dw-dma: change to use runtime_shared heap for lli buffer

The lli structs are used by both DSP and DMAC, allocate them from the
runtime_shared heap to avoid being corrupted by cache writing back.

This helps to fix a lot of DMA xrun issue according to the validation.

Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>

Author: keyonjie

src/drivers/dw/dma.c

@@ -437,9 +437,6 @@ static int dw_dma_stop(struct dma_chan_data *channel)
 		lli->ctrl_hi &= ~DW_CTLH_DONE(1);
 		lli++;
 	}
-
-	dcache_writeback_region(dw_chan->lli,
-				sizeof(struct dw_lli) * channel->desc_count);
 #endif
 
 	/* disable linear link position */
@@ -557,9 +554,9 @@ static int dw_dma_set_config(struct dma_chan_data *channel,
 		if (dw_chan->lli)
 			rfree(dw_chan->lli);
 
-		dw_chan->lli = rballoc_align(0, SOF_MEM_CAPS_RAM | SOF_MEM_CAPS_DMA,
-					sizeof(struct dw_lli) * channel->desc_count,
-					PLATFORM_DCACHE_ALIGN);
+		dw_chan->lli = rzalloc(SOF_MEM_ZONE_RUNTIME_SHARED, 0,
+				       SOF_MEM_CAPS_RAM | SOF_MEM_CAPS_DMA,
+				       sizeof(struct dw_lli) * channel->desc_count);
 		if (!dw_chan->lli) {
 			tr_err(&dwdma_tr, "dw_dma_set_config(): dma %d channel %d lli alloc failed",
 			       channel->dma->plat_data.id,
@@ -767,10 +764,6 @@ static int dw_dma_set_config(struct dma_chan_data *channel,
 #endif
 	}
 
-	/* write back descriptors so DMA engine can read them directly */
-	dcache_writeback_region(dw_chan->lli,
-				sizeof(struct dw_lli) * channel->desc_count);
-
 	channel->status = COMP_STATE_PREPARE;
 	dw_chan->lli_current = dw_chan->lli;
 
@@ -810,7 +803,7 @@ static void dw_dma_verify_transfer(struct dma_chan_data *channel,
 #if defined __ZEPHYR__
 	int i;
 #else
-	struct dw_lli *lli = platform_dw_dma_lli_get(dw_chan->lli_current);
+	struct dw_lli *lli = dw_chan->lli_current;
 #endif
 	switch (next->status) {
 	case DMA_CB_STATUS_END:
@@ -823,20 +816,14 @@ static void dw_dma_verify_transfer(struct dma_chan_data *channel,
 	 * sure the cache is coherent between DSP and DMAC.
 	 */
 #if defined __ZEPHYR__
-		dcache_invalidate_region(dw_chan->lli,
-					 sizeof(struct dw_lli) * channel->desc_count);
-
 		for (i = 0; i < channel->desc_count; i++)
 			dw_chan->lli[i].ctrl_hi &= ~DW_CTLH_DONE(1);
-
-		dcache_writeback_region(dw_chan->lli,
-					sizeof(struct dw_lli) * channel->desc_count);
 #else
 		while (lli->ctrl_hi & DW_CTLH_DONE(1)) {
 			lli->ctrl_hi &= ~DW_CTLH_DONE(1);
 			dw_chan->lli_current =
 				(struct dw_lli *)dw_chan->lli_current->llp;
-			lli = platform_dw_dma_lli_get(dw_chan->lli_current);
+			lli = dw_chan->lli_current;
 		}
 #endif
 		break;

src/platform/intel/cavs/include/cavs/drivers/dw-dma.h

@@ -85,11 +85,6 @@ static inline void platform_dw_dma_llp_disable(struct dma *dma,
 		   shim_read(DW_CHLLPC(dma, chan)) & ~SHIM_GPDMA_CHLLPC_EN);
 }
 
-static inline struct dw_lli *platform_dw_dma_lli_get(struct dw_lli *lli)
-{
-	return cache_to_uncache(lli);
-}
-
 #endif /* __CAVS_LIB_DW_DMA_H__ */
 
 #else