[U-Boot] [PATCH 6/6] net: macb: apply sane DMA configuration

Ramon Fried
2019-07-16T19:03:05Z

DMA configuration was heavily dependent on the HW
defaults, add function to properly set the required
fields, including the new dma_burst_length.

Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
---
v2: nothing.
drivers/net/macb.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)

diff --git a/drivers/net/macb.c b/drivers/net/macb.c
index dc6aa6deda..035109dc43 100644
--- a/drivers/net/macb.c
+++ b/drivers/net/macb.c
@@ -47,6 +47,7 @@ DECLARE_GLOBAL_DATA_PTR;

#define MACB_RX_BUFFER_SIZE 4096
#define MACB_RX_RING_SIZE (MACB_RX_BUFFER_SIZE / 128)
+#define RX_BUFFER_MULTIPLE 64
#define MACB_TX_RING_SIZE 16
#define MACB_TX_TIMEOUT 1000
#define MACB_AUTONEG_TIMEOUT 5000000
@@ -697,6 +698,31 @@ static int gmac_init_multi_queues(struct macb_device *macb)
return 0;
}

+static void gmac_configure_dma(struct macb_device *macb)
+{
+ u32 buffer_size;
+ u32 dmacfg;
+
+ buffer_size = 128 / RX_BUFFER_MULTIPLE;
+ dmacfg = gem_readl(macb, DMACFG) & ~GEM_BF(RXBS, -1L);
+ dmacfg |= GEM_BF(RXBS, buffer_size);
+
+ if (macb->dma_burst_length)
+ dmacfg = GEM_BFINS(FBLDO, macb->dma_burst_length, dmacfg);
+
+ dmacfg |= GEM_BIT(TXPBMS) | GEM_BF(RXBMS, -1L);
+ dmacfg &= ~GEM_BIT(ENDIA_PKT);
+
+#ifdef CONFIG_SYS_LITTLE_ENDIAN
+ dmacfg &= ~GEM_BIT(ENDIA_DESC);
+#else
+ dmacfg |= GEM_BIT(ENDIA_DESC); /* CPU in big endian */
+#endif
+
+ dmacfg &= ~GEM_BIT(ADDR64);
+ gem_writel(macb, DMACFG, dmacfg);
+}
+
#ifdef CONFIG_DM_ETH
static int _macb_init(struct udevice *dev, const char *name)
#else
@@ -750,6 +776,8 @@ static int _macb_init(struct macb_device *macb, const char *name)
macb_writel(macb, TBQP, macb->tx_ring_dma);

if (macb_is_gem(macb)) {
+ /* Initialize DMA properties */
+ gmac_configure_dma(macb);
/* Check the multi queue and initialize the queue for tx */
gmac_init_multi_queues(macb);

--
2.22.0