Re: [PATCH] powerpc: Fix mem= cmdline handling on arch/powerpc for !MULTIPLATFORM

From: Michael Ellerman
Date: Fri Feb 24 2006 - 17:25:48 EST


Hi Kumar,

On Sat, 25 Feb 2006 03:54, Kumar Gala wrote:
> mem= command line option was being ignored in arch/powerpc if we were not
> a CONFIG_MULTIPLATFORM (which is handled via prom_init stub). The initial
> command line extraction and parsing needed to be moved earlier in the boot
> process and have code to actual parse mem= and do something about it.

> @@ -1004,6 +991,41 @@ static int __init early_init_dt_scan_cho
> crashk_res.end = crashk_res.start + *lprop - 1;
> #endif
>
> + /* Retreive command line */
> + p = of_get_flat_dt_prop(node, "bootargs", &l);
> + if (p != NULL && l > 0)
> + strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
> +
> +#ifdef CONFIG_CMDLINE
> + if (l == 0 || (l == 1 && (*p) == 0))
> + strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
> +#endif /* CONFIG_CMDLINE */
> +
> + DBG("Command line is: %s\n", cmd_line);
> +
> + if (strstr(cmd_line, "mem=")) {
> + char *p, *q;
> + unsigned long maxmem = 0;
> +
> + for (q = cmd_line; (p = strstr(q, "mem=")) != 0; ) {
> + q = p + 4;
> + if (p > cmd_line && p[-1] != ' ')
> + continue;
> + maxmem = simple_strtoul(q, &q, 0);
> + if (*q == 'k' || *q == 'K') {
> + maxmem <<= 10;
> + ++q;
> + } else if (*q == 'm' || *q == 'M') {
> + maxmem <<= 20;
> + ++q;
> + } else if (*q == 'g' || *q == 'G') {
> + maxmem <<= 30;
> + ++q;
> + }
> + }
> + memory_limit = maxmem;
> + }
> +

Why not make the mem= parsing an early_param() handler and then call
parse_early_param() here?

And I think a switch would be easier to read for the K/M/G handling.

cheers

--
Michael Ellerman
IBM OzLabs

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person

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