From: Ahmad Fatoum <a.fatoum@pengutronix.de>
To: Du Huanpeng <u74147@gmail.com>
Cc: barebox@lists.infradead.org
Subject: Re: [PATCH] MIPS: DEBUG_LL_UART_DIVISOR is 0, use a0 instead
Date: Fri, 25 Sep 2020 19:54:12 +0200 [thread overview]
Message-ID: <1f4b3092-7941-17ec-11f9-ce76362561b1@pengutronix.de> (raw)
In-Reply-To: <20200925164259.GA21154@black>
Hello Du,
On 9/25/20 6:42 PM, Du Huanpeng wrote:
> Hi, How about this, I send this for review, if it is ok,
> I will send a patch later.
>
> I add a argument to the macro, and set a default parameter.
>
> +.macro debug_ll_ns16550_init divisor=DEBUG_LL_UART_DIVISOR
Sounds great! Much less error prone IMO.
>
>
> + /* three forms for ``call'' the macro */
> pass a register name
> + debug_ll_ns16550_init v0
>
> pass a immediate number
> + debug_ll_ns16550_init 888
>
> use this macro as usual before
> + debug_ll_ns16550_init
>
> ----8<-----
>
> diff --git a/arch/mips/boards/loongson-ls1b/lowlevel.S b/arch/mips/boards/loongson-ls1b/lowlevel.S
> index af6ad54e1..7120d80ef 100644
> --- a/arch/mips/boards/loongson-ls1b/lowlevel.S
> +++ b/arch/mips/boards/loongson-ls1b/lowlevel.S
> @@ -28,8 +28,14 @@ ENTRY_FUNCTION(BOARD_PBL_START)
>
> pbl_loongson1_uart_enable
> pbl_loongson1_calc_prescale 115200
> - move a0, v0
> +
> + /* three forms for ``call'' the macro */
> + debug_ll_ns16550_init v0
> + debug_ll_ns16550_init 888
> + debug_ll_ns16550_init
> +
> debug_ll_ns16550_init
> +
> debug_ll_ns16550_outnl
> debug_ll_outc '.'
> debug_ll_ns16550_outnl
> diff --git a/arch/mips/include/asm/debug_ll_ns16550.h b/arch/mips/include/asm/debug_ll_ns16550.h
> index a33587a15..44f3d5976 100644
> --- a/arch/mips/include/asm/debug_ll_ns16550.h
> +++ b/arch/mips/include/asm/debug_ll_ns16550.h
> @@ -58,17 +58,14 @@ static inline void PUTC_LL(char ch)
> * Macros for use in assembly language code
> */
>
> -.macro debug_ll_ns16550_init
> +.macro debug_ll_ns16550_init divisor=DEBUG_LL_UART_DIVISOR
> #ifdef CONFIG_DEBUG_LL
> la t0, DEBUG_LL_UART_ADDR
>
> li t1, UART_LCR_DLAB /* DLAB on */
> sb t1, UART_LCR(t0) /* Write it out */
>
> - li t1, DEBUG_LL_UART_DIVISOR
> -#if DEBUG_LL_UART_DIVISOR == 0
> - move t1, a0
> -#endif
> + add t1, zero, \divisor
> sb t1, UART_DLL(t0) /* write low order byte */
> srl t1, t1, 8
> sb t1, UART_DLM(t0) /* write high order byte */
>
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox
prev parent reply other threads:[~2020-09-25 17:54 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-11 12:33 [PATCH] MIPS: loongson1: enable to run from spi flash Du Huanpeng
2020-09-11 12:33 ` [PATCH] MIPS: DEBUG_LL_UART_DIVISOR is 0, use a0 instead Du Huanpeng
2020-09-11 14:07 ` Ahmad Fatoum
2020-09-17 13:56 ` Du Huanpeng
2020-09-17 17:42 ` Ahmad Fatoum
2020-09-25 16:42 ` Du Huanpeng
2020-09-25 17:54 ` Ahmad Fatoum [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1f4b3092-7941-17ec-11f9-ce76362561b1@pengutronix.de \
--to=a.fatoum@pengutronix.de \
--cc=barebox@lists.infradead.org \
--cc=u74147@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox