From a79de0808a8dc738ec2076ad47d431c64452111e Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Mon, 6 Mar 2023 15:53:46 +0100 Subject: [PATCH] net: dwc_eth_qos: Set DMA_MODE SWR bit to reset the MAC The driver currently only waits for DMA_MODE SWR bit to clear itself. This is insufficient e.g. on i.MX8M Plus, where the MAC must be reset before IOMUX GPR[1] content is latched into the MAC and used. Without the proper reset, the i.MX8M Plus MAC variant does not take the value in IOMUX GPR[1] into account, which makes it impossible e.g. to switch interface mode from RGMII to any other. Since proper reset is desired in general to put the block into defined state, always assert the DMA_MODE SWR bit before waiting for the bit to clear itself. Reviewed-by: Ramon Fried Signed-off-by: Marek Vasut --- drivers/net/dwc_eth_qos.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/dwc_eth_qos.c b/drivers/net/dwc_eth_qos.c index 9a5575e..ec58697 100644 --- a/drivers/net/dwc_eth_qos.c +++ b/drivers/net/dwc_eth_qos.c @@ -761,6 +761,12 @@ static int eqos_start(struct udevice *dev) eqos->reg_access_ok = true; + /* + * Assert the SWR first, the actually reset the MAC and to latch in + * e.g. i.MX8M Plus GPR[1] content, which selects interface mode. + */ + setbits_le32(&eqos->dma_regs->mode, EQOS_DMA_MODE_SWR); + ret = wait_for_bit_le32(&eqos->dma_regs->mode, EQOS_DMA_MODE_SWR, false, eqos->config->swr_wait, false); -- 2.7.4