[PATCH 04/18] wifi: mt76: mt7925: add MT7927 DMA ring layout, IRQ map, and prefetch
Javier Tia
floss at jetm.me
Fri Mar 6 16:33:23 PST 2026
MT7927 uses different DMA ring indices than MT7925:
- RX MCU events: ring 6 (MT7925 uses ring 0)
- RX data: ring 4 (MT7925 uses ring 2)
- RX auxiliary: ring 7 (management frames)
- TX rings are identical
Add mt7927_dma_init() with the correct ring allocation, a dedicated
mt7927_irq_map with matching interrupt enable bits (BIT(12), BIT(14),
BIT(15) for RX rings 4, 6, 7), and MT7927 packed prefetch register
configuration in mt792x_dma_prefetch().
The DMA init performs a controlled SET_OWN/CLR_OWN sequence after CBTOP
and CBInfra initialization, since CLR_OWN triggers the ROM to initialize
WFDMA.
Ring layout and prefetch values derived from Loong0x00's
reverse-engineered MT7927 driver.
Tested-by: Marcin FM <marcin at lgic.pl>
Tested-by: Cristian-Florin Radoi <radoi.chris at gmail.com>
Tested-by: George Salukvadze <giosal90 at gmail.com>
Tested-by: Evgeny Kapusta <3193631 at gmail.com>
Tested-by: Samu Toljamo <samu.toljamo at gmail.com>
Tested-by: Ariel Rosenfeld <ariel.rosenfeld.750 at gmail.com>
Tested-by: Chapuis Dario <chapuisdario4 at gmail.com>
Tested-by: Thibaut François <tibo at humeurlibre.fr>
Tested-by: 张旭涵 <Loong.0x00 at gmail.com>
Signed-off-by: Javier Tia <floss at jetm.me>
---
drivers/net/wireless/mediatek/mt76/mt7925/mt7925.h | 7 ++
drivers/net/wireless/mediatek/mt76/mt7925/pci.c | 131 ++++++++++++++++++++-
drivers/net/wireless/mediatek/mt76/mt792x_dma.c | 18 ++-
drivers/net/wireless/mediatek/mt76/mt792x_regs.h | 10 ++
4 files changed, 163 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/mt7925.h b/drivers/net/wireless/mediatek/mt76/mt7925/mt7925.h
index 6b9bf1b89032..ba3d2c4de4ce 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/mt7925.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/mt7925.h
@@ -126,6 +126,13 @@ enum mt7925_rxq_id {
MT7925_RXQ_MCU_WM2, /* for tx done */
};
+/* MT7927 uses different RX ring indices than MT7925 */
+enum mt7927_rxq_id {
+ MT7927_RXQ_BAND0 = 4,
+ MT7927_RXQ_MCU_WM = 6,
+ MT7927_RXQ_DATA2 = 7,
+};
+
enum {
MODE_OPEN = 0,
MODE_SHARED = 1,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/pci.c b/drivers/net/wireless/mediatek/mt76/mt7925/pci.c
index c16ec05c5601..ca9ccfe9975c 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/pci.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/pci.c
@@ -324,6 +324,127 @@ static void mt7927_cbtop_remap(struct mt792x_dev *dev)
mt76_rr(dev, MT_CBINFRA_MISC0_REMAP_WF);
}
+static int mt7927_dma_init(struct mt792x_dev *dev)
+{
+ int ret;
+
+ mt76_dma_attach(&dev->mt76);
+
+ /* Do SET_OWN -> CLR_OWN now that CBTOP and CBInfra are ready.
+ * CLR_OWN triggers the ROM to initialize WFDMA properly. */
+ ret = mt792xe_mcu_fw_pmctrl(dev);
+ if (ret)
+ return ret;
+
+ ret = __mt792xe_mcu_drv_pmctrl(dev);
+ if (ret)
+ return ret;
+
+ /* Clear pending interrupts from previous state */
+ mt76_wr(dev, MT_WFDMA0_HOST_INT_STA, ~0);
+
+ /* Disable DMA */
+ mt76_clear(dev, MT_WFDMA0_GLO_CFG,
+ MT_WFDMA0_GLO_CFG_TX_DMA_EN |
+ MT_WFDMA0_GLO_CFG_RX_DMA_EN |
+ MT_WFDMA0_GLO_CFG_CSR_DISP_BASE_PTR_CHAIN_EN |
+ MT_WFDMA0_GLO_CFG_OMIT_TX_INFO |
+ MT_WFDMA0_GLO_CFG_OMIT_RX_INFO_PFET2);
+ wmb();
+
+ if (!mt76_poll_msec_tick(dev, MT_WFDMA0_GLO_CFG,
+ MT_WFDMA0_GLO_CFG_TX_DMA_BUSY |
+ MT_WFDMA0_GLO_CFG_RX_DMA_BUSY, 0, 100, 1))
+ return -ETIMEDOUT;
+
+ /* Reset DMA descriptor pointers */
+ mt76_wr(dev, MT_WFDMA0_RST_DTX_PTR, ~0);
+ mt76_wr(dev, MT_WFDMA0_RST_DRX_PTR, ~0);
+ wmb();
+ msleep(10);
+
+ /* init tx queue - ring 0 */
+ ret = mt76_connac_init_tx_queues(dev->phy.mt76, MT7925_TXQ_BAND0,
+ MT7925_TX_RING_SIZE,
+ MT_TX_RING_BASE, NULL, 0);
+ if (ret)
+ return ret;
+
+ mt76_wr(dev, MT_WFDMA0_TX_RING0_EXT_CTRL, 0x4);
+
+ /* command to WM - ring 15 */
+ ret = mt76_init_mcu_queue(&dev->mt76, MT_MCUQ_WM,
+ MT7925_TXQ_MCU_WM,
+ MT7925_TX_MCU_RING_SIZE, MT_TX_RING_BASE);
+ if (ret)
+ return ret;
+
+ /* firmware download - ring 16 */
+ ret = mt76_init_mcu_queue(&dev->mt76, MT_MCUQ_FWDL,
+ MT7925_TXQ_FWDL,
+ MT7925_TX_FWDL_RING_SIZE, MT_TX_RING_BASE);
+ if (ret)
+ return ret;
+
+ /* rx MCU events - ring 6 (MT7925 uses ring 0) */
+ ret = mt76_queue_alloc(dev, &dev->mt76.q_rx[MT_RXQ_MCU],
+ MT7927_RXQ_MCU_WM, MT7925_RX_MCU_RING_SIZE,
+ MT_RX_BUF_SIZE, MT_RX_EVENT_RING_BASE);
+ if (ret)
+ return ret;
+
+ /* rx data - ring 4 (MT7925 uses ring 2) */
+ ret = mt76_queue_alloc(dev, &dev->mt76.q_rx[MT_RXQ_MAIN],
+ MT7927_RXQ_BAND0, MT7925_RX_RING_SIZE,
+ MT_RX_BUF_SIZE, MT_RX_DATA_RING_BASE);
+ if (ret)
+ return ret;
+
+ /* rx auxiliary - ring 7: management frames */
+ ret = mt76_queue_alloc(dev, &dev->mt76.q_rx[MT_RXQ_MCU_WA],
+ MT7927_RXQ_DATA2, MT7925_RX_MCU_RING_SIZE,
+ MT_RX_BUF_SIZE, MT_RX_DATA_RING_BASE);
+ if (ret)
+ return ret;
+
+ ret = mt76_init_queues(dev, mt792x_poll_rx);
+ if (ret < 0)
+ return ret;
+
+ netif_napi_add_tx(dev->mt76.tx_napi_dev, &dev->mt76.tx_napi,
+ mt792x_poll_tx);
+ napi_enable(&dev->mt76.tx_napi);
+
+ /* MT7927-specific GLO_CFG bits before DMA enable */
+ mt76_set(dev, MT_WFDMA0_GLO_CFG, BIT(26)); /* ADDR_EXT_EN */
+ mt76_clear(dev, MT_WFDMA0_GLO_CFG, BIT(20)); /* CSR_LBK_RX_Q_SEL_EN */
+ mt76_set(dev, MT_WFDMA0_GLO_CFG_EXT1, BIT(28));
+ mt76_set(dev, MT_WFDMA0_GLO_CFG,
+ MT_WFDMA0_GLO_CFG_FW_DWLD_BYPASS_DMASHDL);
+
+ ret = mt792x_dma_enable(dev);
+ if (ret)
+ return ret;
+
+ /* Enable interrupts synchronously */
+ mt76_wr(dev, MT_WFDMA0_HOST_INT_ENA, dev->mt76.mmio.irqmask);
+
+ return 0;
+}
+
+static const struct mt792x_irq_map mt7927_irq_map = {
+ .host_irq_enable = MT_WFDMA0_HOST_INT_ENA,
+ .tx = {
+ .all_complete_mask = MT_INT_TX_DONE_ALL,
+ .mcu_complete_mask = MT_INT_TX_DONE_MCU,
+ },
+ .rx = {
+ .data_complete_mask = HOST_RX_DONE_INT_ENA4,
+ .wm_complete_mask = HOST_RX_DONE_INT_ENA6,
+ .wm2_complete_mask = HOST_RX_DONE_INT_ENA7,
+ },
+};
+
static int mt7925_pci_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
@@ -417,7 +538,10 @@ static int mt7925_pci_probe(struct pci_dev *pdev,
dev = container_of(mdev, struct mt792x_dev, mt76);
dev->fw_features = features;
dev->hif_ops = &mt7925_pcie_ops;
- dev->irq_map = &irq_map;
+ if (is_mt7927_hw)
+ dev->irq_map = &mt7927_irq_map;
+ else
+ dev->irq_map = &irq_map;
mt76_mmio_init(&dev->mt76, pcim_iomap_table(pdev)[0]);
tasklet_init(&mdev->irq_tasklet, mt792x_irq_tasklet, (unsigned long)dev);
@@ -489,7 +613,10 @@ static int mt7925_pci_probe(struct pci_dev *pdev,
if (ret)
goto err_free_dev;
- ret = mt7925_dma_init(dev);
+ if (is_mt7927_hw)
+ ret = mt7927_dma_init(dev);
+ else
+ ret = mt7925_dma_init(dev);
if (ret)
goto err_free_irq;
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x_dma.c b/drivers/net/wireless/mediatek/mt76/mt792x_dma.c
index 1ddec7788b66..3177c6cc6eb5 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x_dma.c
+++ b/drivers/net/wireless/mediatek/mt76/mt792x_dma.c
@@ -90,7 +90,23 @@ EXPORT_SYMBOL_GPL(mt792x_rx_poll_complete);
#define PREFETCH(base, depth) ((base) << 16 | (depth))
static void mt792x_dma_prefetch(struct mt792x_dev *dev)
{
- if (is_mt7925(&dev->mt76)) {
+ if (is_mt7927(&dev->mt76)) {
+ /* Trigger prefetch controller reset before reprogramming */
+ mt76_wr(dev, MT_WFDMA_PREFETCH_CTRL,
+ mt76_rr(dev, MT_WFDMA_PREFETCH_CTRL));
+ /* MT7927 uses packed prefetch registers */
+ mt76_wr(dev, MT_WFDMA_PREFETCH_CFG0, 0x660077);
+ mt76_wr(dev, MT_WFDMA_PREFETCH_CFG1, 0x1100);
+ mt76_wr(dev, MT_WFDMA_PREFETCH_CFG2, 0x30004f);
+ mt76_wr(dev, MT_WFDMA_PREFETCH_CFG3, 0x542200);
+ /* per-ring EXT_CTRL */
+ mt76_wr(dev, MT_WFDMA0_RX_RING4_EXT_CTRL, PREFETCH(0x0000, 0x8));
+ mt76_wr(dev, MT_WFDMA0_RX_RING6_EXT_CTRL, PREFETCH(0x0080, 0x8));
+ mt76_wr(dev, MT_WFDMA0_RX_RING7_EXT_CTRL, PREFETCH(0x0100, 0x4));
+ mt76_wr(dev, MT_WFDMA0_TX_RING16_EXT_CTRL, PREFETCH(0x0140, 0x4));
+ mt76_wr(dev, MT_WFDMA0_TX_RING15_EXT_CTRL, PREFETCH(0x0180, 0x10));
+ mt76_wr(dev, MT_WFDMA0_TX_RING0_EXT_CTRL, PREFETCH(0x0280, 0x4));
+ } else if (is_mt7925(&dev->mt76)) {
/* rx ring */
mt76_wr(dev, MT_WFDMA0_RX_RING0_EXT_CTRL, PREFETCH(0x0000, 0x4));
mt76_wr(dev, MT_WFDMA0_RX_RING1_EXT_CTRL, PREFETCH(0x0040, 0x4));
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x_regs.h b/drivers/net/wireless/mediatek/mt76/mt792x_regs.h
index 0f75dca0a96c..5497cfaab8d7 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x_regs.h
+++ b/drivers/net/wireless/mediatek/mt76/mt792x_regs.h
@@ -363,6 +363,16 @@
#define MT_WFDMA_EXT_CSR_HIF_MISC MT_WFDMA_EXT_CSR(0x44)
#define MT_WFDMA_EXT_CSR_HIF_MISC_BUSY BIT(0)
+/* MT7927 packed prefetch registers */
+#define MT_WFDMA_PREFETCH_CTRL MT_WFDMA_EXT_CSR(0x30)
+#define MT_WFDMA_PREFETCH_CFG0 MT_WFDMA_EXT_CSR(0xf0)
+#define MT_WFDMA_PREFETCH_CFG1 MT_WFDMA_EXT_CSR(0xf4)
+#define MT_WFDMA_PREFETCH_CFG2 MT_WFDMA_EXT_CSR(0xf8)
+#define MT_WFDMA_PREFETCH_CFG3 MT_WFDMA_EXT_CSR(0xfc)
+
+/* MT7927 GLO_CFG extended register */
+#define MT_WFDMA0_GLO_CFG_EXT1 MT_WFDMA0(0x2b4)
+
#define MT_SWDEF_BASE 0x41f200
#define MT_SWDEF(ofs) (MT_SWDEF_BASE + (ofs))
#define MT_SWDEF_MODE MT_SWDEF(0x3c)
--
2.53.0
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