stmmac: share reset function between dwmac100 and dwmac1000

This patch is to share the same reset procedure between dwmac100 and
dwmac1000 chips.
This will also help on enhancing the driver and support new chips.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/common.h

@@ -376,7 +376,8 @@ extern const struct stmmac_desc_ops ndesc_ops;
 /* Specific DMA helpers */
 struct stmmac_dma_ops {
 	/* DMA core initialization */
-	int (*init) (void __iomem *ioaddr, int pbl, int fb, int mb,
+	int (*reset)(void __iomem *ioaddr);
+	void (*init)(void __iomem *ioaddr, int pbl, int fb, int mb,
 		     int burst_len, u32 dma_tx, u32 dma_rx, int atds);
 	/* Dump DMA registers */
 	void (*dump_regs) (void __iomem *ioaddr);

drivers/net/ethernet/stmicro/stmmac/dwmac100.h

@@ -95,7 +95,6 @@
 #define DMA_BUS_MODE_DSL_MASK	0x0000007c	/* Descriptor Skip Length */
 #define DMA_BUS_MODE_DSL_SHIFT	2	/*   (in DWORDS)      */
 #define DMA_BUS_MODE_BAR_BUS	0x00000002	/* Bar-Bus Arbitration */
-#define DMA_BUS_MODE_SFT_RESET	0x00000001	/* Software Reset */
 #define DMA_BUS_MODE_DEFAULT	0x00000000
 
 /* DMA Control register defines */

drivers/net/ethernet/stmicro/stmmac/dwmac1000.h

@@ -221,7 +221,6 @@ enum inter_frame_gap {
 
 /*--- DMA BLOCK defines ---*/
 /* DMA Bus Mode register defines */
-#define DMA_BUS_MODE_SFT_RESET	0x00000001	/* Software Reset */
 #define DMA_BUS_MODE_DA		0x00000002	/* Arbitration scheme */
 #define DMA_BUS_MODE_DSL_MASK	0x0000007c	/* Descriptor Skip Length */
 #define DMA_BUS_MODE_DSL_SHIFT	2		/*   (in DWORDS)      */

drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c

@@ -30,23 +30,10 @@
 #include "dwmac1000.h"
 #include "dwmac_dma.h"
 
-static int dwmac1000_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
+static void dwmac1000_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
 			       int burst_len, u32 dma_tx, u32 dma_rx, int atds)
 {
-	u32 value = readl(ioaddr + DMA_BUS_MODE);
-	int limit;
-
-	/* DMA SW reset */
-	value |= DMA_BUS_MODE_SFT_RESET;
-	writel(value, ioaddr + DMA_BUS_MODE);
-	limit = 10;
-	while (limit--) {
-		if (!(readl(ioaddr + DMA_BUS_MODE) & DMA_BUS_MODE_SFT_RESET))
-			break;
-		mdelay(10);
-	}
-	if (limit < 0)
-		return -EBUSY;
+	u32 value;
 
 	/*
 	 * Set the DMA PBL (Programmable Burst Length) mode
@@ -102,8 +89,6 @@ static int dwmac1000_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
 	 */
 	writel(dma_tx, ioaddr + DMA_TX_BASE_ADDR);
 	writel(dma_rx, ioaddr + DMA_RCV_BASE_ADDR);
-
-	return 0;
 }
 
 static u32 dwmac1000_configure_fc(u32 csr6, int rxfifosz)
@@ -205,6 +190,7 @@ static void dwmac1000_rx_watchdog(void __iomem *ioaddr, u32 riwt)
 }
 
 const struct stmmac_dma_ops dwmac1000_dma_ops = {
+	.reset = dwmac_dma_reset,
 	.init = dwmac1000_dma_init,
 	.dump_regs = dwmac1000_dump_dma_regs,
 	.dma_mode = dwmac1000_dma_operation_mode,

drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c

@@ -32,24 +32,9 @@
 #include "dwmac100.h"
 #include "dwmac_dma.h"
 
-static int dwmac100_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
+static void dwmac100_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
 			      int burst_len, u32 dma_tx, u32 dma_rx, int atds)
 {
-	u32 value = readl(ioaddr + DMA_BUS_MODE);
-	int limit;
-
-	/* DMA SW reset */
-	value |= DMA_BUS_MODE_SFT_RESET;
-	writel(value, ioaddr + DMA_BUS_MODE);
-	limit = 10;
-	while (limit--) {
-		if (!(readl(ioaddr + DMA_BUS_MODE) & DMA_BUS_MODE_SFT_RESET))
-			break;
-		mdelay(10);
-	}
-	if (limit < 0)
-		return -EBUSY;
-
 	/* Enable Application Access by writing to DMA CSR0 */
 	writel(DMA_BUS_MODE_DEFAULT | (pbl << DMA_BUS_MODE_PBL_SHIFT),
 	       ioaddr + DMA_BUS_MODE);
@@ -62,8 +47,6 @@ static int dwmac100_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
 	 */
 	writel(dma_tx, ioaddr + DMA_TX_BASE_ADDR);
 	writel(dma_rx, ioaddr + DMA_RCV_BASE_ADDR);
-
-	return 0;
 }
 
 /* Store and Forward capability is not used at all.
@@ -131,6 +114,7 @@ static void dwmac100_dma_diagnostic_fr(void *data, struct stmmac_extra_stats *x,
 }
 
 const struct stmmac_dma_ops dwmac100_dma_ops = {
+	.reset = dwmac_dma_reset,
 	.init = dwmac100_dma_init,
 	.dump_regs = dwmac100_dump_dma_regs,
 	.dma_mode = dwmac100_dma_operation_mode,

drivers/net/ethernet/stmicro/stmmac/dwmac_dma.h

@@ -35,6 +35,10 @@
 #define DMA_CONTROL		0x00001018	/* Ctrl (Operational Mode) */
 #define DMA_INTR_ENA		0x0000101c	/* Interrupt Enable */
 #define DMA_MISSED_FRAME_CTR	0x00001020	/* Missed Frame Counter */
+
+/* SW Reset */
+#define DMA_BUS_MODE_SFT_RESET	0x00000001	/* Software Reset */
+
 /* Rx watchdog register */
 #define DMA_RX_WATCHDOG		0x00001024
 /* AXI Bus Mode */
@@ -112,5 +116,6 @@ void dwmac_dma_stop_tx(void __iomem *ioaddr);
 void dwmac_dma_start_rx(void __iomem *ioaddr);
 void dwmac_dma_stop_rx(void __iomem *ioaddr);
 int dwmac_dma_interrupt(void __iomem *ioaddr, struct stmmac_extra_stats *x);
+int dwmac_dma_reset(void __iomem *ioaddr);
 
 #endif /* __DWMAC_DMA_H__ */

drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c

@@ -26,6 +26,27 @@
 
 #define GMAC_HI_REG_AE		0x80000000
 
+int dwmac_dma_reset(void __iomem *ioaddr)
+{
+	u32 value = readl(ioaddr + DMA_BUS_MODE);
+	int limit;
+
+	/* DMA SW reset */
+	value |= DMA_BUS_MODE_SFT_RESET;
+	writel(value, ioaddr + DMA_BUS_MODE);
+	limit = 10;
+	while (limit--) {
+		if (!(readl(ioaddr + DMA_BUS_MODE) & DMA_BUS_MODE_SFT_RESET))
+			break;
+		mdelay(10);
+	}
+
+	if (limit < 0)
+		return -EBUSY;
+
+	return 0;
+}
+
 /* CSR1 enables the transmit DMA to check for new descriptor */
 void dwmac_enable_dma_transmission(void __iomem *ioaddr)
 {

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -1638,6 +1638,7 @@ static int stmmac_init_dma_engine(struct stmmac_priv *priv)
 	int pbl = DEFAULT_DMA_PBL, fixed_burst = 0, burst_len = 0;
 	int mixed_burst = 0;
 	int atds = 0;
+	int ret = 0;
 
 	if (priv->plat->dma_cfg) {
 		pbl = priv->plat->dma_cfg->pbl;
@@ -1649,9 +1650,16 @@ static int stmmac_init_dma_engine(struct stmmac_priv *priv)
 	if (priv->extend_desc && (priv->mode == STMMAC_RING_MODE))
 		atds = 1;
 
-	return priv->hw->dma->init(priv->ioaddr, pbl, fixed_burst, mixed_burst,
+	ret = priv->hw->dma->reset(priv->ioaddr);
+	if (ret) {
+		dev_err(priv->device, "Failed to reset the dma\n");
+		return ret;
+	}
+
+	priv->hw->dma->init(priv->ioaddr, pbl, fixed_burst, mixed_burst,
 			    burst_len, priv->dma_tx_phy,
 			    priv->dma_rx_phy, atds);
+	return ret;
 }
 
 /**