Commit d79fbb3a authored by Chris Packham's avatar Chris Packham Committed by Michael Ellerman
Browse files

powerpc: Support CMDLINE_EXTEND 



Bring powerpc in line with other architectures that support extending or
overriding the bootloader provided command line.

The current behaviour is most like CMDLINE_FROM_BOOTLOADER where the
bootloader command line is preferred but the kernel config can provide a
fallback so CMDLINE_FROM_BOOTLOADER is the default. CMDLINE_EXTEND can
be used to append the CMDLINE from the kernel config to the one provided
by the bootloader.

Signed-off-by: default avatarChris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190801225006.21952-1-chris.packham@alliedtelesis.co.nz
parent 6266a4da

arch/powerpc/Kconfig

+19 −1
Original line number Diff line number Diff line
@@ -874,15 +874,33 @@ config CMDLINE 
	  some command-line options at build time by entering them here.  In

	  most cases you will need to specify the root device here.



choice

	prompt "Kernel command line type" if CMDLINE != ""

	default CMDLINE_FROM_BOOTLOADER



config CMDLINE_FROM_BOOTLOADER

	bool "Use bootloader kernel arguments if available"

	help

	  Uses the command-line options passed by the boot loader. If

	  the boot loader doesn't provide any, the default kernel command

	  string provided in CMDLINE will be used.



config CMDLINE_EXTEND

	bool "Extend bootloader kernel arguments"

	help

	  The command-line arguments provided by the boot loader will be

	  appended to the default kernel command string.



config CMDLINE_FORCE

	bool "Always use the default kernel command string"

	depends on CMDLINE_BOOL

	help

	  Always use the default kernel command string, even if the boot

	  loader passes other arguments to the kernel.

	  This is useful if you cannot or don't want to change the

	  command-line options your boot loader passes to the kernel.



endchoice



config EXTRA_TARGETS

	string "Additional default image types"

	help

arch/powerpc/kernel/prom_init.c

+24 −12
Original line number Diff line number Diff line
@@ -303,16 +303,24 @@ static char __init *prom_strstr(const char *s1, const char *s2) 
	return NULL;

}



static size_t __init prom_strlcpy(char *dest, const char *src, size_t size)

static size_t __init prom_strlcat(char *dest, const char *src, size_t count)

{

	size_t ret = prom_strlen(src);

	size_t dsize = prom_strlen(dest);

	size_t len = prom_strlen(src);

	size_t res = dsize + len;



	if (size) {

		size_t len = (ret >= size) ? size - 1 : ret;

	/* This would be a bug */

	if (dsize >= count)

		return count;



	dest += dsize;

	count -= dsize;

	if (len >= count)

		len = count-1;

	memcpy(dest, src, len);

		dest[len] = '\0';

	}

	return ret;

	dest[len] = 0;

	return res;



}



#ifdef CONFIG_PPC_PSERIES
@@ -764,10 +772,14 @@ static void __init early_cmdline_parse(void) 


	prom_cmd_line[0] = 0;

	p = prom_cmd_line;

	if ((long)prom.chosen > 0)



	if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && (long)prom.chosen > 0)

		l = prom_getprop(prom.chosen, "bootargs", p, COMMAND_LINE_SIZE-1);

	if (IS_ENABLED(CONFIG_CMDLINE_BOOL) && (l <= 0 || p[0] == '\0')) /* dbl check */

		prom_strlcpy(prom_cmd_line, CONFIG_CMDLINE, sizeof(prom_cmd_line));



	if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) || l <= 0 || p[0] == '\0')

		prom_strlcat(prom_cmd_line, " " CONFIG_CMDLINE,

			     sizeof(prom_cmd_line));



	prom_printf("command line: %s\n", prom_cmd_line);



#ifdef CONFIG_PPC64

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