On 10/09/21, Michal Simek wrote:

Hi,

On 9/8/21 5:39 PM, Jorge Ramirez-Ortiz, Foundries wrote:

...

Hi Michal

The *linux* cadence_wdt driver for the watchdog enables the clock that controls its behaviour. However this is not done in the U-boot driver; I dont think it is safe to assume that the clock will be active. do you know why is the driver making that assumption? and how to enable the clock?

Also, I am not sure it is either safe to assume that the WDT IP will be enabled; IMO during probe we should do something like this (otherwise the AXI bus will complain and fault the boot)

static int cdns_wdt_probe(struct udevice *dev) {

• debug("%s: Probing wdt%u\n", __func__, dev_seq(dev));

• u32 rst = 0;

• /* release WDT from reset */

• rst = readl(0xFD1A0100) & ~BIT(15);

• writel(rst, 0xFD1A0100);

• debug("%s: Probing wdt%u)\n", __func__, dev_seq(dev));

    return 0;
  

}

If reset should be perform it should be done via drivers/reset/reset-zynqmp.c

ok

It means when you define it in DT you will get reset.

makes sene

I am ok to wire all resets for all IPs to make sure that they are in proper state but this has to be tested first.

all right. but yes this particular case was tested.

Thanks, Michal

-- Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91 w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel - Xilinx Microblaze Maintainer of Linux kernel - Xilinx Zynq ARM and ZynqMP ARM64 SoCs U-Boot custodian - Xilinx Microblaze/Zynq/ZynqMP/Versal SoCs