lkml.org 
[lkml]   [2022]   [Aug]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/2 v5] regmap: Support accelerated noinc operations
On Tue, Aug 16, 2022 at 10:48:31PM +0200, Linus Walleij wrote:
> Several architectures have accelerated operations for MMIO
> operations writing to a single register, such as writesb, writesw,
> writesl, writesq, readsb, readsw, readsl and readsq but regmap
> currently cannot use them because we have no hooks for providing
> an accelerated noinc back-end for MMIO.
>
> Solve this by providing reg_[read/write]_noinc callbacks for
> the bus abstraction, so that the regmap-mmio bus can use this.
>
> Currently I do not see a need to support this for custom regmaps
> so it is only added to the bus.
>
> Callbacks are passed a void * with the array of values and a
> count which is the number of items of the byte chunk size for
> the specific register width.

I see these applied, but consider below for the possible followups.

...

> + ret = regcache_write(map, reg, lastval);
> + if (ret != 0)

if (ret) ?

> + return ret;

...

> + dev_info(map->dev, "%x %s [", reg, write ? "<=" : "=>");
> + for (i = 0; i < val_len; i++) {
> + switch (val_bytes) {
> + case 1:
> + pr_cont("%x", u8p[i]);
> + break;
> + case 2:
> + pr_cont("%x", u16p[i]);
> + break;
> + case 4:
> + pr_cont("%x", u32p[i]);
> + break;
> +#ifdef CONFIG_64BIT
> + case 8:
> + pr_cont("%llx", u64p[i]);
> + break;
> +#endif
> + default:
> + break;
> + }
> + if (i == (val_len - 1))
> + pr_cont("]\n");
> + else
> + pr_cont(",");
> + }

I'm wondering why we can't use hex_dump_to_buffer() approach? Or even better,
introduce eventually dev_hex_dump() (as it's done for seq_file and printk)
and use it.

--
With Best Regards,
Andy Shevchenko


\
 
 \ /
  Last update: 2022-08-30 18:36    [W:0.085 / U:0.628 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site