diff options
Diffstat (limited to 'arch/arm/mach-s3c2410/dma.c')
| -rw-r--r-- | arch/arm/mach-s3c2410/dma.c | 1214 |
1 files changed, 0 insertions, 1214 deletions
diff --git a/arch/arm/mach-s3c2410/dma.c b/arch/arm/mach-s3c2410/dma.c deleted file mode 100644 index 65feaf20d23..00000000000 --- a/arch/arm/mach-s3c2410/dma.c +++ /dev/null @@ -1,1214 +0,0 @@ -/* linux/arch/arm/mach-bast/dma.c - * - * (c) 2003-2005 Simtec Electronics - * Ben Dooks <ben@simtec.co.uk> - * - * S3C2410 DMA core - * - * http://www.simtec.co.uk/products/EB2410ITX/ - * - * 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. - * - * Changelog: - * 27-Feb-2005 BJD Added kmem cache for dma descriptors - * 18-Nov-2004 BJD Removed error for loading onto stopped channel - * 10-Nov-2004 BJD Ensure all external symbols exported for modules - * 10-Nov-2004 BJD Use sys_device and sysdev_class for power management - * 08-Aug-2004 BJD Apply rmk's suggestions - * 21-Jul-2004 BJD Ported to linux 2.6 - * 12-Jul-2004 BJD Finished re-write and change of API - * 06-Jul-2004 BJD Rewrote dma code to try and cope with various problems - * 23-May-2003 BJD Created file - * 19-Aug-2003 BJD Cleanup, header fix, added URL - * - * This file is based on the Sangwook Lee/Samsung patches, re-written due - * to various ommisions from the code (such as flexible dma configuration) - * for use with the BAST system board. - * - * The re-write is pretty much complete, and should be good enough for any - * possible DMA function - */ - -#include <linux/config.h> - -#ifdef CONFIG_S3C2410_DMA_DEBUG -#define DEBUG -#endif - -#include <linux/module.h> -#include <linux/init.h> -#include <linux/sched.h> -#include <linux/spinlock.h> -#include <linux/interrupt.h> -#include <linux/sysdev.h> -#include <linux/slab.h> -#include <linux/errno.h> -#include <linux/delay.h> - -#include <asm/system.h> -#include <asm/irq.h> -#include <asm/hardware.h> -#include <asm/io.h> -#include <asm/dma.h> - -#include <asm/mach/dma.h> -#include <asm/arch/map.h> - -/* io map for dma */ -static void __iomem *dma_base; -static kmem_cache_t *dma_kmem; - -/* dma channel state information */ -s3c2410_dma_chan_t s3c2410_chans[S3C2410_DMA_CHANNELS]; - -/* debugging functions */ - -#define BUF_MAGIC (0xcafebabe) - -#define dmawarn(fmt...) printk(KERN_DEBUG fmt) - -#define dma_regaddr(chan, reg) ((chan)->regs + (reg)) - -#if 1 -#define dma_wrreg(chan, reg, val) writel((val), (chan)->regs + (reg)) -#else -static inline void -dma_wrreg(s3c2410_dma_chan_t *chan, int reg, unsigned long val) -{ - pr_debug("writing %08x to register %08x\n",(unsigned int)val,reg); - writel(val, dma_regaddr(chan, reg)); -} - -#endif - -#define dma_rdreg(chan, reg) readl((chan)->regs + (reg)) - -/* captured register state for debug */ - -struct s3c2410_dma_regstate { - unsigned long dcsrc; - unsigned long disrc; - unsigned long dstat; - unsigned long dcon; - unsigned long dmsktrig; -}; - -#ifdef CONFIG_S3C2410_DMA_DEBUG - -/* dmadbg_showregs - * - * simple debug routine to print the current state of the dma registers -*/ - -static void -dmadbg_capture(s3c2410_dma_chan_t *chan, struct s3c2410_dma_regstate *regs) -{ - regs->dcsrc = dma_rdreg(chan, S3C2410_DMA_DCSRC); - regs->disrc = dma_rdreg(chan, S3C2410_DMA_DISRC); - regs->dstat = dma_rdreg(chan, S3C2410_DMA_DSTAT); - regs->dcon = dma_rdreg(chan, S3C2410_DMA_DCON); - regs->dmsktrig = dma_rdreg(chan, S3C2410_DMA_DMASKTRIG); -} - -static void -dmadbg_showregs(const char *fname, int line, s3c2410_dma_chan_t *chan, - struct s3c2410_dma_regstate *regs) -{ - printk(KERN_DEBUG "dma%d: %s:%d: DCSRC=%08lx, DISRC=%08lx, DSTAT=%08lx DMT=%02lx, DCON=%08lx\n", - chan->number, fname, line, - regs->dcsrc, regs->disrc, regs->dstat, regs->dmsktrig, - regs->dcon); -} - -static void -dmadbg_showchan(const char *fname, int line, s3c2410_dma_chan_t *chan) -{ - struct s3c2410_dma_regstate state; - - dmadbg_capture(chan, &state); - - printk(KERN_DEBUG "dma%d: %s:%d: ls=%d, cur=%p, %p %p\n", - chan->number, fname, line, chan->load_state, - chan->curr, chan->next, chan->end); - - dmadbg_showregs(fname, line, chan, &state); -} - -#define dbg_showregs(chan) dmadbg_showregs(__FUNCTION__, __LINE__, (chan)) -#define dbg_showchan(chan) dmadbg_showchan(__FUNCTION__, __LINE__, (chan)) -#else -#define dbg_showregs(chan) do { } while(0) -#define dbg_showchan(chan) do { } while(0) -#endif /* CONFIG_S3C2410_DMA_DEBUG */ - -#define check_channel(chan) \ - do { if ((chan) >= S3C2410_DMA_CHANNELS) { \ - printk(KERN_ERR "%s: invalid channel %d\n", __FUNCTION__, (chan)); \ - return -EINVAL; \ - } } while(0) - - -/* s3c2410_dma_stats_timeout - * - * Update DMA stats from timeout info -*/ - -static void -s3c2410_dma_stats_timeout(s3c2410_dma_stats_t *stats, int val) -{ - if (stats == NULL) - return; - - if (val > stats->timeout_longest) - stats->timeout_longest = val; - if (val < stats->timeout_shortest) - stats->timeout_shortest = val; - - stats->timeout_avg += val; -} - -/* s3c2410_dma_waitforload - * - * wait for the DMA engine to load a buffer, and update the state accordingly -*/ - -static int -s3c2410_dma_waitforload(s3c2410_dma_chan_t *chan, int line) -{ - int timeout = chan->load_timeout; - int took; - - if (chan->load_state != S3C2410_DMALOAD_1LOADED) { - printk(KERN_ERR "dma%d: s3c2410_dma_waitforload() called in loadstate %d from line %d\n", chan->number, chan->load_state, line); - return 0; - } - - if (chan->stats != NULL) - chan->stats->loads++; - - while (--timeout > 0) { - if ((dma_rdreg(chan, S3C2410_DMA_DSTAT) << (32-20)) != 0) { - took = chan->load_timeout - timeout; - - s3c2410_dma_stats_timeout(chan->stats, took); - - switch (chan->load_state) { - case S3C2410_DMALOAD_1LOADED: - chan->load_state = S3C2410_DMALOAD_1RUNNING; - break; - - default: - printk(KERN_ERR "dma%d: unknown load_state in s3c2410_dma_waitforload() %d\n", chan->number, chan->load_state); - } - - return 1; - } - } - - if (chan->stats != NULL) { - chan->stats->timeout_failed++; - } - - return 0; -} - - - -/* s3c2410_dma_loadbuffer - * - * load a buffer, and update the channel state -*/ - -static inline int -s3c2410_dma_loadbuffer(s3c2410_dma_chan_t *chan, - s3c2410_dma_buf_t *buf) -{ - unsigned long reload; - - pr_debug("s3c2410_chan_loadbuffer: loading buff %p (0x%08lx,0x%06x)\n", - buf, (unsigned long)buf->data, buf->size); - - if (buf == NULL) { - dmawarn("buffer is NULL\n"); - return -EINVAL; - } - - /* check the state of the channel before we do anything */ - - if (chan->load_state == S3C2410_DMALOAD_1LOADED) { - dmawarn("load_state is S3C2410_DMALOAD_1LOADED\n"); - } - - if (chan->load_state == S3C2410_DMALOAD_1LOADED_1RUNNING) { - dmawarn("state is S3C2410_DMALOAD_1LOADED_1RUNNING\n"); - } - - /* it would seem sensible if we are the last buffer to not bother - * with the auto-reload bit, so that the DMA engine will not try - * and load another transfer after this one has finished... - */ - if (chan->load_state == S3C2410_DMALOAD_NONE) { - pr_debug("load_state is none, checking for noreload (next=%p)\n", - buf->next); - reload = (buf->next == NULL) ? S3C2410_DCON_NORELOAD : 0; - } else { - pr_debug("load_state is %d => autoreload\n", chan->load_state); - reload = S3C2410_DCON_AUTORELOAD; - } - - writel(buf->data, chan->addr_reg); - - dma_wrreg(chan, S3C2410_DMA_DCON, - chan->dcon | reload | (buf->size/chan->xfer_unit)); - - chan->next = buf->next; - - /* update the state of the channel */ - - switch (chan->load_state) { - case S3C2410_DMALOAD_NONE: - chan->load_state = S3C2410_DMALOAD_1LOADED; - break; - - case S3C2410_DMALOAD_1RUNNING: - chan->load_state = S3C2410_DMALOAD_1LOADED_1RUNNING; - break; - - default: - dmawarn("dmaload: unknown state %d in loadbuffer\n", - chan->load_state); - break; - } - - return 0; -} - -/* s3c2410_dma_call_op - * - * small routine to call the op routine with the given op if it has been - * registered -*/ - -static void -s3c2410_dma_call_op(s3c2410_dma_chan_t *chan, s3c2410_chan_op_t op) -{ - if (chan->op_fn != NULL) { - (chan->op_fn)(chan, op); - } -} - -/* s3c2410_dma_buffdone - * - * small wrapper to check if callback routine needs to be called, and - * if so, call it -*/ - -static inline void -s3c2410_dma_buffdone(s3c2410_dma_chan_t *chan, s3c2410_dma_buf_t *buf, - s3c2410_dma_buffresult_t result) -{ - pr_debug("callback_fn=%p, buf=%p, id=%p, size=%d, result=%d\n", - chan->callback_fn, buf, buf->id, buf->size, result); - - if (chan->callback_fn != NULL) { - (chan->callback_fn)(chan, buf->id, buf->size, result); - } -} - -/* s3c2410_dma_start - * - * start a dma channel going -*/ - -static int s3c2410_dma_start(s3c2410_dma_chan_t *chan) -{ - unsigned long tmp; - unsigned long flags; - - pr_debug("s3c2410_start_dma: channel=%d\n", chan->number); - - local_irq_save(flags); - - if (chan->state == S3C2410_DMA_RUNNING) { - pr_debug("s3c2410_start_dma: already running (%d)\n", chan->state); - local_irq_restore(flags); - return 0; - } - - chan->state = S3C2410_DMA_RUNNING; - - /* check wether there is anything to load, and if not, see - * if we can find anything to load - */ - - if (chan->load_state == S3C2410_DMALOAD_NONE) { - if (chan->next == NULL) { - printk(KERN_ERR "dma%d: channel has nothing loaded\n", - chan->number); - chan->state = S3C2410_DMA_IDLE; - local_irq_restore(flags); - return -EINVAL; - } - - s3c2410_dma_loadbuffer(chan, chan->next); - } - - dbg_showchan(chan); - - /* enable the channel */ - - if (!chan->irq_enabled) { - enable_irq(chan->irq); - chan->irq_enabled = 1; - } - - /* start the channel going */ - - tmp = dma_rdreg(chan, S3C2410_DMA_DMASKTRIG); - tmp &= ~S3C2410_DMASKTRIG_STOP; - tmp |= S3C2410_DMASKTRIG_ON; - dma_wrreg(chan, S3C2410_DMA_DMASKTRIG, tmp); - - pr_debug("wrote %08lx to DMASKTRIG\n", tmp); - -#if 0 - /* the dma buffer loads should take care of clearing the AUTO - * reloading feature */ - tmp = dma_rdreg(chan, S3C2410_DMA_DCON); - tmp &= ~S3C2410_DCON_NORELOAD; - dma_wrreg(chan, S3C2410_DMA_DCON, tmp); -#endif - - s3c2410_dma_call_op(chan, S3C2410_DMAOP_START); - - dbg_showchan(chan); - - local_irq_restore(flags); - return 0; -} - -/* s3c2410_dma_canload - * - * work out if we can queue another buffer into the DMA engine -*/ - -static int -s3c2410_dma_canload(s3c2410_dma_chan_t *chan) -{ - if (chan->load_state == S3C2410_DMALOAD_NONE || - chan->load_state == S3C2410_DMALOAD_1RUNNING) - return 1; - - return 0; -} - - -/* s3c2410_dma_enqueue - * - * queue an given buffer for dma transfer. - * - * id the device driver's id information for this buffer - * data the physical address of the buffer data - * size the size of the buffer in bytes - * - * If the channel is not running, then the flag S3C2410_DMAF_AUTOSTART - * is checked, and if set, the channel is started. If this flag isn't set, - * then an error will be returned. - * - * It is possible to queue more than one DMA buffer onto a channel at - * once, and the code will deal with the re-loading of the next buffer - * when necessary. -*/ - -int s3c2410_dma_enqueue(unsigned int channel, void *id, - dma_addr_t data, int size) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - s3c2410_dma_buf_t *buf; - unsigned long flags; - - check_channel(channel); - - pr_debug("%s: id=%p, data=%08x, size=%d\n", - __FUNCTION__, id, (unsigned int)data, size); - - buf = kmem_cache_alloc(dma_kmem, GFP_ATOMIC); - if (buf == NULL) { - pr_debug("%s: out of memory (%ld alloc)\n", - __FUNCTION__, sizeof(*buf)); - return -ENOMEM; - } - - pr_debug("%s: new buffer %p\n", __FUNCTION__, buf); - - //dbg_showchan(chan); - - buf->next = NULL; - buf->data = buf->ptr = data; - buf->size = size; - buf->id = id; - buf->magic = BUF_MAGIC; - - local_irq_save(flags); - - if (chan->curr == NULL) { - /* we've got nothing loaded... */ - pr_debug("%s: buffer %p queued onto empty channel\n", - __FUNCTION__, buf); - - chan->curr = buf; - chan->end = buf; - chan->next = NULL; - } else { - pr_debug("dma%d: %s: buffer %p queued onto non-empty channel\n", - chan->number, __FUNCTION__, buf); - - if (chan->end == NULL) - pr_debug("dma%d: %s: %p not empty, and chan->end==NULL?\n", - chan->number, __FUNCTION__, chan); - - chan->end->next = buf; - chan->end = buf; - } - - /* if necessary, update the next buffer field */ - if (chan->next == NULL) - chan->next = buf; - - /* check to see if we can load a buffer */ - if (chan->state == S3C2410_DMA_RUNNING) { - if (chan->load_state == S3C2410_DMALOAD_1LOADED && 1) { - if (s3c2410_dma_waitforload(chan, __LINE__) == 0) { - printk(KERN_ERR "dma%d: loadbuffer:" - "timeout loading buffer\n", - chan->number); - dbg_showchan(chan); - local_irq_restore(flags); - return -EINVAL; - } - } - - while (s3c2410_dma_canload(chan) && chan->next != NULL) { - s3c2410_dma_loadbuffer(chan, chan->next); - } - } else if (chan->state == S3C2410_DMA_IDLE) { - if (chan->flags & S3C2410_DMAF_AUTOSTART) { - s3c2410_dma_ctrl(chan->number, S3C2410_DMAOP_START); - } - } - - local_irq_restore(flags); - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_enqueue); - -static inline void -s3c2410_dma_freebuf(s3c2410_dma_buf_t *buf) -{ - int magicok = (buf->magic == BUF_MAGIC); - - buf->magic = -1; - - if (magicok) { - kmem_cache_free(dma_kmem, buf); - } else { - printk("s3c2410_dma_freebuf: buff %p with bad magic\n", buf); - } -} - -/* s3c2410_dma_lastxfer - * - * called when the system is out of buffers, to ensure that the channel - * is prepared for shutdown. -*/ - -static inline void -s3c2410_dma_lastxfer(s3c2410_dma_chan_t *chan) -{ - pr_debug("dma%d: s3c2410_dma_lastxfer: load_state %d\n", - chan->number, chan->load_state); - - switch (chan->load_state) { - case S3C2410_DMALOAD_NONE: - break; - - case S3C2410_DMALOAD_1LOADED: - if (s3c2410_dma_waitforload(chan, __LINE__) == 0) { - /* flag error? */ - printk(KERN_ERR "dma%d: timeout waiting for load\n", - chan->number); - return; - } - break; - - default: - pr_debug("dma%d: lastxfer: unhandled load_state %d with no next", - chan->number, chan->load_state); - return; - - } - - /* hopefully this'll shut the damned thing up after the transfer... */ - dma_wrreg(chan, S3C2410_DMA_DCON, chan->dcon | S3C2410_DCON_NORELOAD); -} - - -#define dmadbg2(x...) - -static irqreturn_t -s3c2410_dma_irq(int irq, void *devpw, struct pt_regs *regs) -{ - s3c2410_dma_chan_t *chan = (s3c2410_dma_chan_t *)devpw; - s3c2410_dma_buf_t *buf; - - buf = chan->curr; - - dbg_showchan(chan); - - /* modify the channel state */ - - switch (chan->load_state) { - case S3C2410_DMALOAD_1RUNNING: - /* TODO - if we are running only one buffer, we probably - * want to reload here, and then worry about the buffer - * callback */ - - chan->load_state = S3C2410_DMALOAD_NONE; - break; - - case S3C2410_DMALOAD_1LOADED: - /* iirc, we should go back to NONE loaded here, we - * had a buffer, and it was never verified as being - * loaded. - */ - - chan->load_state = S3C2410_DMALOAD_NONE; - break; - - case S3C2410_DMALOAD_1LOADED_1RUNNING: - /* we'll worry about checking to see if another buffer is - * ready after we've called back the owner. This should - * ensure we do not wait around too long for the DMA - * engine to start the next transfer - */ - - chan->load_state = S3C2410_DMALOAD_1LOADED; - break; - - case S3C2410_DMALOAD_NONE: - printk(KERN_ERR "dma%d: IRQ with no loaded buffer?\n", - chan->number); - break; - - default: - printk(KERN_ERR "dma%d: IRQ in invalid load_state %d\n", - chan->number, chan->load_state); - break; - } - - if (buf != NULL) { - /* update the chain to make sure that if we load any more - * buffers when we call the callback function, things should - * work properly */ - - chan->curr = buf->next; - buf->next = NULL; - - if (buf->magic != BUF_MAGIC) { - printk(KERN_ERR "dma%d: %s: buf %p incorrect magic\n", - chan->number, __FUNCTION__, buf); - return IRQ_HANDLED; - } - - s3c2410_dma_buffdone(chan, buf, S3C2410_RES_OK); - - /* free resouces */ - s3c2410_dma_freebuf(buf); - } else { - } - - if (chan->next != NULL) { - unsigned long flags; - - switch (chan->load_state) { - case S3C2410_DMALOAD_1RUNNING: - /* don't need to do anything for this state */ - break; - - case S3C2410_DMALOAD_NONE: - /* can load buffer immediately */ - break; - - case S3C2410_DMALOAD_1LOADED: - if (s3c2410_dma_waitforload(chan, __LINE__) == 0) { - /* flag error? */ - printk(KERN_ERR "dma%d: timeout waiting for load\n", - chan->number); - return IRQ_HANDLED; - } - - break; - - case S3C2410_DMALOAD_1LOADED_1RUNNING: - goto no_load; - - default: - printk(KERN_ERR "dma%d: unknown load_state in irq, %d\n", - chan->number, chan->load_state); - return IRQ_HANDLED; - } - - local_irq_save(flags); - s3c2410_dma_loadbuffer(chan, chan->next); - local_irq_restore(flags); - } else { - s3c2410_dma_lastxfer(chan); - - /* see if we can stop this channel.. */ - if (chan->load_state == S3C2410_DMALOAD_NONE) { - pr_debug("dma%d: end of transfer, stopping channel (%ld)\n", - chan->number, jiffies); - s3c2410_dma_ctrl(chan->number, S3C2410_DMAOP_STOP); - } - } - - no_load: - return IRQ_HANDLED; -} - - - -/* s3c2410_request_dma - * - * get control of an dma channel -*/ - -int s3c2410_dma_request(unsigned int channel, s3c2410_dma_client_t *client, - void *dev) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - unsigned long flags; - int err; - - pr_debug("dma%d: s3c2410_request_dma: client=%s, dev=%p\n", - channel, client->name, dev); - - check_channel(channel); - - local_irq_save(flags); - - dbg_showchan(chan); - - if (chan->in_use) { - if (client != chan->client) { - printk(KERN_ERR "dma%d: already in use\n", channel); - local_irq_restore(flags); - return -EBUSY; - } else { - printk(KERN_ERR "dma%d: client already has channel\n", channel); - } - } - - chan->client = client; - chan->in_use = 1; - - if (!chan->irq_claimed) { - pr_debug("dma%d: %s : requesting irq %d\n", - channel, __FUNCTION__, chan->irq); - - err = request_irq(chan->irq, s3c2410_dma_irq, SA_INTERRUPT, - client->name, (void *)chan); - - if (err) { - chan->in_use = 0; - local_irq_restore(flags); - - printk(KERN_ERR "%s: cannot get IRQ %d for DMA %d\n", - client->name, chan->irq, chan->number); - return err; - } - - chan->irq_claimed = 1; - chan->irq_enabled = 1; - } - - local_irq_restore(flags); - - /* need to setup */ - - pr_debug("%s: channel initialised, %p\n", __FUNCTION__, chan); - - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_request); - -/* s3c2410_dma_free - * - * release the given channel back to the system, will stop and flush - * any outstanding transfers, and ensure the channel is ready for the - * next claimant. - * - * Note, although a warning is currently printed if the freeing client - * info is not the same as the registrant's client info, the free is still - * allowed to go through. -*/ - -int s3c2410_dma_free(dmach_t channel, s3c2410_dma_client_t *client) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - unsigned long flags; - - check_channel(channel); - - local_irq_save(flags); - - - if (chan->client != client) { - printk(KERN_WARNING "dma%d: possible free from different client (channel %p, passed %p)\n", - channel, chan->client, client); - } - - /* sort out stopping and freeing the channel */ - - if (chan->state != S3C2410_DMA_IDLE) { - pr_debug("%s: need to stop dma channel %p\n", - __FUNCTION__, chan); - - /* possibly flush the channel */ - s3c2410_dma_ctrl(channel, S3C2410_DMAOP_STOP); - } - - chan->client = NULL; - chan->in_use = 0; - - if (chan->irq_claimed) - free_irq(chan->irq, (void *)chan); - chan->irq_claimed = 0; - - local_irq_restore(flags); - - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_free); - -static int s3c2410_dma_dostop(s3c2410_dma_chan_t *chan) -{ - unsigned long tmp; - unsigned long flags; - - pr_debug("%s:\n", __FUNCTION__); - - dbg_showchan(chan); - - local_irq_save(flags); - - s3c2410_dma_call_op(chan, S3C2410_DMAOP_STOP); - - tmp = dma_rdreg(chan, S3C2410_DMA_DMASKTRIG); - tmp |= S3C2410_DMASKTRIG_STOP; - dma_wrreg(chan, S3C2410_DMA_DMASKTRIG, tmp); - -#if 0 - /* should also clear interrupts, according to WinCE BSP */ - tmp = dma_rdreg(chan, S3C2410_DMA_DCON); - tmp |= S3C2410_DCON_NORELOAD; - dma_wrreg(chan, S3C2410_DMA_DCON, tmp); -#endif - - chan->state = S3C2410_DMA_IDLE; - chan->load_state = S3C2410_DMALOAD_NONE; - - local_irq_restore(flags); - - return 0; -} - -/* s3c2410_dma_flush - * - * stop the channel, and remove all current and pending transfers -*/ - -static int s3c2410_dma_flush(s3c2410_dma_chan_t *chan) -{ - s3c2410_dma_buf_t *buf, *next; - unsigned long flags; - - pr_debug("%s:\n", __FUNCTION__); - - local_irq_save(flags); - - if (chan->state != S3C2410_DMA_IDLE) { - pr_debug("%s: stopping channel...\n", __FUNCTION__ ); - s3c2410_dma_ctrl(chan->number, S3C2410_DMAOP_STOP); - } - - buf = chan->curr; - if (buf == NULL) - buf = chan->next; - - chan->curr = chan->next = chan->end = NULL; - - if (buf != NULL) { - for ( ; buf != NULL; buf = next) { - next = buf->next; - - pr_debug("%s: free buffer %p, next %p\n", - __FUNCTION__, buf, buf->next); - - s3c2410_dma_buffdone(chan, buf, S3C2410_RES_ABORT); - s3c2410_dma_freebuf(buf); - } - } - - local_irq_restore(flags); - - return 0; -} - - -int -s3c2410_dma_ctrl(dmach_t channel, s3c2410_chan_op_t op) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - - check_channel(channel); - - switch (op) { - case S3C2410_DMAOP_START: - return s3c2410_dma_start(chan); - - case S3C2410_DMAOP_STOP: - return s3c2410_dma_dostop(chan); - - case S3C2410_DMAOP_PAUSE: - return -ENOENT; - - case S3C2410_DMAOP_RESUME: - return -ENOENT; - - case S3C2410_DMAOP_FLUSH: - return s3c2410_dma_flush(chan); - - case S3C2410_DMAOP_TIMEOUT: - return 0; - - } - - return -ENOENT; /* unknown, don't bother */ -} - -EXPORT_SYMBOL(s3c2410_dma_ctrl); - -/* DMA configuration for each channel - * - * DISRCC -> source of the DMA (AHB,APB) - * DISRC -> source address of the DMA - * DIDSTC -> destination of the DMA (AHB,APD) - * DIDST -> destination address of the DMA -*/ - -/* s3c2410_dma_config - * - * xfersize: size of unit in bytes (1,2,4) - * dcon: base value of the DCONx register -*/ - -int s3c2410_dma_config(dmach_t channel, - int xferunit, - int dcon) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - - pr_debug("%s: chan=%d, xfer_unit=%d, dcon=%08x\n", - __FUNCTION__, channel, xferunit, dcon); - - check_channel(channel); - - switch (xferunit) { - case 1: - dcon |= S3C2410_DCON_BYTE; - break; - - case 2: - dcon |= S3C2410_DCON_HALFWORD; - break; - - case 4: - dcon |= S3C2410_DCON_WORD; - break; - - default: - pr_debug("%s: bad transfer size %d\n", __FUNCTION__, xferunit); - return -EINVAL; - } - - dcon |= S3C2410_DCON_HWTRIG; - dcon |= S3C2410_DCON_INTREQ; - - pr_debug("%s: dcon now %08x\n", __FUNCTION__, dcon); - - chan->dcon = dcon; - chan->xfer_unit = xferunit; - - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_config); - -int s3c2410_dma_setflags(dmach_t channel, unsigned int flags) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - - check_channel(channel); - - pr_debug("%s: chan=%p, flags=%08x\n", __FUNCTION__, chan, flags); - - chan->flags = flags; - - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_setflags); - - -/* do we need to protect the settings of the fields from - * irq? -*/ - -int s3c2410_dma_set_opfn(dmach_t channel, s3c2410_dma_opfn_t rtn) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - - check_channel(channel); - - pr_debug("%s: chan=%p, op rtn=%p\n", __FUNCTION__, chan, rtn); - - chan->op_fn = rtn; - - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_set_opfn); - -int s3c2410_dma_set_buffdone_fn(dmach_t channel, s3c2410_dma_cbfn_t rtn) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - - check_channel(channel); - - pr_debug("%s: chan=%p, callback rtn=%p\n", __FUNCTION__, chan, rtn); - - chan->callback_fn = rtn; - - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_set_buffdone_fn); - -/* s3c2410_dma_devconfig - * - * configure the dma source/destination hardware type and address - * - * source: S3C2410_DMASRC_HW: source is hardware - * S3C2410_DMASRC_MEM: source is memory - * - * hwcfg: the value for xxxSTCn register, - * bit 0: 0=increment pointer, 1=leave pointer - * bit 1: 0=soucre is AHB, 1=soucre is APB - * - * devaddr: physical address of the source -*/ - -int s3c2410_dma_devconfig(int channel, - s3c2410_dmasrc_t source, - int hwcfg, - unsigned long devaddr) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - - check_channel(channel); - - pr_debug("%s: source=%d, hwcfg=%08x, devaddr=%08lx\n", - __FUNCTION__, (int)source, hwcfg, devaddr); - - chan->source = source; - chan->dev_addr = devaddr; - - switch (source) { - case S3C2410_DMASRC_HW: - /* source is hardware */ - pr_debug("%s: hw source, devaddr=%08lx, hwcfg=%d\n", - __FUNCTION__, devaddr, hwcfg); - dma_wrreg(chan, S3C2410_DMA_DISRCC, hwcfg & 3); - dma_wrreg(chan, S3C2410_DMA_DISRC, devaddr); - dma_wrreg(chan, S3C2410_DMA_DIDSTC, (0<<1) | (0<<0)); - - chan->addr_reg = dma_regaddr(chan, S3C2410_DMA_DIDST); - return 0; - - case S3C2410_DMASRC_MEM: - /* source is memory */ - pr_debug( "%s: mem source, devaddr=%08lx, hwcfg=%d\n", - __FUNCTION__, devaddr, hwcfg); - dma_wrreg(chan, S3C2410_DMA_DISRCC, (0<<1) | (0<<0)); - dma_wrreg(chan, S3C2410_DMA_DIDST, devaddr); - dma_wrreg(chan, S3C2410_DMA_DIDSTC, hwcfg & 3); - - chan->addr_reg = dma_regaddr(chan, S3C2410_DMA_DISRC); - return 0; - } - - printk(KERN_ERR "dma%d: invalid source type (%d)\n", channel, source); - return -EINVAL; -} - -EXPORT_SYMBOL(s3c2410_dma_devconfig); - -/* s3c2410_dma_getposition - * - * returns the current transfer points for the dma source and destination -*/ - -int s3c2410_dma_getposition(dmach_t channel, dma_addr_t *src, dma_addr_t *dst) -{ - s3c2410_dma_chan_t *chan = &s3c2410_chans[channel]; - - check_channel(channel); - - if (src != NULL) - *src = dma_rdreg(chan, S3C2410_DMA_DCSRC); - - if (dst != NULL) - *dst = dma_rdreg(chan, S3C2410_DMA_DCDST); - - return 0; -} - -EXPORT_SYMBOL(s3c2410_dma_getposition); - - -/* system device class */ - -#ifdef CONFIG_PM - -static int s3c2410_dma_suspend(struct sys_device *dev, pm_message_t state) -{ - s3c2410_dma_chan_t *cp = container_of(dev, s3c2410_dma_chan_t, dev); - - printk(KERN_DEBUG "suspending dma channel %d\n", cp->number); - - if (dma_rdreg(cp, S3C2410_DMA_DMASKTRIG) & S3C2410_DMASKTRIG_ON) { - /* the dma channel is still working, which is probably - * a bad thing to do over suspend/resume. We stop the - * channel and assume that the client is either going to - * retry after resume, or that it is broken. - */ - - printk(KERN_INFO "dma: stopping channel %d due to suspend\n", - cp->number); - - s3c2410_dma_dostop(cp); - } - - return 0; -} - -static int s3c2410_dma_resume(struct sys_device *dev) -{ - return 0; -} - -#else -#define s3c2410_dma_suspend NULL -#define s3c2410_dma_resume NULL -#endif /* CONFIG_PM */ - -static struct sysdev_class dma_sysclass = { - set_kset_name("s3c24xx-dma"), - .suspend = s3c2410_dma_suspend, - .resume = s3c2410_dma_resume, -}; - -/* kmem cache implementation */ - -static void s3c2410_dma_cache_ctor(void *p, kmem_cache_t *c, unsigned long f) -{ - memset(p, 0, sizeof(s3c2410_dma_buf_t)); -} - - -/* initialisation code */ - -static int __init s3c2410_init_dma(void) -{ - s3c2410_dma_chan_t *cp; - int channel; - int ret; - - printk("S3C2410 DMA Driver, (c) 2003-2004 Simtec Electronics\n"); - - dma_base = ioremap(S3C2410_PA_DMA, 0x200); - if (dma_base == NULL) { - printk(KERN_ERR "dma failed to remap register block\n"); - return -ENOMEM; - } - - ret = sysdev_class_register(&dma_sysclass); - if (ret != 0) { - printk(KERN_ERR "dma sysclass registration failed\n"); - goto err; - } - - dma_kmem = kmem_cache_create("dma_desc", sizeof(s3c2410_dma_buf_t), 0, - SLAB_HWCACHE_ALIGN, - s3c2410_dma_cache_ctor, NULL); - - if (dma_kmem == NULL) { - printk(KERN_ERR "dma failed to make kmem cache\n"); - ret = -ENOMEM; - goto err; - } - - for (channel = 0; channel < S3C2410_DMA_CHANNELS; channel++) { - cp = &s3c2410_chans[channel]; - - memset(cp, 0, sizeof(s3c2410_dma_chan_t)); - - /* dma channel irqs are in order.. */ - cp->number = channel; - cp->irq = channel + IRQ_DMA0; - cp->regs = dma_base + (channel*0x40); - - /* point current stats somewhere */ - cp->stats = &cp->stats_store; - cp->stats_store.timeout_shortest = LONG_MAX; - - /* basic channel configuration */ - - cp->load_timeout = 1<<18; - - /* register system device */ - - cp->dev.cls = &dma_sysclass; - cp->dev.id = channel; - ret = sysdev_register(&cp->dev); - - printk("DMA channel %d at %p, irq %d\n", - cp->number, cp->regs, cp->irq); - } - - return 0; - - err: - kmem_cache_destroy(dma_kmem); - iounmap(dma_base); - dma_base = NULL; - return ret; -} - -__initcall(s3c2410_init_dma); |