Hello, I'm porting Linux to an old spear600 based platform, and therefore trying to use the stmmac driver on this SoC. Unfortunately, it doesn't work quite well and I'm wondering if the stmmac driver still properly supports the old version of the IP that is used in this SoC. I'm testing with v4.11-rc1.
First, the logs: Linux version 4.11.0-rc1 (thomas@skate) (gcc version 5.4.0 20160609 (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.4) ) #18 Thu Mar 9 09:18:01 CET 2017 [...] libphy: Fixed MDIO Bus: probed stmmaceth e0800000.ethernet: no reset control found stmmac - user ID: 0x10, Synopsys ID: 0x32 stmmaceth e0800000.ethernet: Ring mode enabled stmmaceth e0800000.ethernet: DMA HW capability register supported stmmaceth e0800000.ethernet: Normal descriptors libphy: stmmac: probed stmmaceth e0800000.ethernet (unnamed net_device) (uninitialized): PHY ID 0007c0c4 at 31 IRQ POLL (stmmac-0:1f) active [...] # ifconfig eth0 192.168.1.89 stmmaceth e0800000.ethernet eth0: device MAC address 00:30:d3:21:22:60 Generic PHY stmmac-0:1f: attached PHY driver [Generic PHY] (mii_bus:phy_addr=stmmac-0:1f, irq=-1) stmmaceth e0800000.ethernet: Failed to reset the dma stmmaceth e0800000.ethernet eth0: stmmac_hw_setup: DMA engine initialization failed stmmaceth e0800000.ethernet eth0: stmmac_open: Hw setup failed ifconfig: SIOCSIFFLAGS: Device or resource busy So the reason why it fails to reset the DMA is because dwmac_dma_reset() sets bit DMA_BUS_MODE_SFT_RESET in register DMA_BUS_MODE and waits for this bit to clear, but that never happens. The reason why I'm not sure if this IP is still supported is because dwmac1000_get_hw_feature() reads the DMA_HW_FEATURE register (offset 0x00001058), and my spear600 datasheet doesn't mention this register at all. It is worth mentioning that: - Ethernet is working fine under U-Boot (it's an old 2010.03 U-Boot version, with a good number of patches), so I'm sure the HW is working. - Setting bit 1 in the DMA_BUS_MODE register from U-Boot also leaves this bit set forever, it apparently never clears (unless my tests were wrong, which is very possible). In terms of Device Tree, I'm simply using spear600.dtsi, and enabling the gmac node, nothing else. Has the stmmac driver been recently used/tested on spear600 ? Thanks, Thomas Petazzoni -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com
