Re: [PATCH v2] net: macb: Clean 64b dma addresses if they are not detected

From: Nicolas Ferre
Date: Tue Sep 25 2018 - 03:00:41 EST

On 25/09/2018 at 08:32, Michal Simek wrote:
Clear ADDR64 dma bit in DMACFG register in case that HW_DMA_CAP_64B is
not detected on 64bit system.
The issue was observed when bootloader(u-boot) does not check macb
feature at DCFG6 register (DAW64_OFFSET) and enabling 64bit dma support
by default. Then macb driver is reading DMACFG register back and only
adding 64bit dma configuration but not cleaning it out.

Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>

Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>

Thanks Michal. Best regards,


Changes in v2:
- Clean reg at the first place - Edgar
- Update commit message

drivers/net/ethernet/cadence/macb_main.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 16e4ef7d7185..ed8a5c53467e 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -2160,6 +2160,7 @@ static void macb_configure_dma(struct macb *bp)
dmacfg &= ~GEM_BIT(TXCOEN);
+ dmacfg &= ~GEM_BIT(ADDR64);
if (bp->hw_dma_cap & HW_DMA_CAP_64B)
dmacfg |= GEM_BIT(ADDR64);

Nicolas Ferre