target/linux/mediatek/patches-5.4/999-2366-fix-SPIM-dma-buffer-not-aligned.patch

From 475f064022a716bda4574406d8365627c3bcf131 Mon Sep 17 00:00:00 2001
From: Sam Shih <sam.shih@mediatek.com>
Date: Fri, 2 Jun 2023 13:06:19 +0800
Subject: [PATCH] 
 [spi-and-storage][999-2366-fix-SPIM-dma-buffer-not-aligned.patch]

---
 drivers/spi/spi-mt65xx.c | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
index 05697e1d1..2883dc908 100644
--- a/drivers/spi/spi-mt65xx.c
+++ b/drivers/spi/spi-mt65xx.c
@@ -184,7 +184,7 @@ static const struct mtk_spi_compatible mt8183_compat = {
  */
 static const struct mtk_chip_config mtk_default_chip_info = {
 	.sample_sel = 0,
-	.get_tick_dly = 0,
+	.get_tick_dly = 1,
 };
 
 static const struct of_device_id mtk_spi_of_match[] = {
@@ -731,8 +731,11 @@ static int mtk_spi_mem_adjust_op_size(struct spi_mem *mem,
 
 	if (op->data.dir != SPI_MEM_NO_DATA) {
 		opcode_len = 1 + op->addr.nbytes + op->dummy.nbytes;
-		if (opcode_len + op->data.nbytes > MTK_SPI_IPM_PACKET_SIZE)
+		if (opcode_len + op->data.nbytes > MTK_SPI_IPM_PACKET_SIZE) {
 			op->data.nbytes = MTK_SPI_IPM_PACKET_SIZE -opcode_len;
+			/* force data buffer dma-aligned. */
+			op->data.nbytes -= op->data.nbytes % 4;
+		}
 	}
 
 	return 0;
@@ -759,10 +762,6 @@ static bool mtk_spi_mem_supports_op(struct spi_mem *mem,
 			return false;
 	}
 
-	if (op->data.dir == SPI_MEM_DATA_IN &&
-	    !IS_ALIGNED((size_t)op->data.buf.in, 4))
-		return false;
-
 	return true;
 }
 
@@ -821,6 +820,7 @@ static int mtk_spi_mem_exec_op(struct spi_mem *mem,
 	struct mtk_spi *mdata = spi_master_get_devdata(mem->spi->master);
 	u32 reg_val, nio = 1, tx_size;
 	char *tx_tmp_buf;
+	char *rx_tmp_buf;
 	int ret = 0;
 
 	mdata->use_spimem = true;
@@ -915,10 +915,18 @@ static int mtk_spi_mem_exec_op(struct spi_mem *mem,
 	}
 
 	if (op->data.dir == SPI_MEM_DATA_IN) {
+		if(!IS_ALIGNED((size_t)op->data.buf.in, 4)) {
+			rx_tmp_buf = kzalloc(op->data.nbytes, GFP_KERNEL | GFP_DMA);
+			if (!rx_tmp_buf)
+				return -ENOMEM;
+		}
+		else
+			rx_tmp_buf = op->data.buf.in;
+
 		mdata->rx_dma = dma_map_single(mdata->dev,
-					       op->data.buf.in,
-					       op->data.nbytes,
-					       DMA_FROM_DEVICE);
+						   rx_tmp_buf,
+						   op->data.nbytes,
+						   DMA_FROM_DEVICE);
 		if (dma_mapping_error(mdata->dev, mdata->rx_dma)) {
 			ret = -ENOMEM;
 			goto unmap_tx_dma;
@@ -948,9 +956,14 @@ static int mtk_spi_mem_exec_op(struct spi_mem *mem,
 	writel(reg_val, mdata->base + SPI_CMD_REG);
 
 unmap_rx_dma:
-	if (op->data.dir == SPI_MEM_DATA_IN)
+	if (op->data.dir == SPI_MEM_DATA_IN) {
+		if(!IS_ALIGNED((size_t)op->data.buf.in, 4)) {
+			memcpy(op->data.buf.in, rx_tmp_buf, op->data.nbytes);
+			kfree(rx_tmp_buf);
+		}
 		dma_unmap_single(mdata->dev, mdata->rx_dma,
 				 op->data.nbytes, DMA_FROM_DEVICE);
+	}
 unmap_tx_dma:
 	dma_unmap_single(mdata->dev, mdata->tx_dma,
 			 tx_size, DMA_TO_DEVICE);
-- 
2.34.1