg(prd_msg_fsp_req);
	if (!rc)
		prd_msg_inuse = true;
	unlock(&events_lock);
}

int prd_hbrt_fsp_msg_notify(void *data, u32 dsize)
{
	struct prd_fw_msg *fw_notify;
	int size, fw_notify_size;
	int rc = FSP_STATUS_GENERIC_ERROR;

	if (!prd_enabled) {
		prlog(PR_NOTICE, "PRD: %s: PRD daemon is not ready\n",
		      __func__);
		return rc;
	}

	/* Calculate prd message size */
	fw_notify_size = PRD_FW_MSG_BASE_SIZE + dsize;
	size =  sizeof(prd_msg->hdr) + sizeof(prd_msg->token) +
		sizeof(prd_msg->fw_notify) + fw_notify_size;

	if (size > OPAL_PRD_MSG_SIZE_MAX) {
		prlog(PR_DEBUG, "PRD: FSP - HBRT notify message size (0x%x)"
		      " is bigger than prd interface can handle\n", size);
		return rc;
	}

	lock(&events_lock);

	/* FSP - HBRT messages are serialized */
	if (prd_msg_fsp_notify) {
		prlog(PR_DEBUG, "PRD: FSP - HBRT notify message is busy\n");
		goto unlock_events;
	}

	/* Handle message allocation */
	prd_msg_fsp_notify = zalloc(size);
	if (!prd_msg_fsp_notify) {
		prlog(PR_DEBUG,
		      "PRD: %s: Failed to allocate memory.\n", __func__);
		goto unlock_events;
	}

	prd_msg_fsp_notify->hdr.type = OPAL_PRD_MSG_TYPE_FIRMWARE_NOTIFY;
	prd_msg_fsp_notify->hdr.size = cpu_to_be16(size);
	prd_msg_fsp_notify->token = 0;
	prd_msg_fsp_notify->fw_notify.len = cpu_to_be64(fw_notify_size);
	fw_notify = (void *)prd_msg_fsp_notify->fw_notify.data;
	fw_notify->type = cpu_to_be64(PRD_FW_MSG_TYPE_HBRT_FSP);
	memcpy(&(fw_notify->mbox_msg), data, dsize);

	if (!prd_active) {
		// save the message, we'll deliver it when prd starts
		rc = FSP_STATUS_BUSY;
		goto unlock_events;
	}

	rc = opal_queue_prd_msg(prd_msg_fsp_notify);
	if (!rc)
		prd_msg_inuse = true;

unlock_events:
	unlock(&events_lock);
	return rc;
}

/* incoming message handlers */
static int prd_msg_handle_attn_ack(struct opal_prd_msg *msg)
{
	int rc;

	lock(&ipoll_lock);
	rc = __ipoll_update_mask(be64_to_cpu(msg->attn_ack.proc), false,
			be64_to_cpu(msg->attn_ack.ipoll_ack) & prd_ipoll_mask);
	unlock(&ipoll_lock);

	if (rc)
		prlog(PR_ERR, "PRD: Unable to unmask ipoll!\n");

	return rc;
}

static int prd_msg_handle_init(struct opal_prd_msg *msg)
{
	struct proc_chip *chip;

	lock(&ipoll_lock);
	for_each_chip(chip) {
		__ipoll_update_mask(chip->id, false,
			be64_to_cpu(msg->init.ipoll) & prd_ipoll_mask);
	}
	unlock(&ipoll_lock);

	/* we're transitioning from inactive to active; send any pending tmgt
	 * interrupts */
	lock(&events_lock);
	prd_active = true;

	if (prd_msg_fsp_notify) {
		if (!opal_queue_prd_msg(prd_msg_fsp_notify))
			prd_msg_inuse = true;
	}
	if (!prd_msg_inuse)
		send_next_pending_event();
	unlock(&events_lock);

	return OPAL_SUCCESS;
}

static int prd_msg_handle_fini(void)
{
	struct proc_chip *chip;

	lock(&events_lock);
	prd_active = false;
	unlock(&events_lock);

	lock(&ipoll_lock);
	for_each_chip(chip) {
		__ipoll_update_mask(chip->id, true, prd_ipoll_mask);
	}
	unlock(&ipoll_lock);

	return OPAL_SUCCESS;
}

static int prd_msg_handle_firmware_req(struct opal_prd_msg *msg)
{
	unsigned long fw_req_len, fw_resp_len, data_len;
	struct prd_fw_msg *fw_req, *fw_resp;
	int rc;
	uint64_t resp_msg_size;

	fw_req_len = be64_to_cpu(msg->fw_req.req_len);
	fw_resp_len = be64_to_cpu(msg->fw_req.resp_len);
	fw_req = (struct prd_fw_msg *)msg->fw_req.data;

	/* do we have a full firmware message? */
	if (fw_req_len < sizeof(struct prd_fw_msg))
		return -EINVAL;

	/* does the total (outer) PRD message len provide enough data for the
	 * claimed (inner) FW message?
	 */
	if (be16_to_cpu(msg->hdr.size) < fw_req_len +
			offsetof(struct opal_prd_msg, fw_req.data))
		return -EINVAL;

	/* is there enough response buffer for a base response? Type-specific
	 * responses may be larger, but anything less than BASE_SIZE is
	 * invalid. */
	if (fw_resp_len < PRD_FW_MSG_BASE_SIZE)
		return -EINVAL;

	/* prepare a response message. */
	lock(&events_lock);
	prd_msg_inuse = true;
	prd_msg->token = 0;
	prd_msg->hdr.type = OPAL_PRD_MSG_TYPE_FIRMWARE_RESPONSE;
	fw_resp = (void *)prd_msg->fw_resp.data;

	switch (be64_to_cpu(fw_req->type)) {
	case PRD_FW_MSG_TYPE_REQ_NOP:
		fw_resp->type = cpu_to_be64(PRD_FW_MSG_TYPE_RESP_NOP);
		prd_msg->fw_resp.len = cpu_to_be64(PRD_FW_MSG_BASE_SIZE);
		prd_msg->hdr.size = cpu_to_be16(sizeof(*prd_msg));
		rc = 0;
		break;
	case PRD_FW_MSG_TYPE_ERROR_LOG:
		if (platform.prd == NULL ||
		    platform.prd->send_error_log == NULL) {
			rc = OPAL_UNSUPPORTED;
			break;
		}

		rc = platform.prd->send_error_log(be32_to_cpu(fw_req->errorlog.plid),
						  be32_to_cpu(fw_req->errorlog.size),
						  fw_req->errorlog.data);
		/* Return generic response to HBRT */
		fw_resp->type = cpu_to_be64(PRD_FW_MSG_TYPE_RESP_GENERIC);
		fw_resp->generic_resp.status = cpu_to_be64(rc);
		prd_msg->fw_resp.len = cpu_to_be64(PRD_FW_MSG_BASE_SIZE +
						 sizeof(fw_resp->generic_resp));
		prd_msg->hdr.size = cpu_to_be16(sizeof(*prd_msg));
		rc = 0;
		break;
	case PRD_FW_MSG_TYPE_HBRT_FSP:
		if (platform.prd == NULL ||
		    platform.prd->send_hbrt_msg == NULL) {
			rc = OPAL_UNSUPPORTED;
			break;
		}

		/*
		 * HBRT -> FSP messages are serialized. Just to be sure check
		 * whether fsp_req message is free or not.
		 */
		if (prd_msg_fsp_req) {
			prlog(PR_DEBUG, "PRD: HBRT - FSP message is busy\n");
			rc = OPAL_BUSY;
			break;
		}

		/*
		 * FSP interface doesn't tell us the response data size.
		 * Hence pass response length = request length.
		 */
		resp_msg_size = sizeof(msg->hdr) + sizeof(msg->token) +
			sizeof(msg->fw_resp) + fw_req_len;

		if (resp_msg_size > OPAL_PRD_MSG_SIZE_MAX) {
			prlog(PR_DEBUG, "PRD: HBRT - FSP response size (0x%llx)"
			      " is bigger than prd interface can handle\n",
			      resp_msg_size);
			rc = OPAL_INTERNAL_ERROR;
			break;
		}

		/*
		 * We will use fsp_queue_msg() to pass HBRT data to FSP.
		 * We cannot directly map kernel passed data as kernel
		 * will release the memory as soon as we return the control.
		 * Also FSP uses same memory to pass response to HBRT. Hence
		 * lets copy data to local memory. Then pass this memory to
		 * FSP via TCE mapping.
		 */
		prd_msg_fsp_req = zalloc(resp_msg_size);
		if (!prd_msg_fsp_req) {
			prlog(PR_DEBUG, "PRD: Failed to allocate memory "
			      "for HBRT - FSP message\n");
			rc = OPAL_RESOURCE;
			break;
		}

		/* Update message header */
		prd_msg_fsp_req->hdr.type = OPAL_PRD_MSG_TYPE_FIRMWARE_RESPONSE;
		prd_msg_fsp_req->hdr.size = cpu_to_be16(resp_msg_size);
		prd_msg_fsp_req->token = 0;
		prd_msg_fsp_req->fw_resp.len = cpu_to_be64(fw_req_len);

		/* copy HBRT data to local memory */
		fw_resp = (struct prd_fw_msg *)prd_msg_fsp_req->fw_resp.data;
		memcpy(fw_resp, fw_req, fw_req_len);

		/* Update response type */
		fw_resp->type = cpu_to_be64(PRD_FW_MSG_TYPE_HBRT_FSP);

		/* Get MBOX message size */
		data_len = fw_req_len - PRD_FW_MSG_BASE_SIZE;

		/* We have to wait until FSP responds */
		prd_msg_inuse = false;
		/* Unlock to avoid recursive lock issue */
		unlock(&events_lock);

		/* Send message to FSP */
		rc = platform.prd->send_hbrt_msg(&(fw_resp->mbox_msg), data_len);

		/*
		 * Callback handler from hservice_send_hbrt_msg will take
		 * care of sending response to HBRT. So just send return
		 * code to Linux.
		 */
		if (rc == OPAL_SUCCESS)
			return rc;

		lock(&events_lock);
		if (prd_msg_fsp_req) {
			free(prd_msg_fsp_req);
			prd_msg_fsp_req = NULL;
		}
		break;
	default:
		prlog(PR_DEBUG, "PRD: Unsupported fw_request type : 0x%llx\n",
		      be64_to_cpu(fw_req->type));
		rc = -ENOSYS;
	}

	if (!rc) {
		rc = opal_queue_prd_msg(prd_msg);
		if (rc)
			prd_msg_inuse = false;
	} else {
		prd_msg_inuse = false;
	}

	unlock(&events_lock);

	return rc;
}

/* Entry from the host above */
static int64_t opal_prd_msg(struct opal_prd_msg *msg)
{
	int rc;

	/* fini is a little special: the kernel (which may not have the entire
	 * opal_prd_msg definition) can send a FINI message, so we don't check
	 * the full size */
	if (be16_to_cpu(msg->hdr.size) >= sizeof(struct opal_prd_msg_header) &&
			msg->hdr.type == OPAL_PRD_MSG_TYPE_FINI)
		return prd_msg_handle_fini();

	if (be16_to_cpu(msg->hdr.size) < sizeof(*msg))
		return OPAL_PARAMETER;

	switch (msg->hdr.type) {
	case OPAL_PRD_MSG_TYPE_INIT:
		rc = prd_msg_handle_init(msg);
		break;
	case OPAL_PRD_MSG_TYPE_ATTN_ACK:
		rc = prd_msg_handle_attn_ack(msg);
		break;
	case OPAL_PRD_MSG_TYPE_OCC_RESET_NOTIFY:
		rc = occ_msg_queue_occ_reset();
		break;
	case OPAL_PRD_MSG_TYPE_FIRMWARE_REQUEST:
		rc = prd_msg_handle_firmware_req(msg);
		break;
	case OPAL_PRD_MSG_TYPE_FSP_OCC_RESET_STATUS:
		if (platform.prd == NULL ||
		    platform.prd->fsp_occ_reset_status == NULL) {
			rc = OPAL_UNSUPPORTED;
			break;
		}
		rc = platform.prd->fsp_occ_reset_status(
			be64_to_cpu(msg->fsp_occ_reset_status.chip),
			be64_to_cpu(msg->fsp_occ_reset_status.status));
		break;
	case OPAL_PRD_MSG_TYPE_CORE_SPECIAL_WAKEUP:
		if (platform.prd == NULL ||
		    platform.prd->wakeup == NULL) {
			rc = OPAL_UNSUPPORTED;
			break;
		}
		rc = platform.prd->wakeup(be32_to_cpu(msg->spl_wakeup.core),
					  be32_to_cpu(msg->spl_wakeup.mode));
		break;
	case OPAL_PRD_MSG_TYPE_FSP_OCC_LOAD_START_STATUS:
		if (platform.prd == NULL ||
		    platform.prd->fsp_occ_load_start_status == NULL) {
			rc = OPAL_UNSUPPORTED;
			break;
		}
		rc = platform.prd->fsp_occ_load_start_status(
			be64_to_cpu(msg->fsp_occ_reset_status.chip),
			be64_to_cpu(msg->fsp_occ_reset_status.status));
		break;
	default:
		prlog(PR_DEBUG, "PRD: Unsupported prd message type : 0x%x\n",
		      msg->hdr.type);
		rc = OPAL_UNSUPPORTED;
	}

	return rc;
}


/*
 * Initialise the Opal backend for the PRD daemon. This must be called from
 * platform probe or init function.
 */
void prd_init(void)
{
	struct proc_chip *chip;

	switch (proc_gen) {
	case proc_gen_p8:
		prd_ipoll_mask_reg = PRD_P8_IPOLL_REG_MASK;
		prd_ipoll_status_reg = PRD_P8_IPOLL_REG_STATUS;
		prd_ipoll_mask = PRD_P8_IPOLL_MASK;
		break;
	case proc_gen_p9:
		prd_ipoll_mask_reg = PRD_P9_IPOLL_REG_MASK;
		prd_ipoll_status_reg = PRD_P9_IPOLL_REG_STATUS;
		prd_ipoll_mask = PRD_P9_IPOLL_MASK;
		break;
	case proc_gen_p10: /* IPOLL regs are the same for p9 and p10 */
		prd_ipoll_mask_reg = PRD_P9_IPOLL_REG_MASK;
		prd_ipoll_status_reg = PRD_P9_IPOLL_REG_STATUS;
		prd_ipoll_mask = PRD_P9_IPOLL_MASK;
		break;
	default:
		assert(0);
	}

	/* mask everything */
	lock(&ipoll_lock);
	for_each_chip(chip) {
		__ipoll_update_mask(chip->id, true, prd_ipoll_mask);
	}
	unlock(&ipoll_lock);

	prd_enabled = true;
	opal_register(OPAL_PRD_MSG, opal_prd_msg, 1);

	prd_node = dt_new(opal_node, "diagnostics");
	dt_add_property_strings(prd_node, "compatible", "ibm,opal-prd");
}

void prd_register_reserved_memory(void)
{
	struct mem_region *region;

	if (!prd_node)
		return;

	lock(&mem_region_lock);
	for (region = mem_region_next(NULL); region;
			region = mem_region_next(region)) {

		if (region->type != REGION_FW_RESERVED)
			continue;

		if (!region->node)
			continue;

		if (!dt_find_property(region->node, "ibm,prd-label")) {
			dt_add_property_string(region->node, "ibm,prd-label",
					region->name);
		}
	}
	unlock(&mem_region_lock);
}