[PATCH 04/11] wifi: mt76: mt7921: add MT7902e DMA layout support

[sean.wang@kernel.org]

From: Sean Wang <sean.wang@mediatek.com>

Add MT7902 PCIe specific DMA layout overrides for MCU TXQ index, RX ring
size, and MCU_WA usage. Common layout remains the default for other chips.

This is a prerequisite patch before enabling MT7902 PCIe support.

Co-developed-by: Xiong Huang <xiong.huang@mediatek.com>
Signed-off-by: Xiong Huang <xiong.huang@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
 .../wireless/mediatek/mt76/mt7921/mt7921.h    | 14 +++++++
 .../net/wireless/mediatek/mt76/mt7921/pci.c   | 41 +++++++++++++++----
 2 files changed, 46 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h b/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h
index ad92af98e314..64f60c4fc60c 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h
@@ -17,6 +17,9 @@
 #define MT7921_RX_MCU_RING_SIZE		8
 #define MT7921_RX_MCU_WA_RING_SIZE	512
 
+/* MT7902 Rx Ring0 is for both Rx Event and Tx Done Event */
+#define MT7902_RX_MCU_RING_SIZE		512
+
 #define MT7921_EEPROM_SIZE		3584
 #define MT7921_TOKEN_SIZE		8192
 
@@ -119,6 +122,17 @@ enum mt7921_rxq_id {
 	MT7921_RXQ_MCU_WM = 0,
 };
 
+/* MT7902 assigns its MCU-WM TXQ at index 15 */
+enum mt7902_txq_id {
+	MT7902_TXQ_MCU_WM = 15,
+};
+
+struct mt7921_dma_layout {
+	u8 mcu_wm_txq;
+	u16 mcu_rxdone_ring_size;
+	bool has_mcu_wa;
+};
+
 enum {
 	MT7921_CLC_POWER,
 	MT7921_CLC_CHAN,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
index 5f857a21f362..6bb3c6a1cf6a 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
@@ -167,8 +167,29 @@ static u32 mt7921_rmw(struct mt76_dev *mdev, u32 offset, u32 mask, u32 val)
 
 static int mt7921_dma_init(struct mt792x_dev *dev)
 {
+	struct mt7921_dma_layout layout = {
+		/* General case: MT7921 / MT7922 /MT7920 */
+		.mcu_wm_txq            = MT7921_TXQ_MCU_WM,
+		.mcu_rxdone_ring_size  = MT7921_RX_MCU_RING_SIZE,
+		.has_mcu_wa            = true,
+	};
+	bool is_mt7902;
 	int ret;
 
+	is_mt7902 = mt7921_l1_rr(dev, MT_HW_CHIPID) == 0x7902;
+
+	/*
+	 * MT7902 special case:
+	 *   - MCU-WM TXQ uses index 15
+	 *   - RX Ring0 is larger and shared for event/TX-done
+	 *   - MT7902 does not use the MCU_WA ring
+	 */
+	if (is_mt7902) {
+		layout.mcu_wm_txq           = MT7902_TXQ_MCU_WM;
+		layout.mcu_rxdone_ring_size = MT7902_RX_MCU_RING_SIZE;
+		layout.has_mcu_wa           = false;
+	}
+
 	mt76_dma_attach(&dev->mt76);
 
 	ret = mt792x_dma_disable(dev, true);
@@ -185,7 +206,7 @@ static int mt7921_dma_init(struct mt792x_dev *dev)
 	mt76_wr(dev, MT_WFDMA0_TX_RING0_EXT_CTRL, 0x4);
 
 	/* command to WM */
-	ret = mt76_init_mcu_queue(&dev->mt76, MT_MCUQ_WM, MT7921_TXQ_MCU_WM,
+	ret = mt76_init_mcu_queue(&dev->mt76, MT_MCUQ_WM, layout.mcu_wm_txq,
 				  MT7921_TX_MCU_RING_SIZE, MT_TX_RING_BASE);
 	if (ret)
 		return ret;
@@ -199,18 +220,20 @@ static int mt7921_dma_init(struct mt792x_dev *dev)
 	/* event from WM before firmware download */
 	ret = mt76_queue_alloc(dev, &dev->mt76.q_rx[MT_RXQ_MCU],
 			       MT7921_RXQ_MCU_WM,
-			       MT7921_RX_MCU_RING_SIZE,
+			       layout.mcu_rxdone_ring_size,
 			       MT_RX_BUF_SIZE, MT_RX_EVENT_RING_BASE);
 	if (ret)
 		return ret;
 
-	/* Change mcu queue after firmware download */
-	ret = mt76_queue_alloc(dev, &dev->mt76.q_rx[MT_RXQ_MCU_WA],
-			       MT7921_RXQ_MCU_WM,
-			       MT7921_RX_MCU_WA_RING_SIZE,
-			       MT_RX_BUF_SIZE, MT_WFDMA0(0x540));
-	if (ret)
-		return ret;
+	if (layout.has_mcu_wa) {
+		/* Change mcu queue after firmware download */
+		ret = mt76_queue_alloc(dev, &dev->mt76.q_rx[MT_RXQ_MCU_WA],
+				       MT7921_RXQ_MCU_WM,
+				       MT7921_RX_MCU_WA_RING_SIZE,
+				       MT_RX_BUF_SIZE, MT_WFDMA0(0x540));
+		if (ret)
+			return ret;
+	}
 
 	/* rx data */
 	ret = mt76_queue_alloc(dev, &dev->mt76.q_rx[MT_RXQ_MAIN],
-- 
2.43.0