dma40: Improve the logic of stopping logical chan
authorNarayanan G <narayanan.gopalakrishnan@stericsson.com>
Thu, 9 Feb 2012 07:11:37 +0000 (12:41 +0530)
committerVinod Koul <vinod.koul@linux.intel.com>
Mon, 23 Apr 2012 12:26:17 +0000 (17:56 +0530)
can be directly stopped by issuing a SUSPEND_REQ on the EE
bits. There is no need to suspend the physical channel and
restart it.

Also, the support for pre-V2 hw is discontinued.

EE bits for writing:

00: disable only if AS=11 or AS=00
01: enable
10: suspend_req only if AS=01 & EE=01 or EE=11
11: round / no change for writing

Signed-off-by: Narayanan G <narayanan.gopalakrishnan@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
drivers/dma/ste_dma40.c
drivers/dma/ste_dma40_ll.h

index bdd41d4..c5f26cc 100644 (file)
@@ -69,6 +69,22 @@ enum d40_command {
 };
 
 /*
+ * enum d40_events - The different Event Enables for the event lines.
+ *
+ * @D40_DEACTIVATE_EVENTLINE: De-activate Event line, stopping the logical chan.
+ * @D40_ACTIVATE_EVENTLINE: Activate the Event line, to start a logical chan.
+ * @D40_SUSPEND_REQ_EVENTLINE: Requesting for suspending a event line.
+ * @D40_ROUND_EVENTLINE: Status check for event line.
+ */
+
+enum d40_events {
+       D40_DEACTIVATE_EVENTLINE        = 0,
+       D40_ACTIVATE_EVENTLINE          = 1,
+       D40_SUSPEND_REQ_EVENTLINE       = 2,
+       D40_ROUND_EVENTLINE             = 3
+};
+
+/*
  * These are the registers that has to be saved and later restored
  * when the DMA hw is powered off.
  * TODO: Add save/restore of D40_DREG_GCC on dma40 v3 or later, if that works.
@@ -870,8 +886,8 @@ static void d40_save_restore_registers(struct d40_base *base, bool save)
 }
 #endif
 
-static int d40_channel_execute_command(struct d40_chan *d40c,
-                                      enum d40_command command)
+static int __d40_execute_command_phy(struct d40_chan *d40c,
+                                    enum d40_command command)
 {
        u32 status;
        int i;
@@ -880,6 +896,12 @@ static int d40_channel_execute_command(struct d40_chan *d40c,
        unsigned long flags;
        u32 wmask;
 
+       if (command == D40_DMA_STOP) {
+               ret = __d40_execute_command_phy(d40c, D40_DMA_SUSPEND_REQ);
+               if (ret)
+                       return ret;
+       }
+
        spin_lock_irqsave(&d40c->base->execmd_lock, flags);
 
        if (d40c->phy_chan->num % 2 == 0)
@@ -973,67 +995,109 @@ static void d40_term_all(struct d40_chan *d40c)
                }
 
        d40c->pending_tx = 0;
-       d40c->busy = false;
 }
 
-static void __d40_config_set_event(struct d40_chan *d40c, bool enable,
-                                  u32 event, int reg)
+static void __d40_config_set_event(struct d40_chan *d40c,
+                                  enum d40_events event_type, u32 event,
+                                  int reg)
 {
        void __iomem *addr = chan_base(d40c) + reg;
        int tries;
+       u32 status;
+
+       switch (event_type) {
+
+       case D40_DEACTIVATE_EVENTLINE:
 
-       if (!enable) {
                writel((D40_DEACTIVATE_EVENTLINE << D40_EVENTLINE_POS(event))
                       | ~D40_EVENTLINE_MASK(event), addr);
-               return;
-       }
+               break;
+
+       case D40_SUSPEND_REQ_EVENTLINE:
+               status = (readl(addr) & D40_EVENTLINE_MASK(event)) >>
+                         D40_EVENTLINE_POS(event);
+
+               if (status == D40_DEACTIVATE_EVENTLINE ||
+                   status == D40_SUSPEND_REQ_EVENTLINE)
+                       break;
 
+               writel((D40_SUSPEND_REQ_EVENTLINE << D40_EVENTLINE_POS(event))
+                      | ~D40_EVENTLINE_MASK(event), addr);
+
+               for (tries = 0 ; tries < D40_SUSPEND_MAX_IT; tries++) {
+
+                       status = (readl(addr) & D40_EVENTLINE_MASK(event)) >>
+                                 D40_EVENTLINE_POS(event);
+
+                       cpu_relax();
+                       /*
+                        * Reduce the number of bus accesses while
+                        * waiting for the DMA to suspend.
+                        */
+                       udelay(3);
+
+                       if (status == D40_DEACTIVATE_EVENTLINE)
+                               break;
+               }
+
+               if (tries == D40_SUSPEND_MAX_IT) {
+                       chan_err(d40c,
+                               "unable to stop the event_line chl %d (log: %d)"
+                               "status %x\n", d40c->phy_chan->num,
+                                d40c->log_num, status);
+               }
+               break;
+
+       case D40_ACTIVATE_EVENTLINE:
        /*
         * The hardware sometimes doesn't register the enable when src and dst
         * event lines are active on the same logical channel.  Retry to ensure
         * it does.  Usually only one retry is sufficient.
         */
-       tries = 100;
-       while (--tries) {
-               writel((D40_ACTIVATE_EVENTLINE << D40_EVENTLINE_POS(event))
-                      | ~D40_EVENTLINE_MASK(event), addr);
+               tries = 100;
+               while (--tries) {
+                       writel((D40_ACTIVATE_EVENTLINE <<
+                               D40_EVENTLINE_POS(event)) |
+                               ~D40_EVENTLINE_MASK(event), addr);
 
-               if (readl(addr) & D40_EVENTLINE_MASK(event))
-                       break;
-       }
+                       if (readl(addr) & D40_EVENTLINE_MASK(event))
+                               break;
+               }
 
-       if (tries != 99)
-               dev_dbg(chan2dev(d40c),
-                       "[%s] workaround enable S%cLNK (%d tries)\n",
-                       __func__, reg == D40_CHAN_REG_SSLNK ? 'S' : 'D',
-                       100 - tries);
+               if (tries != 99)
+                       dev_dbg(chan2dev(d40c),
+                               "[%s] workaround enable S%cLNK (%d tries)\n",
+                               __func__, reg == D40_CHAN_REG_SSLNK ? 'S' : 'D',
+                               100 - tries);
 
-       WARN_ON(!tries);
-}
+               WARN_ON(!tries);
+               break;
 
-static void d40_config_set_event(struct d40_chan *d40c, bool do_enable)
-{
-       unsigned long flags;
+       case D40_ROUND_EVENTLINE:
+               BUG();
+               break;
 
-       spin_lock_irqsave(&d40c->phy_chan->lock, flags);
+       }
+}
 
+static void d40_config_set_event(struct d40_chan *d40c,
+                                enum d40_events event_type)
+{
        /* Enable event line connected to device (or memcpy) */
        if ((d40c->dma_cfg.dir ==  STEDMA40_PERIPH_TO_MEM) ||
            (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_PERIPH)) {
                u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.src_dev_type);
 
-               __d40_config_set_event(d40c, do_enable, event,
+               __d40_config_set_event(d40c, event_type, event,
                                       D40_CHAN_REG_SSLNK);
        }
 
        if (d40c->dma_cfg.dir !=  STEDMA40_PERIPH_TO_MEM) {
                u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dst_dev_type);
 
-               __d40_config_set_event(d40c, do_enable, event,
+               __d40_config_set_event(d40c, event_type, event,
                                       D40_CHAN_REG_SDLNK);
        }
-
-       spin_unlock_irqrestore(&d40c->phy_chan->lock, flags);
 }
 
 static u32 d40_chan_has_events(struct d40_chan *d40c)
@@ -1047,6 +1111,64 @@ static u32 d40_chan_has_events(struct d40_chan *d40c)
        return val;
 }
 
+static int
+__d40_execute_command_log(struct d40_chan *d40c, enum d40_command command)
+{
+       unsigned long flags;
+       int ret = 0;
+       u32 active_status;
+       void __iomem *active_reg;
+
+       if (d40c->phy_chan->num % 2 == 0)
+               active_reg = d40c->base->virtbase + D40_DREG_ACTIVE;
+       else
+               active_reg = d40c->base->virtbase + D40_DREG_ACTIVO;
+
+
+       spin_lock_irqsave(&d40c->phy_chan->lock, flags);
+
+       switch (command) {
+       case D40_DMA_STOP:
+       case D40_DMA_SUSPEND_REQ:
+
+               active_status = (readl(active_reg) &
+                                D40_CHAN_POS_MASK(d40c->phy_chan->num)) >>
+                                D40_CHAN_POS(d40c->phy_chan->num);
+
+               if (active_status == D40_DMA_RUN)
+                       d40_config_set_event(d40c, D40_SUSPEND_REQ_EVENTLINE);
+               else
+                       d40_config_set_event(d40c, D40_DEACTIVATE_EVENTLINE);
+
+               if (!d40_chan_has_events(d40c) && (command == D40_DMA_STOP))
+                       ret = __d40_execute_command_phy(d40c, command);
+
+               break;
+
+       case D40_DMA_RUN:
+
+               d40_config_set_event(d40c, D40_ACTIVATE_EVENTLINE);
+               ret = __d40_execute_command_phy(d40c, command);
+               break;
+
+       case D40_DMA_SUSPENDED:
+               BUG();
+               break;
+       }
+
+       spin_unlock_irqrestore(&d40c->phy_chan->lock, flags);
+       return ret;
+}
+
+static int d40_channel_execute_command(struct d40_chan *d40c,
+                                      enum d40_command command)
+{
+       if (chan_is_logical(d40c))
+               return __d40_execute_command_log(d40c, command);
+       else
+               return __d40_execute_command_phy(d40c, command);
+}
+
 static u32 d40_get_prmo(struct d40_chan *d40c)
 {
        static const unsigned int phy_map[] = {
@@ -1149,15 +1271,7 @@ static int d40_pause(struct d40_chan *d40c)
        spin_lock_irqsave(&d40c->lock, flags);
 
        res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
-       if (res == 0) {
-               if (chan_is_logical(d40c)) {
-                       d40_config_set_event(d40c, false);
-                       /* Resume the other logical channels if any */
-                       if (d40_chan_has_events(d40c))
-                               res = d40_channel_execute_command(d40c,
-                                                                 D40_DMA_RUN);
-               }
-       }
+
        pm_runtime_mark_last_busy(d40c->base->dev);
        pm_runtime_put_autosuspend(d40c->base->dev);
        spin_unlock_irqrestore(&d40c->lock, flags);
@@ -1174,45 +1288,17 @@ static int d40_resume(struct d40_chan *d40c)
 
        spin_lock_irqsave(&d40c->lock, flags);
        pm_runtime_get_sync(d40c->base->dev);
-       if (d40c->base->rev == 0)
-               if (chan_is_logical(d40c)) {
-                       res = d40_channel_execute_command(d40c,
-                                                         D40_DMA_SUSPEND_REQ);
-                       goto no_suspend;
-               }
 
        /* If bytes left to transfer or linked tx resume job */
-       if (d40_residue(d40c) || d40_tx_is_linked(d40c)) {
-
-               if (chan_is_logical(d40c))
-                       d40_config_set_event(d40c, true);
-
+       if (d40_residue(d40c) || d40_tx_is_linked(d40c))
                res = d40_channel_execute_command(d40c, D40_DMA_RUN);
-       }
 
-no_suspend:
        pm_runtime_mark_last_busy(d40c->base->dev);
        pm_runtime_put_autosuspend(d40c->base->dev);
        spin_unlock_irqrestore(&d40c->lock, flags);
        return res;
 }
 
-static int d40_terminate_all(struct d40_chan *chan)
-{
-       unsigned long flags;
-       int ret = 0;
-
-       ret = d40_pause(chan);
-       if (!ret && chan_is_physical(chan))
-               ret = d40_channel_execute_command(chan, D40_DMA_STOP);
-
-       spin_lock_irqsave(&chan->lock, flags);
-       d40_term_all(chan);
-       spin_unlock_irqrestore(&chan->lock, flags);
-
-       return ret;
-}
-
 static dma_cookie_t d40_tx_submit(struct dma_async_tx_descriptor *tx)
 {
        struct d40_chan *d40c = container_of(tx->chan,
@@ -1232,20 +1318,6 @@ static dma_cookie_t d40_tx_submit(struct dma_async_tx_descriptor *tx)
 
 static int d40_start(struct d40_chan *d40c)
 {
-       if (d40c->base->rev == 0) {
-               int err;
-
-               if (chan_is_logical(d40c)) {
-                       err = d40_channel_execute_command(d40c,
-                                                         D40_DMA_SUSPEND_REQ);
-                       if (err)
-                               return err;
-               }
-       }
-
-       if (chan_is_logical(d40c))
-               d40_config_set_event(d40c, true);
-
        return d40_channel_execute_command(d40c, D40_DMA_RUN);
 }
 
@@ -1258,10 +1330,10 @@ static struct d40_desc *d40_queue_start(struct d40_chan *d40c)
        d40d = d40_first_queued(d40c);
 
        if (d40d != NULL) {
-               if (!d40c->busy)
+               if (!d40c->busy) {
                        d40c->busy = true;
-
-               pm_runtime_get_sync(d40c->base->dev);
+                       pm_runtime_get_sync(d40c->base->dev);
+               }
 
                /* Remove from queue */
                d40_desc_remove(d40d);
@@ -1388,8 +1460,8 @@ static void dma_tasklet(unsigned long data)
 
        return;
 
- err:
-       /* Rescue manoeuvre if receiving double interrupts */
+err:
+       /* Rescue manouver if receiving double interrupts */
        if (d40c->pending_tx > 0)
                d40c->pending_tx--;
        spin_unlock_irqrestore(&d40c->lock, flags);
@@ -1770,7 +1842,6 @@ static int d40_config_memcpy(struct d40_chan *d40c)
        return 0;
 }
 
-
 static int d40_free_dma(struct d40_chan *d40c)
 {
 
@@ -1806,43 +1877,18 @@ static int d40_free_dma(struct d40_chan *d40c)
        }
 
        pm_runtime_get_sync(d40c->base->dev);
-       res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
+       res = d40_channel_execute_command(d40c, D40_DMA_STOP);
        if (res) {
-               chan_err(d40c, "suspend failed\n");
+               chan_err(d40c, "stop failed\n");
                goto out;
        }
 
-       if (chan_is_logical(d40c)) {
-               /* Release logical channel, deactivate the event line */
+       d40_alloc_mask_free(phy, is_src, chan_is_logical(d40c) ? event : 0);
 
-               d40_config_set_event(d40c, false);
+       if (chan_is_logical(d40c))
                d40c->base->lookup_log_chans[d40c->log_num] = NULL;
-
-               /*
-                * Check if there are more logical allocation
-                * on this phy channel.
-                */
-               if (!d40_alloc_mask_free(phy, is_src, event)) {
-                       /* Resume the other logical channels if any */
-                       if (d40_chan_has_events(d40c)) {
-                               res = d40_channel_execute_command(d40c,
-                                                                 D40_DMA_RUN);
-                               if (res)
-                                       chan_err(d40c,
-                                               "Executing RUN command\n");
-                       }
-                       goto out;
-               }
-       } else {
-               (void) d40_alloc_mask_free(phy, is_src, 0);
-       }
-
-       /* Release physical channel */
-       res = d40_channel_execute_command(d40c, D40_DMA_STOP);
-       if (res) {
-               chan_err(d40c, "Failed to stop channel\n");
-               goto out;
-       }
+       else
+               d40c->base->lookup_phy_chans[phy->num] = NULL;
 
        if (d40c->busy) {
                pm_runtime_mark_last_busy(d40c->base->dev);
@@ -1852,7 +1898,6 @@ static int d40_free_dma(struct d40_chan *d40c)
        d40c->busy = false;
        d40c->phy_chan = NULL;
        d40c->configured = false;
-       d40c->base->lookup_phy_chans[phy->num] = NULL;
 out:
 
        pm_runtime_mark_last_busy(d40c->base->dev);
@@ -2371,6 +2416,31 @@ static void d40_issue_pending(struct dma_chan *chan)
        spin_unlock_irqrestore(&d40c->lock, flags);
 }
 
+static void d40_terminate_all(struct dma_chan *chan)
+{
+       unsigned long flags;
+       struct d40_chan *d40c = container_of(chan, struct d40_chan, chan);
+       int ret;
+
+       spin_lock_irqsave(&d40c->lock, flags);
+
+       pm_runtime_get_sync(d40c->base->dev);
+       ret = d40_channel_execute_command(d40c, D40_DMA_STOP);
+       if (ret)
+               chan_err(d40c, "Failed to stop channel\n");
+
+       d40_term_all(d40c);
+       pm_runtime_mark_last_busy(d40c->base->dev);
+       pm_runtime_put_autosuspend(d40c->base->dev);
+       if (d40c->busy) {
+               pm_runtime_mark_last_busy(d40c->base->dev);
+               pm_runtime_put_autosuspend(d40c->base->dev);
+       }
+       d40c->busy = false;
+
+       spin_unlock_irqrestore(&d40c->lock, flags);
+}
+
 static int
 dma40_config_to_halfchannel(struct d40_chan *d40c,
                            struct stedma40_half_channel_info *info,
@@ -2551,7 +2621,8 @@ static int d40_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
 
        switch (cmd) {
        case DMA_TERMINATE_ALL:
-               return d40_terminate_all(d40c);
+               d40_terminate_all(chan);
+               return 0;
        case DMA_PAUSE:
                return d40_pause(d40c);
        case DMA_RESUME:
@@ -2908,6 +2979,12 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
        dev_info(&pdev->dev, "hardware revision: %d @ 0x%x\n",
                 rev, res->start);
 
+       if (rev < 2) {
+               d40_err(&pdev->dev, "hardware revision: %d is not supported",
+                       rev);
+               goto failure;
+       }
+
        plat_data = pdev->dev.platform_data;
 
        /* Count the number of logical channels in use */
@@ -2998,6 +3075,7 @@ failure:
 
        if (base) {
                kfree(base->lcla_pool.alloc_map);
+               kfree(base->reg_val_backup_chan);
                kfree(base->lookup_log_chans);
                kfree(base->lookup_phy_chans);
                kfree(base->phy_res);
index 8d3d490..51e8e53 100644 (file)
@@ -62,8 +62,6 @@
 #define D40_SREG_ELEM_LOG_LIDX_MASK    (0xFF << D40_SREG_ELEM_LOG_LIDX_POS)
 
 /* Link register */
-#define D40_DEACTIVATE_EVENTLINE       0x0
-#define D40_ACTIVATE_EVENTLINE         0x1
 #define D40_EVENTLINE_POS(i)           (2 * i)
 #define D40_EVENTLINE_MASK(i)          (0x3 << D40_EVENTLINE_POS(i))