0113-MIPS-lantiq-dma-make-a-burst-length-configurable-in-.patch

From 6615eeb39f7a110a196f20acbfb3a017da4d75d2 Mon Sep 17 00:00:00 2001
From: Aleksander Jan Bajkowski <olek2@wp.pl>
Date: Fri, 14 May 2021 21:25:08 +0200
Subject: [PATCH 4/5] MIPS: lantiq: dma: make a burst length configurable in
 drivers

Make a burst length configurable in drivers.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
---
 .../include/asm/mach-lantiq/xway/xway_dma.h   |  2 +-
 arch/mips/lantiq/xway/dma.c                   | 38 ++++++++++++++++---
 2 files changed, 34 insertions(+), 6 deletions(-)

--- a/arch/mips/include/asm/mach-lantiq/xway/xway_dma.h
+++ b/arch/mips/include/asm/mach-lantiq/xway/xway_dma.h
@@ -45,6 +45,6 @@ extern void ltq_dma_close(struct ltq_dma
 extern void ltq_dma_alloc_tx(struct ltq_dma_channel *ch);
 extern void ltq_dma_alloc_rx(struct ltq_dma_channel *ch);
 extern void ltq_dma_free(struct ltq_dma_channel *ch);
-extern void ltq_dma_init_port(int p);
+extern void ltq_dma_init_port(int p, int tx_burst, int rx_burst);
 
 #endif
--- a/arch/mips/lantiq/xway/dma.c
+++ b/arch/mips/lantiq/xway/dma.c
@@ -181,7 +181,7 @@ ltq_dma_free(struct ltq_dma_channel *ch)
 EXPORT_SYMBOL_GPL(ltq_dma_free);
 
 void
-ltq_dma_init_port(int p)
+ltq_dma_init_port(int p, int tx_burst, int rx_burst)
 {
 	ltq_dma_w32(p, LTQ_DMA_PS);
 	switch (p) {
@@ -190,16 +190,44 @@ ltq_dma_init_port(int p)
 		 * Tell the DMA engine to swap the endianness of data frames and
 		 * drop packets if the channel arbitration fails.
 		 */
-		ltq_dma_w32_mask(0, DMA_ETOP_ENDIANNESS | DMA_PDEN,
+		ltq_dma_w32_mask(0, (DMA_ETOP_ENDIANNESS | DMA_PDEN),
 			LTQ_DMA_PCTRL);
 		break;
 
-	case DMA_PORT_DEU:
-		ltq_dma_w32((DMA_PCTRL_2W_BURST << DMA_TX_BURST_SHIFT) |
-			(DMA_PCTRL_2W_BURST << DMA_RX_BURST_SHIFT),
+	default:
+		break;
+	}
+
+	switch (rx_burst) {
+	case 8:
+		ltq_dma_w32_mask(0x0c, (DMA_PCTRL_8W_BURST << DMA_RX_BURST_SHIFT),
 			LTQ_DMA_PCTRL);
 		break;
+	case 4:
+		ltq_dma_w32_mask(0x0c, (DMA_PCTRL_4W_BURST << DMA_RX_BURST_SHIFT),
+			LTQ_DMA_PCTRL);
+		break;
+	case 2:
+		ltq_dma_w32_mask(0x0c, (DMA_PCTRL_2W_BURST << DMA_RX_BURST_SHIFT),
+			LTQ_DMA_PCTRL);
+		break;
+	default:
+		break;
+	}
 
+	switch (tx_burst) {
+	case 8:
+		ltq_dma_w32_mask(0x30, (DMA_PCTRL_8W_BURST << DMA_TX_BURST_SHIFT),
+			LTQ_DMA_PCTRL);
+		break;
+	case 4:
+		ltq_dma_w32_mask(0x30, (DMA_PCTRL_4W_BURST << DMA_TX_BURST_SHIFT),
+			LTQ_DMA_PCTRL);
+		break;
+	case 2:
+		ltq_dma_w32_mask(0x30, (DMA_PCTRL_2W_BURST << DMA_TX_BURST_SHIFT),
+			LTQ_DMA_PCTRL);
+		break;
 	default:
 		break;
 	}