// SPDX-License-Identifier: GPL-2.0-only
/*******************************************************************************
  Copyright (C) 2007-2009  STMicroelectronics Ltd


  Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
*******************************************************************************/

#include <linux/io.h>
#include <linux/iopoll.h>
#include "common.h"
#include "dwmac_dma.h"
#include "stmmac.h"

#define GMAC_HI_REG_AE          0x80000000

int dwmac_dma_reset(void __iomem *ioaddr)
{
        u32 value = readl(ioaddr + DMA_BUS_MODE);

        /* DMA SW reset */
        value |= DMA_BUS_MODE_SFT_RESET;
        writel(value, ioaddr + DMA_BUS_MODE);

        return readl_poll_timeout(ioaddr + DMA_BUS_MODE, value,
                                 !(value & DMA_BUS_MODE_SFT_RESET),
                                 10000, 200000);
}

/* CSR1 enables the transmit DMA to check for new descriptor */
void dwmac_enable_dma_transmission(void __iomem *ioaddr, u32 chan)
{
        writel(1, ioaddr + DMA_CHAN_XMT_POLL_DEMAND(chan));
}

void dwmac_enable_dma_reception(void __iomem *ioaddr, u32 chan)
{
        writel(1, ioaddr + DMA_CHAN_RCV_POLL_DEMAND(chan));
}

void dwmac_enable_dma_irq(struct stmmac_priv *priv, void __iomem *ioaddr,
                          u32 chan, bool rx, bool tx)
{
        u32 value = readl(ioaddr + DMA_CHAN_INTR_ENA(chan));

        if (rx)
                value |= DMA_INTR_DEFAULT_RX;
        if (tx)
                value |= DMA_INTR_DEFAULT_TX;

        writel(value, ioaddr + DMA_CHAN_INTR_ENA(chan));
}

void dwmac_disable_dma_irq(struct stmmac_priv *priv, void __iomem *ioaddr,
                           u32 chan, bool rx, bool tx)
{
        u32 value = readl(ioaddr + DMA_CHAN_INTR_ENA(chan));

        if (rx)
                value &= ~DMA_INTR_DEFAULT_RX;
        if (tx)
                value &= ~DMA_INTR_DEFAULT_TX;

        writel(value, ioaddr + DMA_CHAN_INTR_ENA(chan));
}

void dwmac_dma_start_tx(struct stmmac_priv *priv, void __iomem *ioaddr,
                        u32 chan)
{
        u32 value = readl(ioaddr + DMA_CHAN_CONTROL(chan));
        value |= DMA_CONTROL_ST;
        writel(value, ioaddr + DMA_CHAN_CONTROL(chan));
}

void dwmac_dma_stop_tx(struct stmmac_priv *priv, void __iomem *ioaddr, u32 chan)
{
        u32 value = readl(ioaddr + DMA_CHAN_CONTROL(chan));
        value &= ~DMA_CONTROL_ST;
        writel(value, ioaddr + DMA_CHAN_CONTROL(chan));
}

void dwmac_dma_start_rx(struct stmmac_priv *priv, void __iomem *ioaddr,
                        u32 chan)
{
        u32 value = readl(ioaddr + DMA_CHAN_CONTROL(chan));
        value |= DMA_CONTROL_SR;
        writel(value, ioaddr + DMA_CHAN_CONTROL(chan));
}

void dwmac_dma_stop_rx(struct stmmac_priv *priv, void __iomem *ioaddr, u32 chan)
{
        u32 value = readl(ioaddr + DMA_CHAN_CONTROL(chan));
        value &= ~DMA_CONTROL_SR;
        writel(value, ioaddr + DMA_CHAN_CONTROL(chan));
}

#ifdef DWMAC_DMA_DEBUG
static void show_tx_process_state(unsigned int status)
{
        switch (FIELD_GET(DMA_STATUS_TS_MASK, status)) {
        case 0:
                pr_debug("- TX (Stopped): Reset or Stop command\n");
                break;
        case 1:
                pr_debug("- TX (Running): Fetching the Tx desc\n");
                break;
        case 2:
                pr_debug("- TX (Running): Waiting for end of tx\n");
                break;
        case 3:
                pr_debug("- TX (Running): Reading the data "
                       "and queuing the data into the Tx buf\n");
                break;
        case 6:
                pr_debug("- TX (Suspended): Tx Buff Underflow "
                       "or an unavailable Transmit descriptor\n");
                break;
        case 7:
                pr_debug("- TX (Running): Closing Tx descriptor\n");
                break;
        default:
                break;
        }
}

static void show_rx_process_state(unsigned int status)
{
        switch (FIELD_GET(DMA_STATUS_RS_MASK, status)) {
        case 0:
                pr_debug("- RX (Stopped): Reset or Stop command\n");
                break;
        case 1:
                pr_debug("- RX (Running): Fetching the Rx desc\n");
                break;
        case 2:
                pr_debug("- RX (Running): Checking for end of pkt\n");
                break;
        case 3:
                pr_debug("- RX (Running): Waiting for Rx pkt\n");
                break;
        case 4:
                pr_debug("- RX (Suspended): Unavailable Rx buf\n");
                break;
        case 5:
                pr_debug("- RX (Running): Closing Rx descriptor\n");
                break;
        case 6:
                pr_debug("- RX(Running): Flushing the current frame"
                       " from the Rx buf\n");
                break;
        case 7:
                pr_debug("- RX (Running): Queuing the Rx frame"
                       " from the Rx buf into memory\n");
                break;
        default:
                break;
        }
}
#endif

int dwmac_dma_interrupt(struct stmmac_priv *priv, void __iomem *ioaddr,
                        struct stmmac_extra_stats *x, u32 chan, u32 dir)
{
        struct stmmac_pcpu_stats *stats = this_cpu_ptr(priv->xstats.pcpu_stats);
        int ret = 0;
        /* read the status register (CSR5) */
        u32 intr_status = readl(ioaddr + DMA_CHAN_STATUS(chan));

#ifdef DWMAC_DMA_DEBUG
        /* Enable it to monitor DMA rx/tx status in case of critical problems */
        pr_debug("%s: [CSR5: 0x%08x]\n", __func__, intr_status);
        show_tx_process_state(intr_status);
        show_rx_process_state(intr_status);
#endif

        if (dir == DMA_DIR_RX)
                intr_status &= DMA_STATUS_MSK_RX;
        else if (dir == DMA_DIR_TX)
                intr_status &= DMA_STATUS_MSK_TX;

        /* ABNORMAL interrupts */
        if (unlikely(intr_status & DMA_STATUS_AIS)) {
                if (unlikely(intr_status & DMA_STATUS_UNF)) {
                        ret = tx_hard_error_bump_tc;
                        x->tx_undeflow_irq++;
                }
                if (unlikely(intr_status & DMA_STATUS_TJT))
                        x->tx_jabber_irq++;

                if (unlikely(intr_status & DMA_STATUS_OVF))
                        x->rx_overflow_irq++;

                if (unlikely(intr_status & DMA_STATUS_RU))
                        x->rx_buf_unav_irq++;
                if (unlikely(intr_status & DMA_STATUS_RPS))
                        x->rx_process_stopped_irq++;
                if (unlikely(intr_status & DMA_STATUS_RWT))
                        x->rx_watchdog_irq++;
                if (unlikely(intr_status & DMA_STATUS_ETI))
                        x->tx_early_irq++;
                if (unlikely(intr_status & DMA_STATUS_TPS)) {
                        x->tx_process_stopped_irq++;
                        ret = tx_hard_error;
                }
                if (unlikely(intr_status & DMA_STATUS_FBI)) {
                        x->fatal_bus_error_irq++;
                        ret = tx_hard_error;
                }
        }
        /* TX/RX NORMAL interrupts */
        if (likely(intr_status & DMA_STATUS_NIS)) {
                if (likely(intr_status & DMA_STATUS_RI)) {
                        u32 value = readl(ioaddr + DMA_INTR_ENA);
                        /* to schedule NAPI on real RIE event. */
                        if (likely(value & DMA_INTR_ENA_RIE)) {
                                u64_stats_update_begin(&stats->syncp);
                                u64_stats_inc(&stats->rx_normal_irq_n[chan]);
                                u64_stats_update_end(&stats->syncp);
                                ret |= handle_rx;
                        }
                }
                if (likely(intr_status & DMA_STATUS_TI)) {
                        u64_stats_update_begin(&stats->syncp);
                        u64_stats_inc(&stats->tx_normal_irq_n[chan]);
                        u64_stats_update_end(&stats->syncp);
                        ret |= handle_tx;
                }
                if (unlikely(intr_status & DMA_STATUS_ERI))
                        x->rx_early_irq++;
        }
        /* Optional hardware blocks, interrupts should be disabled */
        if (unlikely(intr_status &
                     (DMA_STATUS_GPI | DMA_STATUS_GMI | DMA_STATUS_GLI)))
                pr_warn("%s: unexpected status %08x\n", __func__, intr_status);

        /* Clear the interrupt by writing a logic 1 to the CSR5[15-0] */
        writel((intr_status & 0x1ffff), ioaddr + DMA_STATUS);

        return ret;
}

void dwmac_dma_flush_tx_fifo(void __iomem *ioaddr)
{
        u32 csr6 = readl(ioaddr + DMA_CONTROL);
        writel((csr6 | DMA_CONTROL_FTF), ioaddr + DMA_CONTROL);

        do {} while ((readl(ioaddr + DMA_CONTROL) & DMA_CONTROL_FTF));
}

void stmmac_set_mac_addr(void __iomem *ioaddr, const u8 addr[6],
                         unsigned int high, unsigned int low)
{
        u32 data;

        data = (addr[5] << 8) | addr[4];
        /* For MAC Addr registers we have to set the Address Enable (AE)
         * bit that has no effect on the High Reg 0 where the bit 31 (MO)
         * is RO.
         */
        writel(data | GMAC_HI_REG_AE, ioaddr + high);
        data = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0];
        writel(data, ioaddr + low);
}
EXPORT_SYMBOL_GPL(stmmac_set_mac_addr);

/* Enable disable MAC RX/TX */
void stmmac_set_mac(void __iomem *ioaddr, bool enable)
{
        u32 old_val, value;

        old_val = readl(ioaddr + MAC_CTRL_REG);
        value = old_val;

        if (enable)
                value |= MAC_ENABLE_RX | MAC_ENABLE_TX;
        else
                value &= ~(MAC_ENABLE_TX | MAC_ENABLE_RX);

        if (value != old_val)
                writel(value, ioaddr + MAC_CTRL_REG);
}

void stmmac_get_mac_addr(void __iomem *ioaddr, unsigned char *addr,
                         unsigned int high, unsigned int low)
{
        unsigned int hi_addr, lo_addr;

        /* Read the MAC address from the hardware */
        hi_addr = readl(ioaddr + high);
        lo_addr = readl(ioaddr + low);

        /* Extract the MAC address from the high and low words */
        addr[0] = lo_addr & 0xff;
        addr[1] = (lo_addr >> 8) & 0xff;
        addr[2] = (lo_addr >> 16) & 0xff;
        addr[3] = (lo_addr >> 24) & 0xff;
        addr[4] = hi_addr & 0xff;
        addr[5] = (hi_addr >> 8) & 0xff;
}
EXPORT_SYMBOL_GPL(stmmac_get_mac_addr);