/*
 * Amlogic Meson SPI flash controller(SPIFC)
 *
 * Copyright (C) 2017 Amlogic Corporation
 *
 * Licensed under the GPL-2 or later.
 *
 */

#include <common.h>
#include <dm.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/gpio.h>
#include <asm/arch/secure_apb.h>
#include <spi.h>
#include <amlogic/spifc.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>
#include <dm/root.h>
#include <dm/lists.h>
#include <dm/util.h>
#include <fdtdec.h>

DECLARE_GLOBAL_DATA_PTR;

unsigned int spifc_flags = 0;
#define spifc_dbg(fmt, args...) { \
	if (spifc_flags & 1) \
		printf("%s: " fmt, __func__, ## args); \
}
#define spifc_dbg_buff(_buf, _len, _i) { \
	if (spifc_flags & 2) { \
		for (_i=0; _i<_len; _i++) \
			printf("0x%x,", _buf[_i]); \
		printf("\n%s: total %d\n", __func__, _len); \
	} \
}

struct spifc_regs {
	u32 cmd;
		#define SPI_FLASH_READ    31
		#define SPI_FLASH_WREN    30
		#define SPI_FLASH_WRDI    29
		#define SPI_FLASH_RDID    28
		#define SPI_FLASH_RDSR    27
		#define SPI_FLASH_WRSR    26
		#define SPI_FLASH_PP      25
		#define SPI_FLASH_SE      24
		#define SPI_FLASH_BE      23
		#define SPI_FLASH_CE      22
		#define SPI_FLASH_DP      21
		#define SPI_FLASH_RES     20
		#define SPI_HPM           19
		#define SPI_FLASH_USR     18
		#define SPI_FLASH_USR_ADDR 15
		#define SPI_FLASH_USR_DUMMY 14
		#define SPI_FLASH_USR_DIN   13
		#define SPI_FLASH_USR_DOUT   12
		#define SPI_FLASH_USR_DUMMY_BLEN   10
		#define SPI_FLASH_USR_CMD     0
	u32 addr;
		#define SPI_FLASH_BYTES_LEN 24
		#define SPI_FLASH_ADDR_START 0
	u32 ctrl;
		#define FAST_READ_QUAD_IO 24
		#define FAST_READ_DUAL_IO 23
		#define FAST_READ_QUAD_OUT 20
		#define SPI_ENABLE_AHB    17
		#define SPI_SST_AAI       16
		#define SPI_RES_RID       15
		#define FAST_READ_DUAL_OUT 14
		#define SPI_READ_READ_EN  13
		#define SPI_CLK_DIV0      12
		#define SPI_CLKCNT_N      8
		#define SPI_CLKCNT_H      4
		#define SPI_CLKCNT_L      0
	u32 ctrl1;
	u32 status;
	u32 ctrl2;
	u32 clock;
		#define SPI_CLK_DIV0_NEW  31
		#define SPI_PRE_SCALE_DIV 18
		#define SPI_CLKCNT_N_NEW  12
		#define SPI_CLKCNT_H_NEW  6
		#define SPI_CLKCNT_L_NEW  0
	u32 user;
		#define USER_CMD_INCLUDE_CMD        31
		#define USER_CMD_INCLUDE_ADDR       30
		#define USER_CMD_INCLUDE_DUMMY      29
		#define USER_CMD_INCLUDE_DIN        28
		#define USER_CMD_INCLUDE_DOUT       27
		#define USER_CMD_DUMMY_IDLE         26
		#define USER_CMD_HIGHPART_DURING_SPI_DOUT_STAGE      25
		#define USER_CMD_HIGHPART_DURING_SPI_DIN_STAGE       24
		#define USER_CMD_EXT_HOLD_IN_STA_PREP  23
		#define USER_CMD_EXT_HOLD_IN_STA_CMD   22
		#define USER_CMD_EXT_HOLD_IN_STA_ADDR  21
		#define USER_CMD_EXT_HOLD_IN_STA_DUMMY 20
		#define USER_CMD_EXT_HOLD_IN_STA_DIN   19
		#define USER_CMD_EXT_HOLD_IN_STA_DOUT  18
		#define USER_CMD_EXT_HOLD_POLARITY  17
		#define SINGLE_DIO_MODE             16
		#define FAST_WRITE_QUAD_IO          15
		#define FAST_WRITE_DUAL_IO          14
		#define FAST_WRITE_QUAD_OUT         13
		#define FAST_WRITE_DUAL_OUT         12
		#define WRITE_BYTE_ORDER            11
		#define READ_BYTE_ORDER             10
		#define AHB_ENDIAN_MODE             8
		#define MASTER_CLK_EDGE             7
		#define SLAVE_CLK_EDGE              6
		#define CS_VALID_IN_STA_PREP        5
		#define CS_VALID_IN_STA_DONE        4
		#define AHB_READ_APPLY_CONFIG       3
		#define COMPATIBLE_TO_APPOLO        2
		#define AHP_READ_SUPPORT_4BYTE_ADDR 1
		#define EN_DIN_DURING_SPI_DOUT_STAGE    0
	u32 user1;
		#define USER_CMD_ADDR_BITS         26
		#define USER_CMD_DOUT_BITS         17
		#define USER_CMD_DIN_BITS          8
		#define USER_CMD_DUMMY_BITS        0
	u32 user2;
		#define USER_CMD_CMD_BITS          28
		#define USER_CMD_CMD_VALUE         0
	u32 user3;
	u32 user4; //pin register
		#define CS_KEEP_ACTIVE_AFTER_TRANS 30
	u32 slave;
	u32 slave1;
	u32 slave2;
	u32 slave3;
	u32 cache[8];
	u32 buffer[8];
		#define SPIFC_CACHE_SIZE_IN_WORD 16
		#define SPIFC_CACHE_SIZE_IN_BYTE (SPIFC_CACHE_SIZE_IN_WORD<<2)
};


struct spifc_priv {
	struct spifc_regs *regs;
	void *clk;
	void *pinctrl;
	unsigned int speed;
	unsigned int mode;
	unsigned int wordlen;
	unsigned char cmd;
};

/* flash dual/quad read command */
#define FCMD_READ							0x03
#define FCMD_READ_FAST				0x0b
#define FCMD_READ_DUAL_OUT		0x3b
#define FCMD_READ_QUAD_OUT		0x6b
#define FCMD_READ_DUAL_IO			0xbb
#define FCMD_READ_QUAD_IO			0xeb
/* flash quad write command */
#define FCMD_WRITE						0x02
#define FCMD_WRITE_QUAD_OUT		0x32

static void spifc_set_rx_op_mode(
		struct spifc_priv *priv,
		unsigned int slave_mode,
		unsigned char cmd)
{
	unsigned int val;

	val = readl(&priv->regs->ctrl);
	val &= ~((1 << FAST_READ_DUAL_OUT) |
			(1 << FAST_READ_QUAD_OUT) |
			(1 << FAST_READ_DUAL_IO) |
			(1 << FAST_READ_QUAD_IO));

	if (slave_mode & SPI_RX_DUAL) {
		if (cmd == FCMD_READ_DUAL_OUT)
			val |= 1<<FAST_READ_DUAL_OUT;
	}
	if (slave_mode & SPI_RX_QUAD) {
		if (cmd == FCMD_READ_QUAD_OUT)
			val |= 1<<FAST_READ_QUAD_OUT;
	}
	writel(val, &priv->regs->ctrl);

}

static void spifc_set_tx_op_mode(
		struct spifc_priv *priv,
		unsigned int slave_mode,
		unsigned char cmd)
{
	unsigned int val = 0;

	if (slave_mode & SPI_TX_QUAD) {
		if (cmd == FCMD_WRITE_QUAD_OUT)
			val |= 1 << FAST_WRITE_QUAD_OUT;
	}
	writel(val, &priv->regs->user);
}


static int spifc_user_cmd(
	struct spifc_priv *priv,
	u8 cmd, u8 *buf, u8 len)
{
	struct spifc_regs *regs = priv->regs;
	u16 bits = len ? ((len << 3) - 1) : 0;
	u32 addr = 0;

	if (buf)
		addr = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
	spifc_dbg("cmd=0x%x, len=%d, addr=0x%08x\n", cmd, len, addr);
	clrbits_le32(&regs->ctrl,
			(1<<FAST_READ_DUAL_OUT) |
			(1<<FAST_READ_QUAD_OUT) |
			(1<<FAST_READ_DUAL_IO) |
			(1<<FAST_READ_QUAD_IO));
	writel((1 << USER_CMD_INCLUDE_CMD) |
			((!!len) << USER_CMD_INCLUDE_ADDR),
			&regs->user);
	writel((7 << USER_CMD_CMD_BITS) |
			(cmd << USER_CMD_CMD_VALUE),
			&regs->user2);
	writel(bits << USER_CMD_ADDR_BITS, &regs->user1);
	writel(addr << SPI_FLASH_ADDR_START, &regs->addr);
	writel((1 << SPI_FLASH_USR) |
			(cmd << SPI_FLASH_USR_CMD),
			&regs->cmd);
	while ((readl(&regs->cmd) >> SPI_FLASH_USR) & 1);
	return 0;
}

static int spifc_user_cmd_dout(
	struct spifc_priv *priv,
	u8 *buf, int len, unsigned long flags)
{
	struct spifc_regs *regs = priv->regs;
	volatile unsigned int *cache;
	u32 *p;
	int len32, i;

	p = (u32 *)buf;
	cache = (volatile unsigned int *)&regs->cache;
	len32 = (len/4) + !!(len%4);
	for (i=0; i<len32; i++)
		writel(*p++, cache++);

	setbits_le32(&regs->user, 1 << USER_CMD_INCLUDE_DOUT);
	writel(0, &regs->user2);
	writel(((len << 3) - 1) << USER_CMD_DOUT_BITS, &regs->user1);
	writel(0, &regs->addr);
	writel(1 << SPI_FLASH_USR, &regs->cmd);
	while ((readl(&regs->cmd) >> SPI_FLASH_USR) & 1) {}
	spifc_dbg_buff(buf, len, i);
	return 0;
}

static int spifc_user_cmd_din(
	struct spifc_priv *priv,
	u8 *buf, int len, unsigned long flags)
{
	struct spifc_regs *regs = priv->regs;
	volatile unsigned int *cache;
	u32 *p;
	int len32, i;
	u8 temp_buf[SPIFC_CACHE_SIZE_IN_BYTE];

	writel(1 << USER_CMD_INCLUDE_DIN, &regs->user);
	writel(0, &regs->user2);
	writel(((len << 3) - 1) << USER_CMD_DIN_BITS, &regs->user1);
	writel(0, &regs->addr);
	writel(1 << SPI_FLASH_USR, &regs->cmd);
	while ((readl(&regs->cmd) >> SPI_FLASH_USR) & 1);
	p = (u32 *)temp_buf;
	cache = (volatile unsigned int *)&regs->cache;
	len32 = (len/4) + !!(len%4);
	for (i=0; i<len32; i++)
		*p++ = readl(cache++);
	memcpy(buf, temp_buf, len);
	spifc_dbg_buff(buf, len, i);
	return 0;
}

static int spifc_claim_bus(struct udevice *bus)
{
	struct spifc_platdata *plat = dev_get_platdata(bus);
	struct spifc_priv *priv = dev_get_priv(bus);

	spifc_dbg("pinctrl enable\n");
	if (plat->pinctrl_enable)
		plat->pinctrl_enable(priv->pinctrl, 1);
	return 0;
}

static int spifc_release_bus(struct udevice *bus)
{
	struct spifc_platdata *plat = dev_get_platdata(bus);
	struct spifc_priv *priv = dev_get_priv(bus);

	spifc_dbg("pinctrl disable\n");
	if (plat->pinctrl_enable)
		plat->pinctrl_enable(priv->pinctrl, 0);
	return 0;
}

static int spifc_cs_gpios_init(
		struct spifc_priv *priv,
		struct spifc_platdata *plat)
{
	int gpio;
	int i;

	if (!plat->cs_gpios)
		return 0;

	for (i=0; i<plat->num_chipselect; i++) {
		gpio = plat->cs_gpios[i];
		if (gpio_request(gpio, "spifc_cs")) {
			printf("%s: requesting pin %u failed\n", __func__, gpio);
			return -1;
		}
		/* It's unsuitable to set cs high here, but unfortunitely and
		specially for NOR flash, without this setting, it will probe
		failed because of the pullup resistance absence. */
		gpio_direction_output(gpio, 1);
	}
	return 0;
}

static void spifc_chipselect(struct udevice *dev, bool select)
{
	struct udevice *bus = dev->parent;
	struct spifc_platdata *plat = dev_get_platdata(bus);
	struct spi_slave *slave = dev_get_parentdata(dev);
	int cs = slave->cs;
	bool level = slave->mode & SPI_CS_HIGH;

	if (cs >= plat->num_chipselect) {
		printf("cs %d exceed the bus num_chipselect\n", cs);
		return;
	}
	spifc_dbg("%sselect %s(cs=%d)\n", select ? "" : "de", dev->name, cs);
	if (!select)
		level = !level;
	if (plat->cs_gpios) {
		int cs_gpio = plat->cs_gpios[cs];
		gpio_direction_output(cs_gpio, level);
		spifc_dbg("set gpio %d %d\n", cs_gpio, level);
	}
	else {
		printf("auto chipselect TODO\n");
	}
}

static int spifc_set_speed(
		struct udevice *bus,
		uint hz)
{
	struct spifc_platdata *plat = dev_get_platdata(bus);
	struct spifc_priv *priv = dev_get_priv(bus);
	struct spifc_regs *regs = priv->regs;
	u32 div, value;

	if (hz == priv->speed)
		return 0;
	spifc_dbg("set speed to %d\n", hz);
	priv->speed = hz;
	if (plat->clk_enable)
		plat->clk_enable(priv->clk, !!hz);
	if (!hz)
		return 0;

	value = SPIFC_DEFAULT_CLK_RATE;
	if (plat->clk_get_rate)
		value = plat->clk_get_rate(priv->clk);
	div = value / hz;
	if (div < 2)
		div = 2;
#ifdef CONFIG_SPIFC_COMPATIBLE_TO_APPOLO
	if (div > 0x10)
		div = 0x10;
	value = readl(&regs->ctrl);
	value &= ~(0x1fff<<SPI_CLKCNT_L);
	value |= ((div >> 1) - 1) << SPI_CLKCNT_H;
	value |= (div - 1) << SPI_CLKCNT_N;
	value |= (div - 1) << SPI_CLKCNT_L;
	writel(value, &regs->ctrl);
#else
	if (div > 0x40)
		div = 0x40;
	value = ((div >> 1) - 1) << SPI_CLKCNT_H_NEW;
	value |= (div - 1) << SPI_CLKCNT_N_NEW;
	value |= (div - 1) << SPI_CLKCNT_L_NEW;
	writel(value, &regs->clock);
#endif
	spifc_dbg("div=%d, value=0x%x\n", div, value);
	return 0;
}

static int spifc_set_mode(
		struct udevice *bus,
		uint mode)
{
	struct spifc_priv *priv = dev_get_priv(bus);

	if (mode == priv->mode)
		return 0;
	spifc_dbg("fix mode 0 now, TODO 0x%x\n", mode);
	priv->mode = mode;
	return 0;
}

static int spifc_set_wordlen(
		struct udevice *bus,
		unsigned int wordlen)
{
	struct spifc_priv *priv = dev_get_priv(bus);

	if (wordlen == priv->wordlen)
		return 0;
	spifc_dbg("fix 8 now, TODO %d\n", wordlen);
	priv->wordlen = wordlen;
	return 0;
}

static int spifc_xfer(
		struct udevice *dev,
		unsigned int bitlen,
		const void *dout,
		void *din,
		unsigned long flags)
{
	struct udevice *bus = dev->parent;
	struct spi_slave *slave = dev_get_parentdata(dev);
	struct spifc_priv *priv = dev_get_priv(bus);
	u8 *buf;
	int len = bitlen >> 3;
	int lening;
	int ret = 0;

	spifc_dbg("slave %u:%u bitlen %u\n", bus->seq,
			spi_chip_select(dev), bitlen);

	if (bitlen % 8) {
		printf("%s: error bitlen\n", __func__);
		return -EINVAL;
	}
	spifc_set_speed(bus, slave->max_hz);
	spifc_set_mode(bus, slave->mode);
	if (flags & SPI_XFER_BEGIN) {
		spifc_chipselect(dev, 1);
		buf = (u8 *)dout;
		if (!buf || (len > 5)) {
			printf("%s: error command\n", __func__);
			ret = -EINVAL;
		}
		else {
			spifc_user_cmd(priv, buf[0], &buf[1], len - 1);
			/* save the command for next xfer dual/quad setting */
			priv->cmd = buf[0];
		}
	}
	else if (dout && priv->cmd) {
		buf = (u8 *)dout;
		spifc_set_tx_op_mode(priv, slave->mode, priv->cmd);
		while (len > 0) {
			lening = min_t(size_t, SPIFC_CACHE_SIZE_IN_BYTE, len);
			ret = spifc_user_cmd_dout(priv, buf, lening, flags);
			if (ret)
				break;
			buf += lening;
			len -= lening;
		}
	}
	else if (din && priv->cmd) {
		buf = (u8 *)din;
		spifc_set_rx_op_mode(priv, slave->mode, priv->cmd);
		while (len > 0) {
			lening = min_t(size_t, SPIFC_CACHE_SIZE_IN_BYTE, len);
			ret = spifc_user_cmd_din(priv, buf, lening, flags);
			if (ret)
				break;
			buf += lening;
			len -= lening;
		}
	}

	if (ret || flags & SPI_XFER_END) {
		spifc_chipselect(dev, 0);
		priv->cmd = 0;
	}

	return ret;
}

static int spifc_probe(struct udevice *bus)
{
	struct spifc_platdata *plat = dev_get_platdata(bus);
	struct spifc_priv *priv = dev_get_priv(bus);

	priv->regs = (struct spifc_regs *)plat->reg;
	if (plat->clk_get)
		priv->clk = plat->clk_get(bus, "spifc_clk");
	if (plat->pinctrl_get)
		priv->pinctrl = plat->pinctrl_get(bus, "spifc_pinctrl");
	spifc_cs_gpios_init(priv, plat);
	priv->speed = -1;
	priv->mode = -1;
	printf("%s: reg=%p, mem_map=%p\n", __func__,
			(void *)priv->regs, (void *)plat->mem_map);
	return 0;
}

#ifdef CONFIG_OF_CONTROL
static int spifc_ofdata_to_platdata(struct udevice *bus)
{
	spifc_dbg("step 1\n");
	struct spifc_platdata *plat = dev_get_platdata(bus);
	const void *blob = gd->fdt_blob;
	int node = bus->of_offset;

	plat->reg = fdtdec_get_addr(blob, node, "reg");
	plat->mem_map = fdtdec_get_addr(blob, node, "ahb");
	/* default 5MHz */

	return 0;
}

static const struct udevice_id spifc_ids[] = {
	{ .compatible = "amlogic, spifc" },
	{ }
};
#endif

static const struct dm_spi_ops spifc_ops = {
	.claim_bus = spifc_claim_bus,
	.release_bus = spifc_release_bus,
	.xfer = spifc_xfer,
	.set_speed = spifc_set_speed,
	.set_mode = spifc_set_mode,
	.set_wordlen = spifc_set_wordlen,
};

U_BOOT_DRIVER(spifc) = {
	.name = "spifc",
	.id = UCLASS_SPI,
#ifdef CONFIG_OF_CONTROL
	.of_match = spifc_ids,
	.ofdata_to_platdata = spifc_ofdata_to_platdata,
	.platdata_auto_alloc_size = sizeof(struct spifc_platdata),
#endif
	.priv_auto_alloc_size = sizeof(struct spifc_priv),
	.per_child_auto_alloc_size = sizeof(struct spi_slave),
	.ops= &spifc_ops,
	.probe = spifc_probe,
};