path: root/drivers/memory/renesas-rpc-if.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Renesas RPC-IF core driver
 *
 * Copyright (C) 2018-2019 Renesas Solutions Corp.
 * Copyright (C) 2019 Macronix International Co., Ltd.
 * Copyright (C) 2019-2020 Cogent Embedded, Inc.
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include <linux/reset.h>

#include <memory/renesas-rpc-if.h>

#include "renesas-rpc-if-regs.h"
#include "renesas-xspi-if-regs.h"

static const struct regmap_range rpcif_volatile_ranges[] = {
	regmap_reg_range(RPCIF_SMRDR0, RPCIF_SMRDR1),
	regmap_reg_range(RPCIF_SMWDR0, RPCIF_SMWDR1),
	regmap_reg_range(RPCIF_CMNSR, RPCIF_CMNSR),
};

static const struct regmap_access_table rpcif_volatile_table = {
	.yes_ranges	= rpcif_volatile_ranges,
	.n_yes_ranges	= ARRAY_SIZE(rpcif_volatile_ranges),
};

static const struct regmap_range xspi_volatile_ranges[] = {
	regmap_reg_range(XSPI_CDD0BUF0, XSPI_CDD0BUF0),
};

static const struct regmap_access_table xspi_volatile_table = {
	.yes_ranges	= xspi_volatile_ranges,
	.n_yes_ranges	= ARRAY_SIZE(xspi_volatile_ranges),
};

struct rpcif_priv;

struct rpcif_impl {
	int (*hw_init)(struct rpcif_priv *rpc, bool hyperflash);
	void (*prepare)(struct rpcif_priv *rpc, const struct rpcif_op *op,
			u64 *offs, size_t *len);
	int (*manual_xfer)(struct rpcif_priv *rpc);
	size_t (*dirmap_read)(struct rpcif_priv *rpc, u64 offs, size_t len,
			      void *buf);
	u32 status_reg;
	u32 status_mask;
};

struct rpcif_info {
	const struct regmap_config *regmap_config;
	const struct rpcif_impl *impl;
	enum rpcif_type type;
	u8 strtim;
};

struct rpcif_priv {
	struct device *dev;
	void __iomem *base;
	void __iomem *dirmap;
	struct regmap *regmap;
	struct reset_control *rstc;
	struct platform_device *vdev;
	size_t size;
	const struct rpcif_info *info;
	enum rpcif_data_dir dir;
	u8 bus_size;
	u8 xfer_size;
	u8 addr_nbytes;		/* Specified for xSPI */
	u32 proto;		/* Specified for xSPI */
	void *buffer;
	u32 xferlen;
	u32 smcr;
	u32 smadr;
	u32 command;		/* DRCMR or SMCMR */
	u32 option;		/* DROPR or SMOPR */
	u32 enable;		/* DRENR or SMENR */
	u32 dummy;		/* DRDMCR or SMDMCR */
	u32 ddr;		/* DRDRENR or SMDRENR */
};

/*
 * Custom accessor functions to ensure SM[RW]DR[01] are always accessed with
 * proper width.  Requires rpcif_priv.xfer_size to be correctly set before!
 */
static int rpcif_reg_read(void *context, unsigned int reg, unsigned int *val)
{
	struct rpcif_priv *rpc = context;

	switch (reg) {
	case RPCIF_SMRDR0:
	case RPCIF_SMWDR0:
		switch (rpc->xfer_size) {
		case 1:
			*val = readb(rpc->base + reg);
			return 0;

		case 2:
			*val = readw(rpc->base + reg);
			return 0;

		case 4:
		case