/*
 * Copyright (C) 2016 Cavium, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License
 * as published by the Free Software Foundation.
 */
#include <linux/module.h>
#include "cptpf.h"

static void cpt_send_msg_to_vf(struct cpt_device *cpt, int vf,
			       struct cpt_mbox *mbx)
{
	/* Writing mbox(0) causes interrupt */
	cpt_write_csr64(cpt->reg_base, CPTX_PF_VFX_MBOXX(0, vf, 1),
			mbx->data);
	cpt_write_csr64(cpt->reg_base, CPTX_PF_VFX_MBOXX(0, vf, 0), mbx->msg);
}

/* ACKs VF's mailbox message
 * @vf: VF to which ACK to be sent
 */
static void cpt_mbox_send_ack(struct cpt_device *cpt, int vf,
			      struct cpt_mbox *mbx)
{
	mbx->data = 0ull;
	mbx->msg = CPT_MBOX_MSG_TYPE_ACK;
	cpt_send_msg_to_vf(cpt, vf, mbx);
}

static void cpt_clear_mbox_intr(struct cpt_device *cpt, u32 vf)
{
	/* W1C for the VF */
	cpt_write_csr64(cpt->reg_base, CPTX_PF_MBOX_INTX(0, 0), (1 << vf));
}

/*
 *  Configure QLEN/Chunk sizes for VF
 */
static void cpt_cfg_qlen_for_vf(struct cpt_device *cpt, int vf, u32 size)
{
	union cptx_pf_qx_ctl pf_qx_ctl;

	pf_qx_ctl.u = cpt_read_csr64(cpt->reg_base, CPTX_PF_QX_CTL(0, vf));
	pf_qx_ctl.s.size = size;
	pf_qx_ctl.s.cont_err = true;
	cpt_write_csr64(cpt->reg_base, CPTX_PF_QX_CTL(0, vf), pf_qx_ctl.u);
}

/*
 * Configure VQ priority
 */
static void cpt_cfg_vq_priority(struct cpt_device *cpt, int vf, u32 pri)
{
	union cptx_pf_qx_ctl pf_qx_ctl;

	pf_qx_ctl.u = cpt_read_csr64(cpt->reg_base, CPTX_PF_QX_CTL(0, vf));
	pf_qx_ctl.s.pri = pri;
	cpt_write_csr64(cpt->reg_base, CPTX_PF_QX_CTL(0, vf), pf_qx_ctl.u);
}

static int cpt_bind_vq_to_grp(struct cpt_device *cpt, u8 q, u8 grp)
{
	struct microcode *mcode = cpt->mcode;
	union cptx_pf_qx_ctl pf_qx_ctl;
	struct device *dev = &cpt->pdev->dev;

	if (q >= CPT_MAX_VF_NUM) {
		dev_err(dev, "Queues are more than cores in the group");
		return -EINVAL;
	}
	if (grp >= CPT_MAX_CORE_GROUPS) {
		dev_err(dev, "Request group is more than possible groups");
		return -EINVAL;
	}
	if (grp >= cpt->next_mc_idx) {
		dev_err(dev, "Request group is higher than available functional groups");
		return -EINVAL;
	}
	pf_qx_ctl.u = cpt_read_csr64(cpt->reg_base, CPTX_PF_QX_CTL(0, q));
	pf_qx_ctl.s.grp = mcode[grp].group;
	cpt_write_csr64(cpt->reg_base, CPTX_PF_QX_CTL(0, q), pf_qx_ctl.u);
	dev_dbg(dev, "VF %d TYPE %s", q, (mcode[grp].is_ae ? "AE" : "SE"));

	return mcode[grp].is_ae ? AE_TYPES : SE_TYPES;
}

/* Interrupt handler to handle mailbox messages from VFs */
static void cpt_handle_mbox_intr(struct cpt_device *cpt, int vf)
{
	struct cpt_vf_info *vfx = &cpt->vfinfo[vf];
	struct cpt_mbox mbx = {};
	int vftype;
	struct device *dev = &cpt->pdev->dev;
	/*
	 * MBOX[0] contains msg
	 * MBOX[1] contains data
	 */
	mbx.msg  = cpt_read_csr64(cpt->reg_base, CPTX_PF_VFX_MBOXX(0, vf, 0));
	mbx.data = cpt_read_csr64(cpt->reg_base, CPTX_PF_VFX_MBOXX(0, vf, 1));
	dev_dbg(dev, "%s: Mailbox msg 0x%llx from VF%d", __func__, mbx.msg, vf);
	switch (mbx.msg) {
	case CPT_MSG_VF_UP:
		vfx->state = VF_STATE_UP;
		try_module_get(THIS_MODULE);
		cpt_mbox_send_ack(cpt, vf, &mbx);
		break;
	case CPT_MSG_READY:
		mbx.msg  = CPT_MSG_READY;
		mbx.data = vf;
		cpt_send_msg_to_vf(cpt, vf, &mbx);
		break;
	case CPT_MSG_VF_DOWN:
		/* First msg in VF teardown sequence */
		vfx->state = VF_STATE_DOWN;
		module_put(THIS_MODULE);
		cpt_mbox_send_ack(cpt, vf, &mbx);
		break;
	case CPT_MSG_QLEN:
		vfx->qlen = mbx.data;
		cpt_cfg_qlen_for_vf(cpt, vf, vfx->qlen);
		cpt_mbox_send_ack(cpt, vf, &mbx);
		break;
	case CPT_MSG_QBIND_GRP:
		vftype = cpt_bind_vq_to_grp(cpt, vf, (u8)mbx.data);
		if ((vftype != AE_TYPES) && (vftype != SE_TYPES))
			dev_err(dev, "Queue %d binding to group %llu failed",
				vf, mbx.data);
		else {
			dev_dbg(dev, "Queue %d binding to group %llu successful",
				vf, mbx.data);
			mbx.msg = CPT_MSG_QBIND_GRP;
			mbx.data = vftype;
			cpt_send_msg_to_vf(cpt, vf, &mbx);
		}
		break;
	case CPT_MSG_VQ_PRIORITY:
		vfx->priority = mbx.data;
		cpt_cfg_vq_priority(cpt, vf, vfx->priority);
		cpt_mbox_send_ack(cpt, vf, &mbx);
		break;
	default:
		dev_err(&cpt->pdev->dev, "Invalid msg from VF%d, msg 0x%llx\n",
			vf, mbx.msg);
		break;
	}
}

void cpt_mbox_intr_handler (struct cpt_device *cpt, int mbx)
{
	u64 intr;
	u8  vf;

	intr = cpt_read_csr64(cpt->reg_base, CPTX_PF_MBOX_INTX(0, 0));
	dev_dbg(&cpt->pdev->dev, "PF interrupt Mbox%d 0x%llx\n", mbx, intr);
	for (vf = 0; vf < CPT_MAX_VF_NUM; vf++) {
		if (intr & (1ULL << vf)) {
			dev_dbg(&cpt->pdev->dev, "Intr from VF %d\n", vf);
			cpt_handle_mbox_intr(cpt, vf);
			cpt_clear_mbox_intr(cpt, vf);
		}
	}
}