* [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
@ 2012-06-21 8:56 Richard Genoud
2012-06-21 9:34 ` Florian Fainelli
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Richard Genoud @ 2012-06-21 8:56 UTC (permalink / raw)
To: linux-arm-kernel
This patch allows the ATAG_CMDLINE provided by the bootloader to be
concatenated to the bootargs property of the device tree.
This is useful to merge static values defined in the device tree with the
boot loader's (possibly) more dynamic values, such as startup reasons and more.
The bootloader should use the device tree to pass those values to the kernel,
but that's not always simple (old bootloader or very small one).
The behaviour is the same as the one introduced by Victor Boivie in
4394c1244249198c6b85093d46935b761b36ae05 by extending the CONFIG_CMDLINE.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
---
arch/arm/Kconfig | 19 +++++++++
arch/arm/boot/compressed/atags_to_fdt.c | 62 ++++++++++++++++++++++++++++++-
2 files changed, 79 insertions(+), 2 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 84449dd..ff4b6e6 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1959,6 +1959,25 @@ config ARM_ATAG_DTB_COMPAT
bootloaders, this option allows zImage to extract the information
from the ATAG list and store it at run time into the appended DTB.
+choice
+ prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
+ default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
+
+config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
+ bool "Use bootloader kernel arguments if available"
+ help
+ Uses the command-line options passed by the boot loader instead of
+ the device tree bootargs property. If the boot loader doesn't provide
+ any, the device tree bootargs property will be used.
+
+config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
+ bool "Extend with bootloader kernel arguments"
+ help
+ The command-line arguments provided by the boot loader will be
+ appended to the the device tree bootargs property.
+
+endchoice
+
config CMDLINE
string "Default kernel command string"
default ""
diff --git a/arch/arm/boot/compressed/atags_to_fdt.c b/arch/arm/boot/compressed/atags_to_fdt.c
index 797f04b..aabc02a 100644
--- a/arch/arm/boot/compressed/atags_to_fdt.c
+++ b/arch/arm/boot/compressed/atags_to_fdt.c
@@ -1,6 +1,12 @@
#include <asm/setup.h>
#include <libfdt.h>
+#if defined(CONFIG_ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND)
+#define do_extend_cmdline 1
+#else
+#define do_extend_cmdline 0
+#endif
+
static int node_offset(void *fdt, const char *node_path)
{
int offset = fdt_path_offset(fdt, node_path);
@@ -36,6 +42,48 @@ static int setprop_cell(void *fdt, const char *node_path,
return fdt_setprop_cell(fdt, offset, property, val);
}
+static const void *getprop(const void *fdt, const char *node_path,
+ const char *property, int *len)
+{
+ int offset = fdt_path_offset(fdt, node_path);
+
+ if (offset == -FDT_ERR_NOTFOUND)
+ return NULL;
+
+ return fdt_getprop(fdt, offset, property, len);
+}
+
+static void merge_fdt_bootargs(void *fdt, const char *fdt_cmdline)
+{
+ char cmdline[COMMAND_LINE_SIZE];
+ const char *fdt_bootargs;
+ char *ptr = cmdline;
+ int len = 0;
+
+ /* copy the fdt command line into the buffer */
+ fdt_bootargs = getprop(fdt, "/chosen", "bootargs", &len);
+ if (fdt_bootargs)
+ if (len < COMMAND_LINE_SIZE) {
+ memcpy(ptr, fdt_bootargs, len);
+ /* len is the length of the string
+ * including the NULL terminator */
+ ptr += len - 1;
+ }
+
+ /* and append the ATAG_CMDLINE */
+ if (fdt_cmdline) {
+ len = strlen(fdt_cmdline);
+ if (ptr - cmdline + len + 2 < COMMAND_LINE_SIZE) {
+ *ptr++ = ' ';
+ memcpy(ptr, fdt_cmdline, len);
+ ptr += len;
+ }
+ }
+ *ptr = '\0';
+
+ setprop_string(fdt, "/chosen", "bootargs", cmdline);
+}
+
/*
* Convert and fold provided ATAGs into the provided FDT.
*
@@ -72,8 +120,18 @@ int atags_to_fdt(void *atag_list, void *fdt, int total_space)
for_each_tag(atag, atag_list) {
if (atag->hdr.tag == ATAG_CMDLINE) {
- setprop_string(fdt, "/chosen", "bootargs",
- atag->u.cmdline.cmdline);
+ /* Append the ATAGS command line to the device tree
+ * command line.
+ * NB: This means that if the same parameter is set in
+ * the device tree and in the tags, the one from the
+ * tags will be chosen.
+ */
+ if (do_extend_cmdline)
+ merge_fdt_bootargs(fdt,
+ atag->u.cmdline.cmdline);
+ else
+ setprop_string(fdt, "/chosen", "bootargs",
+ atag->u.cmdline.cmdline);
} else if (atag->hdr.tag == ATAG_MEM) {
if (memcount >= sizeof(mem_reg_property)/4)
continue;
--
1.7.2.5
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
2012-06-21 8:56 [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE Richard Genoud
@ 2012-06-21 9:34 ` Florian Fainelli
2012-06-21 9:56 ` Richard Genoud
2012-06-21 9:40 ` Gregory CLEMENT
2012-06-21 16:05 ` Nicolas Pitre
2 siblings, 1 reply; 6+ messages in thread
From: Florian Fainelli @ 2012-06-21 9:34 UTC (permalink / raw)
To: linux-arm-kernel
Hello,
On Thursday 21 June 2012 10:56:57 Richard Genoud wrote:
> This patch allows the ATAG_CMDLINE provided by the bootloader to be
> concatenated to the bootargs property of the device tree.
>
> This is useful to merge static values defined in the device tree with the
> boot loader's (possibly) more dynamic values, such as startup reasons and
more.
>
> The bootloader should use the device tree to pass those values to the
kernel,
> but that's not always simple (old bootloader or very small one).
>
> The behaviour is the same as the one introduced by Victor Boivie in
> 4394c1244249198c6b85093d46935b761b36ae05 by extending the CONFIG_CMDLINE.
I had a similar need recently, and I was pointed at this more generic
solution: http://www.mail-archive.com/devicetree-
discuss at lists.ozlabs.org/msg10448.html
The only thing which is ARM-specific and not yet resolved is the following: if
you have ARM_ATAG_DTB_COMPAT enabled, the kernel command-line contains only
the bootloader supplied command-line and not bootloader + bootargs from DT. I
have not yet had a chance to get this sorted.
>
> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
> ---
> arch/arm/Kconfig | 19 +++++++++
> arch/arm/boot/compressed/atags_to_fdt.c | 62
++++++++++++++++++++++++++++++-
> 2 files changed, 79 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 84449dd..ff4b6e6 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -1959,6 +1959,25 @@ config ARM_ATAG_DTB_COMPAT
> bootloaders, this option allows zImage to extract the information
> from the ATAG list and store it at run time into the appended DTB.
>
> +choice
> + prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
> + default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
> +
> +config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
> + bool "Use bootloader kernel arguments if available"
> + help
> + Uses the command-line options passed by the boot loader instead of
> + the device tree bootargs property. If the boot loader doesn't provide
> + any, the device tree bootargs property will be used.
> +
> +config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
> + bool "Extend with bootloader kernel arguments"
> + help
> + The command-line arguments provided by the boot loader will be
> + appended to the the device tree bootargs property.
> +
> +endchoice
> +
> config CMDLINE
> string "Default kernel command string"
> default ""
> diff --git a/arch/arm/boot/compressed/atags_to_fdt.c
b/arch/arm/boot/compressed/atags_to_fdt.c
> index 797f04b..aabc02a 100644
> --- a/arch/arm/boot/compressed/atags_to_fdt.c
> +++ b/arch/arm/boot/compressed/atags_to_fdt.c
> @@ -1,6 +1,12 @@
> #include <asm/setup.h>
> #include <libfdt.h>
>
> +#if defined(CONFIG_ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND)
> +#define do_extend_cmdline 1
> +#else
> +#define do_extend_cmdline 0
> +#endif
> +
> static int node_offset(void *fdt, const char *node_path)
> {
> int offset = fdt_path_offset(fdt, node_path);
> @@ -36,6 +42,48 @@ static int setprop_cell(void *fdt, const char *node_path,
> return fdt_setprop_cell(fdt, offset, property, val);
> }
>
> +static const void *getprop(const void *fdt, const char *node_path,
> + const char *property, int *len)
> +{
> + int offset = fdt_path_offset(fdt, node_path);
> +
> + if (offset == -FDT_ERR_NOTFOUND)
> + return NULL;
> +
> + return fdt_getprop(fdt, offset, property, len);
> +}
> +
> +static void merge_fdt_bootargs(void *fdt, const char *fdt_cmdline)
> +{
> + char cmdline[COMMAND_LINE_SIZE];
> + const char *fdt_bootargs;
> + char *ptr = cmdline;
> + int len = 0;
> +
> + /* copy the fdt command line into the buffer */
> + fdt_bootargs = getprop(fdt, "/chosen", "bootargs", &len);
> + if (fdt_bootargs)
> + if (len < COMMAND_LINE_SIZE) {
> + memcpy(ptr, fdt_bootargs, len);
> + /* len is the length of the string
> + * including the NULL terminator */
> + ptr += len - 1;
> + }
> +
> + /* and append the ATAG_CMDLINE */
> + if (fdt_cmdline) {
> + len = strlen(fdt_cmdline);
> + if (ptr - cmdline + len + 2 < COMMAND_LINE_SIZE) {
> + *ptr++ = ' ';
> + memcpy(ptr, fdt_cmdline, len);
> + ptr += len;
> + }
> + }
> + *ptr = '\0';
> +
> + setprop_string(fdt, "/chosen", "bootargs", cmdline);
> +}
> +
> /*
> * Convert and fold provided ATAGs into the provided FDT.
> *
> @@ -72,8 +120,18 @@ int atags_to_fdt(void *atag_list, void *fdt, int
total_space)
>
> for_each_tag(atag, atag_list) {
> if (atag->hdr.tag == ATAG_CMDLINE) {
> - setprop_string(fdt, "/chosen", "bootargs",
> - atag->u.cmdline.cmdline);
> + /* Append the ATAGS command line to the device tree
> + * command line.
> + * NB: This means that if the same parameter is set in
> + * the device tree and in the tags, the one from the
> + * tags will be chosen.
> + */
> + if (do_extend_cmdline)
> + merge_fdt_bootargs(fdt,
> + atag->u.cmdline.cmdline);
> + else
> + setprop_string(fdt, "/chosen", "bootargs",
> + atag->u.cmdline.cmdline);
> } else if (atag->hdr.tag == ATAG_MEM) {
> if (memcount >= sizeof(mem_reg_property)/4)
> continue;
> --
> 1.7.2.5
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
2012-06-21 8:56 [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE Richard Genoud
2012-06-21 9:34 ` Florian Fainelli
@ 2012-06-21 9:40 ` Gregory CLEMENT
2012-06-21 16:05 ` Nicolas Pitre
2 siblings, 0 replies; 6+ messages in thread
From: Gregory CLEMENT @ 2012-06-21 9:40 UTC (permalink / raw)
To: linux-arm-kernel
On 06/21/2012 10:56 AM, Richard Genoud wrote:
> This patch allows the ATAG_CMDLINE provided by the bootloader to be
> concatenated to the bootargs property of the device tree.
>
> This is useful to merge static values defined in the device tree with the
> boot loader's (possibly) more dynamic values, such as startup reasons and more.
>
> The bootloader should use the device tree to pass those values to the kernel,
> but that's not always simple (old bootloader or very small one).
>
> The behaviour is the same as the one introduced by Victor Boivie in
> 4394c1244249198c6b85093d46935b761b36ae05 by extending the CONFIG_CMDLINE.
>
> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Hi Richard,
I have tested both option on a Armada XP dev board. It worked as expected.
You can add:
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> ---
> arch/arm/Kconfig | 19 +++++++++
> arch/arm/boot/compressed/atags_to_fdt.c | 62 ++++++++++++++++++++++++++++++-
> 2 files changed, 79 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 84449dd..ff4b6e6 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -1959,6 +1959,25 @@ config ARM_ATAG_DTB_COMPAT
> bootloaders, this option allows zImage to extract the information
> from the ATAG list and store it at run time into the appended DTB.
>
> +choice
> + prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
> + default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
> +
> +config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
> + bool "Use bootloader kernel arguments if available"
> + help
> + Uses the command-line options passed by the boot loader instead of
> + the device tree bootargs property. If the boot loader doesn't provide
> + any, the device tree bootargs property will be used.
> +
> +config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
> + bool "Extend with bootloader kernel arguments"
> + help
> + The command-line arguments provided by the boot loader will be
> + appended to the the device tree bootargs property.
> +
> +endchoice
> +
> config CMDLINE
> string "Default kernel command string"
> default ""
> diff --git a/arch/arm/boot/compressed/atags_to_fdt.c b/arch/arm/boot/compressed/atags_to_fdt.c
> index 797f04b..aabc02a 100644
> --- a/arch/arm/boot/compressed/atags_to_fdt.c
> +++ b/arch/arm/boot/compressed/atags_to_fdt.c
> @@ -1,6 +1,12 @@
> #include <asm/setup.h>
> #include <libfdt.h>
>
> +#if defined(CONFIG_ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND)
> +#define do_extend_cmdline 1
> +#else
> +#define do_extend_cmdline 0
> +#endif
> +
> static int node_offset(void *fdt, const char *node_path)
> {
> int offset = fdt_path_offset(fdt, node_path);
> @@ -36,6 +42,48 @@ static int setprop_cell(void *fdt, const char *node_path,
> return fdt_setprop_cell(fdt, offset, property, val);
> }
>
> +static const void *getprop(const void *fdt, const char *node_path,
> + const char *property, int *len)
> +{
> + int offset = fdt_path_offset(fdt, node_path);
> +
> + if (offset == -FDT_ERR_NOTFOUND)
> + return NULL;
> +
> + return fdt_getprop(fdt, offset, property, len);
> +}
> +
> +static void merge_fdt_bootargs(void *fdt, const char *fdt_cmdline)
> +{
> + char cmdline[COMMAND_LINE_SIZE];
> + const char *fdt_bootargs;
> + char *ptr = cmdline;
> + int len = 0;
> +
> + /* copy the fdt command line into the buffer */
> + fdt_bootargs = getprop(fdt, "/chosen", "bootargs", &len);
> + if (fdt_bootargs)
> + if (len < COMMAND_LINE_SIZE) {
> + memcpy(ptr, fdt_bootargs, len);
> + /* len is the length of the string
> + * including the NULL terminator */
> + ptr += len - 1;
> + }
> +
> + /* and append the ATAG_CMDLINE */
> + if (fdt_cmdline) {
> + len = strlen(fdt_cmdline);
> + if (ptr - cmdline + len + 2 < COMMAND_LINE_SIZE) {
> + *ptr++ = ' ';
> + memcpy(ptr, fdt_cmdline, len);
> + ptr += len;
> + }
> + }
> + *ptr = '\0';
> +
> + setprop_string(fdt, "/chosen", "bootargs", cmdline);
> +}
> +
> /*
> * Convert and fold provided ATAGs into the provided FDT.
> *
> @@ -72,8 +120,18 @@ int atags_to_fdt(void *atag_list, void *fdt, int total_space)
>
> for_each_tag(atag, atag_list) {
> if (atag->hdr.tag == ATAG_CMDLINE) {
> - setprop_string(fdt, "/chosen", "bootargs",
> - atag->u.cmdline.cmdline);
> + /* Append the ATAGS command line to the device tree
> + * command line.
> + * NB: This means that if the same parameter is set in
> + * the device tree and in the tags, the one from the
> + * tags will be chosen.
> + */
> + if (do_extend_cmdline)
> + merge_fdt_bootargs(fdt,
> + atag->u.cmdline.cmdline);
> + else
> + setprop_string(fdt, "/chosen", "bootargs",
> + atag->u.cmdline.cmdline);
> } else if (atag->hdr.tag == ATAG_MEM) {
> if (memcount >= sizeof(mem_reg_property)/4)
> continue;
--
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com
+33 602 196 044
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
2012-06-21 9:34 ` Florian Fainelli
@ 2012-06-21 9:56 ` Richard Genoud
0 siblings, 0 replies; 6+ messages in thread
From: Richard Genoud @ 2012-06-21 9:56 UTC (permalink / raw)
To: linux-arm-kernel
2012/6/21 Florian Fainelli <florian@openwrt.org>:
> The only thing which is ARM-specific and not yet resolved is the following: if
> you have ARM_ATAG_DTB_COMPAT enabled, the kernel command-line contains only
> the bootloader supplied command-line and not bootloader + bootargs from DT. I
> have not yet had a chance to get this sorted.
That's the whole point of this patch : to have bootloader + bootargs
from DT when ARM_ATAG_DTB_COMPAT is enabled.
Richard.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
2012-06-21 8:56 [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE Richard Genoud
2012-06-21 9:34 ` Florian Fainelli
2012-06-21 9:40 ` Gregory CLEMENT
@ 2012-06-21 16:05 ` Nicolas Pitre
2012-06-26 17:34 ` Richard Genoud
2 siblings, 1 reply; 6+ messages in thread
From: Nicolas Pitre @ 2012-06-21 16:05 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, 21 Jun 2012, Richard Genoud wrote:
> This patch allows the ATAG_CMDLINE provided by the bootloader to be
> concatenated to the bootargs property of the device tree.
>
> This is useful to merge static values defined in the device tree with the
> boot loader's (possibly) more dynamic values, such as startup reasons and more.
>
> The bootloader should use the device tree to pass those values to the kernel,
> but that's not always simple (old bootloader or very small one).
>
> The behaviour is the same as the one introduced by Victor Boivie in
> 4394c1244249198c6b85093d46935b761b36ae05 by extending the CONFIG_CMDLINE.
>
> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
> ---
> arch/arm/Kconfig | 19 +++++++++
> arch/arm/boot/compressed/atags_to_fdt.c | 62 ++++++++++++++++++++++++++++++-
> 2 files changed, 79 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 84449dd..ff4b6e6 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -1959,6 +1959,25 @@ config ARM_ATAG_DTB_COMPAT
> bootloaders, this option allows zImage to extract the information
> from the ATAG list and store it at run time into the appended DTB.
>
> +choice
> + prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
> + default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
> +
> +config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
> + bool "Use bootloader kernel arguments if available"
> + help
> + Uses the command-line options passed by the boot loader instead of
> + the device tree bootargs property. If the boot loader doesn't provide
> + any, the device tree bootargs property will be used.
> +
> +config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
> + bool "Extend with bootloader kernel arguments"
> + help
> + The command-line arguments provided by the boot loader will be
> + appended to the the device tree bootargs property.
> +
> +endchoice
> +
> config CMDLINE
> string "Default kernel command string"
> default ""
> diff --git a/arch/arm/boot/compressed/atags_to_fdt.c b/arch/arm/boot/compressed/atags_to_fdt.c
> index 797f04b..aabc02a 100644
> --- a/arch/arm/boot/compressed/atags_to_fdt.c
> +++ b/arch/arm/boot/compressed/atags_to_fdt.c
> @@ -1,6 +1,12 @@
> #include <asm/setup.h>
> #include <libfdt.h>
>
> +#if defined(CONFIG_ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND)
> +#define do_extend_cmdline 1
> +#else
> +#define do_extend_cmdline 0
> +#endif
> +
> static int node_offset(void *fdt, const char *node_path)
> {
> int offset = fdt_path_offset(fdt, node_path);
> @@ -36,6 +42,48 @@ static int setprop_cell(void *fdt, const char *node_path,
> return fdt_setprop_cell(fdt, offset, property, val);
> }
>
> +static const void *getprop(const void *fdt, const char *node_path,
> + const char *property, int *len)
> +{
> + int offset = fdt_path_offset(fdt, node_path);
> +
> + if (offset == -FDT_ERR_NOTFOUND)
> + return NULL;
> +
> + return fdt_getprop(fdt, offset, property, len);
> +}
> +
> +static void merge_fdt_bootargs(void *fdt, const char *fdt_cmdline)
> +{
> + char cmdline[COMMAND_LINE_SIZE];
> + const char *fdt_bootargs;
> + char *ptr = cmdline;
> + int len = 0;
> +
> + /* copy the fdt command line into the buffer */
> + fdt_bootargs = getprop(fdt, "/chosen", "bootargs", &len);
> + if (fdt_bootargs)
> + if (len < COMMAND_LINE_SIZE) {
> + memcpy(ptr, fdt_bootargs, len);
> + /* len is the length of the string
> + * including the NULL terminator */
> + ptr += len - 1;
> + }
> +
> + /* and append the ATAG_CMDLINE */
> + if (fdt_cmdline) {
> + len = strlen(fdt_cmdline);
> + if (ptr - cmdline + len + 2 < COMMAND_LINE_SIZE) {
> + *ptr++ = ' ';
> + memcpy(ptr, fdt_cmdline, len);
> + ptr += len;
> + }
> + }
> + *ptr = '\0';
> +
> + setprop_string(fdt, "/chosen", "bootargs", cmdline);
> +}
> +
> /*
> * Convert and fold provided ATAGs into the provided FDT.
> *
> @@ -72,8 +120,18 @@ int atags_to_fdt(void *atag_list, void *fdt, int total_space)
>
> for_each_tag(atag, atag_list) {
> if (atag->hdr.tag == ATAG_CMDLINE) {
> - setprop_string(fdt, "/chosen", "bootargs",
> - atag->u.cmdline.cmdline);
> + /* Append the ATAGS command line to the device tree
> + * command line.
> + * NB: This means that if the same parameter is set in
> + * the device tree and in the tags, the one from the
> + * tags will be chosen.
> + */
> + if (do_extend_cmdline)
> + merge_fdt_bootargs(fdt,
> + atag->u.cmdline.cmdline);
> + else
> + setprop_string(fdt, "/chosen", "bootargs",
> + atag->u.cmdline.cmdline);
> } else if (atag->hdr.tag == ATAG_MEM) {
> if (memcount >= sizeof(mem_reg_property)/4)
> continue;
> --
> 1.7.2.5
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
2012-06-21 16:05 ` Nicolas Pitre
@ 2012-06-26 17:34 ` Richard Genoud
0 siblings, 0 replies; 6+ messages in thread
From: Richard Genoud @ 2012-06-26 17:34 UTC (permalink / raw)
To: linux-arm-kernel
2012/6/21 Nicolas Pitre <nicolas.pitre@linaro.org>:
> On Thu, 21 Jun 2012, Richard Genoud wrote:
>
>> This patch allows the ATAG_CMDLINE provided by the bootloader to be
>> concatenated to the bootargs property of the device tree.
>>
>> This is useful to merge static values defined in the device tree with the
>> boot loader's (possibly) more dynamic values, such as startup reasons and more.
>>
>> The bootloader should use the device tree to pass those values to the kernel,
>> but that's not always simple (old bootloader or very small one).
>>
>> The behaviour is the same as the one introduced by Victor Boivie in
>> 4394c1244249198c6b85093d46935b761b36ae05 by extending the CONFIG_CMDLINE.
>>
>> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
>
> Acked-by: Nicolas Pitre <nico@linaro.org>
As it has been acked by Nicolas, I sent it to the Russell's patch subsystem :
http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=7437/1
Richard.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-06-26 17:34 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-06-21 8:56 [PATCH] ARM: zImage: Allow DTB command line concatenation with ATAG_CMDLINE Richard Genoud
2012-06-21 9:34 ` Florian Fainelli
2012-06-21 9:56 ` Richard Genoud
2012-06-21 9:40 ` Gregory CLEMENT
2012-06-21 16:05 ` Nicolas Pitre
2012-06-26 17:34 ` Richard Genoud
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