root/drivers/mtd/nand/raw/mxic_nand.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2019 Macronix International Co., Ltd.
 *
 * Author:
 *      Mason Yang <masonccyang@mxic.com.tw>
 */

#include <linux/clk.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand-ecc-sw-hamming.h>
#include <linux/mtd/rawnand.h>
#include <linux/platform_device.h>

#include "internals.h"

#define HC_CFG                  0x0
#define HC_CFG_IF_CFG(x)        ((x) << 27)
#define HC_CFG_DUAL_SLAVE       BIT(31)
#define HC_CFG_INDIVIDUAL       BIT(30)
#define HC_CFG_NIO(x)           (((x) / 4) << 27)
#define HC_CFG_TYPE(s, t)       ((t) << (23 + ((s) * 2)))
#define HC_CFG_TYPE_SPI_NOR     0
#define HC_CFG_TYPE_SPI_NAND    1
#define HC_CFG_TYPE_SPI_RAM     2
#define HC_CFG_TYPE_RAW_NAND    3
#define HC_CFG_SLV_ACT(x)       ((x) << 21)
#define HC_CFG_CLK_PH_EN        BIT(20)
#define HC_CFG_CLK_POL_INV      BIT(19)
#define HC_CFG_BIG_ENDIAN       BIT(18)
#define HC_CFG_DATA_PASS        BIT(17)
#define HC_CFG_IDLE_SIO_LVL(x)  ((x) << 16)
#define HC_CFG_MAN_START_EN     BIT(3)
#define HC_CFG_MAN_START        BIT(2)
#define HC_CFG_MAN_CS_EN        BIT(1)
#define HC_CFG_MAN_CS_ASSERT    BIT(0)

#define INT_STS                 0x4
#define INT_STS_EN              0x8
#define INT_SIG_EN              0xc
#define INT_STS_ALL             GENMASK(31, 0)
#define INT_RDY_PIN             BIT(26)
#define INT_RDY_SR              BIT(25)
#define INT_LNR_SUSP            BIT(24)
#define INT_ECC_ERR             BIT(17)
#define INT_CRC_ERR             BIT(16)
#define INT_LWR_DIS             BIT(12)
#define INT_LRD_DIS             BIT(11)
#define INT_SDMA_INT            BIT(10)
#define INT_DMA_FINISH          BIT(9)
#define INT_RX_NOT_FULL         BIT(3)
#define INT_RX_NOT_EMPTY        BIT(2)
#define INT_TX_NOT_FULL         BIT(1)
#define INT_TX_EMPTY            BIT(0)

#define HC_EN                   0x10
#define HC_EN_BIT               BIT(0)

#define TXD(x)                  (0x14 + ((x) * 4))
#define RXD                     0x24

#define SS_CTRL(s)              (0x30 + ((s) * 4))
#define LRD_CFG                 0x44
#define LWR_CFG                 0x80
#define RWW_CFG                 0x70
#define OP_READ                 BIT(23)
#define OP_DUMMY_CYC(x)         ((x) << 17)
#define OP_ADDR_BYTES(x)        ((x) << 14)
#define OP_CMD_BYTES(x)         (((x) - 1) << 13)
#define OP_OCTA_CRC_EN          BIT(12)
#define OP_DQS_EN               BIT(11)
#define OP_ENHC_EN              BIT(10)
#define OP_PREAMBLE_EN          BIT(9)
#define OP_DATA_DDR             BIT(8)
#define OP_DATA_BUSW(x)         ((x) << 6)
#define OP_ADDR_DDR             BIT(5)
#define OP_ADDR_BUSW(x)         ((x) << 3)
#define OP_CMD_DDR              BIT(2)
#define OP_CMD_BUSW(x)          (x)
#define OP_BUSW_1               0
#define OP_BUSW_2               1
#define OP_BUSW_4               2
#define OP_BUSW_8               3

#define OCTA_CRC                0x38
#define OCTA_CRC_IN_EN(s)       BIT(3 + ((s) * 16))
#define OCTA_CRC_CHUNK(s, x)    ((fls((x) / 32)) << (1 + ((s) * 16)))
#define OCTA_CRC_OUT_EN(s)      BIT(0 + ((s) * 16))

#define ONFI_DIN_CNT(s)         (0x3c + (s))

#define LRD_CTRL                0x48
#define RWW_CTRL                0x74
#define LWR_CTRL                0x84
#define LMODE_EN                BIT(31)
#define LMODE_SLV_ACT(x)        ((x) << 21)
#define LMODE_CMD1(x)           ((x) << 8)
#define LMODE_CMD0(x)           (x)

#define LRD_ADDR                0x4c
#define LWR_ADDR                0x88
#define LRD_RANGE               0x50
#define LWR_RANGE               0x8c

#define AXI_SLV_ADDR            0x54

#define DMAC_RD_CFG             0x58
#define DMAC_WR_CFG             0x94
#define DMAC_CFG_PERIPH_EN      BIT(31)
#define DMAC_CFG_ALLFLUSH_EN    BIT(30)
#define DMAC_CFG_LASTFLUSH_EN   BIT(29)
#define DMAC_CFG_QE(x)          (((x) + 1) << 16)
#define DMAC_CFG_BURST_LEN(x)   (((x) + 1) << 12)
#define DMAC_CFG_BURST_SZ(x)    ((x) << 8)
#define DMAC_CFG_DIR_READ       BIT(1)
#define DMAC_CFG_START          BIT(0)

#define DMAC_RD_CNT             0x5c
#define DMAC_WR_CNT             0x98

#define SDMA_ADDR               0x60

#define DMAM_CFG                0x64
#define DMAM_CFG_START          BIT(31)
#define DMAM_CFG_CONT           BIT(30)
#define DMAM_CFG_SDMA_GAP(x)    (fls((x) / 8192) << 2)
#define DMAM_CFG_DIR_READ       BIT(1)
#define DMAM_CFG_EN             BIT(0)

#define DMAM_CNT                0x68

#define LNR_TIMER_TH            0x6c

#define RDM_CFG0                0x78
#define RDM_CFG0_POLY(x)        (x)

#define RDM_CFG1                0x7c
#define RDM_CFG1_RDM_EN         BIT(31)
#define RDM_CFG1_SEED(x)        (x)

#define LWR_SUSP_CTRL           0x90
#define LWR_SUSP_CTRL_EN        BIT(31)

#define DMAS_CTRL               0x9c
#define DMAS_CTRL_EN            BIT(31)
#define DMAS_CTRL_DIR_READ      BIT(30)

#define DATA_STROB              0xa0
#define DATA_STROB_EDO_EN       BIT(2)
#define DATA_STROB_INV_POL      BIT(1)
#define DATA_STROB_DELAY_2CYC   BIT(0)

#define IDLY_CODE(x)            (0xa4 + ((x) * 4))
#define IDLY_CODE_VAL(x, v)     ((v) << (((x) % 4) * 8))

#define GPIO                    0xc4
#define GPIO_PT(x)              BIT(3 + ((x) * 16))
#define GPIO_RESET(x)           BIT(2 + ((x) * 16))
#define GPIO_HOLDB(x)           BIT(1 + ((x) * 16))
#define GPIO_WPB(x)             BIT((x) * 16)

#define HC_VER                  0xd0

#define HW_TEST(x)              (0xe0 + ((x) * 4))

#define MXIC_NFC_MAX_CLK_HZ     50000000
#define IRQ_TIMEOUT             1000

struct mxic_nand_ctlr {
        struct clk *ps_clk;
        struct clk *send_clk;
        struct clk *send_dly_clk;
        struct completion complete;
        void __iomem *regs;
        struct nand_controller controller;
        struct device *dev;
        struct nand_chip chip;
};

static int mxic_nfc_clk_enable(struct mxic_nand_ctlr *nfc)
{
        int ret;

        ret = clk_prepare_enable(nfc->ps_clk);
        if (ret)
                return ret;

        ret = clk_prepare_enable(nfc->send_clk);
        if (ret)
                goto err_ps_clk;

        ret = clk_prepare_enable(nfc->send_dly_clk);
        if (ret)
                goto err_send_dly_clk;

        return ret;

err_send_dly_clk:
        clk_disable_unprepare(nfc->send_clk);
err_ps_clk:
        clk_disable_unprepare(nfc->ps_clk);

        return ret;
}

static void mxic_nfc_clk_disable(struct mxic_nand_ctlr *nfc)
{
        clk_disable_unprepare(nfc->send_clk);
        clk_disable_unprepare(nfc->send_dly_clk);
        clk_disable_unprepare(nfc->ps_clk);
}

static void mxic_nfc_set_input_delay(struct mxic_nand_ctlr *nfc, u8 idly_code)
{
        writel(IDLY_CODE_VAL(0, idly_code) |
               IDLY_CODE_VAL(1, idly_code) |
               IDLY_CODE_VAL(2, idly_code) |
               IDLY_CODE_VAL(3, idly_code),
               nfc->regs + IDLY_CODE(0));
        writel(IDLY_CODE_VAL(4, idly_code) |
               IDLY_CODE_VAL(5, idly_code) |
               IDLY_CODE_VAL(6, idly_code) |
               IDLY_CODE_VAL(7, idly_code),
               nfc->regs + IDLY_CODE(1));
}

static int mxic_nfc_clk_setup(struct mxic_nand_ctlr *nfc, unsigned long freq)
{
        int ret;

        ret = clk_set_rate(nfc->send_clk, freq);
        if (ret)
                return ret;

        ret = clk_set_rate(nfc->send_dly_clk, freq);
        if (ret)
                return ret;

        /*
         * A constant delay range from 0x0 ~ 0x1F for input delay,
         * the unit is 78 ps, the max input delay is 2.418 ns.
         */
        mxic_nfc_set_input_delay(nfc, 0xf);

        /*
         * Phase degree = 360 * freq * output-delay
         * where output-delay is a constant value 1 ns in FPGA.
         *
         * Get Phase degree = 360 * freq * 1 ns
         *                  = 360 * freq * 1 sec / 1000000000
         *                  = 9 * freq / 25000000
         */
        ret = clk_set_phase(nfc->send_dly_clk, 9 * freq / 25000000);
        if (ret)
                return ret;

        return 0;
}

static int mxic_nfc_set_freq(struct mxic_nand_ctlr *nfc, unsigned long freq)
{
        int ret;

        if (freq > MXIC_NFC_MAX_CLK_HZ)
                freq = MXIC_NFC_MAX_CLK_HZ;

        mxic_nfc_clk_disable(nfc);
        ret = mxic_nfc_clk_setup(nfc, freq);
        if (ret)
                return ret;

        ret = mxic_nfc_clk_enable(nfc);
        if (ret)
                return ret;

        return 0;
}

static irqreturn_t mxic_nfc_isr(int irq, void *dev_id)
{
        struct mxic_nand_ctlr *nfc = dev_id;
        u32 sts;

        sts = readl(nfc->regs + INT_STS);
        if (sts & INT_RDY_PIN)
                complete(&nfc->complete);
        else
                return IRQ_NONE;

        return IRQ_HANDLED;
}

static void mxic_nfc_hw_init(struct mxic_nand_ctlr *nfc)
{
        writel(HC_CFG_NIO(8) | HC_CFG_TYPE(1, HC_CFG_TYPE_RAW_NAND) |
               HC_CFG_SLV_ACT(0) | HC_CFG_MAN_CS_EN |
               HC_CFG_IDLE_SIO_LVL(1), nfc->regs + HC_CFG);
        writel(INT_STS_ALL, nfc->regs + INT_STS_EN);
        writel(INT_RDY_PIN, nfc->regs + INT_SIG_EN);
        writel(0x0, nfc->regs + ONFI_DIN_CNT(0));
        writel(0, nfc->regs + LRD_CFG);
        writel(0, nfc->regs + LRD_CTRL);
        writel(0x0, nfc->regs + HC_EN);
}

static void mxic_nfc_cs_enable(struct mxic_nand_ctlr *nfc)
{
        writel(readl(nfc->regs + HC_CFG) | HC_CFG_MAN_CS_EN,
               nfc->regs + HC_CFG);
        writel(HC_CFG_MAN_CS_ASSERT | readl(nfc->regs + HC_CFG),
               nfc->regs + HC_CFG);
}

static void mxic_nfc_cs_disable(struct mxic_nand_ctlr *nfc)
{
        writel(~HC_CFG_MAN_CS_ASSERT & readl(nfc->regs + HC_CFG),
               nfc->regs + HC_CFG);
}

static int  mxic_nfc_wait_ready(struct nand_chip *chip)
{
        struct mxic_nand_ctlr *nfc = nand_get_controller_data(chip);
        int ret;

        ret = wait_for_completion_timeout(&nfc->complete,
                                          msecs_to_jiffies(IRQ_TIMEOUT));
        if (!ret) {
                dev_err(nfc->dev, "nand device timeout\n");
                return -ETIMEDOUT;
        }

        return 0;
}

static int mxic_nfc_data_xfer(struct mxic_nand_ctlr *nfc, const void *txbuf,
                              void *rxbuf, unsigned int len)
{
        unsigned int pos = 0;

        while (pos < len) {
                unsigned int nbytes = len - pos;
                u32 data = 0xffffffff;
                u32 sts;
                int ret;

                if (nbytes > 4)
                        nbytes = 4;

                if (txbuf)
                        memcpy(&data, txbuf + pos, nbytes);

                ret = readl_poll_timeout(nfc->regs + INT_STS, sts,
                                         sts & INT_TX_EMPTY, 0, USEC_PER_SEC);
                if (ret)
                        return ret;

                writel(data, nfc->regs + TXD(nbytes % 4));

                ret = readl_poll_timeout(nfc->regs + INT_STS, sts,
                                         sts & INT_TX_EMPTY, 0, USEC_PER_SEC);
                if (ret)
                        return ret;

                ret = readl_poll_timeout(nfc->regs + INT_STS, sts,
                                         sts & INT_RX_NOT_EMPTY, 0,
                                         USEC_PER_SEC);
                if (ret)
                        return ret;

                data = readl(nfc->regs + RXD);
                if (rxbuf) {
                        data >>= (8 * (4 - nbytes));
                        memcpy(rxbuf + pos, &data, nbytes);
                }
                if (readl(nfc->regs + INT_STS) & INT_RX_NOT_EMPTY)
                        dev_warn(nfc->dev, "RX FIFO not empty\n");

                pos += nbytes;
        }

        return 0;
}

static int mxic_nfc_exec_op(struct nand_chip *chip,
                            const struct nand_operation *op, bool check_only)
{
        struct mxic_nand_ctlr *nfc = nand_get_controller_data(chip);
        const struct nand_op_instr *instr = NULL;
        int ret = 0;
        unsigned int op_id;

        if (check_only)
                return 0;

        mxic_nfc_cs_enable(nfc);
        init_completion(&nfc->complete);
        for (op_id = 0; op_id < op->ninstrs; op_id++) {
                instr = &op->instrs[op_id];

                switch (instr->type) {
                case NAND_OP_CMD_INSTR:
                        writel(0, nfc->regs + HC_EN);
                        writel(HC_EN_BIT, nfc->regs + HC_EN);
                        writel(OP_CMD_BUSW(OP_BUSW_8) |  OP_DUMMY_CYC(0x3F) |
                               OP_CMD_BYTES(0), nfc->regs + SS_CTRL(0));

                        ret = mxic_nfc_data_xfer(nfc,
                                                 &instr->ctx.cmd.opcode,
                                                 NULL, 1);
                        break;

                case NAND_OP_ADDR_INSTR:
                        writel(OP_ADDR_BUSW(OP_BUSW_8) | OP_DUMMY_CYC(0x3F) |
                               OP_ADDR_BYTES(instr->ctx.addr.naddrs),
                               nfc->regs + SS_CTRL(0));
                        ret = mxic_nfc_data_xfer(nfc,
                                                 instr->ctx.addr.addrs, NULL,
                                                 instr->ctx.addr.naddrs);
                        break;

                case NAND_OP_DATA_IN_INSTR:
                        writel(0x0, nfc->regs + ONFI_DIN_CNT(0));
                        writel(OP_DATA_BUSW(OP_BUSW_8) | OP_DUMMY_CYC(0x3F) |
                               OP_READ, nfc->regs + SS_CTRL(0));
                        ret = mxic_nfc_data_xfer(nfc, NULL,
                                                 instr->ctx.data.buf.in,
                                                 instr->ctx.data.len);
                        break;

                case NAND_OP_DATA_OUT_INSTR:
                        writel(instr->ctx.data.len,
                               nfc->regs + ONFI_DIN_CNT(0));
                        writel(OP_DATA_BUSW(OP_BUSW_8) | OP_DUMMY_CYC(0x3F),
                               nfc->regs + SS_CTRL(0));
                        ret = mxic_nfc_data_xfer(nfc,
                                                 instr->ctx.data.buf.out, NULL,
                                                 instr->ctx.data.len);
                        break;

                case NAND_OP_WAITRDY_INSTR:
                        ret = mxic_nfc_wait_ready(chip);
                        break;
                }
        }
        mxic_nfc_cs_disable(nfc);

        return ret;
}

static int mxic_nfc_setup_interface(struct nand_chip *chip, int chipnr,
                                    const struct nand_interface_config *conf)
{
        struct mxic_nand_ctlr *nfc = nand_get_controller_data(chip);
        const struct nand_sdr_timings *sdr;
        unsigned long freq;
        int ret;

        sdr = nand_get_sdr_timings(conf);
        if (IS_ERR(sdr))
                return PTR_ERR(sdr);

        if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
                return 0;

        freq = NSEC_PER_SEC / (sdr->tRC_min / 1000);

        ret =  mxic_nfc_set_freq(nfc, freq);
        if (ret)
                dev_err(nfc->dev, "set freq:%ld failed\n", freq);

        if (sdr->tRC_min < 30000)
                writel(DATA_STROB_EDO_EN, nfc->regs + DATA_STROB);

        return 0;
}

static const struct nand_controller_ops mxic_nand_controller_ops = {
        .exec_op = mxic_nfc_exec_op,
        .setup_interface = mxic_nfc_setup_interface,
};

static int mxic_nfc_probe(struct platform_device *pdev)
{
        struct device_node *nand_np, *np = pdev->dev.of_node;
        struct mtd_info *mtd;
        struct mxic_nand_ctlr *nfc;
        struct nand_chip *nand_chip;
        int err;
        int irq;

        nfc = devm_kzalloc(&pdev->dev, sizeof(struct mxic_nand_ctlr),
                           GFP_KERNEL);
        if (!nfc)
                return -ENOMEM;

        nfc->ps_clk = devm_clk_get(&pdev->dev, "ps");
        if (IS_ERR(nfc->ps_clk))
                return PTR_ERR(nfc->ps_clk);

        nfc->send_clk = devm_clk_get(&pdev->dev, "send");
        if (IS_ERR(nfc->send_clk))
                return PTR_ERR(nfc->send_clk);

        nfc->send_dly_clk = devm_clk_get(&pdev->dev, "send_dly");
        if (IS_ERR(nfc->send_dly_clk))
                return PTR_ERR(nfc->send_dly_clk);

        nfc->regs = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(nfc->regs))
                return PTR_ERR(nfc->regs);

        nand_chip = &nfc->chip;
        mtd = nand_to_mtd(nand_chip);
        mtd->dev.parent = &pdev->dev;

        for_each_child_of_node(np, nand_np)
                nand_set_flash_node(nand_chip, nand_np);

        nand_chip->priv = nfc;
        nfc->dev = &pdev->dev;
        nfc->controller.ops = &mxic_nand_controller_ops;
        nand_controller_init(&nfc->controller);
        nand_chip->controller = &nfc->controller;

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;

        mxic_nfc_hw_init(nfc);

        err = devm_request_irq(&pdev->dev, irq, mxic_nfc_isr,
                               0, "mxic-nfc", nfc);
        if (err)
                goto fail;

        err = nand_scan(nand_chip, 1);
        if (err)
                goto fail;

        err = mtd_device_register(mtd, NULL, 0);
        if (err)
                goto fail;

        platform_set_drvdata(pdev, nfc);
        return 0;

fail:
        mxic_nfc_clk_disable(nfc);
        return err;
}

static void mxic_nfc_remove(struct platform_device *pdev)
{
        struct mxic_nand_ctlr *nfc = platform_get_drvdata(pdev);
        struct nand_chip *chip = &nfc->chip;
        int ret;

        ret = mtd_device_unregister(nand_to_mtd(chip));
        WARN_ON(ret);
        nand_cleanup(chip);

        mxic_nfc_clk_disable(nfc);
}

static const struct of_device_id mxic_nfc_of_ids[] = {
        { .compatible = "mxic,multi-itfc-v009-nand-controller", },
        {},
};
MODULE_DEVICE_TABLE(of, mxic_nfc_of_ids);

static struct platform_driver mxic_nfc_driver = {
        .probe = mxic_nfc_probe,
        .remove = mxic_nfc_remove,
        .driver = {
                .name = "mxic-nfc",
                .of_match_table = mxic_nfc_of_ids,
        },
};
module_platform_driver(mxic_nfc_driver);

MODULE_AUTHOR("Mason Yang <masonccyang@mxic.com.tw>");
MODULE_DESCRIPTION("Macronix raw NAND controller driver");
MODULE_LICENSE("GPL v2");