diff options
author | Pierre Ossman <drzeus@drzeus.cx> | 2008-10-12 11:08:46 +0200 |
---|---|---|
committer | Pierre Ossman <drzeus@drzeus.cx> | 2008-10-12 11:08:46 +0200 |
commit | 6ee6c6adf1cfebbf432b8d1f204c7f96e395933e (patch) | |
tree | cf8f017f44b768445eecb6698c47d479c6b46a01 /drivers | |
parent | 162350eb75fcb81ec0ea34f042f1deddb759aea8 (diff) | |
parent | 5e7184ae0dd49456387e8b1cdebc6b2c92fc6d51 (diff) |
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/atmel-mci-2.6.28
Conflicts:
drivers/mmc/host/atmel-mci.c
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/mmc/host/Kconfig | 11 | ||||
-rw-r--r-- | drivers/mmc/host/atmel-mci-regs.h | 6 | ||||
-rw-r--r-- | drivers/mmc/host/atmel-mci.c | 1352 |
3 files changed, 987 insertions, 382 deletions
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index 38468b2bd1af..dfa585f7feaf 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig @@ -114,6 +114,17 @@ config MMC_ATMELMCI If unsure, say N. +config MMC_ATMELMCI_DMA + bool "Atmel MCI DMA support (EXPERIMENTAL)" + depends on MMC_ATMELMCI && DMA_ENGINE && EXPERIMENTAL + help + Say Y here to have the Atmel MCI driver use a DMA engine to + do data transfers and thus increase the throughput and + reduce the CPU utilization. Note that this is highly + experimental and may cause the driver to lock up. + + If unsure, say N. + config MMC_IMX tristate "Motorola i.MX Multimedia Card Interface support" depends on ARCH_IMX diff --git a/drivers/mmc/host/atmel-mci-regs.h b/drivers/mmc/host/atmel-mci-regs.h index 26bd80e65031..b58364ed6bba 100644 --- a/drivers/mmc/host/atmel-mci-regs.h +++ b/drivers/mmc/host/atmel-mci-regs.h @@ -25,8 +25,10 @@ #define MCI_SDCR 0x000c /* SD Card / SDIO */ # define MCI_SDCSEL_SLOT_A ( 0 << 0) /* Select SD slot A */ # define MCI_SDCSEL_SLOT_B ( 1 << 0) /* Select SD slot A */ -# define MCI_SDCBUS_1BIT ( 0 << 7) /* 1-bit data bus */ -# define MCI_SDCBUS_4BIT ( 1 << 7) /* 4-bit data bus */ +# define MCI_SDCSEL_MASK ( 3 << 0) +# define MCI_SDCBUS_1BIT ( 0 << 6) /* 1-bit data bus */ +# define MCI_SDCBUS_4BIT ( 2 << 6) /* 4-bit data bus */ +# define MCI_SDCBUS_MASK ( 3 << 6) #define MCI_ARGR 0x0010 /* Command Argument */ #define MCI_CMDR 0x0014 /* Command */ # define MCI_CMDR_CMDNB(x) ((x) << 0) /* Command Opcode */ diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 00008967ef7a..7a3f2436b011 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -11,6 +11,8 @@ #include <linux/clk.h> #include <linux/debugfs.h> #include <linux/device.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/gpio.h> #include <linux/init.h> @@ -33,64 +35,178 @@ #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_DATA_ERROR, - EVENT_DATA_COMPLETE, - EVENT_STOP_SENT, - EVENT_STOP_COMPLETE, 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_client client; + 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 { - struct mmc_host *mmc; + 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_status; u32 stop_cmdr; - u32 mode_reg; - u32 sdc_reg; - struct tasklet_struct tasklet; unsigned long pending_events; unsigned long completed_events; + enum atmel_mci_state state; + struct list_head queue; - int present; - int detect_pin; - int wp_pin; - - /* For detect pin debouncing */ - struct timer_list detect_timer; - + 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_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; + + struct timer_list detect_timer; }; -#define atmci_is_completed(host, event) \ - test_bit(event, &host->completed_events) #define atmci_test_and_clear_pending(host, event) \ test_and_clear_bit(event, &host->pending_events) -#define atmci_test_and_set_completed(host, event) \ - test_and_set_bit(event, &host->completed_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) -#define atmci_clear_pending(host, event) \ - clear_bit(event, &host->pending_events) /* * The debugfs stuff below is mostly optimized away when @@ -98,14 +214,15 @@ struct atmel_mci { */ static int atmci_req_show(struct seq_file *s, void *v) { - struct atmel_mci *host = s->private; - struct mmc_request *mrq = host->mrq; + 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_irq(&host->mmc->lock); + spin_lock_bh(&slot->host->lock); + mrq = slot->mrq; if (mrq) { cmd = mrq->cmd; @@ -130,7 +247,7 @@ static int atmci_req_show(struct seq_file *s, void *v) stop->resp[2], stop->error); } - spin_unlock_irq(&host->mmc->lock); + spin_unlock_bh(&slot->host->lock); return 0; } @@ -193,12 +310,16 @@ static int atmci_regs_show(struct seq_file *s, void *v) if (!buf) return -ENOMEM; - /* Grab a more or less consistent snapshot */ - spin_lock_irq(&host->mmc->lock); + /* + * 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_irq(&host->mmc->lock); + spin_unlock_bh(&host->lock); seq_printf(s, "MR:\t0x%08x%s%s CLKDIV=%u\n", buf[MCI_MR / 4], @@ -236,13 +357,13 @@ static const struct file_operations atmci_regs_fops = { .release = single_release, }; -static void atmci_init_debugfs(struct atmel_mci *host) +static void atmci_init_debugfs(struct atmel_mci_slot *slot) { - struct mmc_host *mmc; - struct dentry *root; - struct dentry *node; + struct mmc_host *mmc = slot->mmc; + struct atmel_mci *host = slot->host; + struct dentry *root; + struct dentry *node; - mmc = host->mmc; root = mmc->debugfs_root; if (!root) return; @@ -254,7 +375,11 @@ static void atmci_init_debugfs(struct atmel_mci *host) if (!node) goto err; - node = debugfs_create_file("req", S_IRUSR, root, host, &atmci_req_fops); + 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; @@ -271,25 +396,7 @@ static void atmci_init_debugfs(struct atmel_mci *host) return; err: - dev_err(&host->pdev->dev, - "failed to initialize debugfs for controller\n"); -} - -static void atmci_enable(struct atmel_mci *host) -{ - clk_enable(host->mck); - mci_writel(host, CR, MCI_CR_MCIEN); - mci_writel(host, MR, host->mode_reg); - mci_writel(host, SDCR, host->sdc_reg); -} - -static void atmci_disable(struct atmel_mci *host) -{ - mci_writel(host, CR, MCI_CR_SWRST); - - /* Stall until write is complete, then disable the bus clock */ - mci_readl(host, SR); - clk_disable(host->mck); + dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n"); } static inline unsigned int ns_to_clocks(struct atmel_mci *host, @@ -299,7 +406,7 @@ static inline unsigned int ns_to_clocks(struct atmel_mci *host, } static void atmci_set_timeout(struct atmel_mci *host, - struct mmc_data *data) + struct atmel_mci_slot *slot, struct mmc_data *data) { static unsigned dtomul_to_shift[] = { 0, 4, 7, 8, 10, 12, 16, 20 @@ -322,7 +429,7 @@ static void atmci_set_timeout(struct atmel_mci *host, dtocyc = 15; } - dev_vdbg(&host->mmc->class_dev, "setting timeout to %u cycles\n", + 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))); } @@ -375,15 +482,12 @@ static u32 atmci_prepare_command(struct mmc_host *mmc, } static void atmci_start_command(struct atmel_mci *host, - struct mmc_command *cmd, - u32 cmd_flags) + struct mmc_command *cmd, u32 cmd_flags) { - /* Must read host->cmd after testing event flags */ - smp_rmb(); WARN_ON(host->cmd); host->cmd = cmd; - dev_vdbg(&host->mmc->class_dev, + dev_vdbg(&host->pdev->dev, "start command: ARGR=0x%08x CMDR=0x%08x\n", cmd->arg, cmd_flags); @@ -391,34 +495,157 @@ static void atmci_start_command(struct atmel_mci *host, mci_writel(host, CMDR, cmd_flags); } -static void send_stop_cmd(struct mmc_host *mmc, struct mmc_data *data) +static void send_stop_cmd(struct atmel_mci *host, struct mmc_data *data) { - struct atmel_mci *host = mmc_priv(mmc); - atmci_start_command(host, data->stop, host->stop_cmdr); mci_writel(host, IER, MCI_CMDRDY); } -static void atmci_request_end(struct mmc_host *mmc, struct mmc_request *mrq) +#ifdef CONFIG_MMC_ATMELMCI_DMA +static void atmci_dma_cleanup(struct atmel_mci *host) { - struct atmel_mci *host = mmc_priv(mmc); + struct mmc_data *data = host->data; - WARN_ON(host->cmd || host->data); - host->mrq = NULL; + 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; + + /* + * 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) { + dma_chan_get(chan); + host->data_chan = chan; + } + + if (!chan) + return -ENODEV; + + if (data->flags & MMC_DATA_READ) + direction = DMA_FROM_DEVICE; + else + direction = DMA_TO_DEVICE; + + desc = chan->device->device_prep_slave_sg(chan, + data->sg, data->sg_len, direction, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) + return -ENOMEM; - atmci_disable(host); + host->dma.data_desc = desc; + desc->callback = atmci_dma_complete; + desc->callback_param = host; + desc->tx_submit(desc); - mmc_request_done(mmc, mrq); + /* Go! */ + chan->device->device_issue_pending(chan); + + return 0; +} + +#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 mmc_host *mmc, struct mmc_data *data) +static u32 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data) { - struct atmel_mci *host = mmc_priv(mmc); - u32 iflags; + u32 iflags; data->error = -EINPROGRESS; @@ -426,77 +653,89 @@ static u32 atmci_submit_data(struct mmc_host *mmc, struct mmc_data *data) host->sg = NULL; host->data = data; - dev_vdbg(&mmc->class_dev, "BLKR=0x%08x\n", - MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz)); - iflags = ATMCI_DATA_ERROR_FLAGS; - host->sg = data->sg; - host->pio_offset = 0; - if (data->flags & MMC_DATA_READ) - iflags |= MCI_RXRDY; - else - iflags |= MCI_TXRDY; + 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_request(struct mmc_host *mmc, struct mmc_request *mrq) +static void atmci_start_request(struct atmel_mci *host, + struct atmel_mci_slot *slot) { - struct atmel_mci *host = mmc_priv(mmc); - struct mmc_data *data; + struct mmc_request *mrq; struct mmc_command *cmd; + struct mmc_data *data; u32 iflags; - u32 cmdflags = 0; - - iflags = mci_readl(host, IMR); - if (iflags) - dev_warn(&mmc->class_dev, "WARNING: IMR=0x%08x\n", - mci_readl(host, IMR)); - - WARN_ON(host->mrq != NULL); - - /* - * 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 (!host->present) { - mrq->cmd->error = -ENOMEDIUM; - mmc_request_done(mmc, mrq); - return; - } + u32 cmdflags; + mrq = slot->mrq; + host->cur_slot = slot; host->mrq = mrq; + host->pending_events = 0; host->completed_events = 0; + host->data_status = 0; - atmci_enable(host); + 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); - /* We don't support multiple blocks of weird lengths. */ + 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) { - if (data->blocks > 1 && data->blksz & 3) - goto fail; - atmci_set_timeout(host, 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(mmc, cmd); + cmdflags = atmci_prepare_command(slot->mmc, cmd); atmci_start_command(host, cmd, cmdflags); if (data) - iflags |= atmci_submit_data(mmc, data); + iflags |= atmci_submit_data(host, data); if (mrq->stop) { - host->stop_cmdr = atmci_prepare_command(mmc, 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; @@ -513,59 +752,156 @@ static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq) * prepared yet.) */ mci_writel(host, IER, iflags); +} - return; +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); +} -fail: - atmci_disable(host); - host->mrq = NULL; - mrq->cmd->error = -EINVAL; - mmc_request_done(mmc, mrq); +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 *host = mmc_priv(mmc); + 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; - /* Set clock rate */ - clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * ios->clock) - 1; + 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", - ios->clock, host->bus_hz / (2 * 256)); + clock_min, host->bus_hz / (2 * 256)); clkdiv = 255; } + /* + * 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. + */ host->mode_reg = MCI_MR_CLKDIV(clkdiv) | MCI_MR_WRPROOF | MCI_MR_RDPROOF; - } - switch (ios->bus_width) { - case MMC_BUS_WIDTH_1: - host->sdc_reg = 0; - break; - case MMC_BUS_WIDTH_4: - host->sdc_reg = MCI_SDCBUS_4BIT; - break; + 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_ON: - /* Send init sequence (74 clock cycles) */ - atmci_enable(host); - mci_writel(host, CMDR, MCI_CMDR_SPCMD_INIT); - while (!(mci_readl(host, SR) & MCI_CMDRDY)) - cpu_relax(); - atmci_disable(host); + 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; } @@ -573,31 +909,82 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) static int atmci_get_ro(struct mmc_host *mmc) { - int read_only = 0; - struct atmel_mci *host = mmc_priv(mmc); + int read_only = -ENOSYS; + struct atmel_mci_slot *slot = mmc_priv(mmc); - if (gpio_is_valid(host->wp_pin)) { - read_only = gpio_get_value(host->wp_pin); + 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"); - } else { - dev_dbg(&mmc->class_dev, - "no pin for checking read-only switch." - " Assuming write-enable.\n"); } return read_only; } -static struct mmc_host_ops atmci_ops = { +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); + 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) + 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); @@ -614,11 +1001,12 @@ static void atmci_command_complete(struct atmel_mci *host, cmd->error = 0; if (cmd->error) { - dev_dbg(&host->mmc->class_dev, + 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); @@ -628,146 +1016,222 @@ static void atmci_command_complete(struct atmel_mci *host, static void atmci_detect_change(unsigned long data) { - struct atmel_mci *host = (struct atmel_mci *)data; - struct mmc_request *mrq = host->mrq; - int present; + struct atmel_mci_slot *slot = (struct atmel_mci_slot *)data; + bool present; + bool present_old; /* - * atmci_remove() sets detect_pin to -1 before freeing the - * interrupt. We must not re-enable the interrupt if it has - * been freed. + * 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 (!gpio_is_valid(host->detect_pin)) + if (test_bit(ATMCI_SHUTDOWN, &slot->flags)) return; - enable_irq(gpio_to_irq(host->detect_pin)); - present = !gpio_get_value(host->detect_pin); + enable_irq(gpio_to_irq(slot->detect_pin)); + present = !gpio_get_value(slot->detect_pin); + present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags); + + dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n", + present, present_old); - dev_vdbg(&host->pdev->dev, "detect change: %d (was %d)\n", - present, host->present); + if (present != present_old) { + struct atmel_mci *host = slot->host; + struct mmc_request *mrq; - if (present != host->present) { - dev_dbg(&host->mmc->class_dev, "card %s\n", + dev_dbg(&slot->mmc->class_dev, "card %s\n", present ? "inserted" : "removed"); - host->present = present; - /* Reset controller if card is gone */ - if (!present) { - mci_writel(host, CR, MCI_CR_SWRST); - mci_writel(host, IDR, ~0UL); - mci_writel(host, CR, MCI_CR_MCIEN); - } + 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) { - /* - * Reset controller to terminate any ongoing - * commands or data transfers. - */ - mci_writel(host, CR, MCI_CR_SWRST); + 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); - if (!atmci_is_completed(host, EVENT_CMD_COMPLETE)) - mrq->cmd->error = -ENOMEDIUM; - - if (mrq->data && !atmci_is_completed(host, - EVENT_DATA_COMPLETE)) { host->data = NULL; - mrq->data->error = -ENOMEDIUM; + host->cmd = NULL; + + switch (host->state) { + case STATE_IDLE: + break; + case STATE_SENDING_CMD: + mrq->cmd->error = -ENOMEDIUM; + if (!mrq->data) |