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Date:   Mon, 12 Jul 2021 23:27:08 +0300
From:   andy@surfacebook.localdomain
To:     Vignesh Raghavendra <vigneshr@ti.com>
Cc:     Jan Kiszka <jan.kiszka@siemens.com>,
        Tony Lindgren <tony@atomide.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
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        Linux ARM Mailing List <linux-arm-kernel@lists.infradead.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] serial: 8250: 8250_omap: Fix possible interrupt storm
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Tue, Jun 22, 2021 at 11:53:38AM +0530, Vignesh Raghavendra kirjoitti:
> On 6/22/21 11:45 AM, Jan Kiszka wrote:
> >>> Vignesh, it seems this quirk needs some soc specific flag added to
> >>> it maybe? Or maybe UART_OMAP_RX_LVL register is not available for
> >>> all the SoCs?
> >>>
> >> Yes indeed :(
> >>
> >>> I think it's best to drop this patch until the issues are resolved,
> >>> also there are some open comments above that might be answered by
> >>> limiting this quirk to a specific range of SoCs :)
> >>>
> >> Oops, I did test patch AM33xx assuming its equivalent to OMAP3, but UART
> >> IP is quite different. I will respin the patch making sure, workaround
> >> applies only to AM65x and K3 SoCs.
> >>
> >> Regards
> >> Vignesh
> >>
> > What's the status here for AM65x? The issue remains present on that
> > platform, and I was hoping to see a quick follow up that limit the fix
> > to that target.
> 
> Sorry for the delay, I am trying to find which other TI SoCs are
> affected by this issue. But that exercise will need a bit more time.
> Will send a fix to address K3 SoCs like AM65x today/tomo.

This all reminds me the very similar issue one found on Intel integrated
(Synopsys DesignWare based) UARTs:

https://lore.kernel.org/linux-serial/20170206233000.3021-1-dianders@chromium.org/
https://lore.kernel.org/linux-serial/1440015124-28393-1-git-send-email-california.l.sullivan@intel.com/

-- 
With Best Regards,
Andy Shevchenko