mmc: mediatek: support 24bits segment size

MSDC IP which support 64G DRAM will support 24bits BDMA buffer length,
so add support it.

Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/mtk-sd.c

@@ -328,6 +328,7 @@ struct mt_bdma_desc {
 	u32 ptr;
 	u32 bd_data_len;
 #define BDMA_DESC_BUFLEN	(0xffff) /* bit0 ~ bit15 */
+#define BDMA_DESC_BUFLEN_EXT	(0xffffff) /* bit0 ~ bit23 */
 };
 
 struct msdc_dma {
@@ -641,8 +642,14 @@ static inline void msdc_dma_setup(struct msdc_host *host, struct msdc_dma *dma,
 			bd[j].bd_info |= (upper_32_bits(dma_address) & 0xf)
 					 << 28;
 		}
-		bd[j].bd_data_len &= ~BDMA_DESC_BUFLEN;
-		bd[j].bd_data_len |= (dma_len & BDMA_DESC_BUFLEN);
+
+		if (host->dev_comp->support_64g) {
+			bd[j].bd_data_len &= ~BDMA_DESC_BUFLEN_EXT;
+			bd[j].bd_data_len |= (dma_len & BDMA_DESC_BUFLEN_EXT);
+		} else {
+			bd[j].bd_data_len &= ~BDMA_DESC_BUFLEN;
+			bd[j].bd_data_len |= (dma_len & BDMA_DESC_BUFLEN);
+		}
 
 		if (j == data->sg_count - 1) /* the last bd */
 			bd[j].bd_info |= BDMA_DESC_EOL;
@@ -2277,7 +2284,10 @@ static int msdc_drv_probe(struct platform_device *pdev)
 	mmc->caps |= MMC_CAP_ERASE | MMC_CAP_CMD23;
 	/* MMC core transfer sizes tunable parameters */
 	mmc->max_segs = MAX_BD_NUM;
-	mmc->max_seg_size = BDMA_DESC_BUFLEN;
+	if (host->dev_comp->support_64g)
+		mmc->max_seg_size = BDMA_DESC_BUFLEN_EXT;
+	else
+		mmc->max_seg_size = BDMA_DESC_BUFLEN;
 	mmc->max_blk_size = 2048;
 	mmc->max_req_size = 512 * 1024;
 	mmc->max_blk_count = mmc->max_req_size / 512;