dmaengine: imx-sdma: support hdmi in sdma

The hdmi script already supported in sdma firmware. So add support hdmi
in sdma driver.

The design of hdmi script is different from common script such as sai.
There is no need to config buffer descriptor for HDMI. The cyclic
capability is achieved by the hdmi script. The slave config is so simple,
only config src_addr, dts_addr and direction DMA_TRANS_NONE.
Signed-off-by: Joy Zou <joy.zou@nxp.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/20221115093823.2879128-3-joy.zou@nxp.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/imx-sdma.c

@@ -954,7 +954,10 @@ static irqreturn_t sdma_int_handler(int irq, void *dev_id)
 		desc = sdmac->desc;
 		if (desc) {
 			if (sdmac->flags & IMX_DMA_SG_LOOP) {
-				sdma_update_channel_loop(sdmac);
+				if (sdmac->peripheral_type != IMX_DMATYPE_HDMI)
+					sdma_update_channel_loop(sdmac);
+				else
+					vchan_cyclic_callback(&desc->vd);
 			} else {
 				mxc_sdma_handle_channel_normal(sdmac);
 				vchan_cookie_complete(&desc->vd);
@@ -1074,6 +1077,10 @@ static int sdma_get_pc(struct sdma_channel *sdmac,
 		per_2_emi = sdma->script_addrs->sai_2_mcu_addr;
 		emi_2_per = sdma->script_addrs->mcu_2_sai_addr;
 		break;
+	case IMX_DMATYPE_HDMI:
+		emi_2_per = sdma->script_addrs->hdmi_dma_addr;
+		sdmac->is_ram_script = true;
+		break;
 	default:
 		dev_err(sdma->dev, "Unsupported transfer type %d\n",
 			peripheral_type);
@@ -1125,11 +1132,16 @@ static int sdma_load_context(struct sdma_channel *sdmac)
 	/* Send by context the event mask,base address for peripheral
 	 * and watermark level
 	 */
-	context->gReg[0] = sdmac->event_mask[1];
-	context->gReg[1] = sdmac->event_mask[0];
-	context->gReg[2] = sdmac->per_addr;
-	context->gReg[6] = sdmac->shp_addr;
-	context->gReg[7] = sdmac->watermark_level;
+	if (sdmac->peripheral_type == IMX_DMATYPE_HDMI) {
+		context->gReg[4] = sdmac->per_addr;
+		context->gReg[6] = sdmac->shp_addr;
+	} else {
+		context->gReg[0] = sdmac->event_mask[1];
+		context->gReg[1] = sdmac->event_mask[0];
+		context->gReg[2] = sdmac->per_addr;
+		context->gReg[6] = sdmac->shp_addr;
+		context->gReg[7] = sdmac->watermark_level;
+	}
 
 	bd0->mode.command = C0_SETDM;
 	bd0->mode.status = BD_DONE | BD_WRAP | BD_EXTD;
@@ -1513,7 +1525,7 @@ static struct sdma_desc *sdma_transfer_init(struct sdma_channel *sdmac,
 	desc->sdmac = sdmac;
 	desc->num_bd = bds;
 
-	if (sdma_alloc_bd(desc))
+	if (bds && sdma_alloc_bd(desc))
 		goto err_desc_out;
 
 	/* No slave_config called in MEMCPY case, so do here */
@@ -1678,13 +1690,16 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
 {
 	struct sdma_channel *sdmac = to_sdma_chan(chan);
 	struct sdma_engine *sdma = sdmac->sdma;
-	int num_periods = buf_len / period_len;
+	int num_periods = 0;
 	int channel = sdmac->channel;
 	int i = 0, buf = 0;
 	struct sdma_desc *desc;
 
 	dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);
 
+	if (sdmac->peripheral_type != IMX_DMATYPE_HDMI)
+		num_periods = buf_len / period_len;
+
 	sdma_config_write(chan, &sdmac->slave_config, direction);
 
 	desc = sdma_transfer_init(sdmac, direction, num_periods);
@@ -1701,6 +1716,9 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
 		goto err_bd_out;
 	}
 
+	if (sdmac->peripheral_type == IMX_DMATYPE_HDMI)
+		return vchan_tx_prep(&sdmac->vc, &desc->vd, flags);
+
 	while (buf < buf_len) {
 		struct sdma_buffer_descriptor *bd = &desc->bd[i];
 		int param;
@@ -1761,6 +1779,10 @@ static int sdma_config_write(struct dma_chan *chan,
 		sdmac->watermark_level |= (dmaengine_cfg->dst_maxburst << 16) &
 			SDMA_WATERMARK_LEVEL_HWML;
 		sdmac->word_size = dmaengine_cfg->dst_addr_width;
+	} else if (sdmac->peripheral_type == IMX_DMATYPE_HDMI) {
+		sdmac->per_address = dmaengine_cfg->dst_addr;
+		sdmac->per_address2 = dmaengine_cfg->src_addr;
+		sdmac->watermark_level = 0;
 	} else {
 		sdmac->per_address = dmaengine_cfg->dst_addr;
 		sdmac->watermark_level = dmaengine_cfg->dst_maxburst *

include/linux/dma/imx-dma.h

@@ -40,6 +40,7 @@ enum sdma_peripheral_type {
 	IMX_DMATYPE_ASRC_SP,	/* Shared ASRC */
 	IMX_DMATYPE_SAI,	/* SAI */
 	IMX_DMATYPE_MULTI_SAI,	/* MULTI FIFOs For Audio */
+	IMX_DMATYPE_HDMI,       /* HDMI Audio */
 };
 
 enum imx_dma_prio {