diff options
| -rw-r--r-- | drivers/dma/ste_dma40.c | 63 |
1 files changed, 46 insertions, 17 deletions
diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c index 52013ed4b442..42c88fc28815 100644 --- a/drivers/dma/ste_dma40.c +++ b/drivers/dma/ste_dma40.c @@ -303,6 +303,11 @@ struct d40_reg_val { unsigned int val; }; +static struct device *chan2dev(struct d40_chan *d40c) +{ + return &d40c->chan.dev->device; +} + static int d40_pool_lli_alloc(struct d40_desc *d40d, int lli_len, bool is_log) { @@ -701,17 +706,46 @@ static void d40_term_all(struct d40_chan *d40c) d40c->busy = false; } +static void __d40_config_set_event(struct d40_chan *d40c, bool enable, + u32 event, int reg) +{ + void __iomem *addr = d40c->base->virtbase + D40_DREG_PCBASE + + d40c->phy_chan->num * D40_DREG_PCDELTA + reg; + int tries; + + if (!enable) { + writel((D40_DEACTIVATE_EVENTLINE << D40_EVENTLINE_POS(event)) + | ~D40_EVENTLINE_MASK(event), addr); + return; + } + + /* + * 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); + + 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); + + WARN_ON(!tries); +} + static void d40_config_set_event(struct d40_chan *d40c, bool do_enable) { - u32 val; unsigned long flags; - /* Notice, that disable requires the physical channel to be stopped */ - if (do_enable) - val = D40_ACTIVATE_EVENTLINE; - else - val = D40_DEACTIVATE_EVENTLINE; - spin_lock_irqsave(&d40c->phy_chan->lock, flags); /* Enable event line connected to device (or memcpy) */ @@ -719,20 +753,15 @@ static void d40_config_set_event(struct d40_chan *d40c, bool do_enable) (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_PERIPH)) { u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.src_dev_type); - writel((val << D40_EVENTLINE_POS(event)) | - ~D40_EVENTLINE_MASK(event), - d40c->base->virtbase + D40_DREG_PCBASE + - d40c->phy_chan->num * D40_DREG_PCDELTA + - D40_CHAN_REG_SSLNK); + __d40_config_set_event(d40c, do_enable, 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); - writel((val << D40_EVENTLINE_POS(event)) | - ~D40_EVENTLINE_MASK(event), - d40c->base->virtbase + D40_DREG_PCBASE + - d40c->phy_chan->num * D40_DREG_PCDELTA + - D40_CHAN_REG_SDLNK); + __d40_config_set_event(d40c, do_enable, event, + D40_CHAN_REG_SDLNK); } spin_unlock_irqrestore(&d40c->phy_chan->lock, flags); |