linux/drivers/mmc/host/atmel-mci.c
Ludovic Desroches 7e8ba228d9 mmc: atmel-mci: fix a potential issue about pending PDC interrupts
This patch fixes a potential issue about PDC interrupts. For example we
have a ENDRX pending interrupt and a RXBUFF pending interrupt. We have
received the RXBUFF interrupt but the transfer is not finished (so we
didn't have time to give a new buffer to the PDC controller). Then we
will compute ENDRX interrupt and we will give a new buffer to the PDC
controller, just after we will compute the RXBUFF interrupt and give
one or two new buffers to the PDC controller but we are not sure that
the first buffer given has been filled. So in this situation we may
have "lost" one sg buffer. It's the same for transmission.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-10-26 15:43:26 -04:00

2259 lines
56 KiB
C

/*
* 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 <linux/blkdev.h>
#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>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/mmc/host.h>
#include <linux/mmc/sdio.h>
#include <mach/atmel-mci.h>
#include <linux/atmel-mci.h>
#include <linux/atmel_pdc.h>
#include <asm/io.h>
#include <asm/unaligned.h>
#include <mach/cpu.h>
#include <mach/board.h>
#include "atmel-mci-regs.h"
#define ATMCI_DATA_ERROR_FLAGS (ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_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,
};
enum atmci_xfer_dir {
XFER_RECEIVE = 0,
XFER_TRANSMIT,
};
enum atmci_pdc_buf {
PDC_FIRST_BUF = 0,
PDC_SECOND_BUF,
};
struct atmel_mci_caps {
bool has_dma;
bool has_pdc;
bool has_cfg_reg;
bool has_cstor_reg;
bool has_highspeed;
bool has_rwproof;
};
struct atmel_mci_dma {
struct dma_chan *chan;
struct dma_async_tx_descriptor *data_desc;
};
/**
* 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 or PDC code.
* @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.
* @data_size: just data->blocks * data->blksz.
* @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.
* @cfg_reg: Value of the CFG 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.
* @caps: MCI capabilities depending on MCI version.
* @prepare_data: function to setup MCI before data transfer which
* depends on MCI capabilities.
* @submit_data: function to start data transfer which depends on MCI
* capabilities.
* @stop_transfer: function to stop data transfer which depends on MCI
* capabilities.
*
* 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 interrupt 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;
unsigned int data_size;
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;
u32 cfg_reg;
unsigned long bus_hz;
unsigned long mapbase;
struct clk *mck;
struct platform_device *pdev;
struct atmel_mci_slot *slot[ATMCI_MAX_NR_SLOTS];
struct atmel_mci_caps caps;
u32 (*prepare_data)(struct atmel_mci *host, struct mmc_data *data);
void (*submit_data)(struct atmel_mci *host, struct mmc_data *data);
void (*stop_transfer)(struct atmel_mci *host);
};
/**
* 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.
* @sdio_irq: SDIO irq mask for 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;
u32 sdio_irq;
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
#define ATMCI_SUSPENDED 3
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)
/*
* 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[3], 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[3], 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(ATMCI_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, ATMCI_REGS_SIZE);
clk_disable(host->mck);
spin_unlock_bh(&host->lock);
seq_printf(s, "MR:\t0x%08x%s%s CLKDIV=%u\n",
buf[ATMCI_MR / 4],
buf[ATMCI_MR / 4] & ATMCI_MR_RDPROOF ? " RDPROOF" : "",
buf[ATMCI_MR / 4] & ATMCI_MR_WRPROOF ? " WRPROOF" : "",
buf[ATMCI_MR / 4] & 0xff);
seq_printf(s, "DTOR:\t0x%08x\n", buf[ATMCI_DTOR / 4]);
seq_printf(s, "SDCR:\t0x%08x\n", buf[ATMCI_SDCR / 4]);
seq_printf(s, "ARGR:\t0x%08x\n", buf[ATMCI_ARGR / 4]);
seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n",
buf[ATMCI_BLKR / 4],
buf[ATMCI_BLKR / 4] & 0xffff,
(buf[ATMCI_BLKR / 4] >> 16) & 0xffff);
if (host->caps.has_cstor_reg)
seq_printf(s, "CSTOR:\t0x%08x\n", buf[ATMCI_CSTOR / 4]);
/* Don't read RSPR and RDR; it will consume the data there */
atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);
atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);
if (host->caps.has_dma) {
u32 val;
val = buf[ATMCI_DMA / 4];
seq_printf(s, "DMA:\t0x%08x OFFSET=%u CHKSIZE=%u%s\n",
val, val & 3,
((val >> 4) & 3) ?
1 << (((val >> 4) & 3) + 1) : 1,
val & ATMCI_DMAEN ? " DMAEN" : "");
}
if (host->caps.has_cfg_reg) {
u32 val;
val = buf[ATMCI_CFG / 4];
seq_printf(s, "CFG:\t0x%08x%s%s%s%s\n",
val,
val & ATMCI_CFG_FIFOMODE_1DATA ? " FIFOMODE_ONE_DATA" : "",
val & ATMCI_CFG_FERRCTRL_COR ? " FERRCTRL_CLEAR_ON_READ" : "",
val & ATMCI_CFG_HSMODE ? " HSMODE" : "",
val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
}
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 atmci_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 = atmci_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]);
atmci_writel(host, ATMCI_DTOR, (ATMCI_DTOMUL(dtomul) | ATMCI_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 = ATMCI_CMDR_CMDNB(cmd->opcode);
if (cmd->flags & MMC_RSP_PRESENT) {
if (cmd->flags & MMC_RSP_136)
cmdr |= ATMCI_CMDR_RSPTYP_136BIT;
else
cmdr |= ATMCI_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 |= ATMCI_CMDR_MAXLAT_64CYC;
if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
cmdr |= ATMCI_CMDR_OPDCMD;
data = cmd->data;
if (data) {
cmdr |= ATMCI_CMDR_START_XFER;
if (cmd->opcode == SD_IO_RW_EXTENDED) {
cmdr |= ATMCI_CMDR_SDIO_BLOCK;
} else {
if (data->flags & MMC_DATA_STREAM)
cmdr |= ATMCI_CMDR_STREAM;
else if (data->blocks > 1)
cmdr |= ATMCI_CMDR_MULTI_BLOCK;
else
cmdr |= ATMCI_CMDR_BLOCK;
}
if (data->flags & MMC_DATA_READ)
cmdr |= ATMCI_CMDR_TRDIR_READ;
}
return cmdr;
}
static void atmci_send_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);
atmci_writel(host, ATMCI_ARGR, cmd->arg);
atmci_writel(host, ATMCI_CMDR, cmd_flags);
}
static void atmci_send_stop_cmd(struct atmel_mci *host, struct mmc_data *data)
{
atmci_send_command(host, data->stop, host->stop_cmdr);
atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
}
/*
* Configure given PDC buffer taking care of alignement issues.
* Update host->data_size and host->sg.
*/
static void atmci_pdc_set_single_buf(struct atmel_mci *host,
enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
{
u32 pointer_reg, counter_reg;
if (dir == XFER_RECEIVE) {
pointer_reg = ATMEL_PDC_RPR;
counter_reg = ATMEL_PDC_RCR;
} else {
pointer_reg = ATMEL_PDC_TPR;
counter_reg = ATMEL_PDC_TCR;
}
if (buf_nb == PDC_SECOND_BUF) {
pointer_reg += ATMEL_PDC_SCND_BUF_OFF;
counter_reg += ATMEL_PDC_SCND_BUF_OFF;
}
atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
if (host->data_size <= sg_dma_len(host->sg)) {
if (host->data_size & 0x3) {
/* If size is different from modulo 4, transfer bytes */
atmci_writel(host, counter_reg, host->data_size);
atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCFBYTE);
} else {
/* Else transfer 32-bits words */
atmci_writel(host, counter_reg, host->data_size / 4);
}
host->data_size = 0;
} else {
/* We assume the size of a page is 32-bits aligned */
atmci_writel(host, counter_reg, sg_dma_len(host->sg) / 4);
host->data_size -= sg_dma_len(host->sg);
if (host->data_size)
host->sg = sg_next(host->sg);
}
}
/*
* Configure PDC buffer according to the data size ie configuring one or two
* buffers. Don't use this function if you want to configure only the second
* buffer. In this case, use atmci_pdc_set_single_buf.
*/
static void atmci_pdc_set_both_buf(struct atmel_mci *host, int dir)
{
atmci_pdc_set_single_buf(host, dir, PDC_FIRST_BUF);
if (host->data_size)
atmci_pdc_set_single_buf(host, dir, PDC_SECOND_BUF);
}
/*
* Unmap sg lists, called when transfer is finished.
*/
static void atmci_pdc_cleanup(struct atmel_mci *host)
{
struct mmc_data *data = host->data;
if (data)
dma_unmap_sg(&host->pdev->dev,
data->sg, data->sg_len,
((data->flags & MMC_DATA_WRITE)
? DMA_TO_DEVICE : DMA_FROM_DEVICE));
}
/*
* Disable PDC transfers. Update pending flags to EVENT_XFER_COMPLETE after
* having received ATMCI_TXBUFE or ATMCI_RXBUFF interrupt. Enable ATMCI_NOTBUSY
* interrupt needed for both transfer directions.
*/
static void atmci_pdc_complete(struct atmel_mci *host)
{
atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
atmci_pdc_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 (host->data) {
atmci_set_pending(host, EVENT_XFER_COMPLETE);
tasklet_schedule(&host->tasklet);
atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
}
}
static void atmci_dma_cleanup(struct atmel_mci *host)
{
struct mmc_data *data = host->data;
if (data)
dma_unmap_sg(host->dma.chan->device->dev,
data->sg, data->sg_len,
((data->flags & MMC_DATA_WRITE)
? DMA_TO_DEVICE : DMA_FROM_DEVICE));
}
/*
* 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");
if (host->caps.has_dma)
/* Disable DMA hardware handshaking on MCI */
atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
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.
*/
atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
}
}
/*
* Returns a mask of interrupt flags to be enabled after the whole
* request has been prepared.
*/
static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
{
u32 iflags;
data->error = -EINPROGRESS;
host->sg = data->sg;
host->data = data;
host->data_chan = NULL;
iflags = ATMCI_DATA_ERROR_FLAGS;
/*
* 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->pio_offset = 0;
if (data->flags & MMC_DATA_READ)
iflags |= ATMCI_RXRDY;
else
iflags |= ATMCI_TXRDY;
return iflags;
}
/*
* Set interrupt flags and set block length into the MCI mode register even
* if this value is also accessible in the MCI block register. It seems to be
* necessary before the High Speed MCI version. It also map sg and configure
* PDC registers.
*/
static u32
atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
{
u32 iflags, tmp;
unsigned int sg_len;
enum dma_data_direction dir;
data->error = -EINPROGRESS;
host->data = data;
host->sg = data->sg;
iflags = ATMCI_DATA_ERROR_FLAGS;
/* Enable pdc mode */
atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCMODE);
if (data->flags & MMC_DATA_READ) {
dir = DMA_FROM_DEVICE;
iflags |= ATMCI_ENDRX | ATMCI_RXBUFF;
} else {
dir = DMA_TO_DEVICE;
iflags |= ATMCI_ENDTX | ATMCI_TXBUFE;
}
/* Set BLKLEN */
tmp = atmci_readl(host, ATMCI_MR);
tmp &= 0x0000ffff;
tmp |= ATMCI_BLKLEN(data->blksz);
atmci_writel(host, ATMCI_MR, tmp);
/* Configure PDC */
host->data_size = data->blocks * data->blksz;
sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
if (host->data_size)
atmci_pdc_set_both_buf(host,
((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
return iflags;
}
static u32
atmci_prepare_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;
u32 iflags;
data->error = -EINPROGRESS;
WARN_ON(host->data);
host->sg = NULL;
host->data = data;
iflags = ATMCI_DATA_ERROR_FLAGS;
/*
* 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 atmci_prepare_data(host, data);
if (data->blksz & 3)
return atmci_prepare_data(host, data);
for_each_sg(data->sg, sg, data->sg_len, i) {
if (sg->offset & 3 || sg->length & 3)
return atmci_prepare_data(host, data);
}
/* 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 (host->caps.has_dma)
atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(3) | ATMCI_DMAEN);
if (data->flags & MMC_DATA_READ)
direction = DMA_FROM_DEVICE;
else
direction = DMA_TO_DEVICE;
sglen = dma_map_sg(chan->device->dev, data->sg,
data->sg_len, direction);
desc = chan->device->device_prep_slave_sg(chan,
data->sg, sglen, 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;
return iflags;
unmap_exit:
dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, direction);
return -ENOMEM;
}
static void
atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
{
return;
}
/*
* Start PDC according to transfer direction.
*/
static void
atmci_submit_data_pdc(struct atmel_mci *host, struct mmc_data *data)
{
if (data->flags & MMC_DATA_READ)
atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
else
atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
}
static void
atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data)
{
struct dma_chan *chan = host->data_chan;
struct dma_async_tx_descriptor *desc = host->dma.data_desc;
if (chan) {
dmaengine_submit(desc);
dma_async_issue_pending(chan);
}
}
static void atmci_stop_transfer(struct atmel_mci *host)
{
atmci_set_pending(host, EVENT_XFER_COMPLETE);
atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
}
/*
* Stop data transfer because error(s) occured.
*/
static void atmci_stop_transfer_pdc(struct atmel_mci *host)
{
atmci_set_pending(host, EVENT_XFER_COMPLETE);
atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
}
static void atmci_stop_transfer_dma(struct atmel_mci *host)
{
struct dma_chan *chan = host->data_chan;
if (chan) {
dmaengine_terminate_all(chan);
atmci_dma_cleanup(host);
} else {
/* Data transfer was stopped by the interrupt handler */
atmci_set_pending(host, EVENT_XFER_COMPLETE);
atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
}
}
/*
* Start a request: prepare data if needed, prepare the command and activate
* interrupts.
*/
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) {
atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
atmci_writel(host, ATMCI_MR, host->mode_reg);
if (host->caps.has_cfg_reg)
atmci_writel(host, ATMCI_CFG, host->cfg_reg);
host->need_reset = false;
}
atmci_writel(host, ATMCI_SDCR, slot->sdc_reg);
iflags = atmci_readl(host, ATMCI_IMR);
if (iflags & ~(ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
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) */
atmci_writel(host, ATMCI_CMDR, ATMCI_CMDR_SPCMD_INIT);
while (!(atmci_readl(host, ATMCI_SR) & ATMCI_CMDRDY))
cpu_relax();
}
iflags = 0;
data = mrq->data;
if (data) {
atmci_set_timeout(host, slot, data);
/* Must set block count/size before sending command */
atmci_writel(host, ATMCI_BLKR, ATMCI_BCNT(data->blocks)
| ATMCI_BLKLEN(data->blksz));
dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
ATMCI_BCNT(data->blocks) | ATMCI_BLKLEN(data->blksz));
iflags |= host->prepare_data(host, data);
}
iflags |= ATMCI_CMDRDY;
cmd = mrq->cmd;
cmdflags = atmci_prepare_command(slot->mmc, cmd);
atmci_send_command(host, cmd, cmdflags);
if (data)
host->submit_data(host, data);
if (mrq->stop) {
host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
host->stop_cmdr |= ATMCI_CMDR_STOP_XFER;
if (!(data->flags & MMC_DATA_WRITE))
host->stop_cmdr |= ATMCI_CMDR_TRDIR_READ;
if (data->flags & MMC_DATA_STREAM)
host->stop_cmdr |= ATMCI_CMDR_STREAM;
else
host->stop_cmdr |= ATMCI_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.)
*/
atmci_writel(host, ATMCI_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 &= ~ATMCI_SDCBUS_MASK;
switch (ios->bus_width) {
case MMC_BUS_WIDTH_1:
slot->sdc_reg |= ATMCI_SDCBUS_1BIT;
break;
case MMC_BUS_WIDTH_4:
slot->sdc_reg |= ATMCI_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);
atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
if (host->caps.has_cfg_reg)
atmci_writel(host, ATMCI_CFG, host->cfg_reg);
}
/*
* 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 < ATMCI_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 = ATMCI_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 (host->caps.has_rwproof)
host->mode_reg |= (ATMCI_MR_WRPROOF | ATMCI_MR_RDPROOF);
if (host->caps.has_cfg_reg) {
/* setup High Speed mode in relation with card capacity */
if (ios->timing == MMC_TIMING_SD_HS)
host->cfg_reg |= ATMCI_CFG_HSMODE;
else
host->cfg_reg &= ~ATMCI_CFG_HSMODE;
}
if (list_empty(&host->queue)) {
atmci_writel(host, ATMCI_MR, host->mode_reg);
if (host->caps.has_cfg_reg)
atmci_writel(host, ATMCI_CFG, host->cfg_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 < ATMCI_MAX_NR_SLOTS; i++) {
if (host->slot[i] && host->slot[i]->clock) {
any_slot_active = true;
break;
}
}
if (!any_slot_active) {
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
if (host->mode_reg) {
atmci_readl(host, ATMCI_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 void atmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
{
struct atmel_mci_slot *slot = mmc_priv(mmc);
struct atmel_mci *host = slot->host;
if (enable)
atmci_writel(host, ATMCI_IER, slot->sdio_irq);
else
atmci_writel(host, ATMCI_IDR, slot->sdio_irq);
}
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,
.enable_sdio_irq = atmci_enable_sdio_irq,
};
/* 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 transferring data.
*/
if (host->need_clock_update) {
atmci_writel(host, ATMCI_MR, host->mode_reg);
if (host->caps.has_cfg_reg)
atmci_writel(host, ATMCI_CFG, host->cfg_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] = atmci_readl(host, ATMCI_RSPR);
cmd->resp[1] = atmci_readl(host, ATMCI_RSPR);
cmd->resp[2] = atmci_readl(host, ATMCI_RSPR);
cmd->resp[3] = atmci_readl(host, ATMCI_RSPR);
if (status & ATMCI_RTOE)
cmd->error = -ETIMEDOUT;
else if ((cmd->flags & MMC_RSP_CRC) && (status & ATMCI_RCRCE))
cmd->error = -EILSEQ;
else if (status & (ATMCI_RINDE | ATMCI_RDIRE | ATMCI_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->stop_transfer(host);
host->data = NULL;
atmci_writel(host, ATMCI_IDR, ATMCI_NOTBUSY
| ATMCI_TXRDY | ATMCI_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.
*/
atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
atmci_writel(host, ATMCI_MR, host->mode_reg);
if (host->caps.has_cfg_reg)
atmci_writel(host, ATMCI_CFG, host->cfg_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;
host->stop_transfer(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,
atmci_readl(host, ATMCI_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)) {
host->stop_transfer(host);
if (data->stop)
atmci_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 & ATMCI_DTOE) {
dev_dbg(&host->pdev->dev,
"data timeout error\n");
data->error = -ETIMEDOUT;
} else if (status & ATMCI_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;
atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS);
}
if (!data->stop) {
atmci_request_end(host, host->mrq);
goto unlock;
}
prev_state = state = STATE_SENDING_STOP;
if (!data->error)
atmci_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 = atmci_readl(host, ATMCI_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 = atmci_readl(host, ATMCI_SR);
if (status & ATMCI_DATA_ERROR_FLAGS) {
atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_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 & ATMCI_RXRDY);
host->pio_offset = offset;
data->bytes_xfered += nbytes;
return;
done:
atmci_writel(host, ATMCI_IDR, ATMCI_RXRDY);
atmci_writel(host, ATMCI_IER, ATMCI_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));
atmci_writel(host, ATMCI_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) {
atmci_writel(host, ATMCI_TDR, value);
goto done;
}
offset = 4 - remaining;
buf = sg_virt(sg);
memcpy((u8 *)&value + remaining, buf, offset);
atmci_writel(host, ATMCI_TDR, value);
nbytes += offset;
}
status = atmci_readl(host, ATMCI_SR);
if (status & ATMCI_DATA_ERROR_FLAGS) {
atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_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 & ATMCI_TXRDY);
host->pio_offset = offset;
data->bytes_xfered += nbytes;
return;
done:
atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY);
atmci_writel(host, ATMCI_IER, ATMCI_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)
{
atmci_writel(host, ATMCI_IDR, ATMCI_CMDRDY);
host->cmd_status = status;
smp_wmb();
atmci_set_pending(host, EVENT_CMD_COMPLETE);
tasklet_schedule(&host->tasklet);
}
static void atmci_sdio_interrupt(struct atmel_mci *host, u32 status)
{
int i;
for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
struct atmel_mci_slot *slot = host->slot[i];
if (slot && (status & slot->sdio_irq)) {
mmc_signal_sdio_irq(slot->mmc);
}
}
}
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 = atmci_readl(host, ATMCI_SR);
mask = atmci_readl(host, ATMCI_IMR);
pending = status & mask;
if (!pending)
break;
if (pending & ATMCI_DATA_ERROR_FLAGS) {
atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS
| ATMCI_RXRDY | ATMCI_TXRDY);
pending &= atmci_readl(host, ATMCI_IMR);
host->data_status = status;
smp_wmb();
atmci_set_pending(host, EVENT_DATA_ERROR);
tasklet_schedule(&host->tasklet);
}
if (pending & ATMCI_TXBUFE) {
atmci_writel(host, ATMCI_IDR, ATMCI_TXBUFE);
atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
/*
* We can receive this interruption before having configured
* the second pdc buffer, so we need to reconfigure first and
* second buffers again
*/
if (host->data_size) {
atmci_pdc_set_both_buf(host, XFER_TRANSMIT);
atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
atmci_writel(host, ATMCI_IER, ATMCI_TXBUFE);
} else {
atmci_pdc_complete(host);
}
} else if (pending & ATMCI_ENDTX) {
atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
if (host->data_size) {
atmci_pdc_set_single_buf(host,
XFER_TRANSMIT, PDC_SECOND_BUF);
atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
}
}
if (pending & ATMCI_RXBUFF) {
atmci_writel(host, ATMCI_IDR, ATMCI_RXBUFF);
atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
/*
* We can receive this interruption before having configured
* the second pdc buffer, so we need to reconfigure first and
* second buffers again
*/
if (host->data_size) {
atmci_pdc_set_both_buf(host, XFER_RECEIVE);
atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
atmci_writel(host, ATMCI_IER, ATMCI_RXBUFF);
} else {
atmci_pdc_complete(host);
}
} else if (pending & ATMCI_ENDRX) {
atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
if (host->data_size) {
atmci_pdc_set_single_buf(host,
XFER_RECEIVE, PDC_SECOND_BUF);
atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
}
}
if (pending & ATMCI_NOTBUSY) {
atmci_writel(host, ATMCI_IDR,
ATMCI_DATA_ERROR_FLAGS | ATMCI_NOTBUSY);
if (!host->data_status)
host->data_status = status;
smp_wmb();
atmci_set_pending(host, EVENT_DATA_COMPLETE);
tasklet_schedule(&host->tasklet);
}
if (pending & ATMCI_RXRDY)
atmci_read_data_pio(host);
if (pending & ATMCI_TXRDY)
atmci_write_data_pio(host);
if (pending & ATMCI_CMDRDY)
atmci_cmd_interrupt(host, status);
if (pending & (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
atmci_sdio_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, u32 sdio_irq)
{
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;
slot->sdio_irq = sdio_irq;
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 (sdio_irq)
mmc->caps |= MMC_CAP_SDIO_IRQ;
if (host->caps.has_highspeed)
mmc->caps |= MMC_CAP_SD_HIGHSPEED;
if (slot_data->bus_width >= 4)
mmc->caps |= MMC_CAP_4_BIT_DATA;
mmc->max_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);
}
static bool atmci_filter(struct dma_chan *chan, void *slave)
{
struct mci_dma_data *sl = slave;
if (sl && find_slave_dev(sl) == chan->device->dev) {
chan->private = slave_data_ptr(sl);
return true;
} else {
return false;
}
}
static void atmci_configure_dma(struct atmel_mci *host)
{
struct mci_platform_data *pdata;
if (host == NULL)
return;
pdata = host->pdev->dev.platform_data;
if (pdata && find_slave_dev(pdata->dma_slave)) {
dma_cap_mask_t mask;
setup_dma_addr(pdata->dma_slave,
host->mapbase + ATMCI_TDR,
host->mapbase + ATMCI_RDR);
/* Try to grab a DMA channel */
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
host->dma.chan =
dma_request_channel(mask, atmci_filter, pdata->dma_slave);
}
if (!host->dma.chan)
dev_notice(&host->pdev->dev, "DMA not available, using PIO\n");
else
dev_info(&host->pdev->dev,
"Using %s for DMA transfers\n",
dma_chan_name(host->dma.chan));
}
static inline unsigned int atmci_get_version(struct atmel_mci *host)
{
return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
}
/*
* HSMCI (High Speed MCI) module is not fully compatible with MCI module.
* HSMCI provides DMA support and a new config register but no more supports
* PDC.
*/
static void __init atmci_get_cap(struct atmel_mci *host)
{
unsigned int version;
version = atmci_get_version(host);
dev_info(&host->pdev->dev,
"version: 0x%x\n", version);
host->caps.has_dma = 0;
host->caps.has_pdc = 0;
host->caps.has_cfg_reg = 0;
host->caps.has_cstor_reg = 0;
host->caps.has_highspeed = 0;
host->caps.has_rwproof = 0;
/* keep only major version number */
switch (version & 0xf00) {
case 0x100:
case 0x200:
host->caps.has_pdc = 1;
host->caps.has_rwproof = 1;
break;
case 0x300:
case 0x400:
case 0x500:
#ifdef CONFIG_AT_HDMAC
host->caps.has_dma = 1;
#else
host->caps.has_dma = 0;
dev_info(&host->pdev->dev,
"has dma capability but dma engine is not selected, then use pio\n");
#endif
host->caps.has_cfg_reg = 1;
host->caps.has_cstor_reg = 1;
host->caps.has_highspeed = 1;
host->caps.has_rwproof = 1;
break;
default:
dev_warn(&host->pdev->dev,
"Unmanaged mci version, set minimum capabilities\n");
break;
}
}
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, resource_size(regs));
if (!host->regs)
goto err_ioremap;
clk_enable(host->mck);
atmci_writel(host, ATMCI_CR, ATMCI_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;
/* Get MCI capabilities and set operations according to it */
atmci_get_cap(host);
if (host->caps.has_dma) {
dev_info(&pdev->dev, "using DMA\n");
host->prepare_data = &atmci_prepare_data_dma;
host->submit_data = &atmci_submit_data_dma;
host->stop_transfer = &atmci_stop_transfer_dma;
} else if (host->caps.has_pdc) {
dev_info(&pdev->dev, "using PDC\n");
host->prepare_data = &atmci_prepare_data_pdc;
host->submit_data = &atmci_submit_data_pdc;
host->stop_transfer = &atmci_stop_transfer_pdc;
} else {
dev_info(&pdev->dev, "no DMA, no PDC\n");
host->prepare_data = &atmci_prepare_data;
host->submit_data = &atmci_submit_data;
host->stop_transfer = &atmci_stop_transfer;
}
if (host->caps.has_dma)
atmci_configure_dma(host);
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],
0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
if (!ret)
nr_slots++;
}
if (pdata->slot[1].bus_width) {
ret = atmci_init_slot(host, &pdata->slot[1],
1, ATMCI_SDCSEL_SLOT_B, ATMCI_SDIOIRQB);
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:
if (host->dma.chan)
dma_release_channel(host->dma.chan);
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 < ATMCI_MAX_NR_SLOTS; i++) {
if (host->slot[i])
atmci_cleanup_slot(host->slot[i], i);
}
clk_enable(host->mck);
atmci_writel(host, ATMCI_IDR, ~0UL);
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
atmci_readl(host, ATMCI_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;
}
#ifdef CONFIG_PM
static int atmci_suspend(struct device *dev)
{
struct atmel_mci *host = dev_get_drvdata(dev);
int i;
for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
struct atmel_mci_slot *slot = host->slot[i];
int ret;
if (!slot)
continue;
ret = mmc_suspend_host(slot->mmc);
if (ret < 0) {
while (--i >= 0) {
slot = host->slot[i];
if (slot
&& test_bit(ATMCI_SUSPENDED, &slot->flags)) {
mmc_resume_host(host->slot[i]->mmc);
clear_bit(ATMCI_SUSPENDED, &slot->flags);
}
}
return ret;
} else {
set_bit(ATMCI_SUSPENDED, &slot->flags);
}
}
return 0;
}
static int atmci_resume(struct device *dev)
{
struct atmel_mci *host = dev_get_drvdata(dev);
int i;
int ret = 0;
for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
struct atmel_mci_slot *slot = host->slot[i];
int err;
slot = host->slot[i];
if (!slot)
continue;
if (!test_bit(ATMCI_SUSPENDED, &slot->flags))
continue;
err = mmc_resume_host(slot->mmc);
if (err < 0)
ret = err;
else
clear_bit(ATMCI_SUSPENDED, &slot->flags);
}
return ret;
}
static SIMPLE_DEV_PM_OPS(atmci_pm, atmci_suspend, atmci_resume);
#define ATMCI_PM_OPS (&atmci_pm)
#else
#define ATMCI_PM_OPS NULL
#endif
static struct platform_driver atmci_driver = {
.remove = __exit_p(atmci_remove),
.driver = {
.name = "atmel_mci",
.pm = ATMCI_PM_OPS,
},
};
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 (Atmel)");
MODULE_LICENSE("GPL v2");