diff mbox series

[DO,NOT,MERGE,v5,06/37] sh: kernel/setup Update DT support.

Message ID 76bbd45b22ef6cc1fa69369aff908c9c4e366860.1701768028.git.ysato@users.sourceforge.jp (mailing list archive)
State Not Applicable, archived
Headers show
Series Device Tree support for SH7751 based board | expand

Commit Message

Yoshinori Sato Dec. 5, 2023, 9:45 a.m. UTC 
Fix extrnal fdt initialize and bootargs.

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
---
 arch/sh/kernel/setup.c | 51 ++++++++++++++++++++++++++++--------------
 1 file changed, 34 insertions(+), 17 deletions(-)

Comments

Arnd Bergmann Dec. 5, 2023, 1:14 p.m. UTC | #1 
On Tue, Dec 5, 2023, at 10:45, Yoshinori Sato wrote:
> Fix extrnal fdt initialize and bootargs.
>
> Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
> ---
>  arch/sh/kernel/setup.c | 51 ++++++++++++++++++++++++++++--------------
>  1 file changed, 34 insertions(+), 17 deletions(-)
>
> diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c
> index 3d80515298d2..b299abff68e0 100644
> --- a/arch/sh/kernel/setup.c
> +++ b/arch/sh/kernel/setup.c
> @@ -30,6 +30,7 @@
>  #include <linux/memblock.h>
>  #include <linux/of.h>
>  #include <linux/of_fdt.h>
> +#include <linux/libfdt.h>
>  #include <linux/uaccess.h>
>  #include <uapi/linux/mount.h>
>  #include <asm/io.h>
> @@ -74,7 +75,13 @@ extern int root_mountflags;
>  #define RAMDISK_PROMPT_FLAG		0x8000
>  #define RAMDISK_LOAD_FLAG		0x4000
> 
> +#if defined(CONFIG_OF) && !defined(CONFIG_USE_BUILTIN_DTB)
> +#define CHOSEN_BOOTARGS
> +#endif
> +
> +#ifndef CHOSEN_BOOTARGS
>  static char __initdata command_line[COMMAND_LINE_SIZE] = { 0, };
> +#endif

I think an appended DTB is generally better than a built-in
one, as that allows you to still have a single kernel
image across machines and just pick the dtb when installing it.

With everything else being equal, I would suggest not
actually making this an option for new platforms.

    Arnd
diff mbox series

Patch

diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c
index 3d80515298d2..b299abff68e0 100644
--- a/arch/sh/kernel/setup.c
+++ b/arch/sh/kernel/setup.c
@@ -30,6 +30,7 @@ 
 #include <linux/memblock.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
+#include <linux/libfdt.h>
 #include <linux/uaccess.h>
 #include <uapi/linux/mount.h>
 #include <asm/io.h>
@@ -74,7 +75,13 @@  extern int root_mountflags;
 #define RAMDISK_PROMPT_FLAG		0x8000
 #define RAMDISK_LOAD_FLAG		0x4000
 
+#if defined(CONFIG_OF) && !defined(CONFIG_USE_BUILTIN_DTB)
+#define CHOSEN_BOOTARGS
+#endif
+
+#ifndef CHOSEN_BOOTARGS
 static char __initdata command_line[COMMAND_LINE_SIZE] = { 0, };
+#endif
 
 static struct resource code_resource = {
 	.name = "Kernel code",
@@ -244,18 +251,18 @@  void __init __weak plat_early_device_setup(void)
 void __ref sh_fdt_init(phys_addr_t dt_phys)
 {
 	static int done = 0;
-	void *dt_virt;
+	void *fdt;
 
 	/* Avoid calling an __init function on secondary cpus. */
 	if (done) return;
 
 #ifdef CONFIG_USE_BUILTIN_DTB
-	dt_virt = __dtb_start;
+	fdt = __dtb_start;
 #else
-	dt_virt = phys_to_virt(dt_phys);
+	fdt = phys_to_virt(dt_phys);
 #endif
 
-	if (!dt_virt || !early_init_dt_scan(dt_virt)) {
+	if (!fdt || !early_init_dt_scan(fdt)) {
 		pr_crit("Error: invalid device tree blob"
 			" at physical address %p\n", (void *)dt_phys);
 
@@ -269,8 +276,20 @@  void __ref sh_fdt_init(phys_addr_t dt_phys)
 
 void __init setup_arch(char **cmdline_p)
 {
+#ifdef CONFIG_OF_EARLY_FLATTREE
+	if (IS_ENABLED(CONFIG_USE_BUILTIN_DTB)) {
+		/* Relocate Embedded DTB */
+		unflatten_and_copy_device_tree();
+	} else if (initial_boot_params) {
+		/* Reserve external DTB area */
+		memblock_reserve(__pa(initial_boot_params),
+				 fdt_totalsize(initial_boot_params));
+		unflatten_device_tree();
+	}
+#endif
 	enable_mmu();
 
+#ifndef CONFIG_OF
 	ROOT_DEV = old_decode_dev(ORIG_ROOT_DEV);
 
 	printk(KERN_NOTICE "Boot params:\n"
@@ -299,19 +318,25 @@  void __init setup_arch(char **cmdline_p)
 	bss_resource.start = virt_to_phys(__bss_start);
 	bss_resource.end = virt_to_phys(__bss_stop)-1;
 
-#ifdef CONFIG_CMDLINE_OVERWRITE
-	strscpy(command_line, CONFIG_CMDLINE, sizeof(command_line));
-#else
+#endif
+
+#ifndef CHOSEN_BOOTARGS
+#ifndef CONFIG_CMDLINE_OVERWRITE
 	strscpy(command_line, COMMAND_LINE, sizeof(command_line));
 #ifdef CONFIG_CMDLINE_EXTEND
 	strlcat(command_line, " ", sizeof(command_line));
 	strlcat(command_line, CONFIG_CMDLINE, sizeof(command_line));
 #endif
-#endif
-
+#else   /* !CONFIG_CMDLINE_OVERWRITE*/
+	strscpy(command_line, CONFIG_CMDLINE, sizeof(command_line));
+#endif  /* CONFIG_CMDLINE_OVERWRITE */
 	/* Save unparsed command line copy for /proc/cmdline */
 	memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
 	*cmdline_p = command_line;
+#else	/* CHOSEN_BOOTARGS */
+	/* Use "/chosen/bootargs" specified in devicetree. */
+	*cmdline_p = boot_command_line;
+#endif
 
 	parse_early_param();
 
@@ -322,14 +347,6 @@  void __init setup_arch(char **cmdline_p)
 	/* Let earlyprintk output early console messages */
 	sh_early_platform_driver_probe("earlyprintk", 1, 1);
 
-#ifdef CONFIG_OF_EARLY_FLATTREE
-#ifdef CONFIG_USE_BUILTIN_DTB
-	unflatten_and_copy_device_tree();
-#else
-	unflatten_device_tree();
-#endif
-#endif
-
 	paging_init();
 
 	/* Perform the machine specific initialisation */