/* $NetBSD: rtwphyio.c,v 1.19 2016/10/09 14:42:30 christos Exp $ */
/*-
 * Copyright (c) 2004, 2005 David Young.  All rights reserved.
 *
 * Programmed for NetBSD by David Young.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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 David Young ``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 David
 * Young 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.
 */
/*
 * Control input/output with the Philips SA2400 RF front-end and
 * the baseband processor built into the Realtek RTL8180.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rtwphyio.c,v 1.19 2016/10/09 14:42:30 christos Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/device.h>

#include <sys/bus.h>

#include <net/if.h>
#include <net/if_media.h>
#include <net/if_ether.h>

#include <net80211/ieee80211_netbsd.h>
#include <net80211/ieee80211_radiotap.h>
#include <net80211/ieee80211_var.h>

#include <dev/ic/rtwreg.h>
#include <dev/ic/max2820reg.h>
#include <dev/ic/sa2400reg.h>
#include <dev/ic/si4136reg.h>
#include <dev/ic/rtwvar.h>
#include <dev/ic/rtwphyio.h>
#include <dev/ic/rtwphy.h>

static int rtw_macbangbits_timeout = 100;

uint8_t
rtw_bbp_read(struct rtw_regs *regs, u_int addr)
{
        KASSERT((addr & ~__SHIFTOUT_MASK(RTW_BB_ADDR_MASK)) == 0);
        RTW_WRITE(regs, RTW_BB,
            __SHIFTIN(addr, RTW_BB_ADDR_MASK) | RTW_BB_RD_MASK | RTW_BB_WR_MASK);
        delay(10);      /* XXX */
        RTW_WBR(regs, RTW_BB, RTW_BB);
        return __SHIFTOUT(RTW_READ(regs, RTW_BB), RTW_BB_RD_MASK);
}

int
rtw_bbp_write(struct rtw_regs *regs, u_int addr, u_int val)
{
#define BBP_WRITE_ITERS 50
#define BBP_WRITE_DELAY 1
        int i;
        uint32_t wrbbp, rdbbp;

        RTW_DPRINTF(RTW_DEBUG_PHYIO,
            ("%s: bbp[%u] <- %u\n", __func__, addr, val));

        KASSERT((addr & ~__SHIFTOUT_MASK(RTW_BB_ADDR_MASK)) == 0);
        KASSERT((val & ~__SHIFTOUT_MASK(RTW_BB_WR_MASK)) == 0);

        wrbbp = __SHIFTIN(addr, RTW_BB_ADDR_MASK) | RTW_BB_WREN |
            __SHIFTIN(val, RTW_BB_WR_MASK) | RTW_BB_RD_MASK;

        rdbbp = __SHIFTIN(addr, RTW_BB_ADDR_MASK) |
            RTW_BB_WR_MASK | RTW_BB_RD_MASK;

        RTW_DPRINTF(RTW_DEBUG_PHYIO,
            ("%s: rdbbp = %#08x, wrbbp = %#08x\n", __func__, rdbbp, wrbbp));

        for (i = BBP_WRITE_ITERS; --i >= 0; ) {
                RTW_RBW(regs, RTW_BB, RTW_BB);
                RTW_WRITE(regs, RTW_BB, wrbbp);
                RTW_SYNC(regs, RTW_BB, RTW_BB);
                RTW_WRITE(regs, RTW_BB, rdbbp);
                RTW_SYNC(regs, RTW_BB, RTW_BB);
                delay(BBP_WRITE_DELAY); /* 1 microsecond */
                if (__SHIFTOUT(RTW_READ(regs, RTW_BB),
                                    RTW_BB_RD_MASK) == val) {
                        RTW_DPRINTF(RTW_DEBUG_PHYIO,
                            ("%s: finished in %dus\n", __func__,
                            BBP_WRITE_DELAY * (BBP_WRITE_ITERS - i)));
                        return 0;
                }
                delay(BBP_WRITE_DELAY); /* again */
        }
        printf("%s: timeout\n", __func__);
        return -1;
}

/* Help rtw_rf_hostwrite bang bits to RF over 3-wire interface. */
static inline void
rtw_rf_hostbangbits(struct rtw_regs *regs, uint32_t bits, int lo_to_hi,
    u_int nbits)
{
        int i;
        uint32_t mask, reg;

        KASSERT(nbits <= 32);

        RTW_DPRINTF(RTW_DEBUG_PHYIO,
            ("%s: %u bits, %#08x, %s\n", __func__, nbits, bits,
            (lo_to_hi) ? "lo to hi" : "hi to lo"));

        reg = RTW_PHYCFG_HST;
        RTW_WRITE(regs, RTW_PHYCFG, reg);
        RTW_SYNC(regs, RTW_PHYCFG, RTW_PHYCFG);

        if (lo_to_hi)
                mask = 0x1;
        else
                mask = 1 << (nbits - 1);

        for (i = 0; i < nbits; i++) {
                RTW_DPRINTF(RTW_DEBUG_PHYBITIO,
                    ("%s: bits %#08x mask %#08x -> bit %#08x\n",
                    __func__, bits, mask, bits & mask));

                if ((bits & mask) != 0)
                        reg |= RTW_PHYCFG_HST_DATA;
                else
                        reg &= ~RTW_PHYCFG_HST_DATA;

                reg |= RTW_PHYCFG_HST_CLK;
                RTW_WRITE(regs, RTW_PHYCFG, reg);
                RTW_SYNC(regs, RTW_PHYCFG, RTW_PHYCFG);

                DELAY(2);       /* arbitrary delay */

                reg &= ~RTW_PHYCFG_HST_CLK;
                RTW_WRITE(regs, RTW_PHYCFG, reg);
                RTW_SYNC(regs, RTW_PHYCFG, RTW_PHYCFG);

                if (lo_to_hi)
                        mask <<= 1;
                else
                        mask >>= 1;
        }

        reg |= RTW_PHYCFG_HST_EN;
        KASSERT((reg & RTW_PHYCFG_HST_CLK) == 0);
        RTW_WRITE(regs, RTW_PHYCFG, reg);
        RTW_SYNC(regs, RTW_PHYCFG, RTW_PHYCFG);
}

/* Help rtw_rf_macwrite: tell MAC to bang bits to RF over the 3-wire
 * interface.
 */
static inline int
rtw_rf_macbangbits(struct rtw_regs *regs, uint32_t reg)
{
        int i;

        RTW_DPRINTF(RTW_DEBUG_PHY, ("%s: %#08x\n", __func__, reg));

        RTW_WRITE(regs, RTW_PHYCFG, RTW_PHYCFG_MAC_POLL | reg);

        RTW_WBR(regs, RTW_PHYCFG, RTW_PHYCFG);

        for (i = rtw_macbangbits_timeout; --i >= 0; delay(1)) {
                if ((RTW_READ(regs, RTW_PHYCFG) & RTW_PHYCFG_MAC_POLL) == 0) {
                        RTW_DPRINTF(RTW_DEBUG_PHY,
                            ("%s: finished in %dus\n", __func__,
                            rtw_macbangbits_timeout - i));
                        return 0;
                }
                RTW_RBR(regs, RTW_PHYCFG, RTW_PHYCFG);  /* XXX paranoia? */
        }

        printf("%s: RTW_PHYCFG_MAC_POLL still set.\n", __func__);
        return -1;
}

static uint32_t
rtw_grf5101_host_crypt(u_int addr, uint32_t val)
{
        /* TBD */
        return 0;
}

static uint32_t
rtw_grf5101_mac_crypt(u_int addr, uint32_t val)
{
        uint32_t data_and_addr;
#define EXTRACT_NIBBLE(d, which) (((d) >> (4 * (which))) & 0xf)
        static uint8_t caesar[16] = {0x0, 0x8, 0x4, 0xc,
                                      0x2, 0xa, 0x6, 0xe,
                                      0x1, 0x9, 0x5, 0xd,
                                      0x3, 0xb, 0x7, 0xf};

        data_and_addr =  caesar[EXTRACT_NIBBLE(val, 2)] |
                        (caesar[EXTRACT_NIBBLE(val, 1)] <<  4) |
                        (caesar[EXTRACT_NIBBLE(val, 0)] <<  8) |
                        (caesar[(addr >> 1) & 0xf]      << 12) |
                        ((addr & 0x1)                   << 16) |
                        (caesar[EXTRACT_NIBBLE(val, 3)] << 24);
        return __SHIFTIN(data_and_addr,
            RTW_PHYCFG_MAC_PHILIPS_ADDR_MASK|RTW_PHYCFG_MAC_PHILIPS_DATA_MASK);
#undef EXTRACT_NIBBLE
}

#ifdef RTW_DEBUG
static inline const char *
rtw_rfchipid_string(enum rtw_rfchipid rfchipid)
{
        switch (rfchipid) {
        case RTW_RFCHIPID_MAXIM:
                return "Maxim";
        case RTW_RFCHIPID_PHILIPS:
                return "Philips";
        case RTW_RFCHIPID_GCT:
                return "GCT";
        case RTW_RFCHIPID_RFMD:
                return "RFMD";
        case RTW_RFCHIPID_INTERSIL:
                return "Intersil";
        default:
                return "unknown";
        }
}
#endif

/* Bang bits over the 3-wire interface. */
int
rtw_rf_hostwrite(struct rtw_regs *regs, enum rtw_rfchipid rfchipid,
    u_int addr, uint32_t val)
{
        u_int nbits;
        int lo_to_hi;
        uint32_t bits;

        RTW_DPRINTF(RTW_DEBUG_PHYIO, ("%s: %s[%u] <- %#08x\n", __func__,
            rtw_rfchipid_string(rfchipid), addr, val));

        switch (rfchipid) {
        case RTW_RFCHIPID_MAXIM:
                nbits = 16;
                lo_to_hi = 0;
                bits = __SHIFTIN(val, MAX2820_TWI_DATA_MASK) |
                       __SHIFTIN(addr, MAX2820_TWI_ADDR_MASK);
                break;
        case RTW_RFCHIPID_PHILIPS:
                KASSERT((addr & ~__SHIFTOUT_MASK(SA2400_TWI_ADDR_MASK)) == 0);
                KASSERT((val & ~__SHIFTOUT_MASK(SA2400_TWI_DATA_MASK)) == 0);
                bits = __SHIFTIN(val, SA2400_TWI_DATA_MASK) |
                       __SHIFTIN(addr, SA2400_TWI_ADDR_MASK) | SA2400_TWI_WREN;
                nbits = 32;
                lo_to_hi = 1;
                break;
        case RTW_RFCHIPID_GCT:
                KASSERT((addr & ~__SHIFTOUT_MASK(SI4126_TWI_ADDR_MASK)) == 0);
                KASSERT((val & ~__SHIFTOUT_MASK(SI4126_TWI_DATA_MASK)) == 0);
                bits = rtw_grf5101_host_crypt(addr, val);
                nbits = 21;
                lo_to_hi = 1;
                break;
        case RTW_RFCHIPID_RFMD:
                KASSERT((addr & ~__SHIFTOUT_MASK(SI4126_TWI_ADDR_MASK)) == 0);
                KASSERT((val & ~__SHIFTOUT_MASK(SI4126_TWI_DATA_MASK)) == 0);
                bits = __SHIFTIN(val, SI4126_TWI_DATA_MASK) |
                       __SHIFTIN(addr, SI4126_TWI_ADDR_MASK);
                nbits = 22;
                lo_to_hi = 0;
                break;
        case RTW_RFCHIPID_INTERSIL:
        default:
                printf("%s: unknown rfchipid %d\n", __func__, rfchipid);
                return -1;
        }

        rtw_rf_hostbangbits(regs, bits, lo_to_hi, nbits);

        return 0;
}

static uint32_t
rtw_maxim_swizzle(u_int addr, uint32_t val)
{
        uint32_t hidata, lodata;

        KASSERT((val & ~(RTW_MAXIM_LODATA_MASK|RTW_MAXIM_HIDATA_MASK)) == 0);
        lodata = __SHIFTOUT(val, RTW_MAXIM_LODATA_MASK);
        hidata = __SHIFTOUT(val, RTW_MAXIM_HIDATA_MASK);
        return __SHIFTIN(lodata, RTW_PHYCFG_MAC_MAXIM_LODATA_MASK) |
            __SHIFTIN(hidata, RTW_PHYCFG_MAC_MAXIM_HIDATA_MASK) |
            __SHIFTIN(addr, RTW_PHYCFG_MAC_MAXIM_ADDR_MASK);
}

/* Tell the MAC what to bang over the 3-wire interface. */
int
rtw_rf_macwrite(struct rtw_regs *regs, enum rtw_rfchipid rfchipid,
    u_int addr, uint32_t val)
{
        uint32_t reg;

        RTW_DPRINTF(RTW_DEBUG_PHYIO, ("%s: %s[%u] <- %#08x\n", __func__,
            rtw_rfchipid_string(rfchipid), addr, val));

        switch (rfchipid) {
        case RTW_RFCHIPID_GCT:
                reg = rtw_grf5101_mac_crypt(addr, val);
                break;
        case RTW_RFCHIPID_MAXIM:
                reg = rtw_maxim_swizzle(addr, val);
                break;
        default:                /* XXX */
        case RTW_RFCHIPID_PHILIPS:
                KASSERT(
                    (addr & ~__SHIFTOUT_MASK(RTW_PHYCFG_MAC_PHILIPS_ADDR_MASK)) == 0);
                KASSERT(
                    (val & ~__SHIFTOUT_MASK(RTW_PHYCFG_MAC_PHILIPS_DATA_MASK)) == 0);

                reg = __SHIFTIN(addr, RTW_PHYCFG_MAC_PHILIPS_ADDR_MASK) |
                      __SHIFTIN(val, RTW_PHYCFG_MAC_PHILIPS_DATA_MASK);
        }

        switch (rfchipid) {
        case RTW_RFCHIPID_GCT:
        case RTW_RFCHIPID_MAXIM:
        case RTW_RFCHIPID_RFMD:
                reg |= RTW_PHYCFG_MAC_RFTYPE_RFMD;
                break;
        case RTW_RFCHIPID_INTERSIL:
                reg |= RTW_PHYCFG_MAC_RFTYPE_INTERSIL;
                break;
        case RTW_RFCHIPID_PHILIPS:
                reg |= RTW_PHYCFG_MAC_RFTYPE_PHILIPS;
                break;
        default:
                printf("%s: unknown rfchipid %d\n", __func__, rfchipid);
                return -1;
        }

        return rtw_rf_macbangbits(regs, reg);
}