diff options
Diffstat (limited to 'arch/arm/plat-mxc/dma_mx2.c')
| -rw-r--r-- | arch/arm/plat-mxc/dma_mx2.c | 1316 |
1 files changed, 1316 insertions, 0 deletions
diff --git a/arch/arm/plat-mxc/dma_mx2.c b/arch/arm/plat-mxc/dma_mx2.c new file mode 100644 index 000000000000..5a7e93b31d57 --- /dev/null +++ b/arch/arm/plat-mxc/dma_mx2.c @@ -0,0 +1,1316 @@ +/* + * Copyright 2004-2009 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +/* Front-end to the DMA handling. This handles the allocation/freeing + * of DMA channels, and provides a unified interface to the machines + * DMA facilities. + */ + +/*! + * @file plat-mxc/dma_mx2.c + * @brief This file contains functions for DMA API + * + * @ingroup DMA_MX27 + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/mman.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/clk.h> + +#include <linux/proc_fs.h> +#include <linux/io.h> + +#include <mach/hardware.h> +#include <mach/dma.h> +#include <asm/delay.h> + +#include <asm/atomic.h> + +/* commented temperily for mx27 compilation +#define DMA_PM +*/ +#ifdef DMA_PM +#include <linux/pm.h> +#include <mach/apmc.h> +struct apmc_user *dma_apmc_user; +struct pm_dev *dma_pm; +#define DMA_PMST_RESUME 0 +#define DMA_PMST_STANDBY 1 +#define DMA_PMST_SUSPEND 2 +static unsigned int dma_pm_status = DMA_PMST_RESUME; +#endif + +/*! + * This variable is used to controll the clock of DMA. + * It counts the number of actived channels + */ +static atomic_t g_dma_actived = ATOMIC_INIT(0); + +/*! + * This variable point a proc file which contains the information + * of DMA channels + */ +static struct proc_dir_entry *g_proc_dir; + +/*! + * The dma channels + */ +static mxc_dma_channel_t g_dma_channels[MAX_DMA_CHANNELS]; +static mx2_dma_priv_t g_dma_privates[MXC_DMA_CHANNELS]; +static mx2_dma_bd_t g_dma_bd_table[MXC_DMA_CHANNELS][MAX_BD_SIZE]; + +static DEFINE_SPINLOCK(dma_list_lock); + +static struct clk *dma_clk; + +/*!@brief flush buffer descriptor ring*/ +#define flush_dma_bd(private) \ + { \ + atomic_set(&(private->bd_used), 0); \ + private->bd_rd = private->bd_wr;\ + } + +/*!@brief get next buffer discriptor */ +#define next_dma_bd(private) \ + ({ \ + int bd_next = (private->bd_rd+1)%MAX_BD_SIZE; \ + (bd_next == private->bd_wr) ? NULL: private->bd_ring+bd_next;\ + }) + +static inline int consume_dma_bd(mxc_dma_channel_t * dma, int error); +/*! + *@brief allocate a dma channel. + * + *@param idx Requested channel NO. + * @li MXC_INVLAID_CHANNEL System allocates a free channel which is not statically allocated. + * @li Others User requests a specific channel + *@return @li MXC_INVLAID_CHANNEL Failure + * @li Others Success + */ +static inline int get_dma_channel(int idx) +{ + int i; + mxc_dma_channel_t *p; + + if ((idx >= MAX_DMA_CHANNELS) && (idx != MXC_DMA_DYNAMIC_CHANNEL)) { + return -1; + } + if (idx != MXC_DMA_DYNAMIC_CHANNEL) { + p = g_dma_channels + idx; + BUG_ON(p->dynamic != 0); + if (xchg(&p->lock, 1) != 0) { + return -1; + } + return idx; + } + + p = g_dma_channels; + for (i = 0; (i < MAX_DMA_CHANNELS); i++, p++) { + if (p->dynamic && (xchg(&p->lock, 1) == 0)) { + return i; + } + } + return -1; +} + +/*! + *@brief release a dma channel. + * + *@param idx channel number + *@return none; + */ +static inline void put_dma_channel(int idx) +{ + mxc_dma_channel_t *p; + + if ((idx < MAX_DMA_CHANNELS) && (idx >= 0)) { + p = g_dma_channels + idx; + (void)xchg(&p->lock, 0); + } +} + +/*! + *@brief Get dma list for /proc/dma + */ +static int mxc_get_dma_list(char *buf) +{ + mxc_dma_channel_t *dma; + char *p = buf; + int i; + + for (i = 0, dma = g_dma_channels; i < MAX_DMA_CHANNELS; i++, dma++) { + if (dma->lock) { + p += sprintf(p, "dma channel %2d: %s\n", i, + dma->dev_name ? dma->dev_name : "unknown"); + } else { + p += sprintf(p, "dma channel %2d: unused\n", i); + } + } + + return p - buf; +} + +/*!@brief save the mask of dma interrupts*/ +#define save_dma_interrupt(flags) \ + flags = __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DIMR) + +/*!@brief restore the mask of dma interrupts*/ +#define restore_dma_interrupt(flags) \ + __raw_writel(flags, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DIMR) + +/*!@brief disable interrupt of dma channel*/ +static inline void mask_dma_interrupt(int channel) +{ + unsigned long reg; + save_dma_interrupt(reg); + reg |= 1 << channel; /*mask interrupt; */ + restore_dma_interrupt(reg); +} + +/*!@brief enable interrupt of dma channel */ +static inline void unmask_dma_interrupt(int channel) +{ + unsigned long reg; + save_dma_interrupt(reg); + reg &= ~(1 << channel); /*unmask interrupt; */ + restore_dma_interrupt(reg); +} + +/*!@brief get interrupt event of dma channel */ +static unsigned long inline __get_dma_interrupt(int channel) +{ + unsigned long mode; + mode = 0; + if (__raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DISR) & (1 << channel)) + mode |= DMA_DONE; + + if (__raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DBTOSR) & + (1 << channel)) + mode |= DMA_BURST_TIMEOUT; + if (__raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DSESR) & (1 << channel)) + mode |= DMA_TRANSFER_ERROR; + + if (__raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DBOSR) & (1 << channel)) + mode |= DMA_BUFFER_OVERFLOW; + if (__raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DRTOSR) & + (1 << channel)) + mode |= DMA_REQUEST_TIMEOUT; + return mode; +} + +/*! + *@brief clean all event of dma interrupt and return the valid event. + */ +static unsigned long inline __clear_dma_interrupt(int channel) +{ + unsigned long mode; + mode = __get_dma_interrupt(channel); + __raw_writel(1 << channel, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DISR); + __raw_writel(1 << channel, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DBTOSR); + __raw_writel(1 << channel, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DRTOSR); + __raw_writel(1 << channel, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DSESR); + __raw_writel(1 << channel, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DBOSR); + + return mode; +} + +/*!@brief This function enables dma clocks without lock */ +static void inline __enable_dma_clk(void) +{ + unsigned long reg; + clk_enable(dma_clk); + reg = __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DCR); + reg |= 0x1; + __raw_writel(reg, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DCR); +} + +/*!@brief This function disables dma clocks without lock */ +static void inline __disable_dma_clk(void) +{ + unsigned long reg; + reg = __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DCR); + reg &= ~0x1; + __raw_writel(reg, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DCR); + clk_disable(dma_clk); +} + +/*!@brief This function enables dma clocks with lock */ +static void inline enable_dma_clk(void) +{ + unsigned long flags; + spin_lock_irqsave(&dma_list_lock, flags); + if (atomic_read(&g_dma_actived) == 0) { + __enable_dma_clk(); + } + spin_unlock_irqrestore(&dma_list_lock, flags); + return; +} + +/*!@brief This function disables dma clocks without locked */ +static void inline disable_dma_clk(void) +{ + unsigned long flags; + spin_lock_irqsave(&dma_list_lock, flags); + if (atomic_read(&g_dma_actived) == 0) { + __disable_dma_clk(); + } + spin_unlock_irqrestore(&dma_list_lock, flags); + return; +} + +/*!@brief select a buffer to transfer and + * setup dma channel for current transfer + */ +static void setup_dmac(mxc_dma_channel_t * dma) +{ + mx2_dma_priv_t *priv = (mx2_dma_priv_t *) dma->private; + dma_regs_t *dma_base = (dma_regs_t *) (priv->dma_base); + mx2_dma_bd_t *p, *q; + unsigned long ctrl_val; + + if (dma->active == 0) { + printk(KERN_ERR + "dma channel %d is not enabled, when receiving this channel 's interrupt\n", + dma->channel); + return; + } + if (atomic_read(&(priv->bd_used)) <= 0) { + printk(KERN_ERR "dma channel %d is empty\n", dma->channel); + dma->active = 0; + atomic_dec(&g_dma_actived); + return; + } + /* BUSY: transfering + * PEND: Wait for set to DMAC. + * s1: no transfering: + * set first(one BUSY). if there are more than one tranfer. set second &repeat is enabled(two BUSY). + * + * s2: transfering & just on transfer + * one BUSY. set the tranesfer and set repeat bit(two BUSY) + * s3: transfering & repeat has set + * has two BUSY. + */ + p = priv->bd_ring + priv->bd_rd; + q = next_dma_bd(priv); + if (!(p->state & DMA_BD_ST_BUSY)) { + /*NOTICE:: This is first buffer or dma chain does not support chain-buffer. So CEN must clear & set again */ + ctrl_val = + __raw_readl(&(dma_base->Ctl)) & + (~(DMA_CTL_ACRPT | DMA_CTL_RPT | DMA_CTL_CEN)); + __raw_writel(ctrl_val, &(dma_base->Ctl)); + if (p->mode != dma->mode) { + dma->mode = p->mode; /* bi-dir channel do mode change */ + if (dma->mode == MXC_DMA_MODE_READ) { + DMA_CTL_SET_SMOD(ctrl_val, + priv->dma_info->sourceType); + DMA_CTL_SET_SSIZ(ctrl_val, + priv->dma_info->sourcePort); + DMA_CTL_SET_DMOD(ctrl_val, + priv->dma_info->destType); + DMA_CTL_SET_DSIZ(ctrl_val, + priv->dma_info->destPort); + } else { + DMA_CTL_SET_SMOD(ctrl_val, + priv->dma_info->destType); + DMA_CTL_SET_SSIZ(ctrl_val, + priv->dma_info->destPort); + DMA_CTL_SET_DMOD(ctrl_val, + priv->dma_info->sourceType); + DMA_CTL_SET_DSIZ(ctrl_val, + priv->dma_info->sourcePort); + } + } + __raw_writel(p->src_addr, &(dma_base->SourceAddr)); + __raw_writel(p->dst_addr, &(dma_base->DestAddr)); + __raw_writel(p->count, &(dma_base->Count)); + p->state |= DMA_BD_ST_BUSY; + p->state &= ~(DMA_BD_ST_PEND); + ctrl_val |= DMA_CTL_CEN; + __raw_writel(ctrl_val, &(dma_base->Ctl)); + if (q && priv->dma_chaining) { /*DO chain-buffer */ + __raw_writel(q->src_addr, &(dma_base->SourceAddr)); + __raw_writel(q->dst_addr, &(dma_base->DestAddr)); + __raw_writel(q->count, &(dma_base->Count)); + q->state |= DMA_BD_ST_BUSY; + q->state &= ~(DMA_BD_ST_PEND); + ctrl_val |= DMA_CTL_ACRPT | DMA_CTL_RPT | DMA_CTL_CEN; + __raw_writel(ctrl_val, &(dma_base->Ctl)); + } + } else { /* Just dma channel which supports dma buffer can run to there */ + BUG_ON(!priv->dma_chaining); + if (q) { /* p is tranfering, then q must be set into dma controller */ + /*WARNING:: [1] dangerous area begin. + * If the p is completed during MCU run in this erea, the dma channel is crashed. + */ + __raw_writel(q->src_addr, &(dma_base->SourceAddr)); + __raw_writel(q->dst_addr, &(dma_base->DestAddr)); + __raw_writel(q->count, &(dma_base->Count)); + /*WARNING:: [2] dangerous area end */ + ctrl_val = + __raw_readl(&(dma_base->Ctl)) | (DMA_CTL_ACRPT | + DMA_CTL_RPT | + DMA_CTL_CEN); + __raw_writel(ctrl_val, &(dma_base->Ctl)); + + /* WARNING:: This is workaround and it is dangerous: + * the judgement is not safety. + */ + if (!__get_dma_interrupt(dma->channel)) { + q->state |= DMA_BD_ST_BUSY; + q->state &= ~(DMA_BD_ST_PEND); + } else { + /*Waiting re-enable is in ISR */ + printk(KERN_ERR + "Warning:: The privous transfer is completed. Maybe the chain buffer is stopped."); + } + } else { /* Last buffer is transfering: just clear RPT bit */ + ctrl_val = + __raw_readl(&(dma_base->Ctl)) & + (~(DMA_CTL_ACRPT | DMA_CTL_RPT)); + __raw_writel(ctrl_val, &(dma_base->Ctl)); + } + } +} + +/*! + * @brief interrupt handler of dma channel + */ +static irqreturn_t dma_irq_handler(int irq, void *dev_id) +{ + mxc_dma_channel_t *dma = (mxc_dma_channel_t *) dev_id; + mx2_dma_priv_t *priv = (mx2_dma_priv_t *) (dma ? dma->private : NULL); + dma_regs_t *dma_base; + int state, error = MXC_DMA_DONE; + + BUG_ON(priv == NULL); + + dma_base = (dma_regs_t *) priv->dma_base; + + state = __clear_dma_interrupt(dma->channel); + + priv->trans_bytes += dma_base->transferd; + if (state != DMA_DONE) { + if (state & DMA_REQUEST_TIMEOUT) { + error = MXC_DMA_REQUEST_TIMEOUT; + } else { + error = MXC_DMA_TRANSFER_ERROR; + } + } + if (consume_dma_bd(dma, error)) { + disable_dma_clk(); + if (dma->cb_fn) { + dma->cb_fn(dma->cb_args, error, priv->trans_bytes); + } + priv->trans_bytes = 0; + } else { + disable_dma_clk(); + } + return IRQ_HANDLED; +} + +/*! + *@brief Set DMA channel parameters + * + *@param dma Requested channel NO. + *@param dma_info Channel configuration + *@return @li 0 Success + * @li others Failure + */ +static int setup_dma_channel(mxc_dma_channel_t * dma, mx2_dma_info_t * dma_info) +{ + mx2_dma_priv_t *priv = (mx2_dma_priv_t *) (dma ? dma->private : NULL); + dma_regs_t *dma_base; + unsigned long reg; + + if (!dma_info || !priv) { + return -1; + } + + if (dma_info->sourceType > 3) { + return -1; + } + if (dma_info->destType > 3) { + return -1; + } + if (dma_info->destPort > 3) { + return -1; + } + if (dma_info->sourcePort > 3) { + return -1; + } + if (dma_info->M2D_Valid) { + /*add for second dma */ + if (dma_info->W < dma_info->X) { + return -1; + } + } + + priv->dma_chaining = dma_info->dma_chaining; + priv->ren = dma_info->ren; + + if (dma_info->sourceType != DMA_TYPE_FIFO + && dma_info->destType != DMA_TYPE_FIFO) { + if (dma_info->ren) { + printk(KERN_INFO + "Warning:request enable just affect source or destination port is FIFO !\n"); + priv->ren = 0; + } + } + + if (dma_info->M2D_Valid) { + if (dma_info->msel) { + __raw_writel(dma_info->W, + IO_ADDRESS(DMA_BASE_ADDR) + DMA_WSRB); + __raw_writel(dma_info->X, + IO_ADDRESS(DMA_BASE_ADDR) + DMA_XSRB); + __raw_writel(dma_info->Y, + IO_ADDRESS(DMA_BASE_ADDR) + DMA_YSRB); + + } else { + __raw_writel(dma_info->W, + IO_ADDRESS(DMA_BASE_ADDR) + DMA_WSRA); + __raw_writel(dma_info->X, + IO_ADDRESS(DMA_BASE_ADDR) + DMA_XSRA); + __raw_writel(dma_info->Y, + IO_ADDRESS(DMA_BASE_ADDR) + DMA_YSRA); + } + } + + dma_base = (dma_regs_t *) (priv->dma_base); + + __raw_writel(dma_info->burstLength, &(dma_base->BurstLength)); + __raw_writel(dma_info->request, &(dma_base->RequestSource)); + + if (dma_info->ren) { + reg = dma_info->busuntils & 0x1FFFF; + if (dma_info->rto_en) { + reg |= 0xE000; + } + __raw_writel(reg, &(dma_base->BusUtilt)); + } else { + __raw_writel(dma_info->busuntils, &(dma_base->BusUtilt)); + } + + reg = __raw_readl(&(dma_base->Ctl)) & (~(DMA_CTL_ACRPT | DMA_CTL_RPT)); + + if (dma_info->dir) { + reg |= DMA_CTL_MDIR; + } else { + reg &= ~DMA_CTL_MDIR; + } + + if (priv->ren) { + reg |= DMA_CTL_REN; + } else { + reg &= ~DMA_CTL_REN; + } + + if ((dma_info->M2D_Valid) && (dma_info->msel)) { + reg |= DMA_CTL_MSEL; + } else { + reg &= ~DMA_CTL_MSEL; + } + + if (dma_info->mode) { + DMA_CTL_SET_SMOD(reg, dma_info->destType); + DMA_CTL_SET_SSIZ(reg, dma_info->destPort); + DMA_CTL_SET_DMOD(reg, dma_info->sourceType); + DMA_CTL_SET_DSIZ(reg, dma_info->sourcePort); + } else { + DMA_CTL_SET_SMOD(reg, dma_info->sourceType); + DMA_CTL_SET_SSIZ(reg, dma_info->sourcePort); + DMA_CTL_SET_DMOD(reg, dma_info->destType); + DMA_CTL_SET_DSIZ(reg, dma_info->destPort); + } + + __raw_writel(reg, &(dma_base->Ctl)); + + __clear_dma_interrupt(dma->channel); + unmask_dma_interrupt(dma->channel); + + disable_dma_clk(); + return 0; +} + +/*!@brief setup interrupt and setup dma channel by dma parameter */ +static inline int __init_dma_channel(mxc_dma_channel_t * chan, + mx2_dma_info_t * dma_info) +{ + mx2_dma_priv_t *dma_private = (mx2_dma_priv_t *) chan->private; + dma_regs_t *dma_base; + int ret; + + mask_dma_interrupt(chan->channel); + ret = + request_irq(dma_private->dma_irq, dma_irq_handler, + IRQF_DISABLED | IRQF_SHARED, chan->dev_name, + (void *)chan); + if (ret) { + printk(KERN_ERR + "%s: unable to request IRQ %d for DMA channel\n", + chan->dev_name, dma_private->dma_irq); + return ret; + } + + enable_dma_clk(); + + dma_base = (dma_regs_t *) (dma_private->dma_base); + __raw_writel(0, &(dma_base->Ctl)); + + ret = 0; + if ((ret = setup_dma_channel(chan, dma_info))) { + free_irq(dma_private->dma_irq, (void *)chan); + } + disable_dma_clk(); + return 0; +} + +/*!@brief initialize buffer descriptor ring.*/ +static inline void init_dma_bd(mx2_dma_priv_t * private) +{ + int i; + mx2_dma_bd_t *pbd; + private->bd_rd = private->bd_wr = 0; + atomic_set(&(private->bd_used), 0); + for (i = 0, pbd = private->bd_ring; i < MAX_BD_SIZE; i++, pbd++) { + pbd->state = 0; + } +} + +/*!@brief add dma buffer into buffer descriptor ring */ +static inline int fill_dma_bd(mxc_dma_channel_t * dma, + mxc_dma_requestbuf_t * buf, int num, + mxc_dma_mode_t mode) +{ + int i, wr; + unsigned long flags, mask; + mx2_dma_priv_t *priv = dma->private; + mx2_dma_bd_t *p, *q; + + if ((atomic_read(&(priv->bd_used)) + num) > MAX_BD_SIZE) { + return -EBUSY; + } + + for (i = 0; i < num; i++) { + wr = priv->bd_wr; + p = priv->bd_ring + wr; + p->mode = mode; + p->count = buf[i].num_of_bytes; + p->src_addr = buf[i].src_addr; + p->dst_addr = buf[i].dst_addr; + if (i == num - 1) { + p->state = DMA_BD_ST_LAST | DMA_BD_ST_PEND; + } else { + p->state = DMA_BD_ST_PEND; + } + priv->bd_wr = (wr + 1) % MAX_BD_SIZE; + atomic_inc(&(priv->bd_used)); + + if (atomic_read(&(priv->bd_used)) != 2) + continue; + /* Disable interrupt of this channel */ + local_irq_save(flags); + local_irq_disable(); + save_dma_interrupt(mask); + mask_dma_interrupt(dma->channel); + local_irq_restore(flags); + /*TODO :: + * If channel is transfering and supports chain_buffer, + * when the new buffer is 2st buffer , repeat must be enabled + */ + if (priv->dma_chaining && dma->active) { + q = priv->bd_ring + priv->bd_rd; + if (q && (q->state & DMA_BD_ST_BUSY)) { + if (atomic_read(&(priv->bd_used)) == 2) { + setup_dmac(dma); + } + } + } + restore_dma_interrupt(mask); + } + return 0; +} + +/*!@brief add sg-list into buffer descriptor ring */ +static inline int fill_dma_bd_by_sg(mxc_dma_channel_t * dma, + struct scatterlist *sg, int num, + int real_bytes, mxc_dma_mode_t mode) +{ + int i, wr, total_bytes = real_bytes; + unsigned long flags, mask; + mx2_dma_priv_t *priv = dma->private; + mx2_dma_bd_t *p, *q; + if ((atomic_read(&(priv->bd_used)) + num) > MAX_BD_SIZE) { + return -EBUSY; + } + + for (i = 0; i < num && ((real_bytes <= 0) || (total_bytes > 0)); i++) { + wr = priv->bd_wr; + p = priv->bd_ring + wr; + p->mode = mode; + if (real_bytes > 0) { + if (sg[i].length >= total_bytes) { + p->count = total_bytes; + } else { + p->count = sg[i].length; + } + total_bytes -= p->count; + } else { + p->count = sg[i].length; + } + if (mode == MXC_DMA_MODE_READ) { + p->src_addr = priv->dma_info->per_address; + p->dst_addr = sg[i].dma_address; + } else { + p->dst_addr = priv->dma_info->per_address; + p->src_addr = sg[i].dma_address; + } + if ((i == num - 1) || ((real_bytes > 0) && (total_bytes == 0))) { + p->state = DMA_BD_ST_LAST | DMA_BD_ST_PEND; + } else { + p->state = DMA_BD_ST_PEND; + } + priv->bd_wr = (wr + 1) % MAX_BD_SIZE; + atomic_inc(&(priv->bd_used)); + + if (atomic_read(&(priv->bd_used)) != 2) + continue; + /* Disable interrupt of this channel */ + local_irq_save(flags); + local_irq_disable(); + save_dma_interrupt(mask); + mask_dma_interrupt(dma->channel); + local_irq_restore(flags); + /*TODO :: + * If channel is transfering and supports chain_buffer, + * when the new buffer is 2st buffer , repeat must be enabled + */ + if (priv->dma_chaining && dma->active) { + q = next_dma_bd(priv); + if (q && (q->state & DMA_BD_ST_BUSY)) { + if ((atomic_read(&(priv->bd_used))) == 2) { + setup_dmac(dma); + } + } + } + restore_dma_interrupt(mask); + } + return 0; +} + +/*!@brief select next buffer descripter to transfer. + * return 1: need call call-back function. 0: Not need call call-back. + * it just is called in ISR + */ +static inline int consume_dma_bd(mxc_dma_channel_t * dma, int error) +{ + mx2_dma_priv_t *priv = dma->private; + mx2_dma_bd_t *p; + int notify = 0; + if (priv == NULL) { + printk(KERN_ERR + "request dma channel %d which is not initialize completed.!\n", + dma->channel); + return 1; + } + if (error != MXC_DMA_DONE) { + for (p = priv->bd_ring + priv->bd_rd; + atomic_read(&(priv->bd_used)) > 0;) { + priv->bd_rd = (priv->bd_rd + 1) % MAX_BD_SIZE; + atomic_dec(&(priv->bd_used)); + if (p->state & DMA_BD_ST_LAST) { + p->state = 0; + break; + } + p->state = 0; + } + notify = 1; + } else { + p = priv->bd_ring + priv->bd_rd; + priv->bd_rd = (priv->bd_rd + 1) % MAX_BD_SIZE; + atomic_dec(&(priv->bd_used)); + notify = (p->state & DMA_BD_ST_LAST) == DMA_BD_ST_LAST; + } + if (atomic_read(&(priv->bd_used)) <= 0) { + dma->active = 0; + atomic_dec(&g_dma_actived); + } else { + setup_dmac(dma); + } + return notify; +} + +/*! + * This function is generally called by the driver at open time. + * The DMA driver would do any initialization steps that is required + * to get the channel ready for data transfer. + * + * @param channel_id a pre-defined id. The peripheral driver would specify + * the id associated with its peripheral. This would be + * used by the DMA driver to identify the peripheral + * requesting DMA and do the necessary setup on the + * channel associated with the particular peripheral. + * The DMA driver could use static or dynamic DMA channel + * allocation. + * @param dev_name module name or device name + * @return returns a negative number on error if request for a DMA channel did not + * succeed, returns the channel number to be used on success. + */ +int mxc_dma_request_ext(mxc_dma_device_t channel_id, char *dev_name, + struct dma_channel_info *info) +{ + mxc_dma_channel_t *dma; + mx2_dma_priv_t *dma_private = NULL; + mx2_dma_info_t *dma_info = mxc_dma_get_info(channel_id); + int index; + int ret; + + if (dma_info == NULL) { + return -EINVAL; + } + + if ((index = get_dma_channel(dma_info->dma_chan)) < 0) { + return -ENODEV; + } + + dma = g_dma_channels + index; + dma_private = (mx2_dma_priv_t *) dma->private; + if (dma_private == NULL) { + printk(KERN_ERR + "request dma channel %d which is not initialize completed.!\n", + index); + ret = -EFAULT; + goto exit; + } + + dma->active = 0; + dma_private->dma_info = NULL; + dma->cb_fn = NULL; + dma->cb_args = NULL; + dma->dev_name = dev_name; + dma->mode = dma_info->mode ? MXC_DMA_MODE_WRITE : MXC_DMA_MODE_READ; + init_dma_bd(dma_private); + + if (!(ret = __init_dma_channel(dma, dma_info))) { + dma_private->dma_info = dma_info; + return index; + } + exit: + put_dma_channel(index); + return ret; +} + +/*! + * This function is generally called by the driver at close time. The DMA + * driver would do any cleanup associated with this channel. + * + * @param channel_num the channel number returned at request time. This + * would be used by the DMA driver to identify the calling + * driver and do the necessary cleanup on the channel + * associated with the particular peripheral + * @return returns a negative number on error or 0 on success + */ +int mxc_dma_free(int channel_num) +{ + mxc_dma_channel_t *dma; + mx2_dma_priv_t *dma_private; + + if ((channel_num >= MAX_DMA_CHANNELS) || (channel_num < 0)) { + return -EINVAL; + } + + dma = g_dma_channels + channel_num; + dma_private = (mx2_dma_priv_t *) dma->private; + if (dma_private == NULL) { + printk(KERN_ERR + "Free dma %d which is not completed initialization \n", + channel_num); + return -EFAULT; + } + if (dma->lock) { + if (dma->active) { /*Channel is busy */ + mxc_dma_disable(channel_num); + } + + dma_private = (mx2_dma_priv_t *) dma->private; + + enable_dma_clk(); + mask_dma_interrupt(channel_num); + disable_dma_clk(); + + free_irq(dma_private->dma_irq, (void *)dma); + put_dma_channel(channel_num); + } + return 0; +} + +/*! + * This function would just configure the buffers specified by the user into + * dma channel. The caller must call mxc_dma_enable to start this transfer. + * + * @param channel_num the channel number returned at request time. This + * would be used by the DMA driver to identify the calling + * driver and do the necessary cleanup on the channel + * associated with the particular peripheral + * @param dma_buf an array of physical addresses to the user defined + * buffers. The caller must guarantee the dma_buf is + * available until the transfer is completed. + * @param num_buf number of buffers in the array + * @param mode specifies whether this is READ or WRITE operation + * @return This function returns a negative number on error if buffer could not be + * added with DMA for transfer. On Success, it returns 0 + */ +int mxc_dma_config(int channel_num, mxc_dma_requestbuf_t * dma_buf, int num_buf, + mxc_dma_mode_t mode) +{ + mxc_dma_channel_t *dma; + mx2_dma_priv_t *dma_private; + + if ((dma_buf == NULL) || (num_buf < 1)) { + return -EINVAL; + } + + if ((channel_num >= MAX_DMA_CHANNELS) || (channel_num < 0)) { + return -EINVAL; + } + + dma = g_dma_channels + channel_num; + dma_private = (mx2_dma_priv_t *) dma->private; + if (dma_private == NULL) { + printk(KERN_ERR + "config dma %d which is not completed initialization \n", + channel_num); + return -EFAULT; + } + + if (dma->lock == 0) { + return -ENODEV; + } + + /*TODO: dma chainning can not support on bi-dir channel */ + if (dma_private->dma_chaining && (dma->mode != mode)) { + return -EINVAL; + } + + /*TODO: fill dma buffer into driver . + * If driver is no enought buffer to save them , it will return -EBUSY + */ + if (fill_dma_bd(dma, dma_buf, num_buf, mode)) { + return -EBUSY; + } + + return 0; +} + +/*! + * This function would just configure the scatterlist specified by the + * user into dma channel. This is a slight variation of mxc_dma_config(), + * it is provided for the convenience of drivers that have a scatterlist + * passed into them. It is the calling driver's responsibility to have the + * correct physical address filled in the "dma_address" field of the + * scatterlist. + * + * @param channel_num the channel number returned at request time. This + * would be used by the DMA driver to identify the calling + * driver and do the necessary cleanup on the channel + * associated with the particular peripheral + * @param sg a scatterlist of buffers. The caller must guarantee + * the dma_buf is available until the transfer is + * completed. + * @param num_buf number of buffers in the array + * @param num_of_bytes total number of bytes to transfer. If set to 0, this + * would imply to use the length field of the scatterlist + * for each DMA transfer. Else it would calculate the size + * for each DMA transfer. + * @param mode specifies whether this is READ or WRITE operation + * @return This function returns a negative number on error if buffer could not + * be added with DMA for transfer. On Success, it returns 0 + */ +int mxc_dma_sg_config(int channel_num, struct scatterlist *sg, + int num_buf, int num_of_bytes, mxc_dma_mode_t mode) +{ + mxc_dma_channel_t *dma; + mx2_dma_priv_t *dma_private; + + if ((sg == NULL) || (num_buf < 1) || (num_of_bytes < 0)) { + return -EINVAL; + } + + if ((channel_num >= MAX_DMA_CHANNELS) || (channel_num < 0)) { + return -EINVAL; + } + + dma = g_dma_channels + channel_num; + dma_private = (mx2_dma_priv_t *) dma->private; + if (dma_private == NULL) { + printk(KERN_ERR + "config_sg dma %d which is not completed initialization \n", + channel_num); + return -EFAULT; + } + + if (dma->lock == 0) { + return -ENODEV; + } + + /*TODO: dma chainning can not support on bi-dir channel */ + if (dma_private->dma_chaining && (dma->mode != mode)) { + return -EINVAL; + } + + /*TODO: fill dma buffer into driver . + * If driver is no enought buffer to save them , it will return -EBUSY + */ + if (fill_dma_bd_by_sg(dma, sg, num_buf, num_of_bytes, mode)) { + return -EBUSY; + } + return 0; +} + +/*! + * This function is provided if the driver would like to set/change its + * callback function. + * + * @param channel_num the channel number returned at request time. This + * would be used by the DMA driver to identify the calling + * driver and do the necessary cleanup on the channel + * associated with the particular peripheral + * @param callback a callback function to provide notification on transfer + * completion, user could specify NULL if he does not wish + * to be notified + * @param arg an argument that gets passed in to the callback + * function, used by the user to do any driver specific + * operations. + * @return this function returns an error if the callback could not be set + * for the channel + */ +int mxc_dma_callback_set(int channel_num, mxc_dma_callback_t callback, + void *arg) +{ + mxc_dma_channel_t *dma; + + if ((channel_num >= MAX_DMA_CHANNELS) || (channel_num < 0)) { + return -EINVAL; + } + dma = g_dma_channels + channel_num; + + if (!dma->lock) { + return -ENODEV; + } + + if (dma->active) { + return -EBUSY; + } + dma->cb_fn = callback; + dma->cb_args = arg; + return 0; + +} + +/*! + * This stops the DMA channel and any ongoing transfers. Subsequent use of + * mxc_dma_enable() will restart the channel and restart the transfer. + * + * @param channel_num the channel number returned at request time. This + * would be used by the DMA driver to identify the calling + * driver and do the necessary cleanup on the channel + * associated with the particular peripheral + * @return returns a negative number on error or 0 on success + */ +int mxc_dma_disable(int channel_num) +{ + mxc_dma_channel_t *dma; + mx2_dma_priv_t *priv; + unsigned long ctrl_val; + + if ((channel_num >= MAX_DMA_CHANNELS) || (channel_num < 0)) { + return -EINVAL; + } + + dma = g_dma_channels + channel_num; + + if (dma->lock == 0) { + return -EINVAL; + } + + if (!dma->active) { + return -EINVAL; + } + + priv = (mx2_dma_priv_t *) dma->private; + if (priv == NULL) { + printk(KERN_ERR "disable a uncompleted dma channel %d\n", + channel_num); + return -EFAULT; + } + + dma->active = 0; + enable_dma_clk(); + + __clear_dma_interrupt(channel_num); + ctrl_val = + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_CCR(channel_num)); + ctrl_val &= ~DMA_CTL_CEN; /* clear CEN bit */ + __raw_writel(ctrl_val, + IO_ADDRESS(DMA_BASE_ADDR) + DMA_CCR(channel_num)); + disable_dma_clk(); + atomic_dec(&g_dma_actived); + + /*TODO: Clear all request buffers */ + flush_dma_bd(priv); + return 0; +} + +/*! + * This starts DMA transfer. Or it restarts DMA on a stopped channel + * previously stopped with mxc_dma_disable(). + * + * @param channel_num the channel number returned at request time. This + * would be used by the DMA driver to identify the calling + * driver and do the necessary cleanup on the channel + * associated with the particular peripheral + * @return returns a negative number on error or 0 on success + */ +int mxc_dma_enable(int channel_num) +{ + mxc_dma_channel_t *dma; + mx2_dma_priv_t *priv; + + if ((channel_num >= MAX_DMA_CHANNELS) || (channel_num < 0)) { + return -EINVAL; + } + + dma = g_dma_channels + channel_num; + + if (dma->lock == 0) { + return -EINVAL; + } + + priv = (mx2_dma_priv_t *) dma->private; + if (priv == NULL) { + printk(KERN_ERR "enable a uncompleted dma channel %d\n", + channel_num); + return -EFAULT; + } + + if (dma->active) { + return 0; + } + dma->active = 1; + priv->trans_bytes = 0; + + enable_dma_clk(); + + atomic_inc(&g_dma_actived); + __clear_dma_interrupt(channel_num); + + setup_dmac(dma); + disable_dma_clk(); + return 0; +} + +/*! +*@brief Dump DMA registers +* +*@param channel Requested channel NO. +*@return none +*/ + +void mxc_dump_dma_register(int channel) +{ + mxc_dma_channel_t *dma = &g_dma_channels[channel]; + mx2_dma_priv_t *priv = (mx2_dma_priv_t *) dma->private; + dma_regs_t *dma_base; + + printk(KERN_INFO "======== Dump dma channel %d \n", channel); + if ((unsigned)channel >= MXC_DMA_CHANNELS) { + printk(KERN_INFO "Channel number is invalid \n"); + return; + } + if (!dma->lock) { + printk(KERN_INFO "Channel is not allocated \n"); + return; + } + + printk(KERN_INFO "g_dma_actived = %d\n", atomic_read(&g_dma_actived)); + + enable_dma_clk(); + dma_base = (dma_regs_t *) (priv->dma_base); + printk(KERN_INFO "DMA COMMON REGISTER\n"); + printk(KERN_INFO "DMA CONTROL DMA_DCR: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DCR)); + printk(KERN_INFO "DMA Interrupt status DMA_DISR: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DISR)); + printk(KERN_INFO "DMA Interrupt Mask DMA_DIMR: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DIMR)); + printk(KERN_INFO "DMA Burst Time Out DMA_DBTOSR: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DBTOSR)); + printk(KERN_INFO "DMA request Time Out DMA_DRTOSR: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DRTOSR)); + printk(KERN_INFO "DMA Transfer Error DMA_DSESR: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DSESR)); + printk(KERN_INFO "DMA DMA_Overflow DMA_DBOSR: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DBOSR)); + printk(KERN_INFO "DMA Burst Time OutCtl DMA_BurstTOCtl: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_DBTOCR)); + + printk(KERN_INFO "DMA 2D X size: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_XSRA)); + printk(KERN_INFO "DMA 2D Y size: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_YSRA)); + printk(KERN_INFO "DMA 2D Z size: %08x\n", + __raw_readl(IO_ADDRESS(DMA_BASE_ADDR) + DMA_WSRA)); + + printk(KERN_INFO "DMA Chan %2d Sourc SourceAddr: %08x\n", channel, + __raw_readl(&(dma_base->SourceAddr))); + printk(KERN_INFO "DMA Chan %2d dest DestAddr: %08x\n", channel, + __raw_readl(&(dma_base->DestAddr))); + printk(KERN_INFO "DMA Chan %2d count Count: %08x\n", channel, + __raw_readl(&(dma_base->Count))); + printk(KERN_INFO "DMA Chan %2d Ctl Ctl: %08x\n", channel, + __raw_readl(&(dma_base->Ctl))); + printk(KERN_INFO "DMA Chan %2d request RequestSource: %08x\n", + channel, __raw_readl(&(dma_base->RequestSource))); + printk(KERN_INFO "DMA Chan %2d burstL BurstLength: %08x\n", channel, + __raw_readl(&(dma_base->BurstLength))); + printk(KERN_INFO "DMA Chan %2d requestTO ReqTimeout: %08x\n", channel, + __raw_readl(&(dma_base->ReqTimeout))); + printk(KERN_INFO "DMA Chan %2d BusUtilt BusUtilt: %08x\n", channel, + __raw_readl(&(dma_base->BusUtilt))); + + disable_dma_clk(); +} + +#ifdef DMA_PM + +static int channel_in_use(void) +{ + int i; + for (i = 0; i < MXC_DMA_CHANNELS; i++) { + if (dma_chan[i].lock) + return 1; + } + return 0; +} + +int mxc_dma_pm_standby(void) +{ + unsigned long reg; + if (dma_pm_status == DMA_PMST_STANDBY) + return 0; + + if (!channel_in_use()) { + /*Disable DMA */ + __disable_dma_clk(); + dma_pm_status = DMA_PMST_STANDBY; + return 0; + } + return -1; +} + +int mxc_dma_pm_resume(void) +{ + unsigned long reg; + if (dma_pm_status == DMA_PMST_RESUME) + return 0; + + /*Enable HCLK_DMA and DMA(ipg clock) */ + dma_pm_status = DMA_PMST_RESUME; + return 0; +} + +int mxc_dma_pm_suspend(void) +{ + unsigned long reg; + if (dma_pm_status == DMA_PMST_SUSPEND) + return 0; + + if (!channel_in_use()) { + /*Disable DMA */ + __disable_dma_clk(); + dma_pm_status = DMA_PMST_SUSPEND; + return 0; + } + return -1; +} + +int mxc_dma_pm_handler(struct pm_dev *dev, pm_request_t rqst, void *data) +{ + int ret = 0; + switch (rqst) { + /*APM doesn't send PM_STANDBY and PM_STANDBY_RESUME request now. */ + case PM_SUSPEND: + ret = dma_pm_suspend(); + break; + case PM_RESUME: + ret = dma_pm_resume(); + break; + } + return ret; +} + +#endif /*DMA_PM */ + +int __init mxc_dma_init(void) +{ + int i; + mxc_dma_channel_t *dma = g_dma_channels; + mx2_dma_priv_t *private = g_dma_privates; + + memset(dma, 0, sizeof(mxc_dma_channel_t) * MXC_DMA_CHANNELS); + for (i = 0; i < MXC_DMA_CHANNELS; i++, dma++, private++) { + dma->channel = i; + dma->private = private; + private->dma_base = + (unsigned int)(IO_ADDRESS(DMA_BASE_ADDR + DMA_CH_BASE(i))); + private->dma_irq = i + MXC_DMA_INTR_0; /*Dma channel interrupt number */ + private->bd_ring = &g_dma_bd_table[i][0]; + } + + mxc_dma_load_info(g_dma_channels); + + dma_clk = clk_get(NULL, "dma_clk"); + clk_enable(dma_clk); + + __raw_writel(0x2, IO_ADDRESS(DMA_BASE_ADDR) + DMA_DCR); /*reset DMA; */ + + disable_dma_clk(); + + /*use module init because create_proc after init_dma */ + g_proc_dir = create_proc_entry("dma", 0, NULL); + g_proc_dir->read_proc = (read_proc_t *) mxc_get_dma_list; + g_proc_dir->data = NULL; + +#ifdef DMA_PM + /* Register the device with power management. */ + dma_pm = pm_register(PM_DMA_DEV, PM_SYS_UNKNOWN, dma_pm_handler); +#endif + + return 0; +} + +arch_initcall(mxc_dma_init); + +EXPORT_SYMBOL(mxc_dma_request_ext); +EXPORT_SYMBOL(mxc_dma_free); +EXPORT_SYMBOL(mxc_dma_callback_set); +EXPORT_SYMBOL(mxc_dma_enable); +EXPORT_SYMBOL(mxc_dma_disable); +EXPORT_SYMBOL(mxc_dma_config); +EXPORT_SYMBOL(mxc_dma_sg_config); +EXPORT_SYMBOL(mxc_dump_dma_register); |