On Wed, Feb 8, 2017 at 5:35 PM, Yung-Ching LIN yungching0725@gmail.com wrote:
On Wed, Feb 8, 2017 at 10:47 AM, Joe Hershberger joe.hershberger@gmail.com wrote:
On Wed, Feb 8, 2017 at 12:26 AM, Sekhar Nori nsekhar@ti.com wrote:
On Wednesday 08 February 2017 12:36 AM, Yung-Ching LIN wrote:
On Tue, Feb 7, 2017 at 12:50 AM, Sekhar Nori nsekhar@ti.com wrote:
On Monday 06 February 2017 11:06 PM, Ken.Lin wrote:
>> The register setting would turn out to be 0x3D47 on our project boards and > our signal measurement results show the patch (v2 version, > https://patchwork.ozlabs.org/patch/723461/)) could fix the voltage peak issue. >> The proposed solution is to follow the implementation in previous commits, > which include the reserved bits settings in SerDes Test and System Mode Control > register.
> So what does the register setting turn out to be with my patch below ? > > What are the "previous commits" you refer to ?
Thanks for the references to the commits. You left out answering my question about what register settings you see with my patch.
I have included another patch now with some debug enabled. Can you apply this patch to latest u-boot master, run on your board and send me the log ? Here is what I see on AM335x EVM-SK:
U-Boot 2017.03-rc1-00058-g1216f9a0851f (Feb 07 2017 - 13:55:38 +0530)
CPU : AM335X-GP rev 1.0 Model: TI AM335x EVM-SK DRAM: 256 MiB NAND: 0 MiB MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1 reading uboot.env ERROR: No USB device found
at ../drivers/usb/gadget/ether.c:2709/usb_ether_init() Net: ar8031_config: value read back 0x2c47, written: 0x2d47 eth0: ethernet@4a100000 Hit any key to stop autoboot: 0
Thanks, Sekhar
---8<--- diff --git a/drivers/net/phy/atheros.c b/drivers/net/phy/atheros.c index b34cdd3d87dc..5c0a36676ce9 100644 --- a/drivers/net/phy/atheros.c +++ b/drivers/net/phy/atheros.c @@ -28,12 +28,18 @@ static int ar8021_config(struct phy_device *phydev)
static int ar8031_config(struct phy_device *phydev) {
int regval;if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID || phydev->interface == PHY_INTERFACE_MODE_RGMII_ID) { phy_write(phydev, MDIO_DEVAD_NONE, AR803x_PHY_DEBUG_ADDR_REG, AR803x_DEBUG_REG_5);regval = phy_read(phydev, MDIO_DEVAD_NONE,AR803x_PHY_DEBUG_DATA_REG);printf("%s: value read back 0x%x, written: 0x%x\n",__func__, regval, regval | AR803x_RGMII_TX_CLK_DLY); phy_write(phydev, MDIO_DEVAD_NONE, AR803x_PHY_DEBUG_DATA_REG,
AR803x_RGMII_TX_CLK_DLY);
regval | AR803x_RGMII_TX_CLK_DLY); } if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID ||
Your read-modify-write patch makes sense to me at some point. I added some debug messages in the u-boot source. ar8031_config gets called after the board specific mx6_rgmii_rework callback In our board test case, the phydev interface uses PHY_INTERFACE_MODE_RGMII, so it won't hit the condition and run the code statements you implemented.
U-Boot 2016.11-g922cf19526-dirty (Mar 03 2017 - 07:13:39 +0800)
CPU: Freescale i.MX6D rev1.5 at 792 MHz Reset cause: POR BOARD: General Electric B850v3 I2C: ready DRAM: 2 GiB MMC: FSL_SDHC: 0, FSL_SDHC: 1, FSL_SDHC: 2 SF: Detected N25Q32 with page size 256 Bytes, erase size 4 KiB, total 4 MiB *** Warning - bad CRC, using default environment
In: serial Out: serial Err: serial Net: eth_init: fec_probe(bd, -1, 4) @ 02188000 fec_mii_setspeed: mii_speed 0000001a fec_mdio_read: phy: 04 reg:02 val:0x4d fec_mdio_read: phy: 04 reg:03 val:0xd074 fec_mii_setspeed: mii_speed 0000001a fec_mdio_write: phy: 04 reg:00 val:0x8000 fec_mdio_read: phy: 04 reg:00 val:0x0 ++mx6_rgmii_rework fec_mdio_write: phy: 04 reg:0d val:0x7 fec_mdio_write: phy: 04 reg:0e val:0x8016 fec_mdio_write: phy: 04 reg:0d val:0x4007 fec_mdio_write: phy: 04 reg:0e val:0x18 fec_mdio_write: phy: 04 reg:1d val:0x5 fec_mdio_write: phy: 04 reg:1e val:0x3d47 --mx6_rgmii_rework ++ar8031_config fec_mdio_read: phy: 04 reg:04 val:0x1de1 fec_mdio_write: phy: 04 reg:04 val:0x11e1 fec_mdio_read: phy: 04 reg:01 val:0x7949 fec_mdio_read: phy: 04 reg:09 val:0x200 fec_mdio_write: phy: 04 reg:09 val:0x300 fec_mdio_read: phy: 04 reg:00 val:0x0 fec_mdio_write: phy: 04 reg:00 val:0x1200 fec_mdio_read: phy: 04 reg:00 val:0x1000 fec_mdio_write: phy: 04 reg:00 val:0x1200 --ar8031_config FEC [PRIME] Error: FEC address not set.
Hmm, so in effect you are forced to use the magic value of 0x3c47 as the reset default when actually it is 0x100 on your board. And there is no backing public documentation on why the reset default should be 0x3c47. And whether it will work for all boards that use this PHY.
Well that's quite unfortunate.
Thats pretty unmaintainable in my opinion. If this value does not work for the next person that comes along, we will be in trouble again.
I guess the best thing that can be done at this point is to use this magic reset default value in a board specific way. By specifying it using device-tree, perhaps. I would wait for some feedback from Joe Hershberger though.
I think we can wait until someone else says they have a problem with this value before making it a board option.
Sorry for causing the confusion. Our board specific requirement(issue) for setting proper register value could be done in the board file. I resubmitted the patch at https://lists.denx.de/pipermail/u-boot/2017-February/281894.html
BTW, do you have the same problem in kernel ? Because AFAICS, even drivers/net/phy/at803x.c in kernel does not have any such provision for magic reset default values.
I'm interested to know this too. Is the kernel depending on the bootloader to set this and it just avoids changing it?
Yes, I think so.Here are the code snippets in drivers/net/phy/at803x.c. I found it wouldn't change the bootloader setting when I dumped the value in kernel.
static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg, u16 clear, u16 set) { u16 val; int ret;
ret = at803x_debug_reg_read(phydev, reg); if (ret < 0) return ret; val = ret & 0xffff; val &= ~clear; val |= set; return phy_write(phydev, AT803X_DEBUG_DATA, val);}
static inline int at803x_enable_tx_delay(struct phy_device *phydev) { return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5, 0, AT803X_DEBUG_TX_CLK_DLY_EN); }
Thanks, Sekhar _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot