pfe_ctrl/pfe_hif_lib.c

#include <linux/version.h>
#include <asm/system.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>
#include <linux/sched.h>
#include <linux/skbuff.h>
#include <linux/moduleparam.h>
#include <linux/cpu.h>

#include "pfe_mod.h"
#include "pfe_hif.h"
#include "pfe_hif_lib.h"
#include "pfe_ctrl_hal.h"


unsigned int lro_mode = 0;
unsigned int page_mode = 0;
module_param(lro_mode, uint, S_IRUGO);
MODULE_PARM_DESC(lro_mode,
                 "0: disable lro support(default), 1: enable lro support, skb data is kept in pages, class is configured in toe mode");
unsigned int tx_qos = 0;
module_param(tx_qos, uint, S_IRUGO);
MODULE_PARM_DESC(tx_qos,
                 "0: disable tx qos (default), 1: enable tx qos, guarantee no packet drop at TMU level, only works if forwarding is disabled");
unsigned int pfe_pkt_size;
unsigned int pfe_pkt_headroom;


/** @pfe_hal_lib.c.
 * Common functions used by HIF client drivers
 */

/*HIF shared memory Global variable */
struct hif_shm ghif_shm;

/* TMU tx transmitted packets counter, 1 per TMU */
unsigned int TMU_DMEM_SH(tx_trans)[EMAC_TXQ_CNT];

/* Cleanup the HIF shared memory, release HIF rx_buffer_pool.
 * This function should be called after pfe_hif_exit
 *
 * @param[in] hif_shm		Shared memory address location in DDR
 */
static void pfe_hif_shm_clean(struct hif_shm *hif_shm)
{
	int i;
	void *pkt;

	for (i = 0; i < hif_shm->rx_buf_pool_cnt; i++) {
		pkt = hif_shm->rx_buf_pool[i];
		if (pkt) {
			hif_shm->rx_buf_pool[i] = NULL;
			pkt -= pfe_pkt_headroom;

			if (page_mode)
				free_page((unsigned long)pkt);
			else
				kfree(pkt);
		}
	}
}

/* Initialize shared memory used between HIF driver and clients, 
 * allocate rx_buffer_pool required for HIF Rx descriptors.
 * This function should be called before initializing HIF driver.
 *
 * @param[in] hif_shm		Shared memory address location in DDR
 * @rerurn			0 - on succes, <0 on fail to initialize
 */
static int pfe_hif_shm_init(struct hif_shm *hif_shm)
{
	int i;
	void *pkt;

	memset(hif_shm, 0, sizeof(struct hif_shm));
	hif_shm->rx_buf_pool_cnt = HIF_RX_DESC_NT;

	for (i = 0; i < hif_shm->rx_buf_pool_cnt; i++) {
		if (page_mode)
			pkt = (void *)__get_free_page(GFP_KERNEL | GFP_DMA_PFE);
		else
			pkt = kmalloc(PFE_BUF_SIZE, GFP_KERNEL | GFP_DMA_PFE);

		if (pkt)
			hif_shm->rx_buf_pool[i] = pkt + pfe_pkt_headroom;
		else
			goto err0;
	}

	return 0;

err0:
	printk(KERN_ERR "%s Low memory\n", __func__);
	pfe_hif_shm_clean(hif_shm);
	return -ENOMEM;
}

/*This function sends indication to HIF driver 
 *
 * @param[in] hif	hif context
 **/
static void hif_lib_indicate_hif(struct pfe_hif *hif, int req, int data1, int data2)
{
	//TODO : If we separate HIF and HIF LIB, then send req and data through shared memory.

	hif_process_client_req(hif, req, data1, data2);
}

/** hif_lib_set_rx_cpu_affinity
 *
 * @param[in] client	Client control block.
 * @param[in] cpu_id	cpu number.
 */
void hif_lib_set_rx_cpu_affinity(struct hif_client_s *client, int cpu_id)
{
	spin_lock_bh(&pfe->hif.lock);


	if (cpu_id < 0) {
		printk(KERN_INFO "%s:Client (%d) and HIF Rx processing will use same cpu\n", __func__, client->id);
		client->user_cpu_id = client->cpu_id = cpu_id;
	}
	else if ( cpu_online(cpu_id)) {
		printk(KERN_INFO "%s:Client (%d) rx processing is moved to cpu#%d\n", __func__, client->id, cpu_id);
		client->user_cpu_id = client->cpu_id = cpu_id;
	}
	else {
		client->user_cpu_id = cpu_id;
		printk(KERN_INFO "%s : CPU (%d) is offline, applied automatically after cpu online\n", __func__, cpu_id);
	}
	spin_unlock_bh(&pfe->hif.lock);
}

/** hif_lib_load_balance
 *
 */
static void hif_lib_load_balance(void *data)
{
	int cl_id = (u32)data & 0xffff;
	int qno = ((u32)data >> 16) & 0xff;
	int event_type = ((u32)data >> 24) & 0xff;
	struct hif_client_s *client = pfe->hif_client[cl_id];

	client->event_handler(client->priv, event_type, qno);
}

void hif_lib_indicate_client(int client_id, int event_type, int qno)
{
	struct hif_client_s *client = pfe->hif_client[client_id];

	/*
	 * TODO : Right now, all events are queue number based. So we are masking events per queue 
	 *        basis. Later if we add any events those do not depend on queue number, then we may
	 *	  may need may need to add masking per event.
	 */
	if (!client || (event_type >= HIF_EVENT_MAX) || (qno >= HIF_CLIENT_QUEUES_MAX) )
		return;

	if (!test_and_set_bit(qno, &client->queue_mask[event_type])) {

#if defined(CONFIG_SMP) && (NR_CPUS > 1)
		if ((event_type == EVENT_RX_PKT_IND) && ((client->cpu_id != smp_processor_id()) && (client->cpu_id >= 0)))
			if(!smp_call_function_single(client->cpu_id,  hif_lib_load_balance, (void *)((event_type << 24) | (qno << 16) | client_id), 0))
				return;

#endif
		client->event_handler(client->priv, event_type, qno);
	}

}


/*This function releases Rx queue descriptors memory and pre-filled buffers
 *
 * @param[in] client	hif_client context
 */
static void hif_lib_client_release_rx_buffers(struct hif_client_s *client)
{
	struct rx_queue_desc *desc;
	int qno, ii;
	void *buf;

	for (qno = 0; qno < client->rx_qn; qno++) {
		desc = client->rx_q[qno].base;

		for (ii = 0; ii < client->rx_q[qno].size; ii++) {
			buf = (void *)desc->data;
			if (buf) {
				buf -= pfe_pkt_headroom;

				if (page_mode)
					free_page((unsigned long)buf);
				else
					kfree(buf);

				desc->ctrl = 0;
			}

			desc++;
		}
	}

	kfree(client->rx_qbase);
}


/*This function allocates memory for the rxq descriptors and pre-fill rx queues
 * with buffers.
 * @param[in] client	client context
 * @param[in] q_size	size of the rxQ, all queues are of same size
 */
static int hif_lib_client_init_rx_buffers(struct hif_client_s *client, int q_size)
{
	struct rx_queue_desc *desc;
	struct hif_client_rx_queue *queue;
	int ii, qno;

	/*Allocate memory for the client queues */
	client->rx_qbase = kzalloc(client->rx_qn * q_size * sizeof(struct rx_queue_desc), GFP_KERNEL);
	if (!client->rx_qbase){
		goto err;
	}

	for (qno = 0; qno < client->rx_qn; qno++) {
		queue = &client->rx_q[qno];

		queue->base = client->rx_qbase + qno * q_size * sizeof(struct rx_queue_desc);
		queue->size = q_size;
		queue->read_idx = 0;
		queue->write_idx = 0;

		dbg_print_info("rx queue: %d, base: %p, size: %d \n", qno, queue->base, queue->size);
	}

	for (qno = 0; qno < client->rx_qn; qno++) {
		queue = &client->rx_q[qno];
		desc = queue->base;

		for (ii = 0; ii < queue->size; ii++) {
			desc->ctrl = CL_DESC_BUF_LEN(pfe_pkt_size) | CL_DESC_OWN;
			desc++;
		}
	}

	return 0;

err:
	return 1;
}

#define inc_cl_idx(idxname) idxname = (idxname+1) & (queue->size-1)

static void hif_lib_client_cleanup_tx_queue(struct hif_client_tx_queue *queue)
{
	dbg_print_info( "%s\n", __func__);

	/* Check if there are any pending packets. Client must flush the tx queues
	before unregistering, by calling by calling hif_lib_tx_get_next_complete() */
	/* Hif no longer calls since we are no longer registered */

	if (queue->tx_pending)
		printk(KERN_ERR "%s: pending transmit packets\n", __func__);
}

static void hif_lib_client_release_tx_buffers(struct hif_client_s *client)
{
	int qno;

	dbg_print_info("%s\n", __func__);

	for (qno = 0; qno < client->tx_qn; qno++) {
		hif_lib_client_cleanup_tx_queue(&client->tx_q[qno]);
	}

	kfree(client->tx_qbase);
}

static int hif_lib_client_init_tx_buffers(struct hif_client_s *client, int q_size)
{
	struct hif_client_tx_queue *queue;
	int qno;

	client->tx_qbase = kzalloc(client->tx_qn * q_size * sizeof(struct tx_queue_desc), GFP_KERNEL);
	if (!client->tx_qbase) {
		return 1;
	}

	for (qno = 0; qno < client->tx_qn; qno++) {
		queue = &client->tx_q[qno];

		queue->base = client->tx_qbase + qno * q_size * sizeof(struct tx_queue_desc);
		queue->size = q_size;
		queue->read_idx = 0;
		queue->write_idx = 0;
		queue->tx_pending = 0;

		dbg_print_info("tx queue: %d, base: %p, size: %d \n", qno, queue->base, queue->size);
	}

	return 0;
}

static int hif_lib_event_dummy( void *priv, int event_type, int qno)
{
	return 0;
}

int hif_lib_client_register(struct hif_client_s *client)
{
	struct hif_shm *hif_shm;
	struct hif_client_shm *client_shm;
	int err, i;
//	int loop_cnt = 0;

	dbg_print_info("%s\n", __func__);

	spin_lock_bh(&pfe->hif.lock);
	if (!(client->pfe) || (client->id >= HIF_CLIENTS_MAX) || (pfe->hif_client[client->id])) {
		err = -EINVAL;
		goto err;
	}

	hif_shm = client->pfe->hif.shm;

	if (hif_lib_client_init_rx_buffers(client, client->rx_qsize)) {
		err = -ENOMEM;
		goto err_rx;
	}

	if (hif_lib_client_init_tx_buffers(client, client->tx_qsize)) {
		err = -ENOMEM;
		goto err_tx;
	}

	if (!client->event_handler) 
		client->event_handler = hif_lib_event_dummy;

	/*Initialize client specific shared memory */
	client_shm = (struct hif_client_shm *)&hif_shm->client[client->id];
	client_shm->rx_qbase = (u32)client->rx_qbase;
	client_shm->rx_qsize = client->rx_qsize;
	client_shm->tx_qbase = (u32)client->tx_qbase;
	client_shm->tx_qsize = client->tx_qsize;
	client_shm->ctrl = (client->tx_qn << CLIENT_CTRL_TX_Q_CNT_OFST) | (client->rx_qn << CLIENT_CTRL_RX_Q_CNT_OFST);
//	spin_lock_init(&client->rx_lock);

	for (i = 0; i < HIF_EVENT_MAX; i++) {
		client->queue_mask[i] = 0; /* By default all events are unmasked */
	}

	/*Indicate to HIF driver*/
	hif_lib_indicate_hif(&pfe->hif, REQUEST_CL_REGISTER, client->id, 0);

	dbg_print_info("%s: client: %p, client_id: %d, tx_qsize: %d, rx_qsize: %d\n",
			__func__, client, client->id, client->tx_qsize, client->rx_qsize);

	client->cpu_id = -1;

	pfe->hif_client[client->id] = client;
	spin_unlock_bh(&pfe->hif.lock);

	/*This function need to be called with out holding hif.lock */
	hif_lib_set_rx_cpu_affinity(client, client->user_cpu_id);

	return 0;

err_tx:
	hif_lib_client_release_rx_buffers(client);

err_rx:
err:
	spin_unlock_bh(&pfe->hif.lock);
	return err;
}

int hif_lib_client_unregister(struct hif_client_s *client)
{
	struct pfe *pfe = client->pfe;
	u32 client_id = client->id;

	printk(KERN_INFO "%s : client: %p, client_id: %d, txQ_depth: %d, rxQ_depth: %d\n",
			__func__, client, client->id, client->tx_qsize, client->rx_qsize);


	spin_lock_bh(&pfe->hif.lock);
	hif_lib_indicate_hif(&pfe->hif, REQUEST_CL_UNREGISTER, client->id, 0);

	hif_lib_client_release_tx_buffers(client);
	hif_lib_client_release_rx_buffers(client);
	pfe->hif_client[client_id] = NULL;
	spin_unlock_bh(&pfe->hif.lock);

	return 0;
}

int hif_lib_event_handler_start(struct hif_client_s *client, int event, int qno)
{
	struct hif_client_rx_queue *queue = &client->rx_q[qno];
	struct rx_queue_desc *desc = queue->base + queue->read_idx;

	if ((event >= HIF_EVENT_MAX) || ( qno >= HIF_CLIENT_QUEUES_MAX)) {
		dbg_print_info("%s: Unsupported event : %d  queue number : %d\n", __func__, event, qno);
		return -1;
	}

	test_and_clear_bit(qno, &client->queue_mask[event]);

	switch (event) {
	case EVENT_RX_PKT_IND:
		if (!(desc->ctrl & CL_DESC_OWN))
			 hif_lib_indicate_client(client->id, EVENT_RX_PKT_IND, qno);
		break;

	case EVENT_HIGH_RX_WM:
	case EVENT_TXDONE_IND:
	default:
		break;
	}

	return 0;
}


/*This function gets one packet from the specified client queue
 * It also refill the rx buffer */
void *hif_lib_receive_pkt(struct hif_client_s *client, int qno, int *len, int *ofst, unsigned int *rx_ctrl, unsigned int *desc_ctrl, void **priv_data)
{
	struct hif_client_rx_queue *queue = &client->rx_q[qno];
	struct rx_queue_desc *desc;
	void *pkt = NULL;

	//printk(KERN_INFO "%s\n", __func__);
#if defined(CONFIG_PLATFORM_EMULATION)
	printk(KERN_INFO "%s:qno:%d cid:%d desc:%p rdidx:%d \n", 
			__func__, qno, client->id, desc, 
			queue->read_idx);
#endif

	/* Following lock is to protect rx queue access from, hif_lib_event_handler_start.
	 * In general below lock is not required, because hif_lib_xmit_pkt and
	 * hif_lib_event_handler_start are called from napi poll and which is not 
	 * re-entrant. But if some client use in different way this lock is required.
	 */
	//spin_lock_irqsave(&client->rx_lock, flags);
	desc = queue->base + queue->read_idx;
	if (!(desc->ctrl & CL_DESC_OWN)) {
		pkt = desc->data - pfe_pkt_headroom;

		*rx_ctrl = desc->client_ctrl;
		*desc_ctrl = desc->ctrl;

		if (desc->ctrl & CL_DESC_FIRST) {
			u16 size = *rx_ctrl >> HIF_CTRL_RX_OFFSET_OFST;

			if (size) {
				*len = CL_DESC_BUF_LEN(desc->ctrl) - PFE_PKT_HEADER_SZ - size;
				*ofst = pfe_pkt_headroom + PFE_PKT_HEADER_SZ + size;
				*priv_data = desc->data + PFE_PKT_HEADER_SZ;
			} else {
				*len = CL_DESC_BUF_LEN(desc->ctrl) - PFE_PKT_HEADER_SZ;
				*ofst = pfe_pkt_headroom + PFE_PKT_HEADER_SZ;
				*priv_data = NULL;
			}

			if(*rx_ctrl & HIF_CTRL_RX_WIFI_HEADROOM) {
				/* PFE inserts empty head room for WiFi Tx packets */
				*ofst += PFE_WIFI_PKT_HEADROOM;
				*len -= PFE_WIFI_PKT_HEADROOM;
				if(priv_data)
					priv_data += PFE_WIFI_PKT_HEADROOM;
			}
		} else {
			*len = CL_DESC_BUF_LEN(desc->ctrl);
			*ofst = pfe_pkt_headroom;
		}

		desc->data = NULL; // Needed so we don't free a buffer/page twice on module_exit
		smp_wmb();

		desc->ctrl = CL_DESC_BUF_LEN(pfe_pkt_size) | CL_DESC_OWN;
		inc_cl_idx(queue->read_idx);
	}

	//spin_unlock_irqrestore(&client->rx_lock, flags);
	return pkt;
}

void __hif_lib_xmit_tso_hdr(struct hif_client_s *client, unsigned int qno, u32 client_ctrl, unsigned int ip_off,
				unsigned int ip_id, unsigned int ip_len, unsigned int tcp_off, unsigned int tcp_seq)
{
	struct hif_client_tx_queue *queue = &client->tx_q[qno];
	struct tx_queue_desc *desc = queue->base + queue->write_idx;
	struct hif_tso_hdr *tso_hdr;
	u32 tso_hdr_p;

//	printk(KERN_INFO "%s\n",__func__);

	tso_hdr = pfe->hif.tso_hdr_v + pfe->hif.Txtosend;
	tso_hdr_p = (u32)pfe->hif.tso_hdr_p + (pfe->hif.Txtosend * sizeof(struct hif_tso_hdr));

	tso_hdr->ip_off = ip_off;
	tso_hdr->ip_id = ip_id;
	tso_hdr->ip_len = ip_len;
	tso_hdr->tcp_off = tcp_off;
	tso_hdr->tcp_seq = tcp_seq;

	tso_hdr->pkt_hdr.client_id = client->id;
	tso_hdr->pkt_hdr.qNo = qno;
	tso_hdr->pkt_hdr.client_ctrl = client_ctrl;
//	printk(KERN_DEBUG "%s : seq: %x id: %x desc_n: %d desc_addr: %p tx_hdr_v : %p tx_hdr_p: %x, ip_off: %d tcp_off: %d\n",__func__, tso_hdr->tcp_seq, tso_hdr->ip_id, pfe->hif.Txtosend, desc, tso_hdr, tso_hdr_p, tso_hdr->ip_off, tso_hdr->tcp_off );

	desc->data = (void *)0x1; /* bogus non null value to avoid stopping tx done processing */
	desc->ctrl = CL_DESC_OWN | CL_DESC_FLAGS(0);

	__hif_xmit_pkt(&pfe->hif, client->id, qno, (void *)tso_hdr_p, sizeof(struct hif_tso_hdr), HIF_DONT_DMA_MAP | HIF_TSO);

	inc_cl_idx(queue->write_idx);
	queue->tx_pending++;
}
	
static inline void hif_hdr_write(struct hif_hdr *pkt_hdr, unsigned int client_id, unsigned int qno, u32 client_ctrl)
{
	/* Optimize the write since the destinaton may be non-cacheable */
	if (!((unsigned long)pkt_hdr & 0x3)) {
		((u32 *)pkt_hdr)[0] = (client_ctrl << 16) | (qno << 8) | client_id;
	} else {
		((u16 *)pkt_hdr)[0] = (qno << 8) | client_id;
		((u16 *)pkt_hdr)[1] = client_ctrl;
	}
}

/*This function puts the given packet in the specific client queue */
void __hif_lib_xmit_pkt(struct hif_client_s *client, unsigned int qno, void *data, unsigned int len, u32 client_ctrl, unsigned int flags, void *client_data)
{
	struct hif_client_tx_queue *queue = &client->tx_q[qno];
	struct tx_queue_desc *desc = queue->base + queue->write_idx;

	//printk(KERN_INFO "%s\n",__func__);

	/* First buffer */
	if (flags & HIF_FIRST_BUFFER)
	{
		data -= sizeof(struct hif_hdr);
		len += sizeof(struct hif_hdr);

		hif_hdr_write(data, client->id, qno, client_ctrl);
	}

	desc->data = client_data;
	desc->ctrl = CL_DESC_OWN | CL_DESC_FLAGS(flags);

	__hif_xmit_pkt(&pfe->hif, client->id, qno, data, len, flags);

	inc_cl_idx(queue->write_idx);
	queue->tx_pending++;
	queue->jiffies_last_packet = jiffies;
}

/*This function puts the given packet in the specific client queue */
int hif_lib_xmit_pkt(struct hif_client_s *client, unsigned int qno, void *data, unsigned int len, u32 client_ctrl, void *client_data)
{
	struct hif_client_tx_queue *queue = &client->tx_q[qno];
	struct tx_queue_desc *desc = queue->base + queue->write_idx;

	//printk(KERN_INFO "%s\n",__func__);

	if (queue->tx_pending < queue->size) {
		/*Construct pkt header */

		data -= sizeof(struct hif_hdr);
		len += sizeof(struct hif_hdr);

		hif_hdr_write(data, client->id, qno, client_ctrl);

		desc->data = client_data;
		desc->ctrl = CL_DESC_OWN | CL_DESC_FLAGS(HIF_FIRST_BUFFER | HIF_LAST_BUFFER | HIF_DATA_VALID);

		if (hif_xmit_pkt(&pfe->hif, client->id, qno, data, len))
			return 1;

		inc_cl_idx(queue->write_idx);
		queue->tx_pending++;
		queue->jiffies_last_packet = jiffies;

		return 0;
	}

	dbg_print_info("%s Tx client %d qno %d is full\n",__func__, client->id, qno);
	return 1;
}

void *hif_lib_tx_get_next_complete(struct hif_client_s *client, int qno, unsigned int *flags, int count)
{
	struct hif_client_tx_queue *queue = &client->tx_q[qno];
	struct tx_queue_desc *desc = queue->base + queue->read_idx;

	dbg_print_info("%s: qno : %d rd_indx: %d pending:%d\n",__func__, qno, queue->read_idx, queue->tx_pending);

	if (!queue->tx_pending)
		return NULL;

	if (desc->ctrl & CL_DESC_OWN) {
		hif_tx_done_process(&pfe->hif, count);

		//Check again, if packets done in tx queue.
		if (desc->ctrl & CL_DESC_OWN)
			return NULL;
	}

	inc_cl_idx(queue->read_idx);
	queue->tx_pending--;

	*flags = CL_DESC_GET_FLAGS(desc->ctrl);

	return desc->data;
}

//FIXME: TMU queues length mapping needs to be declared in shared PFE/PFE_CTRL header
static void hif_lib_tmu_credit_init(struct pfe *pfe)
{
	int i, q;

	for (i = 0; i < NUM_GEMAC_SUPPORT; i++)
		for (q = 0; q < EMAC_TXQ_CNT; q++) {
			pfe->tmu_credit.tx_credit_max[i][q] = (q == 0) ? DEFAULT_Q0_QDEPTH : DEFAULT_MAX_QDEPTH;
			pfe->tmu_credit.tx_credit[i][q] = pfe->tmu_credit.tx_credit_max[i][q];
		}
}
/** __hif_lib_update_credit
 *
 * @param[in] client	hif client context
 * @param[in] queue	queue number in match with TMU
 */
void __hif_lib_update_credit(struct hif_client_s *client, unsigned int queue)
{
	unsigned int tmu_tx_packets, tmp;

	if (tx_qos) {
		tmu_tx_packets = be32_to_cpu(pe_dmem_read(TMU0_ID + client->id, virt_to_tmu_dmem(&tx_trans[queue]), 4));

		// tx_packets counter overflowed
		if (tmu_tx_packets > pfe->tmu_credit.tx_packets[client->id][queue]) {
			tmp = UINT_MAX - tmu_tx_packets + pfe->tmu_credit.tx_packets[client->id][queue];
			pfe->tmu_credit.tx_credit[client->id][queue] = pfe->tmu_credit.tx_credit_max[client->id][queue] - tmp;
		}
		// TMU tx <= pfe_eth tx, normal case or both OF since last time
		else
			pfe->tmu_credit.tx_credit[client->id][queue] = pfe->tmu_credit.tx_credit_max[client->id][queue] - (pfe->tmu_credit.tx_packets[client->id][queue] - tmu_tx_packets);
	}
}

/** hif_lib_update_credit
 *
 * @param[in] client	hif client context
 * @param[in] queue	queue number in match with TMU
 */
void hif_lib_update_credit(struct hif_client_s *client, unsigned int queue)
{
	spin_lock_bh(&pfe->hif.tx_lock);
	__hif_lib_update_credit(client, queue);
	spin_unlock_bh(&pfe->hif.tx_lock);
}


#ifdef CONFIG_HOTPLUG_CPU
/**  pfe_hif_lib_cpu_notifier
 *
 * @param[in] nfb	cpu notifier control block.
 * @param[in] action	event to notify.
 * @param[in] hcpu 	cpu id.
 */
static int pfe_hif_lib_cpu_notifier(struct notifier_block *nfb, unsigned long action, void *hcpu)
{
	int cpu = (long)hcpu;
	int ii;
	unsigned long flags;

	spin_lock_irqsave(&pfe->hif.lock, flags);
	switch (action & ~CPU_TASKS_FROZEN) {
		case CPU_DOWN_FAILED:
		case CPU_ONLINE:
			printk(KERN_INFO "%s : CPU (%d) is up\n", __func__, cpu);

			for (ii = 0; ii < HIF_CLIENTS_MAX; ii++) {
				if (pfe->hif_client[ii] && (pfe->hif_client[ii]->user_cpu_id == cpu))
					pfe->hif_client[ii]->cpu_id = pfe->hif_client[ii]->user_cpu_id;
			}
			break;

		case CPU_DOWN_PREPARE:
			printk(KERN_INFO "%s : CPU (%d) is down\n", __func__, cpu);

			for (ii = 0; ii < HIF_CLIENTS_MAX; ii++) {
				if (pfe->hif_client[ii] && (pfe->hif_client[ii]->user_cpu_id == cpu))
					pfe->hif_client[ii]->cpu_id = -1;
			}
			break;
		default:
			break;
	}
	spin_unlock_irqrestore(&pfe->hif.lock, flags);

	return NOTIFY_OK;
}
#endif


int pfe_hif_lib_init(struct pfe *pfe)
{
	int rc;

	printk(KERN_INFO "%s\n", __func__);

	if (lro_mode) {
		page_mode = 1;
		pfe_pkt_size = min(PAGE_SIZE, MAX_PFE_PKT_SIZE);
		pfe_pkt_headroom = 0;
	} else {
		page_mode = 0;
		pfe_pkt_size = PFE_PKT_SIZE;
		pfe_pkt_headroom = PFE_PKT_HEADROOM;
	}
	hif_lib_tmu_credit_init(pfe);
	pfe->hif.shm = &ghif_shm;
	rc = pfe_hif_shm_init(pfe->hif.shm);

#ifdef CONFIG_HOTPLUG_CPU
	if (rc)
		goto err_shm_init;

	pfe->hif.cpu_notify.notifier_call = pfe_hif_lib_cpu_notifier;
	pfe->hif.cpu_notify.priority = 0;

	rc = register_cpu_notifier(&pfe->hif.cpu_notify);

	if (rc)
		pfe_hif_shm_clean(pfe->hif.shm);


err_shm_init:
#endif

	return rc;
}


void pfe_hif_lib_exit(struct pfe *pfe)
{
	printk(KERN_INFO "%s\n", __func__);

#ifdef CONFIG_HOTPLUG_CPU
	unregister_cpu_notifier(&pfe->hif.cpu_notify);
#endif
	pfe_hif_shm_clean(pfe->hif.shm);
}