// SPDX-License-Identifier: GPL-2.0+
/*
 * bdc_cmd.c - BRCM BDC USB3.0 device controller
 *
 * Copyright (C) 2014 Broadcom Corporation
 *
 * Author: Ashwini Pahuja
 */
#include <linux/scatterlist.h>
#include <linux/slab.h>

#include "bdc.h"
#include "bdc_cmd.h"
#include "bdc_dbg.h"

/* Issues a cmd to cmd processor and waits for cmd completion */
static int bdc_issue_cmd(struct bdc *bdc, u32 cmd_sc, u32 param0,
                                                        u32 param1, u32 param2)
{
        u32 timeout = BDC_CMD_TIMEOUT;
        u32 cmd_status;
        u32 temp;

        bdc_writel(bdc->regs, BDC_CMDPAR0, param0);
        bdc_writel(bdc->regs, BDC_CMDPAR1, param1);
        bdc_writel(bdc->regs, BDC_CMDPAR2, param2);

        /* Issue the cmd */
        /* Make sure the cmd params are written before asking HW to exec cmd */
        wmb();
        bdc_writel(bdc->regs, BDC_CMDSC, cmd_sc | BDC_CMD_CWS | BDC_CMD_SRD);
        do {
                temp = bdc_readl(bdc->regs, BDC_CMDSC);
                dev_dbg_ratelimited(bdc->dev, "cmdsc=%x", temp);
                cmd_status =  BDC_CMD_CST(temp);
                if (cmd_status != BDC_CMDS_BUSY)  {
                        dev_dbg(bdc->dev,
                                "command completed cmd_sts:%x\n", cmd_status);
                        return cmd_status;
                }
                udelay(1);
        } while (timeout--);

        dev_err(bdc->dev,
                "command operation timedout cmd_status=%d\n", cmd_status);

        return cmd_status;
}

/* Submits cmd and analyze the return value of bdc_issue_cmd */
static int bdc_submit_cmd(struct bdc *bdc, u32 cmd_sc,
                                        u32 param0, u32 param1, u32 param2)
{
        u32 temp, cmd_status;
        int ret;

        temp = bdc_readl(bdc->regs, BDC_CMDSC);
        dev_dbg(bdc->dev,
                "%s:CMDSC:%08x cmdsc:%08x param0=%08x param1=%08x param2=%08x\n",
                 __func__, temp, cmd_sc, param0, param1, param2);

        cmd_status = BDC_CMD_CST(temp);
        if (cmd_status  ==  BDC_CMDS_BUSY) {
                dev_err(bdc->dev, "command processor busy: %x\n", cmd_status);
                return -EBUSY;
        }
        ret = bdc_issue_cmd(bdc, cmd_sc, param0, param1, param2);
        switch (ret) {
        case BDC_CMDS_SUCC:
                dev_dbg(bdc->dev, "command completed successfully\n");
                ret = 0;
                break;

        case BDC_CMDS_PARA:
                dev_err(bdc->dev, "command parameter error\n");
                ret = -EINVAL;
                break;

        case BDC_CMDS_STAT:
                dev_err(bdc->dev, "Invalid device/ep state\n");
                ret = -EINVAL;
                break;

        case BDC_CMDS_FAIL:
                dev_err(bdc->dev, "Command failed?\n");
                ret = -EAGAIN;
                break;

        case BDC_CMDS_INTL:
                dev_err(bdc->dev, "BDC Internal error\n");
                ret = -ECONNRESET;
                break;

        case BDC_CMDS_BUSY:
                dev_err(bdc->dev,
                        "command timedout waited for %dusec\n",
                        BDC_CMD_TIMEOUT);
                ret = -ECONNRESET;
                break;
        default:
                dev_dbg(bdc->dev, "Unknown command completion code:%x\n", ret);
        }

        return ret;
}

/* Deconfigure the endpoint from HW */
int bdc_dconfig_ep(struct bdc *bdc, struct bdc_ep *ep)
{
        u32 cmd_sc;

        cmd_sc = BDC_SUB_CMD_DRP_EP|BDC_CMD_EPN(ep->ep_num)|BDC_CMD_EPC;
        dev_dbg(bdc->dev, "%s ep->ep_num =%d cmd_sc=%x\n", __func__,
                                                        ep->ep_num, cmd_sc);

        return bdc_submit_cmd(bdc, cmd_sc, 0, 0, 0);
}

/* Reinitalize the bdlist after config ep command */
static void ep_bd_list_reinit(struct bdc_ep *ep)
{
        struct bdc *bdc = ep->bdc;
        struct bdc_bd *bd;

        ep->bd_list.eqp_bdi = 0;
        ep->bd_list.hwd_bdi = 0;
        bd = ep->bd_list.bd_table_array[0]->start_bd;
        dev_dbg(bdc->dev, "%s ep:%p bd:%p\n", __func__, ep, bd);
        memset(bd, 0, sizeof(struct bdc_bd));
        bd->offset[3] |= cpu_to_le32(BD_SBF);
}

/* Configure an endpoint */
int bdc_config_ep(struct bdc *bdc, struct bdc_ep *ep)
{
        const struct usb_ss_ep_comp_descriptor *comp_desc;
        const struct usb_endpoint_descriptor    *desc;
        u32 param0, param1, param2, cmd_sc;
        u32 mps, mbs, mul, si;
        int ret;

        desc = ep->desc;
        comp_desc = ep->comp_desc;
        cmd_sc = mul = mbs = param2 = 0;
        param0 = lower_32_bits(ep->bd_list.bd_table_array[0]->dma);
        param1 = upper_32_bits(ep->bd_list.bd_table_array[0]->dma);
        cpu_to_le32s(&param0);
        cpu_to_le32s(&param1);

        dev_dbg(bdc->dev, "%s: param0=%08x param1=%08x",
                                                __func__, param0, param1);
        si = desc->bInterval;
        si = clamp_val(si, 1, 16) - 1;

        mps = usb_endpoint_maxp(desc);
        param2 |= mps << MP_SHIFT;
        param2 |= usb_endpoint_type(desc) << EPT_SHIFT;

        switch (bdc->gadget.speed) {
        case USB_SPEED_SUPER:
                if (usb_endpoint_xfer_int(desc) ||
                                        usb_endpoint_xfer_isoc(desc)) {
                        param2 |= si;
                        if (usb_endpoint_xfer_isoc(desc) && comp_desc)
                                mul = comp_desc->bmAttributes;

                }
                param2 |= mul << EPM_SHIFT;
                if (comp_desc)
                        mbs = comp_desc->bMaxBurst;
                param2 |= mbs << MB_SHIFT;
                break;

        case USB_SPEED_HIGH:
                if (usb_endpoint_xfer_isoc(desc) ||
                                        usb_endpoint_xfer_int(desc)) {
                        param2 |= si;

                        mbs = usb_endpoint_maxp_mult(desc);
                        param2 |= mbs << MB_SHIFT;
                }
                break;

        case USB_SPEED_FULL:
        case USB_SPEED_LOW:
                /* the hardware accepts SI in 125usec range */
                if (usb_endpoint_xfer_isoc(desc))
                        si += 3;

                /*
                 * FS Int endpoints can have si of 1-255ms but the controller
                 * accepts 2^bInterval*125usec, so convert ms to nearest power
                 * of 2
                 */
                if (usb_endpoint_xfer_int(desc))
                        si = fls(desc->bInterval * 8) - 1;

                param2 |= si;
                break;
        default:
                dev_err(bdc->dev, "UNKNOWN speed ERR\n");
                return -EINVAL;
        }

        cmd_sc |= BDC_CMD_EPC|BDC_CMD_EPN(ep->ep_num)|BDC_SUB_CMD_ADD_EP;

        dev_dbg(bdc->dev, "cmd_sc=%x param2=%08x\n", cmd_sc, param2);
        ret = bdc_submit_cmd(bdc, cmd_sc, param0, param1, param2);
        if (ret) {
                dev_err(bdc->dev, "command failed :%x\n", ret);
                return ret;
        }
        ep_bd_list_reinit(ep);

        return ret;
}

/*
 * Change the HW deq pointer, if this command is successful, HW will start
 * fetching the next bd from address dma_addr.
 */
int bdc_ep_bla(struct bdc *bdc, struct bdc_ep *ep, dma_addr_t dma_addr)
{
        u32 param0, param1;
        u32 cmd_sc = 0;

        dev_dbg(bdc->dev, "%s: add=%08llx\n", __func__,
                                (unsigned long long)(dma_addr));
        param0 = lower_32_bits(dma_addr);
        param1 = upper_32_bits(dma_addr);
        cpu_to_le32s(&param0);
        cpu_to_le32s(&param1);

        cmd_sc |= BDC_CMD_EPN(ep->ep_num)|BDC_CMD_BLA;
        dev_dbg(bdc->dev, "cmd_sc=%x\n", cmd_sc);

        return bdc_submit_cmd(bdc, cmd_sc, param0, param1, 0);
}

/* Set the address sent bu Host in SET_ADD request */
int bdc_address_device(struct bdc *bdc, u32 add)
{
        u32 cmd_sc = 0;
        u32 param2;

        dev_dbg(bdc->dev, "%s: add=%d\n", __func__, add);
        cmd_sc |=  BDC_SUB_CMD_ADD|BDC_CMD_DVC;
        param2 = add & 0x7f;

        return bdc_submit_cmd(bdc, cmd_sc, 0, 0, param2);
}

/* Send a Function Wake notification packet using FH command */
int bdc_function_wake_fh(struct bdc *bdc, u8 intf)
{
        u32 param0, param1;
        u32 cmd_sc = 0;

        param0 = param1 = 0;
        dev_dbg(bdc->dev, "%s intf=%d\n", __func__, intf);
        cmd_sc  |=  BDC_CMD_FH;
        param0 |= TRA_PACKET;
        param0 |= (bdc->dev_addr << 25);
        param1 |= DEV_NOTF_TYPE;
        param1 |= (FWK_SUBTYPE<<4);
        dev_dbg(bdc->dev, "param0=%08x param1=%08x\n", param0, param1);

        return bdc_submit_cmd(bdc, cmd_sc, param0, param1, 0);
}

/* Send a Function Wake notification packet using DNC command */
int bdc_function_wake(struct bdc *bdc, u8 intf)
{
        u32 cmd_sc = 0;
        u32 param2 = 0;

        dev_dbg(bdc->dev, "%s intf=%d", __func__, intf);
        param2 |= intf;
        cmd_sc |= BDC_SUB_CMD_FWK|BDC_CMD_DNC;

        return bdc_submit_cmd(bdc, cmd_sc, 0, 0, param2);
}

/* Stall the endpoint */
int bdc_ep_set_stall(struct bdc *bdc, int epnum)
{
        u32 cmd_sc = 0;

        dev_dbg(bdc->dev, "%s epnum=%d\n", __func__, epnum);
        /* issue a stall endpoint command */
        cmd_sc |=  BDC_SUB_CMD_EP_STL | BDC_CMD_EPN(epnum) | BDC_CMD_EPO;

        return bdc_submit_cmd(bdc, cmd_sc, 0, 0, 0);
}

/* resets the endpoint, called when host sends CLEAR_FEATURE(HALT) */
int bdc_ep_clear_stall(struct bdc *bdc, int epnum)
{
        struct bdc_ep *ep;
        u32 cmd_sc = 0;
        int ret;

        dev_dbg(bdc->dev, "%s: epnum=%d\n", __func__, epnum);
        ep = bdc->bdc_ep_array[epnum];
        /*
         * If we are not in stalled then stall Endpoint and issue clear stall,
         * his will reset the seq number for non EP0.
         */
        if (epnum != 1) {
                /* if the endpoint it not stalled */
                if (!(ep->flags & BDC_EP_STALL)) {
                        ret = bdc_ep_set_stall(bdc, epnum);
                        if (ret)
                                return ret;
                }
        }
        /* Preserve the seq number for ep0 only */
        if (epnum != 1)
                cmd_sc |= BDC_CMD_EPO_RST_SN;

        /* issue a reset endpoint command */
        cmd_sc |=  BDC_SUB_CMD_EP_RST | BDC_CMD_EPN(epnum) | BDC_CMD_EPO;

        ret = bdc_submit_cmd(bdc, cmd_sc, 0, 0, 0);
        if (ret) {
                dev_err(bdc->dev, "command failed:%x\n", ret);
                return ret;
        }
        bdc_notify_xfr(bdc, epnum);

        return ret;
}

/* Stop the endpoint, called when software wants to dequeue some request */
int bdc_stop_ep(struct bdc *bdc, int epnum)
{
        struct bdc_ep *ep;
        u32 cmd_sc = 0;
        int ret;

        ep = bdc->bdc_ep_array[epnum];
        dev_dbg(bdc->dev, "%s: ep:%s ep->flags:%08x\n", __func__,
                                                ep->name, ep->flags);
        /* Endpoint has to be in running state to execute stop ep command */
        if (!(ep->flags & BDC_EP_ENABLED)) {
                dev_err(bdc->dev, "stop endpoint called for disabled ep\n");
                return   -EINVAL;
        }
        if ((ep->flags & BDC_EP_STALL) || (ep->flags & BDC_EP_STOP))
                return 0;

        /* issue a stop endpoint command */
        cmd_sc |= BDC_CMD_EP0_XSD | BDC_SUB_CMD_EP_STP
                                | BDC_CMD_EPN(epnum) | BDC_CMD_EPO;

        ret = bdc_submit_cmd(bdc, cmd_sc, 0, 0, 0);
        if (ret) {
                dev_err(bdc->dev,
                        "stop endpoint command didn't complete:%d ep:%s\n",
                        ret, ep->name);
                return ret;
        }
        ep->flags |= BDC_EP_STOP;
        bdc_dump_epsts(bdc);

        return ret;
}