dmaengine: dw: add support of iDMA 32-bit hardware

iDMA 32-bit is Intel designed DMA controller that behaves like Synopsys
Designware DMA. This patch adds a support of the new Intel hardware.

Due to iDMA 32-bit has no autoconfiguration the platform code must
provide a platform data to dw_dma_probe().

By default full FIFO (1024 bytes) is assigned to channel 0. Here we
slice FIFO on equal parts between channels for iDMA 32-bit case.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 0186d67..e500950 100644 (file)
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -138,16 +138,32 @@ static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
        dwc->descs_allocated--;
 }
 
-static void dwc_initialize(struct dw_dma_chan *dwc)
+static void dwc_initialize_chan_idma32(struct dw_dma_chan *dwc)
+{
+       u32 cfghi = 0;
+       u32 cfglo = 0;
+
+       /* Set default burst alignment */
+       cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN;
+
+       /* Low 4 bits of the request lines */
+       cfghi |= IDMA32C_CFGH_DST_PER(dwc->dws.dst_id & 0xf);
+       cfghi |= IDMA32C_CFGH_SRC_PER(dwc->dws.src_id & 0xf);
+
+       /* Request line extension (2 bits) */
+       cfghi |= IDMA32C_CFGH_DST_PER_EXT(dwc->dws.dst_id >> 4 & 0x3);
+       cfghi |= IDMA32C_CFGH_SRC_PER_EXT(dwc->dws.src_id >> 4 & 0x3);
+
+       channel_writel(dwc, CFG_LO, cfglo);
+       channel_writel(dwc, CFG_HI, cfghi);
+}
+
+static void dwc_initialize_chan_dw(struct dw_dma_chan *dwc)
 {
-       struct dw_dma *dw = to_dw_dma(dwc->chan.device);
        u32 cfghi = DWC_CFGH_FIFO_MODE;
        u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority);
        bool hs_polarity = dwc->dws.hs_polarity;
 
-       if (test_bit(DW_DMA_IS_INITIALIZED, &dwc->flags))
-               return;
-
        cfghi |= DWC_CFGH_DST_PER(dwc->dws.dst_id);
        cfghi |= DWC_CFGH_SRC_PER(dwc->dws.src_id);
 
@@ -156,6 +172,19 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
 
        channel_writel(dwc, CFG_LO, cfglo);
        channel_writel(dwc, CFG_HI, cfghi);
+}
+
+static void dwc_initialize(struct dw_dma_chan *dwc)
+{
+       struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+
+       if (test_bit(DW_DMA_IS_INITIALIZED, &dwc->flags))
+               return;
+
+       if (dw->pdata->is_idma32)
+               dwc_initialize_chan_idma32(dwc);
+       else
+               dwc_initialize_chan_dw(dwc);
 
        /* Enable interrupts */
        channel_set_bit(dw, MASK.XFER, dwc->mask);
@@ -187,8 +216,13 @@ static inline void dwc_chan_disable(struct dw_dma *dw, struct dw_dma_chan *dwc)
 static u32 bytes2block(struct dw_dma_chan *dwc, size_t bytes,
                          unsigned int width, size_t *len)
 {
+       struct dw_dma *dw = to_dw_dma(dwc->chan.device);
        u32 block;
 
+       /* Always in bytes for iDMA 32-bit */
+       if (dw->pdata->is_idma32)
+               width = 0;
+
        if ((bytes >> width) > dwc->block_size) {
                block = dwc->block_size;
                *len = block << width;
@@ -202,6 +236,11 @@ static u32 bytes2block(struct dw_dma_chan *dwc, size_t bytes,
 
 static size_t block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
 {
+       struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+
+       if (dw->pdata->is_idma32)
+               return IDMA32C_CTLH_BLOCK_TS(block);
+
        return DWC_CTLH_BLOCK_TS(block) << width;
 }
 
@@ -915,14 +954,16 @@ static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 {
        struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
        struct dma_slave_config *sc = &dwc->dma_sconfig;
+       struct dw_dma *dw = to_dw_dma(chan->device);
        /*
         * Fix sconfig's burst size according to dw_dmac. We need to convert
         * them as:
         * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.
         *
         * NOTE: burst size 2 is not supported by DesignWare controller.
+        *       iDMA 32-bit supports it.
         */
-       u32 s = 2;
+       u32 s = dw->pdata->is_idma32 ? 1 : 2;
 
        /* Check if chan will be configured for slave transfers */
        if (!is_slave_direction(sconfig->direction))
@@ -937,12 +978,19 @@ static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
        return 0;
 }
 
-static void dwc_chan_pause(struct dw_dma_chan *dwc)
+static void dwc_chan_pause(struct dw_dma_chan *dwc, bool drain)
 {
+       struct dw_dma *dw = to_dw_dma(dwc->chan.device);
        unsigned int            count = 20;     /* timeout iterations */
        u32                     cfglo;
 
        cfglo = channel_readl(dwc, CFG_LO);
+       if (dw->pdata->is_idma32) {
+               if (drain)
+                       cfglo |= IDMA32C_CFGL_CH_DRAIN;
+               else
+                       cfglo &= ~IDMA32C_CFGL_CH_DRAIN;
+       }
        channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
        while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--)
                udelay(2);
@@ -956,7 +1004,7 @@ static int dwc_pause(struct dma_chan *chan)
        unsigned long           flags;
 
        spin_lock_irqsave(&dwc->lock, flags);
-       dwc_chan_pause(dwc);
+       dwc_chan_pause(dwc, false);
        spin_unlock_irqrestore(&dwc->lock, flags);
 
        return 0;
@@ -998,6 +1046,8 @@ static int dwc_terminate_all(struct dma_chan *chan)
 
        clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
 
+       dwc_chan_pause(dwc, true);
+
        dwc_chan_disable(dw, dwc);
 
        dwc_chan_resume(dwc);
@@ -1090,6 +1140,32 @@ static void dwc_issue_pending(struct dma_chan *chan)
 
 /*----------------------------------------------------------------------*/
 
+/*
+ * Program FIFO size of channels.
+ *
+ * By default full FIFO (1024 bytes) is assigned to channel 0. Here we
+ * slice FIFO on equal parts between channels.
+ */
+static void idma32_fifo_partition(struct dw_dma *dw)
+{
+       u64 value = IDMA32C_FP_PSIZE_CH0(128) | IDMA32C_FP_PSIZE_CH1(128) |
+                   IDMA32C_FP_UPDATE;
+       u64 fifo_partition = 0;
+
+       if (!dw->pdata->is_idma32)
+               return;
+
+       /* Fill FIFO_PARTITION low bits (Channels 0..1, 4..5) */
+       fifo_partition |= value << 0;
+
+       /* Fill FIFO_PARTITION high bits (Channels 2..3, 6..7) */
+       fifo_partition |= value << 32;
+
+       /* Program FIFO Partition registers - 128 bytes for each channel */
+       idma32_writeq(dw, FIFO_PARTITION1, fifo_partition);
+       idma32_writeq(dw, FIFO_PARTITION0, fifo_partition);
+}
+
 static void dw_dma_off(struct dw_dma *dw)
 {
        unsigned int i;
@@ -1509,8 +1585,13 @@ int dw_dma_probe(struct dw_dma_chip *chip)
        /* Force dma off, just in case */
        dw_dma_off(dw);
 
+       idma32_fifo_partition(dw);
+
        /* Device and instance ID for IRQ and DMA pool */
-       snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", chip->id);
+       if (pdata->is_idma32)
+               snprintf(dw->name, sizeof(dw->name), "idma32:dmac%d", chip->id);
+       else
+               snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", chip->id);
 
        /* Create a pool of consistent memory blocks for hardware descriptors */
        dw->desc_pool = dmam_pool_create(dw->name, chip->dev,
@@ -1673,6 +1754,8 @@ int dw_dma_enable(struct dw_dma_chip *chip)
 {
        struct dw_dma *dw = chip->dw;
 
+       idma32_fifo_partition(dw);
+
        dw_dma_on(dw);
        return 0;
 }

diff --git a/include/linux/platform_data/dma-dw.h b/include/linux/platform_data/dma-dw.h
index e69e415..896cb71 100644 (file)
--- a/include/linux/platform_data/dma-dw.h
+++ b/include/linux/platform_data/dma-dw.h
@@ -41,6 +41,7 @@ struct dw_dma_slave {
  * @is_private: The device channels should be marked as private and not for
  *     by the general purpose DMA channel allocator.
  * @is_memcpy: The device channels do support memory-to-memory transfers.
+ * @is_idma32: The type of the DMA controller is iDMA32
  * @chan_allocation_order: Allocate channels starting from 0 or 7
  * @chan_priority: Set channel priority increasing from 0 to 7 or 7 to 0.
  * @block_size: Maximum block size supported by the controller
@@ -53,6 +54,7 @@ struct dw_dma_platform_data {
        unsigned int    nr_channels;
        bool            is_private;
        bool            is_memcpy;
+       bool            is_idma32;
 #define CHAN_ALLOCATION_ASCENDING      0       /* zero to seven */
 #define CHAN_ALLOCATION_DESCENDING     1       /* seven to zero */
        unsigned char   chan_allocation_order;