[PATCH v6 2/4] dmaengine: mmp_pdma: refactor DRCMR access with helper function

[Troy Mitchell]

From: Guodong Xu <guodong at riscstar.com>

Refactor the DRCMR macro into a helper function mmp_pdma_get_drcmr()
to support variable extended DRCMR base addresses across different PDMA
implementations, such as SpacemiT K3.

Signed-off-by: Guodong Xu <guodong at riscstar.com>
Signed-off-by: Troy Mitchell <troy.mitchell at linux.spacemit.com>
---
 drivers/dma/mmp_pdma.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c
index d12e729ee12c..6112369006ee 100644
--- a/drivers/dma/mmp_pdma.c
+++ b/drivers/dma/mmp_pdma.c
@@ -51,7 +51,9 @@
 #define DCSR_CMPST	BIT(10)	/* The Descriptor Compare Status */
 #define DCSR_EORINTR	BIT(9)	/* The end of Receive */
 
-#define DRCMR(n)	((((n) < 64) ? 0x0100 : 0x1100) + (((n) & 0x3f) << 2))
+#define DRCMR_BASE		0x0100
+#define DRCMR_EXT_BASE_DEFAULT	0x1100
+#define DRCMR_REQ_LIMIT		64
 #define DRCMR_MAPVLD	BIT(7)	/* Map Valid (read / write) */
 #define DRCMR_CHLNUM	0x1f	/* mask for Channel Number (read / write) */
 
@@ -154,6 +156,7 @@ struct mmp_pdma_phy {
  * @run_bits:   Control bits in DCSR register for channel start/stop
  * @dma_width:  DMA addressing width in bits (32 or 64). Determines the
  *              DMA mask capability of the controller hardware.
+ * @drcmr_ext_base: Base DRCMR address for extended requests
  */
 struct mmp_pdma_ops {
 	/* Hardware Register Operations */
@@ -174,6 +177,7 @@ struct mmp_pdma_ops {
 	/* Controller Configuration */
 	u32 run_bits;
 	u32 dma_width;
+	u32 drcmr_ext_base;
 };
 
 struct mmp_pdma_device {
@@ -195,6 +199,13 @@ struct mmp_pdma_device {
 #define to_mmp_pdma_dev(dmadev)					\
 	container_of(dmadev, struct mmp_pdma_device, device)
 
+static u32 mmp_pdma_get_drcmr(struct mmp_pdma_device *pdev, u32 drcmr)
+{
+	if (drcmr < DRCMR_REQ_LIMIT)
+		return DRCMR_BASE + (drcmr << 2);
+	return pdev->ops->drcmr_ext_base + ((drcmr - DRCMR_REQ_LIMIT) << 2);
+}
+
 /* For 32-bit PDMA */
 static void write_next_addr_32(struct mmp_pdma_phy *phy, dma_addr_t addr)
 {
@@ -301,7 +312,7 @@ static void enable_chan(struct mmp_pdma_phy *phy)
 
 	pdev = to_mmp_pdma_dev(phy->vchan->chan.device);
 
-	reg = DRCMR(phy->vchan->drcmr);
+	reg = mmp_pdma_get_drcmr(pdev, phy->vchan->drcmr);
 	writel(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 
 	dalgn = readl(phy->base + DALGN);
@@ -437,7 +448,7 @@ static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan)
 		return;
 
 	/* clear the channel mapping in DRCMR */
-	reg = DRCMR(pchan->drcmr);
+	reg = mmp_pdma_get_drcmr(pdev, pchan->drcmr);
 	writel(0, pchan->phy->base + reg);
 
 	spin_lock_irqsave(&pdev->phy_lock, flags);
@@ -1179,6 +1190,7 @@ static const struct mmp_pdma_ops marvell_pdma_v1_ops = {
 	.get_desc_dst_addr = get_desc_dst_addr_32,
 	.run_bits = (DCSR_RUN),
 	.dma_width = 32,
+	.drcmr_ext_base = DRCMR_EXT_BASE_DEFAULT,
 };
 
 static const struct mmp_pdma_ops spacemit_k1_pdma_ops = {
@@ -1192,6 +1204,7 @@ static const struct mmp_pdma_ops spacemit_k1_pdma_ops = {
 	.get_desc_dst_addr = get_desc_dst_addr_64,
 	.run_bits = (DCSR_RUN | DCSR_LPAEEN),
 	.dma_width = 64,
+	.drcmr_ext_base = DRCMR_EXT_BASE_DEFAULT,
 };
 
 static const struct of_device_id mmp_pdma_dt_ids[] = {

-- 
2.54.0