linux-kernel - Re: [PATCH v2 12/13] serial: sh-sci: Add support for RZ/G3E RSCI SCIF

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <19a08b75-13ca-45f9-884d-f96602336dfd@kernel.org>
Date: Fri, 31 Oct 2025 05:50:56 +0100
From: Jiri Slaby <jirislaby@...nel.org>
To: Biju <biju.das.au@...il.com>,
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc: Biju Das <biju.das.jz@...renesas.com>,
 Wolfram Sang <wsa+renesas@...g-engineering.com>,
 Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>,
 Geert Uytterhoeven <geert+renesas@...der.be>, linux-kernel@...r.kernel.org,
 linux-serial@...r.kernel.org, linux-renesas-soc@...r.kernel.org
Subject: Re: [PATCH v2 12/13] serial: sh-sci: Add support for RZ/G3E RSCI SCIF

Hi,

On 30. 10. 25, 18:58, Biju wrote:
> From: Biju Das <biju.das.jz@...renesas.com>
> 
> Add support for RZ/G3E RSCI SCIF(a.k.a FIFO mode). RSCI IP found on the
> RZ/G3E SoC is similar to RZ/T2H, but it has a 32-stage FIFO. it has 6
> clocks(5 module clocks + 1 external clock) instead of 3 clocks(2 module
> clocks + 1 external clock) on T2H and has multiple resets. Add support
> for the hardware flow control.
> 
> Signed-off-by: Biju Das <biju.das.jz@...renesas.com>
> ---
...
> --- a/drivers/tty/serial/rsci.c
> +++ b/drivers/tty/serial/rsci.c
> @@ -11,6 +11,8 @@
...
> +static void rsci_finish_console_write(struct uart_port *port, u32 ctrl)
> +{
> +	rsci_serial_out(port, CCR0, ctrl & ~CCR0_TE);
> +	cpu_relax();

What's the intent of cpu_relax in here? It does not make much sense to 
me. If you need delay, use delay.

> +	rsci_serial_out(port, CCR0, ctrl);
> +}
> +
...
> diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
> index fac83dace27c..85b89c1ebf15 100644
> --- a/drivers/tty/serial/sh-sci.c
> +++ b/drivers/tty/serial/sh-sci.c
> @@ -3397,7 +3397,7 @@ static void sci_remove(struct platform_device *dev)
>   	if (s->port.fifosize > 1)
>   		device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
>   	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF ||
> -	    type == SCI_PORT_RSCI)
> +	    type == SCI_PORT_RSCI || type == RSCI_PORT_SCIF)
>   		device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
...
> @@ -3759,7 +3763,8 @@ static int sci_probe(struct platform_device *dev)
>   			return ret;
>   	}
>   	if (sp->type == PORT_SCIFA || sp->type == PORT_SCIFB ||
> -	    sp->type == PORT_HSCIF || sp->type == SCI_PORT_RSCI) {
> +	    sp->type == PORT_HSCIF || sp->type == SCI_PORT_RSCI ||
> +	    sp->type == RSCI_PORT_SCIF) {

This test is duplicated -- you seem you need a helper for this.

thanks,
-- 
js
suse labs