// SPDX-License-Identifier: GPL-2.0-only
/*******************************************************************************
  This is the driver for the GMAC on-chip Ethernet controller for ST SoCs.
  DWC Ether MAC 10/100/1000 Universal version 3.41a  has been used for
  developing this code.

  This contains the functions to handle the dma.

  Copyright (C) 2007-2009  STMicroelectronics Ltd


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

#include <linux/io.h>
#include "dwmac1000.h"
#include "dwmac_dma.h"

static void dwmac1000_dma_axi(void __iomem *ioaddr, struct stmmac_axi *axi)
{
        u32 value = readl(ioaddr + DMA_AXI_BUS_MODE);

        pr_info("dwmac1000: Master AXI performs %s burst length\n",
                !(value & DMA_AXI_UNDEF) ? "fixed" : "any");

        if (axi->axi_lpi_en)
                value |= DMA_AXI_EN_LPI;
        if (axi->axi_xit_frm)
                value |= DMA_AXI_LPI_XIT_FRM;

        value = u32_replace_bits(value, axi->axi_wr_osr_lmt,
                                 DMA_AXI_WR_OSR_LMT);
        value = u32_replace_bits(value, axi->axi_rd_osr_lmt,
                                 DMA_AXI_RD_OSR_LMT);

        /* Depending on the UNDEF bit the Master AXI will perform any burst
         * length according to the BLEN programmed (by default all BLEN are
         * set). Note that the UNDEF bit is readonly, and is the inverse of
         * Bus Mode bit 16.
         */
        value = (value & ~DMA_AXI_BLEN_MASK) | axi->axi_blen_regval;

        writel(value, ioaddr + DMA_AXI_BUS_MODE);
}

static void dwmac1000_dma_init_channel(struct stmmac_priv *priv,
                                       void __iomem *ioaddr,
                                       struct stmmac_dma_cfg *dma_cfg, u32 chan)
{
        int txpbl = dma_cfg->txpbl ?: dma_cfg->pbl;
        int rxpbl = dma_cfg->rxpbl ?: dma_cfg->pbl;
        u32 value;

        value = readl(ioaddr + DMA_CHAN_BUS_MODE(chan));

        /* Set the DMA PBL (Programmable Burst Length) mode.
         *
         * Note: before stmmac core 3.50 this mode bit was 4xPBL, and
         * post 3.5 mode bit acts as 8*PBL.
         */
        if (dma_cfg->pblx8)
                value |= DMA_BUS_MODE_MAXPBL;
        value |= DMA_BUS_MODE_USP;
        value = u32_replace_bits(value, txpbl, DMA_BUS_MODE_PBL_MASK);
        value = u32_replace_bits(value, rxpbl, DMA_BUS_MODE_RPBL_MASK);

        /* Set the Fixed burst mode */
        if (dma_cfg->fixed_burst)
                value |= DMA_BUS_MODE_FB;

        /* Mixed Burst has no effect when fb is set */
        if (dma_cfg->mixed_burst)
                value |= DMA_BUS_MODE_MB;

        if (dma_cfg->atds)
                value |= DMA_BUS_MODE_ATDS;

        if (dma_cfg->aal)
                value |= DMA_BUS_MODE_AAL;

        writel(value, ioaddr + DMA_CHAN_BUS_MODE(chan));

        /* Mask interrupts by writing to CSR7 */
        writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_CHAN_INTR_ENA(chan));
}

static void dwmac1000_dma_init_rx(struct stmmac_priv *priv,
                                  void __iomem *ioaddr,
                                  struct stmmac_dma_cfg *dma_cfg,
                                  dma_addr_t dma_rx_phy, u32 chan)
{
        /* RX descriptor base address list must be written into DMA CSR3 */
        writel(lower_32_bits(dma_rx_phy), ioaddr + DMA_CHAN_RCV_BASE_ADDR(chan));
}

static void dwmac1000_dma_init_tx(struct stmmac_priv *priv,
                                  void __iomem *ioaddr,
                                  struct stmmac_dma_cfg *dma_cfg,
                                  dma_addr_t dma_tx_phy, u32 chan)
{
        /* TX descriptor base address list must be written into DMA CSR4 */
        writel(lower_32_bits(dma_tx_phy), ioaddr + DMA_CHAN_TX_BASE_ADDR(chan));
}

static u32 dwmac1000_configure_fc(u32 csr6, int rxfifosz)
{
        csr6 &= ~DMA_CONTROL_RFA_MASK;
        csr6 &= ~DMA_CONTROL_RFD_MASK;

        /* Leave flow control disabled if receive fifo size is less than
         * 4K or 0. Otherwise, send XOFF when fifo is 1K less than full,
         * and send XON when 2K less than full.
         */
        if (rxfifosz < 4096) {
                csr6 &= ~DMA_CONTROL_EFC;
                pr_debug("GMAC: disabling flow control, rxfifo too small(%d)\n",
                         rxfifosz);
        } else {
                csr6 |= DMA_CONTROL_EFC;
                csr6 |= RFA_FULL_MINUS_1K;
                csr6 |= RFD_FULL_MINUS_2K;
        }
        return csr6;
}

static void dwmac1000_dma_operation_mode_rx(struct stmmac_priv *priv,
                                            void __iomem *ioaddr, int mode,
                                            u32 channel, int fifosz, u8 qmode)
{
        u32 csr6 = readl(ioaddr + DMA_CHAN_CONTROL(channel));

        if (mode == SF_DMA_MODE) {
                pr_debug("GMAC: enable RX store and forward mode\n");
                csr6 |= DMA_CONTROL_RSF | DMA_CONTROL_DFF;
        } else {
                pr_debug("GMAC: disable RX SF mode (threshold %d)\n", mode);
                csr6 &= ~(DMA_CONTROL_RSF | DMA_CONTROL_DFF);
                csr6 &= DMA_CONTROL_TC_RX_MASK;
                if (mode <= 32)
                        csr6 |= DMA_CONTROL_RTC_32;
                else if (mode <= 64)
                        csr6 |= DMA_CONTROL_RTC_64;
                else if (mode <= 96)
                        csr6 |= DMA_CONTROL_RTC_96;
                else
                        csr6 |= DMA_CONTROL_RTC_128;
        }

        /* Configure flow control based on rx fifo size */
        csr6 = dwmac1000_configure_fc(csr6, fifosz);

        writel(csr6, ioaddr + DMA_CHAN_CONTROL(channel));
}

static void dwmac1000_dma_operation_mode_tx(struct stmmac_priv *priv,
                                            void __iomem *ioaddr, int mode,
                                            u32 channel, int fifosz, u8 qmode)
{
        u32 csr6 = readl(ioaddr + DMA_CHAN_CONTROL(channel));

        if (mode == SF_DMA_MODE) {
                pr_debug("GMAC: enable TX store and forward mode\n");
                /* Transmit COE type 2 cannot be done in cut-through mode. */
                csr6 |= DMA_CONTROL_TSF;
                /* Operating on second frame increase the performance
                 * especially when transmit store-and-forward is used.
                 */
                csr6 |= DMA_CONTROL_OSF;
        } else {
                pr_debug("GMAC: disabling TX SF (threshold %d)\n", mode);
                csr6 &= ~DMA_CONTROL_TSF;
                csr6 &= DMA_CONTROL_TC_TX_MASK;
                /* Set the transmit threshold */
                if (mode <= 32)
                        csr6 |= DMA_CONTROL_TTC_32;
                else if (mode <= 64)
                        csr6 |= DMA_CONTROL_TTC_64;
                else if (mode <= 128)
                        csr6 |= DMA_CONTROL_TTC_128;
                else if (mode <= 192)
                        csr6 |= DMA_CONTROL_TTC_192;
                else
                        csr6 |= DMA_CONTROL_TTC_256;
        }

        writel(csr6, ioaddr + DMA_CHAN_CONTROL(channel));
}

static void dwmac1000_dump_dma_regs(struct stmmac_priv *priv,
                                    void __iomem *ioaddr, u32 *reg_space)
{
        int i;

        for (i = 0; i < NUM_DWMAC1000_DMA_REGS; i++)
                if ((i < 12) || (i > 17))
                        reg_space[DMA_BUS_MODE / 4 + i] =
                                readl(ioaddr + DMA_BUS_MODE + i * 4);
}

static int dwmac1000_get_hw_feature(void __iomem *ioaddr,
                                    struct dma_features *dma_cap)
{
        u32 hw_cap = readl(ioaddr + DMA_HW_FEATURE);

        if (!hw_cap) {
                /* 0x00000000 is the value read on old hardware that does not
                 * implement this register
                 */
                return -EOPNOTSUPP;
        }

        dma_cap->mbps_10_100 = (hw_cap & DMA_HW_FEAT_MIISEL);
        dma_cap->mbps_1000 = (hw_cap & DMA_HW_FEAT_GMIISEL) >> 1;
        dma_cap->half_duplex = (hw_cap & DMA_HW_FEAT_HDSEL) >> 2;
        dma_cap->hash_filter = (hw_cap & DMA_HW_FEAT_HASHSEL) >> 4;
        dma_cap->multi_addr = (hw_cap & DMA_HW_FEAT_ADDMAC) >> 5;
        dma_cap->pcs = (hw_cap & DMA_HW_FEAT_PCSSEL) >> 6;
        dma_cap->sma_mdio = (hw_cap & DMA_HW_FEAT_SMASEL) >> 8;
        dma_cap->pmt_remote_wake_up = (hw_cap & DMA_HW_FEAT_RWKSEL) >> 9;
        dma_cap->pmt_magic_frame = (hw_cap & DMA_HW_FEAT_MGKSEL) >> 10;
        /* MMC */
        dma_cap->rmon = (hw_cap & DMA_HW_FEAT_MMCSEL) >> 11;
        /* IEEE 1588-2002 */
        dma_cap->time_stamp =
            (hw_cap & DMA_HW_FEAT_TSVER1SEL) >> 12;
        /* IEEE 1588-2008 */
        dma_cap->atime_stamp = (hw_cap & DMA_HW_FEAT_TSVER2SEL) >> 13;
        /* 802.3az - Energy-Efficient Ethernet (EEE) */
        dma_cap->eee = (hw_cap & DMA_HW_FEAT_EEESEL) >> 14;
        dma_cap->av = (hw_cap & DMA_HW_FEAT_AVSEL) >> 15;
        /* TX and RX csum */
        dma_cap->tx_coe = (hw_cap & DMA_HW_FEAT_TXCOESEL) >> 16;
        dma_cap->rx_coe_type1 = (hw_cap & DMA_HW_FEAT_RXTYP1COE) >> 17;
        dma_cap->rx_coe_type2 = (hw_cap & DMA_HW_FEAT_RXTYP2COE) >> 18;
        dma_cap->rxfifo_over_2048 = (hw_cap & DMA_HW_FEAT_RXFIFOSIZE) >> 19;
        /* TX and RX number of channels */
        dma_cap->number_rx_channel = (hw_cap & DMA_HW_FEAT_RXCHCNT) >> 20;
        dma_cap->number_tx_channel = (hw_cap & DMA_HW_FEAT_TXCHCNT) >> 22;
        /* Alternate (enhanced) DESC mode */
        dma_cap->enh_desc = (hw_cap & DMA_HW_FEAT_ENHDESSEL) >> 24;

        dma_cap->actphyif = FIELD_GET(DMA_HW_FEAT_ACTPHYIF, hw_cap);

        return 0;
}

static void dwmac1000_rx_watchdog(struct stmmac_priv *priv,
                                  void __iomem *ioaddr, u32 riwt, u32 queue)
{
        writel(riwt, ioaddr + DMA_CHAN_RX_WATCHDOG(queue));
}

const struct stmmac_dma_ops dwmac1000_dma_ops = {
        .reset = dwmac_dma_reset,
        .init_chan = dwmac1000_dma_init_channel,
        .init_rx_chan = dwmac1000_dma_init_rx,
        .init_tx_chan = dwmac1000_dma_init_tx,
        .axi = dwmac1000_dma_axi,
        .dump_regs = dwmac1000_dump_dma_regs,
        .dma_rx_mode = dwmac1000_dma_operation_mode_rx,
        .dma_tx_mode = dwmac1000_dma_operation_mode_tx,
        .enable_dma_transmission = dwmac_enable_dma_transmission,
        .enable_dma_reception = dwmac_enable_dma_reception,
        .enable_dma_irq = dwmac_enable_dma_irq,
        .disable_dma_irq = dwmac_disable_dma_irq,
        .start_tx = dwmac_dma_start_tx,
        .stop_tx = dwmac_dma_stop_tx,
        .start_rx = dwmac_dma_start_rx,
        .stop_rx = dwmac_dma_stop_rx,
        .dma_interrupt = dwmac_dma_interrupt,
        .get_hw_feature = dwmac1000_get_hw_feature,
        .rx_watchdog = dwmac1000_rx_watchdog,
};
EXPORT_SYMBOL_GPL(dwmac1000_dma_ops);