/*
 *  IBM eServer eHCA Infiniband device driver for Linux on POWER
 *
 *  address vector functions
 *
 *  Authors: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
 *           Khadija Souissi <souissik@de.ibm.com>
 *           Reinhard Ernst <rernst@de.ibm.com>
 *           Christoph Raisch <raisch@de.ibm.com>
 *
 *  Copyright (c) 2005 IBM Corporation
 *
 *  All rights reserved.
 *
 *  This source code is distributed under a dual license of GPL v2.0 and OpenIB
 *  BSD.
 *
 * OpenIB BSD License
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials
 * provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/slab.h>

#include "ehca_tools.h"
#include "ehca_iverbs.h"
#include "hcp_if.h"

static struct kmem_cache *av_cache;

int ehca_calc_ipd(struct ehca_shca *shca, int port,
		  enum ib_rate path_rate, u32 *ipd)
{
	int path = ib_rate_to_mult(path_rate);
	int link, ret;
	struct ib_port_attr pa;

	if (path_rate == IB_RATE_PORT_CURRENT) {
		*ipd = 0;
		return 0;
	}

	if (unlikely(path < 0)) {
		ehca_err(&shca->ib_device, "Invalid static rate! path_rate=%x",
			 path_rate);
		return -EINVAL;
	}

	ret = ehca_query_port(&shca->ib_device, port, &pa);
	if (unlikely(ret < 0)) {
		ehca_err(&shca->ib_device, "Failed to query port  ret=%i", ret);
		return ret;
	}

	link = ib_width_enum_to_int(pa.active_width) * pa.active_speed;

	if (path >= link)
		/* no need to throttle if path faster than link */
		*ipd = 0;
	else
		/* IPD = round((link / path) - 1) */
		*ipd = ((link + (path >> 1)) / path) - 1;

	return 0;
}

struct ib_ah *ehca_create_ah(struct ib_pd *pd, struct ib_ah_attr *ah_attr)
{
	int ret;
	struct ehca_av *av;
	struct ehca_shca *shca = container_of(pd->device, struct ehca_shca,
					      ib_device);

	av = kmem_cache_alloc(av_cache, GFP_KERNEL);
	if (!av) {
		ehca_err(pd->device, "Out of memory pd=%p ah_attr=%p",
			 pd, ah_attr);
		return ERR_PTR(-ENOMEM);
	}

	av->av.sl = ah_attr->sl;
	av->av.dlid = ah_attr->dlid;
	av->av.slid_path_bits = ah_attr->src_path_bits;

	if (ehca_static_rate < 0) {
		u32 ipd;
		if (ehca_calc_ipd(shca, ah_attr->port_num,
				  ah_attr->static_rate, &ipd)) {
			ret = -EINVAL;
			goto create_ah_exit1;
		}
		av->av.ipd = ipd;
	} else
		av->av.ipd = ehca_static_rate;

	av->av.lnh = ah_attr->ah_flags;
	av->av.grh.word_0 = EHCA_BMASK_SET(GRH_IPVERSION_MASK, 6);
	av->av.grh.word_0 |= EHCA_BMASK_SET(GRH_TCLASS_MASK,
					    ah_attr->grh.traffic_class);
	av->av.grh.word_0 |= EHCA_BMASK_SET(GRH_FLOWLABEL_MASK,
					    ah_attr->grh.flow_label);
	av->av.grh.word_0 |= EHCA_BMASK_SET(GRH_HOPLIMIT_MASK,
					    ah_attr->grh.hop_limit);
	av->av.grh.word_0 |= EHCA_BMASK_SET(GRH_NEXTHEADER_MASK, 0x1B);
	/* set sgid in grh.word_1 */
	if (ah_attr->ah_flags & IB_AH_GRH) {
		int rc;
		struct ib_port_attr port_attr;
		union ib_gid gid;
		memset(&port_attr, 0, sizeof(port_attr));
		rc = ehca_query_port(pd->device, ah_attr->port_num,
				     &port_attr);
		if (rc) { /* invalid port number */
			ret = -EINVAL;
			ehca_err(pd->device, "Invalid port number "
				 "ehca_query_port() returned %x "
				 "pd=%p ah_attr=%p", rc, pd, ah_attr);
			goto create_ah_exit1;
		}
		memset(&gid, 0, sizeof(gid));
		rc = ehca_query_gid(pd->device,
				    ah_attr->port_num,
				    ah_attr->grh.sgid_index, &gid);
		if (rc) {
			ret = -EINVAL;
			ehca_err(pd->device, "Failed to retrieve sgid "
				 "ehca_query_gid() returned %x "
				 "pd=%p ah_attr=%p", rc, pd, ah_attr);
			goto create_ah_exit1;
		}
		memcpy(&av->av.grh.word_1, &gid, sizeof(gid));
	}
	av->av.pmtu = shca->max_mtu;

	/* dgid comes in grh.word_3 */
	memcpy(&av->av.grh.word_3, &ah_attr->grh.dgid,
	       sizeof(ah_attr->grh.dgid));

	return &av->ib_ah;

create_ah_exit1:
	kmem_cache_free(av_cache, av);

	return ERR_PTR(ret);
}

int ehca_modify_ah(struct ib_ah *ah, struct ib_ah_attr *ah_attr)
{
	struct ehca_av *av;
	struct ehca_ud_av new_ehca_av;
	struct ehca_shca *shca = container_of(ah->pd->device, struct ehca_shca,
					      ib_device);

	memset(&new_ehca_av, 0, sizeof(new_ehca_av));
	new_ehca_av.sl = ah_attr->sl;
	new_ehca_av.dlid = ah_attr->dlid;
	new_ehca_av.slid_path_bits = ah_attr->src_path_bits;
	new_ehca_av.ipd = ah_attr->static_rate;
	new_ehca_av.lnh = EHCA_BMASK_SET(GRH_FLAG_MASK,
					 (ah_attr->ah_flags & IB_AH_GRH) > 0);
	new_ehca_av.grh.word_0 = EHCA_BMASK_SET(GRH_TCLASS_MASK,
						ah_attr->grh.traffic_class);
	new_ehca_av.grh.word_0 |= EHCA_BMASK_SET(GRH_FLOWLABEL_MASK,
						 ah_attr->grh.flow_label);
	new_ehca_av.grh.word_0 |= EHCA_BMASK_SET(GRH_HOPLIMIT_MASK,
						 ah_attr->grh.hop_limit);
	new_ehca_av.grh.word_0 |= EHCA_BMASK_SET(GRH_NEXTHEADER_MASK, 0x1b);

	/* set sgid in grh.word_1 */
	if (ah_attr->ah_flags & IB_AH_GRH) {
		int rc;
		struct ib_port_attr port_attr;
		union ib_gid gid;
		memset(&port_attr, 0, sizeof(port_attr));
		rc = ehca_query_port(ah->device, ah_attr->port_num,
				     &port_attr);
		if (rc) { /* invalid port number */
			ehca_err(ah->device, "Invalid port number "
				 "ehca_query_port() returned %x "
				 "ah=%p ah_attr=%p port_num=%x",
				 rc, ah, ah_attr, ah_attr->port_num);
			return -EINVAL;
		}
		memset(&gid, 0, sizeof(gid));
		rc = ehca_query_gid(ah->device,
				    ah_attr->port_num,
				    ah_attr->grh.sgid_index, &gid);
		if (rc) {
			ehca_err(ah->device, "Failed to retrieve sgid "
				 "ehca_query_gid() returned %x "
				 "ah=%p ah_attr=%p port_num=%x "
				 "sgid_index=%x",
				 rc, ah, ah_attr, ah_attr->port_num,
				 ah_attr->grh.sgid_index);
			return -EINVAL;
		}
		memcpy(&new_ehca_av.grh.word_1, &gid, sizeof(gid));
	}

	new_ehca_av.pmtu = shca->max_mtu;

	memcpy(&new_ehca_av.grh.word_3, &ah_attr->grh.dgid,
	       sizeof(ah_attr->grh.dgid));

	av = container_of(ah, struct ehca_av, ib_ah);
	av->av = new_ehca_av;

	return 0;
}

int ehca_query_ah(struct ib_ah *ah, struct ib_ah_attr *ah_attr)
{
	struct ehca_av *av = container_of(ah, struct ehca_av, ib_ah);

	memcpy(&ah_attr->grh.dgid, &av->av.grh.word_3,
	       sizeof(ah_attr->grh.dgid));
	ah_attr->sl = av->av.sl;

	ah_attr->dlid = av->av.dlid;

	ah_attr->src_path_bits = av->av.slid_path_bits;
	ah_attr->static_rate = av->av.ipd;
	ah_attr->ah_flags = EHCA_BMASK_GET(GRH_FLAG_MASK, av->av.lnh);
	ah_attr->grh.traffic_class = EHCA_BMASK_GET(GRH_TCLASS_MASK,
						    av->av.grh.word_0);
	ah_attr->grh.hop_limit = EHCA_BMASK_GET(GRH_HOPLIMIT_MASK,
						av->av.grh.word_0);
	ah_attr->grh.flow_label = EHCA_BMASK_GET(GRH_FLOWLABEL_MASK,
						 av->av.grh.word_0);

	return 0;
}

int ehca_destroy_ah(struct ib_ah *ah)
{
	kmem_cache_free(av_cache, container_of(ah, struct ehca_av, ib_ah));

	return 0;
}

int ehca_init_av_cache(void)
{
	av_cache = kmem_cache_create("ehca_cache_av",
				   sizeof(struct ehca_av), 0,
				   SLAB_HWCACHE_ALIGN,
				   NULL);
	if (!av_cache)
		return -ENOMEM;
	return 0;
}

void ehca_cleanup_av_cache(void)
{
	if (av_cache)
		kmem_cache_destroy(av_cache);
}