From: Dylan Hung dylan_hung@aspeedtech.com
[ Upstream commit 137d23cea1c044b2d4853ac71bc68126b25fdbb2 ]
The new HW arbitration feature on Aspeed ast2600 will cause MAC TX to hang when handling scatter-gather DMA. Disable the problematic feature by setting MAC register 0x58 bit28 and bit27.
Fixes: 39bfab8844a0 ("net: ftgmac100: Add support for DT phy-handle property") Signed-off-by: Dylan Hung dylan_hung@aspeedtech.com Reviewed-by: Joel Stanley joel@jms.id.au Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/faraday/ftgmac100.c | 5 +++++ drivers/net/ethernet/faraday/ftgmac100.h | 8 ++++++++ 2 files changed, 13 insertions(+)
--- a/drivers/net/ethernet/faraday/ftgmac100.c +++ b/drivers/net/ethernet/faraday/ftgmac100.c @@ -1817,6 +1817,11 @@ static int ftgmac100_probe(struct platfo priv->rxdes0_edorr_mask = BIT(30); priv->txdes0_edotr_mask = BIT(30); priv->is_aspeed = true; + /* Disable ast2600 problematic HW arbitration */ + if (of_device_is_compatible(np, "aspeed,ast2600-mac")) { + iowrite32(FTGMAC100_TM_DEFAULT, + priv->base + FTGMAC100_OFFSET_TM); + } } else { priv->rxdes0_edorr_mask = BIT(15); priv->txdes0_edotr_mask = BIT(15); --- a/drivers/net/ethernet/faraday/ftgmac100.h +++ b/drivers/net/ethernet/faraday/ftgmac100.h @@ -170,6 +170,14 @@ #define FTGMAC100_MACCR_SW_RST (1 << 31)
/* + * test mode control register + */ +#define FTGMAC100_TM_RQ_TX_VALID_DIS (1 << 28) +#define FTGMAC100_TM_RQ_RR_IDLE_PREV (1 << 27) +#define FTGMAC100_TM_DEFAULT \ + (FTGMAC100_TM_RQ_TX_VALID_DIS | FTGMAC100_TM_RQ_RR_IDLE_PREV) + +/* * PHY control register */ #define FTGMAC100_PHYCR_MDC_CYCTHR_MASK 0x3f