/* * Atmel MultiMedia Card Interface driver * * Copyright (C) 2004-2008 Atmel Corporation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "atmel-mci-regs.h" #define ATMCI_DATA_ERROR_FLAGS (MCI_DCRCE | MCI_DTOE | MCI_OVRE | MCI_UNRE) #define ATMCI_DMA_THRESHOLD 16 enum { EVENT_CMD_COMPLETE = 0, EVENT_XFER_COMPLETE, EVENT_DATA_COMPLETE, EVENT_DATA_ERROR, }; enum atmel_mci_state { STATE_IDLE = 0, STATE_SENDING_CMD, STATE_SENDING_DATA, STATE_DATA_BUSY, STATE_SENDING_STOP, STATE_DATA_ERROR, }; struct atmel_mci_dma { #ifdef CONFIG_MMC_ATMELMCI_DMA struct dma_chan *chan; struct dma_async_tx_descriptor *data_desc; #endif }; /** * struct atmel_mci - MMC controller state shared between all slots * @lock: Spinlock protecting the queue and associated data. * @regs: Pointer to MMIO registers. * @sg: Scatterlist entry currently being processed by PIO code, if any. * @pio_offset: Offset into the current scatterlist entry. * @cur_slot: The slot which is currently using the controller. * @mrq: The request currently being processed on @cur_slot, * or NULL if the controller is idle. * @cmd: The command currently being sent to the card, or NULL. * @data: The data currently being transferred, or NULL if no data * transfer is in progress. * @dma: DMA client state. * @data_chan: DMA channel being used for the current data transfer. * @cmd_status: Snapshot of SR taken upon completion of the current * command. Only valid when EVENT_CMD_COMPLETE is pending. * @data_status: Snapshot of SR taken upon completion of the current * data transfer. Only valid when EVENT_DATA_COMPLETE or * EVENT_DATA_ERROR is pending. * @stop_cmdr: Value to be loaded into CMDR when the stop command is * to be sent. * @tasklet: Tasklet running the request state machine. * @pending_events: Bitmask of events flagged by the interrupt handler * to be processed by the tasklet. * @completed_events: Bitmask of events which the state machine has * processed. * @state: Tasklet state. * @queue: List of slots waiting for access to the controller. * @need_clock_update: Update the clock rate before the next request. * @need_reset: Reset controller before next request. * @mode_reg: Value of the MR register. * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus * rate and timeout calculations. * @mapbase: Physical address of the MMIO registers. * @mck: The peripheral bus clock hooked up to the MMC controller. * @pdev: Platform device associated with the MMC controller. * @slot: Slots sharing this MMC controller. * * Locking * ======= * * @lock is a softirq-safe spinlock protecting @queue as well as * @cur_slot, @mrq and @state. These must always be updated * at the same time while holding @lock. * * @lock also protects mode_reg and need_clock_update since these are * used to synchronize mode register updates with the queue * processing. * * The @mrq field of struct atmel_mci_slot is also protected by @lock, * and must always be written at the same time as the slot is added to * @queue. * * @pending_events and @completed_events are accessed using atomic bit * operations, so they don't need any locking. * * None of the fields touched by the interrupt handler need any * locking. However, ordering is important: Before EVENT_DATA_ERROR or * EVENT_DATA_COMPLETE is set in @pending_events, all data-related * interrupts must be disabled and @data_status updated with a * snapshot of SR. Similarly, before EVENT_CMD_COMPLETE is set, the * CMDRDY interupt must be disabled and @cmd_status updated with a * snapshot of SR, and before EVENT_XFER_COMPLETE can be set, the * bytes_xfered field of @data must be written. This is ensured by * using barriers. */ struct atmel_mci { spinlock_t lock; void __iomem *regs; struct scatterlist *sg; unsigned int pio_offset; struct atmel_mci_slot *cur_slot; struct mmc_request *mrq; struct mmc_command *cmd; struct mmc_data *data; struct atmel_mci_dma dma; struct dma_chan *data_chan; u32 cmd_status; u32 data_status; u32 stop_cmdr; struct tasklet_struct tasklet; unsigned long pending_events; unsigned long completed_events; enum atmel_mci_state state; struct list_head queue; bool need_clock_update; bool need_reset; u32 mode_reg; unsigned long bus_hz; unsigned long mapbase; struct clk *mck; struct platform_device *pdev; struct atmel_mci_slot *slot[ATMEL_MCI_MAX_NR_SLOTS]; }; /** * struct atmel_mci_slot - MMC slot state * @mmc: The mmc_host representing this slot. * @host: The MMC controller this slot is using. * @sdc_reg: Value of SDCR to be written before using this slot. * @mrq: mmc_request currently being processed or waiting to be * processed, or NULL when the slot is idle. * @queue_node: List node for placing this node in the @queue list of * &struct atmel_mci. * @clock: Clock rate configured by set_ios(). Protected by host->lock. * @flags: Random state bits associated with the slot. * @detect_pin: GPIO pin used for card detection, or negative if not * available. * @wp_pin: GPIO pin used for card write protect sending, or negative * if not available. * @detect_is_active_high: The state of the detect pin when it is active. * @detect_timer: Timer used for debouncing @detect_pin interrupts. */ struct atmel_mci_slot { struct mmc_host *mmc; struct atmel_mci *host; u32 sdc_reg; struct mmc_request *mrq; struct list_head queue_node; unsigned int clock; unsigned long flags; #define ATMCI_CARD_PRESENT 0 #define ATMCI_CARD_NEED_INIT 1 #define ATMCI_SHUTDOWN 2 int detect_pin; int wp_pin; bool detect_is_active_high; struct timer_list detect_timer; }; #define atmci_test_and_clear_pending(host, event) \ test_and_clear_bit(event, &host->pending_events) #define atmci_set_completed(host, event) \ set_bit(event, &host->completed_events) #define atmci_set_pending(host, event) \ set_bit(event, &host->pending_events) /* * Enable or disable features/registers based on * whether the processor supports them */ static bool mci_has_rwproof(void) { if (cpu_is_at91sam9261() || cpu_is_at91rm9200()) return false; else return true; } /* * The debugfs stuff below is mostly optimized away when * CONFIG_DEBUG_FS is not set. */ static int atmci_req_show(struct seq_file *s, void *v) { struct atmel_mci_slot *slot = s->private; struct mmc_request *mrq; struct mmc_command *cmd; struct mmc_command *stop; struct mmc_data *data; /* Make sure we get a consistent snapshot */ spin_lock_bh(&slot->host->lock); mrq = slot->mrq; if (mrq) { cmd = mrq->cmd; data = mrq->data; stop = mrq->stop; if (cmd) seq_printf(s, "CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n", cmd->opcode, cmd->arg, cmd->flags, cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[2], cmd->error); if (data) seq_printf(s, "DATA %u / %u * %u flg %x err %d\n", data->bytes_xfered, data->blocks, data->blksz, data->flags, data->error); if (stop) seq_printf(s, "CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n", stop->opcode, stop->arg, stop->flags, stop->resp[0], stop->resp[1], stop->resp[2], stop->resp[2], stop->error); } spin_unlock_bh(&slot->host->lock); return 0; } static int atmci_req_open(struct inode *inode, struct file *file) { return single_open(file, atmci_req_show, inode->i_private); } static const struct file_operations atmci_req_fops = { .owner = THIS_MODULE, .open = atmci_req_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static void atmci_show_status_reg(struct seq_file *s, const char *regname, u32 value) { static const char *sr_bit[] = { [0] = "CMDRDY", [1] = "RXRDY", [2] = "TXRDY", [3] = "BLKE", [4] = "DTIP", [5] = "NOTBUSY", [6] = "ENDRX", [7] = "ENDTX", [8] = "SDIOIRQA", [9] = "SDIOIRQB", [12] = "SDIOWAIT", [14] = "RXBUFF", [15] = "TXBUFE", [16] = "RINDE", [17] = "RDIRE", [18] = "RCRCE", [19] = "RENDE", [20] = "RTOE", [21] = "DCRCE", [22] = "DTOE", [23] = "CSTOE", [24] = "BLKOVRE", [25] = "DMADONE", [26] = "FIFOEMPTY", [27] = "XFRDONE", [30] = "OVRE", [31] = "UNRE", }; unsigned int i; seq_printf(s, "%s:\t0x%08x", regname, value); for (i = 0; i < ARRAY_SIZE(sr_bit); i++) { if (value & (1 << i)) { if (sr_bit[i]) seq_printf(s, " %s", sr_bit[i]); else seq_puts(s, " UNKNOWN"); } } seq_putc(s, '\n'); } static int atmci_regs_show(struct seq_file *s, void *v) { struct atmel_mci *host = s->private; u32 *buf; buf = kmalloc(MCI_REGS_SIZE, GFP_KERNEL); if (!buf) return -ENOMEM; /* * Grab a more or less consistent snapshot. Note that we're * not disabling interrupts, so IMR and SR may not be * consistent. */ spin_lock_bh(&host->lock); clk_enable(host->mck); memcpy_fromio(buf, host->regs, MCI_REGS_SIZE); clk_disable(host->mck); spin_unlock_bh(&host->lock); seq_printf(s, "MR:\t0x%08x%s%s CLKDIV=%u\n", buf[MCI_MR / 4], buf[MCI_MR / 4] & MCI_MR_RDPROOF ? " RDPROOF" : "", buf[MCI_MR / 4] & MCI_MR_WRPROOF ? " WRPROOF" : "", buf[MCI_MR / 4] & 0xff); seq_printf(s, "DTOR:\t0x%08x\n", buf[MCI_DTOR / 4]); seq_printf(s, "SDCR:\t0x%08x\n", buf[MCI_SDCR / 4]); seq_printf(s, "ARGR:\t0x%08x\n", buf[MCI_ARGR / 4]); seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n", buf[MCI_BLKR / 4], buf[MCI_BLKR / 4] & 0xffff, (buf[MCI_BLKR / 4] >> 16) & 0xffff); /* Don't read RSPR and RDR; it will consume the data there */ atmci_show_status_reg(s, "SR", buf[MCI_SR / 4]); atmci_show_status_reg(s, "IMR", buf[MCI_IMR / 4]); kfree(buf); return 0; } static int atmci_regs_open(struct inode *inode, struct file *file) { return single_open(file, atmci_regs_show, inode->i_private); } static const struct file_operations atmci_regs_fops = { .owner = THIS_MODULE, .open = atmci_regs_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static void atmci_init_debugfs(struct atmel_mci_slot *slot) { struct mmc_host *mmc = slot->mmc; struct atmel_mci *host = slot->host; struct dentry *root; struct dentry *node; root = mmc->debugfs_root; if (!root) return; node = debugfs_create_file("regs", S_IRUSR, root, host, &atmci_regs_fops); if (IS_ERR(node)) return; if (!node) goto err; node = debugfs_create_file("req", S_IRUSR, root, slot, &atmci_req_fops); if (!node) goto err; node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state); if (!node) goto err; node = debugfs_create_x32("pending_events", S_IRUSR, root, (u32 *)&host->pending_events); if (!node) goto err; node = debugfs_create_x32("completed_events", S_IRUSR, root, (u32 *)&host->completed_events); if (!node) goto err; return; err: dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n"); } static inline unsigned int ns_to_clocks(struct atmel_mci *host, unsigned int ns) { return (ns * (host->bus_hz / 1000000) + 999) / 1000; } static void atmci_set_timeout(struct atmel_mci *host, struct atmel_mci_slot *slot, struct mmc_data *data) { static unsigned dtomul_to_shift[] = { 0, 4, 7, 8, 10, 12, 16, 20 }; unsigned timeout; unsigned dtocyc; unsigned dtomul; timeout = ns_to_clocks(host, data->timeout_ns) + data->timeout_clks; for (dtomul = 0; dtomul < 8; dtomul++) { unsigned shift = dtomul_to_shift[dtomul]; dtocyc = (timeout + (1 << shift) - 1) >> shift; if (dtocyc < 15) break; } if (dtomul >= 8) { dtomul = 7; dtocyc = 15; } dev_vdbg(&slot->mmc->class_dev, "setting timeout to %u cycles\n", dtocyc << dtomul_to_shift[dtomul]); mci_writel(host, DTOR, (MCI_DTOMUL(dtomul) | MCI_DTOCYC(dtocyc))); } /* * Return mask with command flags to be enabled for this command. */ static u32 atmci_prepare_command(struct mmc_host *mmc, struct mmc_command *cmd) { struct mmc_data *data; u32 cmdr; cmd->error = -EINPROGRESS; cmdr = MCI_CMDR_CMDNB(cmd->opcode); if (cmd->flags & MMC_RSP_PRESENT) { if (cmd->flags & MMC_RSP_136) cmdr |= MCI_CMDR_RSPTYP_136BIT; else cmdr |= MCI_CMDR_RSPTYP_48BIT; } /* * This should really be MAXLAT_5 for CMD2 and ACMD41, but * it's too difficult to determine whether this is an ACMD or * not. Better make it 64. */ cmdr |= MCI_CMDR_MAXLAT_64CYC; if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN) cmdr |= MCI_CMDR_OPDCMD; data = cmd->data; if (data) { cmdr |= MCI_CMDR_START_XFER; if (data->flags & MMC_DATA_STREAM) cmdr |= MCI_CMDR_STREAM; else if (data->blocks > 1) cmdr |= MCI_CMDR_MULTI_BLOCK; else cmdr |= MCI_CMDR_BLOCK; if (data->flags & MMC_DATA_READ) cmdr |= MCI_CMDR_TRDIR_READ; } return cmdr; } static void atmci_start_command(struct atmel_mci *host, struct mmc_command *cmd, u32 cmd_flags) { WARN_ON(host->cmd); host->cmd = cmd; dev_vdbg(&host->pdev->dev, "start command: ARGR=0x%08x CMDR=0x%08x\n", cmd->arg, cmd_flags); mci_writel(host, ARGR, cmd->arg); mci_writel(host, CMDR, cmd_flags); } static void send_stop_cmd(struct atmel_mci *host, struct mmc_data *data) { atmci_start_command(host, data->stop, host->stop_cmdr); mci_writel(host, IER, MCI_CMDRDY); } #ifdef CONFIG_MMC_ATMELMCI_DMA static void atmci_dma_cleanup(struct atmel_mci *host) { struct mmc_data *data = host->data; dma_unmap_sg(&host->pdev->dev, data->sg, data->sg_len, ((data->flags & MMC_DATA_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)); } static void atmci_stop_dma(struct atmel_mci *host) { struct dma_chan *chan = host->data_chan; if (chan) { chan->device->device_terminate_all(chan); atmci_dma_cleanup(host); } else { /* Data transfer was stopped by the interrupt handler */ atmci_set_pending(host, EVENT_XFER_COMPLETE); mci_writel(host, IER, MCI_NOTBUSY); } } /* This function is called by the DMA driver from tasklet context. */ static void atmci_dma_complete(void *arg) { struct atmel_mci *host = arg; struct mmc_data *data = host->data; dev_vdbg(&host->pdev->dev, "DMA complete\n"); atmci_dma_cleanup(host); /* * If the card was removed, data will be NULL. No point trying * to send the stop command or waiting for NBUSY in this case. */ if (data) { atmci_set_pending(host, EVENT_XFER_COMPLETE); tasklet_schedule(&host->tasklet); /* * Regardless of what the documentation says, we have * to wait for NOTBUSY even after block read * operations. * * When the DMA transfer is complete, the controller * may still be reading the CRC from the card, i.e. * the data transfer is still in progress and we * haven't seen all the potential error bits yet. * * The interrupt handler will schedule a different * tasklet to finish things up when the data transfer * is completely done. * * We may not complete the mmc request here anyway * because the mmc layer may call back and cause us to * violate the "don't submit new operations from the * completion callback" rule of the dma engine * framework. */ mci_writel(host, IER, MCI_NOTBUSY); } } static int atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data) { struct dma_chan *chan; struct dma_async_tx_descriptor *desc; struct scatterlist *sg; unsigned int i; enum dma_data_direction direction; unsigned int sglen; /* * We don't do DMA on "complex" transfers, i.e. with * non-word-aligned buffers or lengths. Also, we don't bother * with all the DMA setup overhead for short transfers. */ if (data->blocks * data->blksz < ATMCI_DMA_THRESHOLD) return -EINVAL; if (data->blksz & 3) return -EINVAL; for_each_sg(data->sg, sg, data->sg_len, i) { if (sg->offset & 3 || sg->length & 3) return -EINVAL; } /* If we don't have a channel, we can't do DMA */ chan = host->dma.chan; if (chan) host->data_chan = chan; if (!chan) return -ENODEV; if (data->flags & MMC_DATA_READ) direction = DMA_FROM_DEVICE; else direction = DMA_TO_DEVICE; sglen = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, direction); if (sglen != data->sg_len) goto unmap_exit; desc = chan->device->device_prep_slave_sg(chan, data->sg, data->sg_len, direction, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) goto unmap_exit; host->dma.data_desc = desc; desc->callback = atmci_dma_complete; desc->callback_param = host; desc->tx_submit(desc); /* Go! */ chan->device->device_issue_pending(chan); return 0; unmap_exit: dma_unmap_sg(&host->pdev->dev, data->sg, sglen, direction); return -ENOMEM; } #else /* CONFIG_MMC_ATMELMCI_DMA */ static int atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data) { return -ENOSYS; } static void atmci_stop_dma(struct atmel_mci *host) { /* Data transfer was stopped by the interrupt handler */ atmci_set_pending(host, EVENT_XFER_COMPLETE); mci_writel(host, IER, MCI_NOTBUSY); } #endif /* CONFIG_MMC_ATMELMCI_DMA */ /* * Returns a mask of interrupt flags to be enabled after the whole * request has been prepared. */ static u32 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data) { u32 iflags; data->error = -EINPROGRESS; WARN_ON(host->data); host->sg = NULL; host->data = data; iflags = ATMCI_DATA_ERROR_FLAGS; if (atmci_submit_data_dma(host, data)) { host->data_chan = NULL; /* * Errata: MMC data write operation with less than 12 * bytes is impossible. * * Errata: MCI Transmit Data Register (TDR) FIFO * corruption when length is not multiple of 4. */ if (data->blocks * data->blksz < 12 || (data->blocks * data->blksz) & 3) host->need_reset = true; host->sg = data->sg; host->pio_offset = 0; if (data->flags & MMC_DATA_READ) iflags |= MCI_RXRDY; else iflags |= MCI_TXRDY; } return iflags; } static void atmci_start_request(struct atmel_mci *host, struct atmel_mci_slot *slot) { struct mmc_request *mrq; struct mmc_command *cmd; struct mmc_data *data; u32 iflags; u32 cmdflags; mrq = slot->mrq; host->cur_slot = slot; host->mrq = mrq; host->pending_events = 0; host->completed_events = 0; host->data_status = 0; if (host->need_reset) { mci_writel(host, CR, MCI_CR_SWRST); mci_writel(host, CR, MCI_CR_MCIEN); mci_writel(host, MR, host->mode_reg); host->need_reset = false; } mci_writel(host, SDCR, slot->sdc_reg); iflags = mci_readl(host, IMR); if (iflags) dev_warn(&slot->mmc->class_dev, "WARNING: IMR=0x%08x\n", iflags); if (unlikely(test_and_clear_bit(ATMCI_CARD_NEED_INIT, &slot->flags))) { /* Send init sequence (74 clock cycles) */ mci_writel(host, CMDR, MCI_CMDR_SPCMD_INIT); while (!(mci_readl(host, SR) & MCI_CMDRDY)) cpu_relax(); } data = mrq->data; if (data) { atmci_set_timeout(host, slot, data); /* Must set block count/size before sending command */ mci_writel(host, BLKR, MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz)); dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n", MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz)); } iflags = MCI_CMDRDY; cmd = mrq->cmd; cmdflags = atmci_prepare_command(slot->mmc, cmd); atmci_start_command(host, cmd, cmdflags); if (data) iflags |= atmci_submit_data(host, data); if (mrq->stop) { host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop); host->stop_cmdr |= MCI_CMDR_STOP_XFER; if (!(data->flags & MMC_DATA_WRITE)) host->stop_cmdr |= MCI_CMDR_TRDIR_READ; if (data->flags & MMC_DATA_STREAM) host->stop_cmdr |= MCI_CMDR_STREAM; else host->stop_cmdr |= MCI_CMDR_MULTI_BLOCK; } /* * We could have enabled interrupts earlier, but I suspect * that would open up a nice can of interesting race * conditions (e.g. command and data complete, but stop not * prepared yet.) */ mci_writel(host, IER, iflags); } static void atmci_queue_request(struct atmel_mci *host, struct atmel_mci_slot *slot, struct mmc_request *mrq) { dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n", host->state); spin_lock_bh(&host->lock); slot->mrq = mrq; if (host->state == STATE_IDLE) { host->state = STATE_SENDING_CMD; atmci_start_request(host, slot); } else { list_add_tail(&slot->queue_node, &host->queue); } spin_unlock_bh(&host->lock); } static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq) { struct atmel_mci_slot *slot = mmc_priv(mmc); struct atmel_mci *host = slot->host; struct mmc_data *data; WARN_ON(slot->mrq); /* * We may "know" the card is gone even though there's still an * electrical connection. If so, we really need to communicate * this to the MMC core since there won't be any more * interrupts as the card is completely removed. Otherwise, * the MMC core might believe the card is still there even * though the card was just removed very slowly. */ if (!test_bit(ATMCI_CARD_PRESENT, &slot->flags)) { mrq->cmd->error = -ENOMEDIUM; mmc_request_done(mmc, mrq); return; } /* We don't support multiple blocks of weird lengths. */ data = mrq->data; if (data && data->blocks > 1 && data->blksz & 3) { mrq->cmd->error = -EINVAL; mmc_request_done(mmc, mrq); } atmci_queue_request(host, slot, mrq); } static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) { struct atmel_mci_slot *slot = mmc_priv(mmc); struct atmel_mci *host = slot->host; unsigned int i; slot->sdc_reg &= ~MCI_SDCBUS_MASK; switch (ios->bus_width) { case MMC_BUS_WIDTH_1: slot->sdc_reg |= MCI_SDCBUS_1BIT; break; case MMC_BUS_WIDTH_4: slot->sdc_reg |= MCI_SDCBUS_4BIT; break; } if (ios->clock) { unsigned int clock_min = ~0U; u32 clkdiv; spin_lock_bh(&host->lock); if (!host->mode_reg) { clk_enable(host->mck); mci_writel(host, CR, MCI_CR_SWRST); mci_writel(host, CR, MCI_CR_MCIEN); } /* * Use mirror of ios->clock to prevent race with mmc * core ios update when finding the minimum. */ slot->clock = ios->clock; for (i = 0; i < ATMEL_MCI_MAX_NR_SLOTS; i++) { if (host->slot[i] && host->slot[i]->clock && host->slot[i]->clock < clock_min) clock_min = host->slot[i]->clock; } /* Calculate clock divider */ clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1; if (clkdiv > 255) { dev_warn(&mmc->class_dev, "clock %u too slow; using %lu\n", clock_min, host->bus_hz / (2 * 256)); clkdiv = 255; } host->mode_reg = MCI_MR_CLKDIV(clkdiv); /* * WRPROOF and RDPROOF prevent overruns/underruns by * stopping the clock when the FIFO is full/empty. * This state is not expected to last for long. */ if (mci_has_rwproof()) host->mode_reg |= (MCI_MR_WRPROOF | MCI_MR_RDPROOF); if (list_empty(&host->queue)) mci_writel(host, MR, host->mode_reg); else host->need_clock_update = true; spin_unlock_bh(&host->lock); } else { bool any_slot_active = false; spin_lock_bh(&host->lock); slot->clock = 0; for (i = 0; i < ATMEL_MCI_MAX_NR_SLOTS; i++) { if (host->slot[i] && host->slot[i]->clock) { any_slot_active = true; break; } } if (!any_slot_active) { mci_writel(host, CR, MCI_CR_MCIDIS); if (host->mode_reg) { mci_readl(host, MR); clk_disable(host->mck); } host->mode_reg = 0; } spin_unlock_bh(&host->lock); } switch (ios->power_mode) { case MMC_POWER_UP: set_bit(ATMCI_CARD_NEED_INIT, &slot->flags); break; default: /* * TODO: None of the currently available AVR32-based * boards allow MMC power to be turned off. Implement * power control when this can be tested properly. * * We also need to hook this into the clock management * somehow so that newly inserted cards aren't * subjected to a fast clock before we have a chance * to figure out what the maximum rate is. Currently, * there's no way to avoid this, and there never will * be for boards that don't support power control. */ break; } } static int atmci_get_ro(struct mmc_host *mmc) { int read_only = -ENOSYS; struct atmel_mci_slot *slot = mmc_priv(mmc); if (gpio_is_valid(slot->wp_pin)) { read_only = gpio_get_value(slot->wp_pin); dev_dbg(&mmc->class_dev, "card is %s\n", read_only ? "read-only" : "read-write"); } return read_only; } static int atmci_get_cd(struct mmc_host *mmc) { int present = -ENOSYS; struct atmel_mci_slot *slot = mmc_priv(mmc); if (gpio_is_valid(slot->detect_pin)) { present = !(gpio_get_value(slot->detect_pin) ^ slot->detect_is_active_high); dev_dbg(&mmc->class_dev, "card is %spresent\n", present ? "" : "not "); } return present; } static const struct mmc_host_ops atmci_ops = { .request = atmci_request, .set_ios = atmci_set_ios, .get_ro = atmci_get_ro, .get_cd = atmci_get_cd, }; /* Called with host->lock held */ static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq) __releases(&host->lock) __acquires(&host->lock) { struct atmel_mci_slot *slot = NULL; struct mmc_host *prev_mmc = host->cur_slot->mmc; WARN_ON(host->cmd || host->data); /* * Update the MMC clock rate if necessary. This may be * necessary if set_ios() is called when a different slot is * busy transfering data. */ if (host->need_clock_update) mci_writel(host, MR, host->mode_reg); host->cur_slot->mrq = NULL; host->mrq = NULL; if (!list_empty(&host->queue)) { slot = list_entry(host->queue.next, struct atmel_mci_slot, queue_node); list_del(&slot->queue_node); dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n", mmc_hostname(slot->mmc)); host->state = STATE_SENDING_CMD; atmci_start_request(host, slot); } else { dev_vdbg(&host->pdev->dev, "list empty\n"); host->state = STATE_IDLE; } spin_unlock(&host->lock); mmc_request_done(prev_mmc, mrq); spin_lock(&host->lock); } static void atmci_command_complete(struct atmel_mci *host, struct mmc_command *cmd) { u32 status = host->cmd_status; /* Read the response from the card (up to 16 bytes) */ cmd->resp[0] = mci_readl(host, RSPR); cmd->resp[1] = mci_readl(host, RSPR); cmd->resp[2] = mci_readl(host, RSPR); cmd->resp[3] = mci_readl(host, RSPR); if (status & MCI_RTOE) cmd->error = -ETIMEDOUT; else if ((cmd->flags & MMC_RSP_CRC) && (status & MCI_RCRCE)) cmd->error = -EILSEQ; else if (status & (MCI_RINDE | MCI_RDIRE | MCI_RENDE)) cmd->error = -EIO; else cmd->error = 0; if (cmd->error) { dev_dbg(&host->pdev->dev, "command error: status=0x%08x\n", status); if (cmd->data) { host->data = NULL; atmci_stop_dma(host); mci_writel(host, IDR, MCI_NOTBUSY | MCI_TXRDY | MCI_RXRDY | ATMCI_DATA_ERROR_FLAGS); } } } static void atmci_detect_change(unsigned long data) { struct atmel_mci_slot *slot = (struct atmel_mci_slot *)data; bool present; bool present_old; /* * atmci_cleanup_slot() sets the ATMCI_SHUTDOWN flag before * freeing the interrupt. We must not re-enable the interrupt * if it has been freed, and if we're shutting down, it * doesn't really matter whether the card is present or not. */ smp_rmb(); if (test_bit(ATMCI_SHUTDOWN, &slot->flags)) return; enable_irq(gpio_to_irq(slot->detect_pin)); present = !(gpio_get_value(slot->detect_pin) ^ slot->detect_is_active_high); present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags); dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n", present, present_old); if (present != present_old) { struct atmel_mci *host = slot->host; struct mmc_request *mrq; dev_dbg(&slot->mmc->class_dev, "card %s\n", present ? "inserted" : "removed"); spin_lock(&host->lock); if (!present) clear_bit(ATMCI_CARD_PRESENT, &slot->flags); else set_bit(ATMCI_CARD_PRESENT, &slot->flags); /* Clean up queue if present */ mrq = slot->mrq; if (mrq) { if (mrq == host->mrq) { /* * Reset controller to terminate any ongoing * commands or data transfers. */ mci_writel(host, CR, MCI_CR_SWRST); mci_writel(host, CR, MCI_CR_MCIEN); mci_writel(host, MR, host->mode_reg); host->data = NULL; host->cmd = NULL; switch (host->state) { case STATE_IDLE: break; case STATE_SENDING_CMD: mrq->cmd->error = -ENOMEDIUM; if (!mrq->data) break; /* fall through */ case STATE_SENDING_DATA: mrq->data->error = -ENOMEDIUM; atmci_stop_dma(host); break; case STATE_DATA_BUSY: case STATE_DATA_ERROR: if (mrq->data->error == -EINPROGRESS) mrq->data->error = -ENOMEDIUM; if (!mrq->stop) break; /* fall through */ case STATE_SENDING_STOP: mrq->stop->error = -ENOMEDIUM; break; } atmci_request_end(host, mrq); } else { list_del(&slot->queue_node); mrq->cmd->error = -ENOMEDIUM; if (mrq->data) mrq->data->error = -ENOMEDIUM; if (mrq->stop) mrq->stop->error = -ENOMEDIUM; spin_unlock(&host->lock); mmc_request_done(slot->mmc, mrq); spin_lock(&host->lock); } } spin_unlock(&host->lock); mmc_detect_change(slot->mmc, 0); } } static void atmci_tasklet_func(unsigned long priv) { struct atmel_mci *host = (struct atmel_mci *)priv; struct mmc_request *mrq = host->mrq; struct mmc_data *data = host->data; struct mmc_command *cmd = host->cmd; enum atmel_mci_state state = host->state; enum atmel_mci_state prev_state; u32 status; spin_lock(&host->lock); state = host->state; dev_vdbg(&host->pdev->dev, "tasklet: state %u pending/completed/mask %lx/%lx/%x\n", state, host->pending_events, host->completed_events, mci_readl(host, IMR)); do { prev_state = state; switch (state) { case STATE_IDLE: break; case STATE_SENDING_CMD: if (!atmci_test_and_clear_pending(host, EVENT_CMD_COMPLETE)) break; host->cmd = NULL; atmci_set_completed(host, EVENT_CMD_COMPLETE); atmci_command_complete(host, mrq->cmd); if (!mrq->data || cmd->error) { atmci_request_end(host, host->mrq); goto unlock; } prev_state = state = STATE_SENDING_DATA; /* fall through */ case STATE_SENDING_DATA: if (atmci_test_and_clear_pending(host, EVENT_DATA_ERROR)) { atmci_stop_dma(host); if (data->stop) send_stop_cmd(host, data); state = STATE_DATA_ERROR; break; } if (!atmci_test_and_clear_pending(host, EVENT_XFER_COMPLETE)) break; atmci_set_completed(host, EVENT_XFER_COMPLETE); prev_state = state = STATE_DATA_BUSY; /* fall through */ case STATE_DATA_BUSY: if (!atmci_test_and_clear_pending(host, EVENT_DATA_COMPLETE)) break; host->data = NULL; atmci_set_completed(host, EVENT_DATA_COMPLETE); status = host->data_status; if (unlikely(status & ATMCI_DATA_ERROR_FLAGS)) { if (status & MCI_DTOE) { dev_dbg(&host->pdev->dev, "data timeout error\n"); data->error = -ETIMEDOUT; } else if (status & MCI_DCRCE) { dev_dbg(&host->pdev->dev, "data CRC error\n"); data->error = -EILSEQ; } else { dev_dbg(&host->pdev->dev, "data FIFO error (status=%08x)\n", status); data->error = -EIO; } } else { data->bytes_xfered = data->blocks * data->blksz; data->error = 0; } if (!data->stop) { atmci_request_end(host, host->mrq); goto unlock; } prev_state = state = STATE_SENDING_STOP; if (!data->error) send_stop_cmd(host, data); /* fall through */ case STATE_SENDING_STOP: if (!atmci_test_and_clear_pending(host, EVENT_CMD_COMPLETE)) break; host->cmd = NULL; atmci_command_complete(host, mrq->stop); atmci_request_end(host, host->mrq); goto unlock; case STATE_DATA_ERROR: if (!atmci_test_and_clear_pending(host, EVENT_XFER_COMPLETE)) break; state = STATE_DATA_BUSY; break; } } while (state != prev_state); host->state = state; unlock: spin_unlock(&host->lock); } static void atmci_read_data_pio(struct atmel_mci *host) { struct scatterlist *sg = host->sg; void *buf = sg_virt(sg); unsigned int offset = host->pio_offset; struct mmc_data *data = host->data; u32 value; u32 status; unsigned int nbytes = 0; do { value = mci_readl(host, RDR); if (likely(offset + 4 <= sg->length)) { put_unaligned(value, (u32 *)(buf + offset)); offset += 4; nbytes += 4; if (offset == sg->length) { flush_dcache_page(sg_page(sg)); host->sg = sg = sg_next(sg); if (!sg) goto done; offset = 0; buf = sg_virt(sg); } } else { unsigned int remaining = sg->length - offset; memcpy(buf + offset, &value, remaining); nbytes += remaining; flush_dcache_page(sg_page(sg)); host->sg = sg = sg_next(sg); if (!sg) goto done; offset = 4 - remaining; buf = sg_virt(sg); memcpy(buf, (u8 *)&value + remaining, offset); nbytes += offset; } status = mci_readl(host, SR); if (status & ATMCI_DATA_ERROR_FLAGS) { mci_writel(host, IDR, (MCI_NOTBUSY | MCI_RXRDY | ATMCI_DATA_ERROR_FLAGS)); host->data_status = status; data->bytes_xfered += nbytes; smp_wmb(); atmci_set_pending(host, EVENT_DATA_ERROR); tasklet_schedule(&host->tasklet); return; } } while (status & MCI_RXRDY); host->pio_offset = offset; data->bytes_xfered += nbytes; return; done: mci_writel(host, IDR, MCI_RXRDY); mci_writel(host, IER, MCI_NOTBUSY); data->bytes_xfered += nbytes; smp_wmb(); atmci_set_pending(host, EVENT_XFER_COMPLETE); } static void atmci_write_data_pio(struct atmel_mci *host) { struct scatterlist *sg = host->sg; void *buf = sg_virt(sg); unsigned int offset = host->pio_offset; struct mmc_data *data = host->data; u32 value; u32 status; unsigned int nbytes = 0; do { if (likely(offset + 4 <= sg->length)) { value = get_unaligned((u32 *)(buf + offset)); mci_writel(host, TDR, value); offset += 4; nbytes += 4; if (offset == sg->length) { host->sg = sg = sg_next(sg); if (!sg) goto done; offset = 0; buf = sg_virt(sg); } } else { unsigned int remaining = sg->length - offset; value = 0; memcpy(&value, buf + offset, remaining); nbytes += remaining; host->sg = sg = sg_next(sg); if (!sg) { mci_writel(host, TDR, value); goto done; } offset = 4 - remaining; buf = sg_virt(sg); memcpy((u8 *)&value + remaining, buf, offset); mci_writel(host, TDR, value); nbytes += offset; } status = mci_readl(host, SR); if (status & ATMCI_DATA_ERROR_FLAGS) { mci_writel(host, IDR, (MCI_NOTBUSY | MCI_TXRDY | ATMCI_DATA_ERROR_FLAGS)); host->data_status = status; data->bytes_xfered += nbytes; smp_wmb(); atmci_set_pending(host, EVENT_DATA_ERROR); tasklet_schedule(&host->tasklet); return; } } while (status & MCI_TXRDY); host->pio_offset = offset; data->bytes_xfered += nbytes; return; done: mci_writel(host, IDR, MCI_TXRDY); mci_writel(host, IER, MCI_NOTBUSY); data->bytes_xfered += nbytes; smp_wmb(); atmci_set_pending(host, EVENT_XFER_COMPLETE); } static void atmci_cmd_interrupt(struct atmel_mci *host, u32 status) { mci_writel(host, IDR, MCI_CMDRDY); host->cmd_status = status; smp_wmb(); atmci_set_pending(host, EVENT_CMD_COMPLETE); tasklet_schedule(&host->tasklet); } static irqreturn_t atmci_interrupt(int irq, void *dev_id) { struct atmel_mci *host = dev_id; u32 status, mask, pending; unsigned int pass_count = 0; do { status = mci_readl(host, SR); mask = mci_readl(host, IMR); pending = status & mask; if (!pending) break; if (pending & ATMCI_DATA_ERROR_FLAGS) { mci_writel(host, IDR, ATMCI_DATA_ERROR_FLAGS | MCI_RXRDY | MCI_TXRDY); pending &= mci_readl(host, IMR); host->data_status = status; smp_wmb(); atmci_set_pending(host, EVENT_DATA_ERROR); tasklet_schedule(&host->tasklet); } if (pending & MCI_NOTBUSY) { mci_writel(host, IDR, ATMCI_DATA_ERROR_FLAGS | MCI_NOTBUSY); if (!host->data_status) host->data_status = status; smp_wmb(); atmci_set_pending(host, EVENT_DATA_COMPLETE); tasklet_schedule(&host->tasklet); } if (pending & MCI_RXRDY) atmci_read_data_pio(host); if (pending & MCI_TXRDY) atmci_write_data_pio(host); if (pending & MCI_CMDRDY) atmci_cmd_interrupt(host, status); } while (pass_count++ < 5); return pass_count ? IRQ_HANDLED : IRQ_NONE; } static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id) { struct atmel_mci_slot *slot = dev_id; /* * Disable interrupts until the pin has stabilized and check * the state then. Use mod_timer() since we may be in the * middle of the timer routine when this interrupt triggers. */ disable_irq_nosync(irq); mod_timer(&slot->detect_timer, jiffies + msecs_to_jiffies(20)); return IRQ_HANDLED; } static int __init atmci_init_slot(struct atmel_mci *host, struct mci_slot_pdata *slot_data, unsigned int id, u32 sdc_reg) { struct mmc_host *mmc; struct atmel_mci_slot *slot; mmc = mmc_alloc_host(sizeof(struct atmel_mci_slot), &host->pdev->dev); if (!mmc) return -ENOMEM; slot = mmc_priv(mmc); slot->mmc = mmc; slot->host = host; slot->detect_pin = slot_data->detect_pin; slot->wp_pin = slot_data->wp_pin; slot->detect_is_active_high = slot_data->detect_is_active_high; slot->sdc_reg = sdc_reg; mmc->ops = &atmci_ops; mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512); mmc->f_max = host->bus_hz / 2; mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34; if (slot_data->bus_width >= 4) mmc->caps |= MMC_CAP_4_BIT_DATA; mmc->max_hw_segs = 64; mmc->max_phys_segs = 64; mmc->max_req_size = 32768 * 512; mmc->max_blk_size = 32768; mmc->max_blk_count = 512; /* Assume card is present initially */ set_bit(ATMCI_CARD_PRESENT, &slot->flags); if (gpio_is_valid(slot->detect_pin)) { if (gpio_request(slot->detect_pin, "mmc_detect")) { dev_dbg(&mmc->class_dev, "no detect pin available\n"); slot->detect_pin = -EBUSY; } else if (gpio_get_value(slot->detect_pin) ^ slot->detect_is_active_high) { clear_bit(ATMCI_CARD_PRESENT, &slot->flags); } } if (!gpio_is_valid(slot->detect_pin)) mmc->caps |= MMC_CAP_NEEDS_POLL; if (gpio_is_valid(slot->wp_pin)) { if (gpio_request(slot->wp_pin, "mmc_wp")) { dev_dbg(&mmc->class_dev, "no WP pin available\n"); slot->wp_pin = -EBUSY; } } host->slot[id] = slot; mmc_add_host(mmc); if (gpio_is_valid(slot->detect_pin)) { int ret; setup_timer(&slot->detect_timer, atmci_detect_change, (unsigned long)slot); ret = request_irq(gpio_to_irq(slot->detect_pin), atmci_detect_interrupt, IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING, "mmc-detect", slot); if (ret) { dev_dbg(&mmc->class_dev, "could not request IRQ %d for detect pin\n", gpio_to_irq(slot->detect_pin)); gpio_free(slot->detect_pin); slot->detect_pin = -EBUSY; } } atmci_init_debugfs(slot); return 0; } static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot, unsigned int id) { /* Debugfs stuff is cleaned up by mmc core */ set_bit(ATMCI_SHUTDOWN, &slot->flags); smp_wmb(); mmc_remove_host(slot->mmc); if (gpio_is_valid(slot->detect_pin)) { int pin = slot->detect_pin; free_irq(gpio_to_irq(pin), slot); del_timer_sync(&slot->detect_timer); gpio_free(pin); } if (gpio_is_valid(slot->wp_pin)) gpio_free(slot->wp_pin); slot->host->slot[id] = NULL; mmc_free_host(slot->mmc); } #ifdef CONFIG_MMC_ATMELMCI_DMA static bool filter(struct dma_chan *chan, void *slave) { struct dw_dma_slave *dws = slave; if (dws->dma_dev == chan->device->dev) { chan->private = dws; return true; } else return false; } #endif static int __init atmci_probe(struct platform_device *pdev) { struct mci_platform_data *pdata; struct atmel_mci *host; struct resource *regs; unsigned int nr_slots; int irq; int ret; regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!regs) return -ENXIO; pdata = pdev->dev.platform_data; if (!pdata) return -ENXIO; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; host = kzalloc(sizeof(struct atmel_mci), GFP_KERNEL); if (!host) return -ENOMEM; host->pdev = pdev; spin_lock_init(&host->lock); INIT_LIST_HEAD(&host->queue); host->mck = clk_get(&pdev->dev, "mci_clk"); if (IS_ERR(host->mck)) { ret = PTR_ERR(host->mck); goto err_clk_get; } ret = -ENOMEM; host->regs = ioremap(regs->start, regs->end - regs->start + 1); if (!host->regs) goto err_ioremap; clk_enable(host->mck); mci_writel(host, CR, MCI_CR_SWRST); host->bus_hz = clk_get_rate(host->mck); clk_disable(host->mck); host->mapbase = regs->start; tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host); ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host); if (ret) goto err_request_irq; #ifdef CONFIG_MMC_ATMELMCI_DMA if (pdata->dma_slave.dma_dev) { struct dw_dma_slave *dws = &pdata->dma_slave; dma_cap_mask_t mask; dws->tx_reg = regs->start + MCI_TDR; dws->rx_reg = regs->start + MCI_RDR; /* Try to grab a DMA channel */ dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); host->dma.chan = dma_request_channel(mask, filter, dws); } if (!host->dma.chan) dev_notice(&pdev->dev, "DMA not available, using PIO\n"); #endif /* CONFIG_MMC_ATMELMCI_DMA */ platform_set_drvdata(pdev, host); /* We need at least one slot to succeed */ nr_slots = 0; ret = -ENODEV; if (pdata->slot[0].bus_width) { ret = atmci_init_slot(host, &pdata->slot[0], MCI_SDCSEL_SLOT_A, 0); if (!ret) nr_slots++; } if (pdata->slot[1].bus_width) { ret = atmci_init_slot(host, &pdata->slot[1], MCI_SDCSEL_SLOT_B, 1); if (!ret) nr_slots++; } if (!nr_slots) { dev_err(&pdev->dev, "init failed: no slot defined\n"); goto err_init_slot; } dev_info(&pdev->dev, "Atmel MCI controller at 0x%08lx irq %d, %u slots\n", host->mapbase, irq, nr_slots); return 0; err_init_slot: #ifdef CONFIG_MMC_ATMELMCI_DMA if (host->dma.chan) dma_release_channel(host->dma.chan); #endif free_irq(irq, host); err_request_irq: iounmap(host->regs); err_ioremap: clk_put(host->mck); err_clk_get: kfree(host); return ret; } static int __exit atmci_remove(struct platform_device *pdev) { struct atmel_mci *host = platform_get_drvdata(pdev); unsigned int i; platform_set_drvdata(pdev, NULL); for (i = 0; i < ATMEL_MCI_MAX_NR_SLOTS; i++) { if (host->slot[i]) atmci_cleanup_slot(host->slot[i], i); } clk_enable(host->mck); mci_writel(host, IDR, ~0UL); mci_writel(host, CR, MCI_CR_MCIDIS); mci_readl(host, SR); clk_disable(host->mck); #ifdef CONFIG_MMC_ATMELMCI_DMA if (host->dma.chan) dma_release_channel(host->dma.chan); #endif free_irq(platform_get_irq(pdev, 0), host); iounmap(host->regs); clk_put(host->mck); kfree(host); return 0; } static struct platform_driver atmci_driver = { .remove = __exit_p(atmci_remove), .driver = { .name = "atmel_mci", }, }; static int __init atmci_init(void) { return platform_driver_probe(&atmci_driver, atmci_probe); } static void __exit atmci_exit(void) { platform_driver_unregister(&atmci_driver); } late_initcall(atmci_init); /* try to load after dma driver when built-in */ module_exit(atmci_exit); MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver"); MODULE_AUTHOR("Haavard Skinnemoen "); MODULE_LICENSE("GPL v2");