Re: REG: TTC Timer

[Gowri Shankar]

Hi Konrad,

Thanks for your quick response.

Now I want to increment the TTC counter value to enable the system tick. How to configure the TTC register to increment it in QEMU.

I found the steps to enable the TTC counter which is below. But not able to increment. If possible could you please share the example source code?

  1. Select clock input source, set prescaler value (slcr.MIO_MUX_SEL registers, TTC Clock Control register). Ensure TTC is disabled (ttc.Counter_Control_x [DIS] = 1) before proceeding with this step. 

2. Set interval value (Interval register). This step is optional, for interval mode only. 

3. Set match value (Match registers). This step is optional, if matching is to be enabled. 

4. Enable interrupt (Interrupt Enable register). This step is optional, if interrupt is to be enabled.

5. Enable/disable waveform output, enable/disable matching, set counting direction, set mode, enable counter (TTC Counter Control register). This step starts the counter.  

Thanks & Regards,

P.Gowrishankar

On Mon, Dec 5, 2022 at 4:07 PM Konrad, Frederic <Frederic.Konrad@amd.com> wrote:

Hi Philippe,
Hi Gowri,

The zcu102 has a zynqmp soc object (hw/arm/xlnx-zcu102.c:125):

static void xlnx_zcu102_init(MachineState *machine)
{
...
    object_initialize_child(OBJECT(machine), "soc", &s->soc, TYPE_XLNX_ZYNQMP);

So the TTCs should work in the ZCU102.

Best Regards,
Fred

-----Original Message-----
From: Philippe Mathieu-Daudé <philmd@linaro.org>
Sent: 05 December 2022 09:24
To: Gowri Shankar <ggowri617@gmail.com>; QEMU Developers <qemu-devel@nongnu.org>; qemu-arm <qemu-arm@nongnu.org>
Cc: qemu-discuss@nongnu.org; Konrad, Frederic <Frederic.Konrad@amd.com>; Iglesias, Francisco <francisco.iglesias@amd.com>; Alistair Francis <alistair.francis@wdc.com>
Subject: Re: REG: TTC Timer

On 22/11/22 12:27, Gowri Shankar wrote:
> Hi Team,
>
> Advance Thanks for Your support.
>
> Could you please clarify one point here?
> I am using a Xilinx ZCU102 machine with QEMU7.1.0.
>
> I have seen QEMU 7.1.0 release has TTC timers for the Xilinx-zynqmp
> SoC model.
> url: https://wiki.qemu.org/ChangeLog/7.1
> <https://wiki.qemu.org/ChangeLog/7.1>
>
> In this case, can the ZCU102 machine also use the TTC feature?
> If yes and possible, Could you please share the example code snippet?
> --
> Thanks & Regards,
> P. Gowrishankar.
> +919944802490

Cc'ing qemu-arm@ mailing list and Xilinx ZCU102 machine developers.

--

Thanks & Regards,
P. Gowrishankar.
+919944802490