diff options
Diffstat (limited to 'drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c')
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c | 46 |
1 files changed, 41 insertions, 5 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c index 4d5402a1d262..033500090f55 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 mb, int burst_len, u32 dma_tx, u32 dma_rx) { u32 value = readl(ioaddr + DMA_BUS_MODE); int limit; @@ -48,15 +48,51 @@ 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; + + /* Mixed Burst has no effect when fb is set */ + if (mb) + value |= DMA_BUS_MODE_MB; #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); |