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Release 4.14 drivers/mmc/host/moxart-mmc.c

Directory: drivers/mmc/host
/*
 * MOXA ART MMC host driver.
 *
 * Copyright (C) 2014 Jonas Jensen
 *
 * Jonas Jensen <jonas.jensen@gmail.com>
 *
 * Based on code from
 * Moxa Technologies Co., Ltd. <www.moxa.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/blkdev.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/mmc/host.h>
#include <linux/mmc/sd.h>
#include <linux/sched.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/clk.h>
#include <linux/bitops.h>
#include <linux/of_dma.h>
#include <linux/spinlock.h>


#define REG_COMMAND		0

#define REG_ARGUMENT		4

#define REG_RESPONSE0		8

#define REG_RESPONSE1		12

#define REG_RESPONSE2		16

#define REG_RESPONSE3		20

#define REG_RESPONSE_COMMAND	24

#define REG_DATA_CONTROL	28

#define REG_DATA_TIMER		32

#define REG_DATA_LENGTH		36

#define REG_STATUS		40

#define REG_CLEAR		44

#define REG_INTERRUPT_MASK	48

#define REG_POWER_CONTROL	52

#define REG_CLOCK_CONTROL	56

#define REG_BUS_WIDTH		60

#define REG_DATA_WINDOW		64

#define REG_FEATURE		68

#define REG_REVISION		72

/* REG_COMMAND */

#define CMD_SDC_RESET		BIT(10)

#define CMD_EN			BIT(9)

#define CMD_APP_CMD		BIT(8)

#define CMD_LONG_RSP		BIT(7)

#define CMD_NEED_RSP		BIT(6)

#define CMD_IDX_MASK		0x3f

/* REG_RESPONSE_COMMAND */

#define RSP_CMD_APP		BIT(6)

#define RSP_CMD_IDX_MASK	0x3f

/* REG_DATA_CONTROL */

#define DCR_DATA_FIFO_RESET     BIT(8)

#define DCR_DATA_THRES          BIT(7)

#define DCR_DATA_EN		BIT(6)

#define DCR_DMA_EN		BIT(5)

#define DCR_DATA_WRITE		BIT(4)

#define DCR_BLK_SIZE		0x0f

/* REG_DATA_LENGTH */

#define DATA_LEN_MASK		0xffffff

/* REG_STATUS */

#define WRITE_PROT		BIT(12)

#define CARD_DETECT		BIT(11)
/* 1-10 below can be sent to either registers, interrupt or clear. */

#define CARD_CHANGE		BIT(10)

#define FIFO_ORUN		BIT(9)

#define FIFO_URUN		BIT(8)

#define DATA_END		BIT(7)

#define CMD_SENT		BIT(6)

#define DATA_CRC_OK		BIT(5)

#define RSP_CRC_OK		BIT(4)

#define DATA_TIMEOUT		BIT(3)

#define RSP_TIMEOUT		BIT(2)

#define DATA_CRC_FAIL		BIT(1)

#define RSP_CRC_FAIL		BIT(0)


#define MASK_RSP		(RSP_TIMEOUT | RSP_CRC_FAIL | \
                                 RSP_CRC_OK  | CARD_DETECT  | CMD_SENT)


#define MASK_DATA		(DATA_CRC_OK   | DATA_END | \
                                 DATA_CRC_FAIL | DATA_TIMEOUT)


#define MASK_INTR_PIO		(FIFO_URUN | FIFO_ORUN | CARD_CHANGE)

/* REG_POWER_CONTROL */

#define SD_POWER_ON		BIT(4)

#define SD_POWER_MASK		0x0f

/* REG_CLOCK_CONTROL */

#define CLK_HISPD		BIT(9)

#define CLK_OFF			BIT(8)

#define CLK_SD			BIT(7)

#define CLK_DIV_MASK		0x7f

/* REG_BUS_WIDTH */

#define BUS_WIDTH_8		BIT(2)

#define BUS_WIDTH_4		BIT(1)

#define BUS_WIDTH_1		BIT(0)


#define MMC_VDD_360		23

#define MIN_POWER		(MMC_VDD_360 - SD_POWER_MASK)

#define MAX_RETRIES		500000


struct moxart_host {
	
spinlock_t			lock;

	
void __iomem			*base;

	
phys_addr_t			reg_phys;

	
struct dma_chan			*dma_chan_tx;
	
struct dma_chan                 *dma_chan_rx;
	
struct dma_async_tx_descriptor	*tx_desc;
	
struct mmc_host			*mmc;
	
struct mmc_request		*mrq;
	
struct scatterlist		*cur_sg;
	
struct completion		dma_complete;
	
struct completion		pio_complete;

	
u32				num_sg;
	
u32				data_remain;
	
u32				data_len;
	
u32				fifo_width;
	
u32				timeout;
	
u32				rate;

	
long				sysclk;

	
bool				have_dma;
	
bool				is_removed;
};


static inline void moxart_init_sg(struct moxart_host *host, struct mmc_data *data) { host->cur_sg = data->sg; host->num_sg = data->sg_len; host->data_remain = host->cur_sg->length; if (host->data_remain > host->data_len) host->data_remain = host->data_len; }

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static inline int moxart_next_sg(struct moxart_host *host) { int remain; struct mmc_data *data = host->mrq->cmd->data; host->cur_sg++; host->num_sg--; if (host->num_sg > 0) { host->data_remain = host->cur_sg->length; remain = host->data_len - data->bytes_xfered; if (remain > 0 && remain < host->data_remain) host->data_remain = remain; } return host->num_sg; }

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static int moxart_wait_for_status(struct moxart_host *host, u32 mask, u32 *status) { int ret = -ETIMEDOUT; u32 i; for (i = 0; i < MAX_RETRIES; i++) { *status = readl(host->base + REG_STATUS); if (!(*status & mask)) { udelay(5); continue; } writel(*status & mask, host->base + REG_CLEAR); ret = 0; break; } if (ret) dev_err(mmc_dev(host->mmc), "timed out waiting for status\n"); return ret; }

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static void moxart_send_command(struct moxart_host *host, struct mmc_command *cmd) { u32 status, cmdctrl; writel(RSP_TIMEOUT | RSP_CRC_OK | RSP_CRC_FAIL | CMD_SENT, host->base + REG_CLEAR); writel(cmd->arg, host->base + REG_ARGUMENT); cmdctrl = cmd->opcode & CMD_IDX_MASK; if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND || cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS || cmdctrl == SD_APP_SEND_NUM_WR_BLKS) cmdctrl |= CMD_APP_CMD; if (cmd->flags & MMC_RSP_PRESENT) cmdctrl |= CMD_NEED_RSP; if (cmd->flags & MMC_RSP_136) cmdctrl |= CMD_LONG_RSP; writel(cmdctrl | CMD_EN, host->base + REG_COMMAND); if (moxart_wait_for_status(host, MASK_RSP, &status) == -ETIMEDOUT) cmd->error = -ETIMEDOUT; if (status & RSP_TIMEOUT) { cmd->error = -ETIMEDOUT; return; } if (status & RSP_CRC_FAIL) { cmd->error = -EIO; return; } if (status & RSP_CRC_OK) { if (cmd->flags & MMC_RSP_136) { cmd->resp[3] = readl(host->base + REG_RESPONSE0); cmd->resp[2] = readl(host->base + REG_RESPONSE1); cmd->resp[1] = readl(host->base + REG_RESPONSE2); cmd->resp[0] = readl(host->base + REG_RESPONSE3); } else { cmd->resp[0] = readl(host->base + REG_RESPONSE0); } } }

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static void moxart_dma_complete(void *param) { struct moxart_host *host = param; complete(&host->dma_complete); }

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static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host) { u32 len, dir_slave; long dma_time; struct dma_async_tx_descriptor *desc = NULL; struct dma_chan *dma_chan; if (host->data_len == data->bytes_xfered) return; if (data->flags & MMC_DATA_WRITE) { dma_chan = host->dma_chan_tx; dir_slave = DMA_MEM_TO_DEV; } else { dma_chan = host->dma_chan_rx; dir_slave = DMA_DEV_TO_MEM; } len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len, mmc_get_dma_dir(data)); if (len > 0) { desc = dmaengine_prep_slave_sg(dma_chan, data->sg, len, dir_slave, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); } else { dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n"); } if (desc) { host->tx_desc = desc; desc->callback = moxart_dma_complete; desc->callback_param = host; dmaengine_submit(desc); dma_async_issue_pending(dma_chan); } data->bytes_xfered += host->data_remain; dma_time = wait_for_completion_interruptible_timeout( &host->dma_complete, host->timeout); dma_unmap_sg(dma_chan->device->dev, data->sg, data->sg_len, mmc_get_dma_dir(data)); }

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static void moxart_transfer_pio(struct moxart_host *host) { struct mmc_data *data = host->mrq->cmd->data; u32 *sgp, len = 0, remain, status; if (host->data_len == data->bytes_xfered) return; sgp = sg_virt(host->cur_sg); remain = host->data_remain; if (data->flags & MMC_DATA_WRITE) { while (remain > 0) { if (moxart_wait_for_status(host, FIFO_URUN, &status) == -ETIMEDOUT) { data->error = -ETIMEDOUT; complete(&host->pio_complete); return; } for (len = 0; len < remain && len < host->fifo_width;) { iowrite32(*sgp, host->base + REG_DATA_WINDOW); sgp++; len += 4; } remain -= len; } } else { while (remain > 0) { if (moxart_wait_for_status(host, FIFO_ORUN, &status) == -ETIMEDOUT) { data->error = -ETIMEDOUT; complete(&host->pio_complete); return; } for (len = 0; len < remain && len < host->fifo_width;) { /* SCR data must be read in big endian. */ if (data->mrq->cmd->opcode == SD_APP_SEND_SCR) *sgp = ioread32be(host->base + REG_DATA_WINDOW); else *sgp = ioread32(host->base + REG_DATA_WINDOW); sgp++; len += 4; } remain -= len; } } data->bytes_xfered += host->data_remain - remain; host->data_remain = remain; if (host->data_len != data->bytes_xfered) moxart_next_sg(host); else complete(&host->pio_complete); }

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static void moxart_prepare_data(struct moxart_host *host) { struct mmc_data *data = host->mrq->cmd->data; u32 datactrl; int blksz_bits; if (!data) return; host->data_len = data->blocks * data->blksz; blksz_bits = ffs(data->blksz) - 1; BUG_ON(1 << blksz_bits != data->blksz); moxart_init_sg(host, data); datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE); if (data->flags & MMC_DATA_WRITE) datactrl |= DCR_DATA_WRITE; if ((host->data_len > host->fifo_width) && host->have_dma) datactrl |= DCR_DMA_EN; writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL); writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR); writel(host->rate, host->base + REG_DATA_TIMER); writel(host->data_len, host->base + REG_DATA_LENGTH); writel(datactrl, host->base + REG_DATA_CONTROL); }

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static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq) { struct moxart_host *host = mmc_priv(mmc); long pio_time; unsigned long flags; u32 status; spin_lock_irqsave(&host->lock, flags); init_completion(&host->dma_complete); init_completion(&host->pio_complete); host->mrq = mrq; if (readl(host->base + REG_STATUS) & CARD_DETECT) { mrq->cmd->error = -ETIMEDOUT; goto request_done; } moxart_prepare_data(host); moxart_send_command(host, host->mrq->cmd); if (mrq->cmd->data) { if ((host->data_len > host->fifo_width) && host->have_dma) { writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK); spin_unlock_irqrestore(&host->lock, flags); moxart_transfer_dma(mrq->cmd->data, host); spin_lock_irqsave(&host->lock, flags); } else { writel(MASK_INTR_PIO, host->base + REG_INTERRUPT_MASK); spin_unlock_irqrestore(&host->lock, flags); /* PIO transfers start from interrupt. */ pio_time = wait_for_completion_interruptible_timeout( &host->pio_complete, host->timeout); spin_lock_irqsave(&host->lock, flags); } if (host->is_removed) { dev_err(mmc_dev(host->mmc), "card removed\n"); mrq->cmd->error = -ETIMEDOUT; goto request_done; } if (moxart_wait_for_status(host, MASK_DATA, &status) == -ETIMEDOUT) { mrq->cmd->data->error = -ETIMEDOUT; goto request_done; } if (status & DATA_CRC_FAIL) mrq->cmd->data->error = -ETIMEDOUT; if (mrq->cmd->data->stop) moxart_send_command(host, mrq->cmd->data->stop); } request_done: spin_unlock_irqrestore(&host->lock, flags); mmc_request_done(host->mmc, mrq); }

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static irqreturn_t moxart_irq(int irq, void *devid) { struct moxart_host *host = (struct moxart_host *)devid; u32 status; unsigned long flags; spin_lock_irqsave(&host->lock, flags); status = readl(host->base + REG_STATUS); if (status & CARD_CHANGE) { host->is_removed = status & CARD_DETECT; if (host->is_removed && host->have_dma) { dmaengine_terminate_all(host->dma_chan_tx); dmaengine_terminate_all(host->dma_chan_rx); } host->mrq = NULL; writel(MASK_INTR_PIO, host->base + REG_CLEAR); writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK); mmc_detect_change(host->mmc, 0); } if (status & (FIFO_ORUN | FIFO_URUN) && host->mrq) moxart_transfer_pio(host); spin_unlock_irqrestore(&host->lock, flags); return IRQ_HANDLED; }

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static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) { struct moxart_host *host = mmc_priv(mmc); unsigned long flags; u8 power, div; u32 ctrl; spin_lock_irqsave(&host->lock, flags); if (ios->clock) { for (div = 0; div < CLK_DIV_MASK; ++div) { if (ios->clock >= host->sysclk / (2 * (div + 1))) break; } ctrl = CLK_SD | div; host->rate = host->sysclk / (2 * (div + 1)); if (host->rate > host->sysclk) ctrl |= CLK_HISPD; writel(ctrl, host->base + REG_CLOCK_CONTROL); } if (ios->power_mode == MMC_POWER_OFF) { writel(readl(host->base + REG_POWER_CONTROL) & ~SD_POWER_ON, host->base + REG_POWER_CONTROL); } else { if (ios->vdd < MIN_POWER) power = 0; else power = ios->vdd - MIN_POWER; writel(SD_POWER_ON | (u32) power, host->base + REG_POWER_CONTROL); } switch (ios->bus_width) { case MMC_BUS_WIDTH_4: writel(BUS_WIDTH_4, host->base + REG_BUS_WIDTH); break; case MMC_BUS_WIDTH_8: writel(BUS_WIDTH_8, host->base + REG_BUS_WIDTH); break; default: writel(BUS_WIDTH_1, host->base + REG_BUS_WIDTH); break; } spin_unlock_irqrestore(&host->lock, flags); }

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static int moxart_get_ro(struct mmc_host *mmc) { struct moxart_host *host = mmc_priv(mmc); return !!(readl(host->base + REG_STATUS) & WRITE_PROT); }

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static const struct mmc_host_ops moxart_ops = { .request = moxart_request, .set_ios = moxart_set_ios, .get_ro = moxart_get_ro, };
static int moxart_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *node = dev->of_node; struct resource res_mmc; struct mmc_host *mmc; struct moxart_host *host = NULL; struct dma_slave_config cfg; struct clk *clk; void __iomem *reg_mmc; int irq, ret; u32 i; mmc = mmc_alloc_host(sizeof(struct moxart_host), dev); if (!mmc) { dev_err(dev, "mmc_alloc_host failed\n"); ret = -ENOMEM; goto out; } ret = of_address_to_resource(node, 0, &res_mmc); if (ret) { dev_err(dev, "of_address_to_resource failed\n"); goto out; } irq = irq_of_parse_and_map(node, 0); if (irq <= 0) { dev_err(dev, "irq_of_parse_and_map failed\n"); ret = -EINVAL; goto out; } clk = devm_clk_get(dev, NULL); if (IS_ERR(clk)) { ret = PTR_ERR(clk); goto out; } reg_mmc = devm_ioremap_resource(dev, &res_mmc); if (IS_ERR(reg_mmc)) { ret = PTR_ERR(reg_mmc); goto out; } ret = mmc_of_parse(mmc); if (ret) goto out; host = mmc_priv(mmc); host->mmc = mmc; host->base = reg_mmc; host->reg_phys = res_mmc.start; host->timeout = msecs_to_jiffies(1000); host->sysclk = clk_get_rate(clk); host->fifo_width = readl(host->base + REG_FEATURE) << 2; host->dma_chan_tx = dma_request_slave_channel_reason(dev, "tx"); host->dma_chan_rx = dma_request_slave_channel_reason(dev, "rx"); spin_lock_init(&host->lock); mmc->ops = &moxart_ops; mmc->f_max = DIV_ROUND_CLOSEST(host->sysclk, 2); mmc->f_min = DIV_ROUND_CLOSEST(host->sysclk, CLK_DIV_MASK * 2); mmc->ocr_avail = 0xffff00; /* Support 2.0v - 3.6v power. */ if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) { if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER || PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) { ret = -EPROBE_DEFER; goto out; } dev_dbg(dev, "PIO mode transfer enabled\n"); host->have_dma = false; } else { dev_dbg(dev, "DMA channels found (%p,%p)\n", host->dma_chan_tx, host->dma_chan_rx); host->have_dma = true; cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; cfg.direction = DMA_MEM_TO_DEV; cfg.src_addr = 0; cfg.dst_addr = host->reg_phys + REG_DATA_WINDOW; dmaengine_slave_config(host->dma_chan_tx, &cfg); cfg.direction = DMA_DEV_TO_MEM; cfg.src_addr = host->reg_phys + REG_DATA_WINDOW; cfg.dst_addr = 0; dmaengine_slave_config(host->dma_chan_rx, &cfg); } switch ((readl(host->base + REG_BUS_WIDTH) >> 3) & 3) { case 1: mmc->caps |= MMC_CAP_4_BIT_DATA; break; case 2: mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA; break; default: break; } writel(0, host->base + REG_INTERRUPT_MASK); writel(CMD_SDC_RESET, host->base + REG_COMMAND); for (i = 0; i < MAX_RETRIES; i++) { if (!(readl(host->base + REG_COMMAND) & CMD_SDC_RESET)) break; udelay(5); } ret = devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host); if (ret) goto out; dev_set_drvdata(dev, mmc); mmc_add_host(mmc); dev_dbg(dev, "IRQ=%d, FIFO is %d bytes\n", irq, host->fifo_width); return 0; out: if (mmc) mmc_free_host(mmc); return ret; }

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static int moxart_remove(struct platform_device *pdev) { struct mmc_host *mmc = dev_get_drvdata(&pdev->dev); struct moxart_host *host = mmc_priv(mmc); dev_set_drvdata(&pdev->dev, NULL); if (mmc) { if (!IS_ERR(host->dma_chan_tx)) dma_release_channel(host->dma_chan_tx); if (!IS_ERR(host->dma_chan_rx)) dma_release_channel(host->dma_chan_rx); mmc_remove_host(mmc); mmc_free_host(mmc); writel(0, host->base + REG_INTERRUPT_MASK); writel(0, host->base + REG_POWER_CONTROL); writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF, host->base + REG_CLOCK_CONTROL); } return 0; }

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static const struct of_device_id moxart_mmc_match[] = { { .compatible = "moxa,moxart-mmc" }, { .compatible = "faraday,ftsdc010" }, { } }; MODULE_DEVICE_TABLE(of, moxart_mmc_match); static struct platform_driver moxart_mmc_driver = { .probe = moxart_probe, .remove = moxart_remove, .driver = { .name = "mmc-moxart", .of_match_table = moxart_mmc_match, }, }; module_platform_driver(moxart_mmc_driver); MODULE_ALIAS("platform:mmc-moxart"); MODULE_DESCRIPTION("MOXA ART MMC driver"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");

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Luis de Bethencourt70.20%114.29%
Nicholas Mc Guire30.09%114.29%
Julia Lawall10.03%114.29%
Total3449100.00%7100.00%
Directory: drivers/mmc/host
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