[U-Boot] [PATCH] drivers/net/designware - respect "bus mode" register contents on SW reset

[Alexey Brodkin]

"bus mode" register contains lots of fields and some of them don't
expect to be written with 0 (zero). So since we're only interested in
resetting MAC (which is done with setting the least significant bit of
this register with "0") I believe it's better to modify only 1 bit of
the register.

Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
---
 drivers/net/designware.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/designware.c b/drivers/net/designware.c
index 46f6601..f11cb0b 100644
--- a/drivers/net/designware.c
+++ b/drivers/net/designware.c
@@ -112,7 +112,7 @@ static int mac_reset(struct eth_device *dev)
 	ulong start;
 	int timeout = CONFIG_MACRESET_TIMEOUT;
 
-	writel(DMAMAC_SRST, &dma_p->busmode);
+	writel(readl(&dma_p->busmode) | DMAMAC_SRST, &dma_p->busmode);
 
 	if (priv->interface != PHY_INTERFACE_MODE_RGMII)
 		writel(MII_PORTSELECT, &mac_p->conf);
-- 
1.8.1.2