path: root/drivers/mmc/host/jz4740_mmc.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
 *  Copyright (C) 2013, Imagination Technologies
 *
 *  JZ4740 SD/MMC controller driver
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/mmc/host.h>
#include <linux/mmc/slot-gpio.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>

#include <asm/cacheflush.h>

#define JZ_REG_MMC_STRPCL	0x00
#define JZ_REG_MMC_STATUS	0x04
#define JZ_REG_MMC_CLKRT	0x08
#define JZ_REG_MMC_CMDAT	0x0C
#define JZ_REG_MMC_RESTO	0x10
#define JZ_REG_MMC_RDTO		0x14
#define JZ_REG_MMC_BLKLEN	0x18
#define JZ_REG_MMC_NOB		0x1C
#define JZ_REG_MMC_SNOB		0x20
#define JZ_REG_MMC_IMASK	0x24
#define JZ_REG_MMC_IREG		0x28
#define JZ_REG_MMC_CMD		0x2C
#define JZ_REG_MMC_ARG		0x30
#define JZ_REG_MMC_RESP_FIFO	0x34
#define JZ_REG_MMC_RXFIFO	0x38
#define JZ_REG_MMC_TXFIFO	0x3C
#define JZ_REG_MMC_LPM		0x40
#define JZ_REG_MMC_DMAC		0x44

#define JZ_MMC_STRPCL_EXIT_MULTIPLE BIT(7)
#define JZ_MMC_STRPCL_EXIT_TRANSFER BIT(6)
#define JZ_MMC_STRPCL_START_READWAIT BIT(5)
#define JZ_MMC_STRPCL_STOP_READWAIT BIT(4)
#define JZ_MMC_STRPCL_RESET BIT(3)
#define JZ_MMC_STRPCL_START_OP BIT(2)
#define JZ_MMC_STRPCL_CLOCK_CONTROL (BIT(1) | BIT(0))
#define JZ_MMC_STRPCL_CLOCK_STOP BIT(0)
#define JZ_MMC_STRPCL_CLOCK_START BIT(1)


#define JZ_MMC_STATUS_IS_RESETTING BIT(15)
#define JZ_MMC_STATUS_SDIO_INT_ACTIVE BIT(14)
#define JZ_MMC_STATUS_PRG_DONE BIT(13)
#define JZ_MMC_STATUS_DATA_TRAN_DONE BIT(12)
#define JZ_MMC_STATUS_END_CMD_RES BIT(11)
#define JZ_MMC_STATUS_DATA_FIFO_AFULL BIT(10)
#define JZ_MMC_STATUS_IS_READWAIT BIT(9)
#define JZ_MMC_STATUS_CLK_EN BIT(8)
#define JZ_MMC_STATUS_DATA_FIFO_FULL BIT(7)
#define JZ_MMC_STATUS_DATA_FIFO_EMPTY BIT(6)
#define JZ_MMC_STATUS_CRC_RES_ERR BIT(5)
#define JZ_MMC_STATUS_CRC_READ_ERROR BIT(4)
#define JZ_MMC_STATUS_TIMEOUT_WRITE BIT(3)
#define JZ_MMC_STATUS_CRC_WRITE_ERROR BIT(2)
#define JZ_MMC_STATUS_TIMEOUT_RES BIT(1)
#define JZ_MMC_STATUS_TIMEOUT_READ BIT(0)

#define JZ_MMC_STATUS_READ_ERROR_MASK (BIT(4) | BIT(0))
#define JZ_MMC_STATUS_WRITE_ERROR_MASK (BIT(3) | BIT(2))


#define JZ_MMC_CMDAT_IO_ABORT BIT(11)
#define JZ_MMC_CMDAT_BUS_WIDTH_4BIT BIT(10)
#define JZ_MMC_CMDAT_BUS_WIDTH_8BIT (BIT(10) | BIT(9))
#define	JZ_MMC_CMDAT_BUS_WIDTH_MASK (BIT(10) | BIT(9))
#define JZ_MMC_CMDAT_DMA_EN BIT(8)
#define JZ_MMC_CMDAT_INIT BIT(7)
#define JZ_MMC_CMDAT_BUSY BIT(6)
#define JZ_MMC_CMDAT_STREAM BIT(5)
#define JZ_MMC_CMDAT_WRITE BIT(4)
#define JZ_MMC_CMDAT_DATA_EN BIT(3)
#define JZ_MMC_CMDAT_RESPONSE_FORMAT (BIT(2) | BIT(1) | BIT(0))
#define JZ_MMC_CMDAT_RSP_R1 1
#define JZ_MMC_CMDAT_RSP_R2 2
#define JZ_MMC_CMDAT_RSP_R3 3

#define JZ_MMC_IRQ_SDIO BIT(7)
#define JZ_MMC_IRQ_TXFIFO_WR_REQ BIT(6)
#define JZ_MMC_IRQ_RXFIFO_RD_REQ BIT(5)
#define JZ_MMC_IRQ_END_CMD_RES BIT(2)
#define JZ_MMC_IRQ_PRG_DONE BIT(1)
#define JZ_MMC_IRQ_DATA_TRAN_DONE BIT(0)

#define JZ_MMC_DMAC_DMA_SEL BIT(1)
#define JZ_MMC_DMAC_DMA_EN BIT(0)

#define	JZ_MMC_LPM_DRV_RISING BIT(31)
#define	JZ_MMC_LPM_DRV_RISING_QTR_PHASE_DLY BIT(31)
#define	JZ_MMC_LPM_DRV_RISING_1NS_DLY BIT(30)
#define	JZ_MMC_LPM_SMP_RISING_QTR_OR_HALF_PHASE_DLY BIT(29)
#define	JZ_MMC_LPM_LOW_POWER_MODE_EN BIT(0)

#define JZ_MMC_CLK_RATE 24000000
#define JZ_MMC_REQ_TIMEOUT_MS 5000

enum jz4740_mmc_version {
	JZ_MMC_JZ4740,
	JZ_MMC_JZ4725B,
	JZ_MMC_JZ4760,
	JZ_MMC_JZ4780,
	JZ_MMC_X1000,
};

enum jz4740_mmc_state {
	JZ4740_MMC_STATE_READ_RESPONSE,
	JZ4740_MMC_STATE_TRANSFER_DATA,
	JZ4740_MMC_STATE_SEND_STOP,
	JZ4740_MMC_STATE_DONE,
};

/*
 * The MMC core allows to prepare a mmc_request while another mmc_request
 * is in-flight. This is used via the pre_req/post_req hooks.
 * This driver uses the pre_req/post_req hooks to map/unmap the mmc_request.
 * Following what other drivers do (sdhci, dw_mmc) we use the following cookie
 * flags to keep track of the mmc_request mapping state.
 *
 * COOKIE_UNMAPPED: the request is not mapped.
 * COOKIE_PREMAPPED: the request was mapped in pre_req,
 * and should be unmapped in post_req.
 * COOKIE_MAPPED: the request was mapped in the irq handler,
 * and should be unmapped before mmc_request_done is called..
 */
enum jz4780_cookie {
	COOKIE_UNMAPPED = 0,
	COOKIE_PREMAPPED,
	COOKIE_MAPPED,
};

struct jz4740_mmc_host {
	struct mmc_host *mmc;
	struct platform_device *pdev;
	struct clk *clk;

	enum jz4740_mmc_version version;

	int irq;

	void __iomem *base;
	struct resource *mem_res;
	struct mmc_request *req;
	struct mmc_command *cmd;

	unsigned long waiting;

	uint32_t cmdat;

	uint32_t irq_mask;

	spinlock_t lock;

	struct timer_list timeout_timer;
	struct sg_mapping_iter miter;
	enum jz4740_mmc_state state;

	/* DMA support */
	struct dma_chan *dma_rx;
	struct dma_chan *dma_tx;
	bool use_dma;

/* The DMA trigger level is 8 words, that is to say, the DMA read
 * trigger is when data words in MSC_RXFIFO is >= 8 and the DMA write
 * trigger is when data words in MSC_TXFIFO is < 8.
 */
#define JZ4740_MMC_FIFO_HALF_SIZE 8
};

static void jz4740_mmc_write_irq_mask(struct jz4740_mmc_host *host,
				      uint32_t val)
{
	if (host->version >= JZ_MMC_JZ4725B)
		return writel(val, host->base + JZ_REG_MMC_IMASK);
	else
		return writew(val, host->base + JZ_REG_MMC_IMASK);
}

static void jz4740_mmc_write_irq_reg(struct jz4740_mmc_host *host,
				     uint32_t val)
{
	if (host->version >= JZ_MMC_JZ4780)
		writel(val, host->base + JZ_REG_MMC_IREG);
	else
		writew(val, host->base + JZ_REG_MMC_IREG);
}

static uint32_t jz4740_mmc_read_irq_reg(struct jz4740_mmc_host *host)
{
	if (host->version >= JZ_MMC_JZ4780)
		return readl(host->base + JZ_REG_MMC_IREG);
	else
		return readw(host->base + JZ_REG_MMC_IREG);
}

/*----------------------------------------------------------------------------*/
/* DMA infrastructure */

static void jz4740_mmc_release_dma_channels(struct jz4740_mmc_host *host)
{
	if (!host