stmmac: re-work the internal GMAC DMA platf parameters

This patch re-works the internal GMAC DMA parameters
passed from the platform.
In the past, we only passed the pbl but, with new core,
other parameters can be passed and are mandatory on some
platforms.

New parameters are documented in stmmac.txt because this
patch has an impact for many platforms.

Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Vikas Manocha <vikas.manocha@st.com>
Signed-off-by: Deepak Sikri <deepak.sikri@st.com>
Hacked-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

7 files changed, 49 insertions, 12 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
index eec8d34b6c88..b14829f8085d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/common.h
+++ b/drivers/net/ethernet/stmicro/stmmac/common.h
@@ -236,7 +236,8 @@ struct stmmac_desc_ops {
 
 struct stmmac_dma_ops {
 	/* DMA core initialization */
-	int (*init) (void __iomem *ioaddr, int pbl, u32 dma_tx, u32 dma_rx);
+	int (*init) (void __iomem *ioaddr, int pbl, int fb, int burst_len,
+			u32 dma_tx, u32 dma_rx);
 	/* Dump DMA registers */
 	void (*dump_regs) (void __iomem *ioaddr);
 	/* Set tx/rx threshold in the csr6 register
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h b/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
index cfcef0ea0fa5..54339a78e358 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000.h
@@ -142,7 +142,7 @@ enum rx_tx_priority_ratio {
 #define DMA_BUS_MODE_RPBL_MASK	0x003e0000	/* Rx-Programmable Burst Len */
 #define DMA_BUS_MODE_RPBL_SHIFT	17
 #define DMA_BUS_MODE_USP	0x00800000
-#define DMA_BUS_MODE_4PBL	0x01000000
+#define DMA_BUS_MODE_PBL	0x01000000
 #define DMA_BUS_MODE_AAL	0x02000000
 
 /* DMA CRS Control and Status Register Mapping */
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c
index 4d5402a1d262..3675c5731565 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c
@@ -30,8 +30,8 @@
 #include "dwmac1000.h"
 #include "dwmac_dma.h"
 
-static int dwmac1000_dma_init(void __iomem *ioaddr, int pbl, u32 dma_tx,
-			      u32 dma_rx)
+static int dwmac1000_dma_init(void __iomem *ioaddr, int pbl, int fb,
+			      int burst_len, u32 dma_tx, u32 dma_rx)
 {
 	u32 value = readl(ioaddr + DMA_BUS_MODE);
 	int limit;
@@ -48,15 +48,47 @@ static int dwmac1000_dma_init(void __iomem *ioaddr, int pbl, u32 dma_tx,
 	if (limit < 0)
 		return -EBUSY;
 
-	value = /* DMA_BUS_MODE_FB | */ DMA_BUS_MODE_4PBL |
-	    ((pbl << DMA_BUS_MODE_PBL_SHIFT) |
-	     (pbl << DMA_BUS_MODE_RPBL_SHIFT));
+	/*
+	 * Set the DMA PBL (Programmable Burst Length) mode
+	 * Before stmmac core 3.50 this mode bit was 4xPBL, and
+	 * post 3.5 mode bit acts as 8*PBL.
+	 * For core rev < 3.5, when the core is set for 4xPBL mode, the
+	 * DMA transfers the data in 4, 8, 16, 32, 64 & 128 beats
+	 * depending on pbl value.
+	 * For core rev > 3.5, when the core is set for 8xPBL mode, the
+	 * DMA transfers the data in 8, 16, 32, 64, 128 & 256 beats
+	 * depending on pbl value.
+	 */
+	value = DMA_BUS_MODE_PBL | ((pbl << DMA_BUS_MODE_PBL_SHIFT) |
+		(pbl << DMA_BUS_MODE_RPBL_SHIFT));
+
+	/* Set the Fixed burst mode */
+	if (fb)
+		value |= DMA_BUS_MODE_FB;
 
 #ifdef CONFIG_STMMAC_DA
 	value |= DMA_BUS_MODE_DA;	/* Rx has priority over tx */
 #endif
 	writel(value, ioaddr + DMA_BUS_MODE);
 
+	/* In case of GMAC AXI configuration, program the DMA_AXI_BUS_MODE
+	 * for supported bursts.
+	 *
+	 * Note: This is applicable only for revision GMACv3.61a. For
+	 * older version this register is reserved and shall have no
+	 * effect.
+	 *
+	 * Note:
+	 *  For Fixed Burst Mode: if we directly write 0xFF to this
+	 *  register using the configurations pass from platform code,
+	 *  this would ensure that all bursts supported by core are set
+	 *  and those which are not supported would remain ineffective.
+	 *
+	 *  For Non Fixed Burst Mode: provide the maximum value of the
+	 *  burst length. Any burst equal or below the provided burst
+	 *  length would be allowed to perform. */
+	writel(burst_len, ioaddr + DMA_AXI_BUS_MODE);
+
 	/* Mask interrupts by writing to CSR7 */
 	writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_INTR_ENA);
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c
index bc17fd08b55d..92ed2e07609e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c
@@ -32,8 +32,8 @@
 #include "dwmac100.h"
 #include "dwmac_dma.h"
 
-static int dwmac100_dma_init(void __iomem *ioaddr, int pbl, u32 dma_tx,
-			     u32 dma_rx)
+static int dwmac100_dma_init(void __iomem *ioaddr, int pbl, int fb,
+			     int burst_len, u32 dma_tx, u32 dma_rx)
 {
 	u32 value = readl(ioaddr + DMA_BUS_MODE);
 	int limit;
@@ -52,7 +52,7 @@ static int dwmac100_dma_init(void __iomem *ioaddr, int pbl, u32 dma_tx,
 
 	/* Enable Application Access by writing to DMA CSR0 */
 	writel(DMA_BUS_MODE_DEFAULT | (pbl << DMA_BUS_MODE_PBL_SHIFT),
-	       ioaddr + DMA_BUS_MODE);
+			ioaddr + DMA_BUS_MODE);
 
 	/* Mask interrupts by writing to CSR7 */
 	writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_INTR_ENA);
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac_dma.h b/drivers/net/ethernet/stmicro/stmmac/dwmac_dma.h
index 437edacd602e..6e0360f9cfde 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac_dma.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac_dma.h
@@ -32,6 +32,7 @@
 #define DMA_CONTROL		0x00001018	/* Ctrl (Operational Mode) */
 #define DMA_INTR_ENA		0x0000101c	/* Interrupt Enable */
 #define DMA_MISSED_FRAME_CTR	0x00001020	/* Missed Frame Counter */
+#define DMA_AXI_BUS_MODE       0x00001028      /* AXI Bus Mode */
 #define DMA_CUR_TX_BUF_ADDR	0x00001050	/* Current Host Tx Buffer */
 #define DMA_CUR_RX_BUF_ADDR	0x00001054	/* Current Host Rx Buffer */
 #define DMA_HW_FEATURE		0x00001058	/* HW Feature Register */
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 84f6b348ec70..933f63c4b2f3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -944,7 +944,9 @@ static int stmmac_open(struct net_device *dev)
 	init_dma_desc_rings(dev);
 
 	/* DMA initialization and SW reset */
-	ret = priv->hw->dma->init(priv->ioaddr, priv->plat->pbl,
+	ret = priv->hw->dma->init(priv->ioaddr, priv->plat->dma_cfg->pbl,
+				  priv->plat->dma_cfg->fixed_burst,
+				  priv->plat->dma_cfg->burst_len,
 				  priv->dma_tx_phy, priv->dma_rx_phy);
 	if (ret < 0) {
 		pr_err("%s: DMA initialization failed\n", __func__);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
index da66ed7c3c5d..65e0f98520d6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
@@ -35,7 +35,8 @@ static void stmmac_default_data(void)
 	plat_dat.bus_id = 1;
 	plat_dat.phy_addr = 0;
 	plat_dat.interface = PHY_INTERFACE_MODE_GMII;
-	plat_dat.pbl = 32;
+	plat_dat.dma_cfg->pbl = 32;
+	plat_dat.dma_cfg->burst_len = DMA_AXI_BLEN_256;
 	plat_dat.clk_csr = 2;	/* clk_csr_i = 20-35MHz & MDC = clk_csr_i/16 */
 	plat_dat.has_gmac = 1;
 	plat_dat.force_sf_dma_mode = 1;