On 26.01.2022 09:30, Michal Simek wrote:
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> On 1/25/22 18:05, Robert Hancock wrote:
>> The GEM controllers on ZynqMP were missing some initialization steps which
>> are required in some cases when using SGMII mode, which uses the PS-GTR
>> transceivers managed by the phy-zynqmp driver.
>>
>> The GEM core appears to need a hardware-level reset in order to work
>> properly in SGMII mode in cases where the GT reference clock was not
>> present at initial power-on. This can be done using a reset mapped to
>> the zynqmp-reset driver in the device tree.
>>
>> Also, when in SGMII mode, the GEM driver needs to ensure the PHY is
>> initialized and powered on when it is initializing.
>>
>> Signed-off-by: Robert Hancock <robert.hancock@xxxxxxxxxx>
>> ---
>> drivers/net/ethernet/cadence/macb_main.c | 48 +++++++++++++++++++++++-
>> 1 file changed, 47 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ethernet/cadence/macb_main.c
>> b/drivers/net/ethernet/cadence/macb_main.c
>> index a363da928e8b..80882908a68f 100644
>> --- a/drivers/net/ethernet/cadence/macb_main.c
>> +++ b/drivers/net/ethernet/cadence/macb_main.c
>> @@ -34,7 +34,9 @@
>> #include <linux/udp.h>
>> #include <linux/tcp.h>
>> #include <linux/iopoll.h>
>> +#include <linux/phy/phy.h>
>> #include <linux/pm_runtime.h>
>> +#include <linux/reset.h>
>> #include "macb.h"
>>
>> /* This structure is only used for MACB on SiFive FU540 devices */
>> @@ -4455,6 +4457,50 @@ static int fu540_c000_init(struct platform_device
>> *pdev)
>> return macb_init(pdev);
>> }
>>
>> +static int zynqmp_init(struct platform_device *pdev)
>> +{
>> + struct net_device *dev = platform_get_drvdata(pdev);
>> + struct macb *bp = netdev_priv(dev);
>> + int ret;
>> +
>> + if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII) {
>> + /* Ensure PS-GTR PHY device used in SGMII mode is ready */
>> + struct phy *sgmii_phy = devm_phy_get(&pdev->dev, "sgmii-phy");
>> +
>> + if (IS_ERR(sgmii_phy)) {
>> + ret = PTR_ERR(sgmii_phy);
>> + dev_err_probe(&pdev->dev, ret,
>> + "failed to get PS-GTR PHY\n");
>> + return ret;
>> + }
>> +
>> + ret = phy_init(sgmii_phy);
>> + if (ret) {
>> + dev_err(&pdev->dev, "failed to init PS-GTR PHY: %d\n",
>> + ret);
>> + return ret;
>> + }
>
> I think reset below should be here to follow correct startup sequence.
If that's the case is the functionality still kept if moving phy_power_on()
in macb_open() and the correspondent phy_power_off() in macb_close() ?
Also, Robert, please handle the error path in this function (with calls to
phy_exit(), phy_power_off()) and PHY handling in macb_remove().
Thank you,
Claudiu Beznea
>
> Thanks,
> Michal
>
>
>> +
>> + ret = phy_power_on(sgmii_phy);
>> + if (ret) {
>> + dev_err(&pdev->dev, "failed to power on PS-GTR PHY:
>> %d\n",
>> + ret);
>> + return ret;
>> + }
>> + }
>> +
>> + /* Fully reset GEM controller at hardware level using zynqmp-reset
>> driver,
>> + * if mapped in device tree.
>> + */
>> + ret = device_reset_optional(&pdev->dev);
>> + if (ret) {
>> + dev_err_probe(&pdev->dev, ret, "failed to reset controller");
>> + return ret;
>> + }
>> +
>> + return macb_init(pdev);
>> +}
>> +
>> static const struct macb_usrio_config sama7g5_usrio = {
>> .mii = 0,
>> .rmii = 1,
>> @@ -4550,7 +4596,7 @@ static const struct macb_config zynqmp_config = {
>> MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH,
>> .dma_burst_length = 16,
>> .clk_init = macb_clk_init,
>> - .init = macb_init,
>> + .init = zynqmp_init,
>> .jumbo_max_len = 10240,
>> .usrio = &macb_default_usrio,
>> };
