diff options
Diffstat (limited to 'arch/s390/kernel/early_printk.c')
-rw-r--r-- | arch/s390/kernel/early_printk.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/s390/kernel/early_printk.c b/arch/s390/kernel/early_printk.c new file mode 100644 index 0000000..819cb15 --- /dev/null +++ b/arch/s390/kernel/early_printk.c @@ -0,0 +1,35 @@ +/* + * Copyright IBM Corp. 2017 + */ + +#include <linux/console.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <asm/sclp.h> + +static void sclp_early_write(struct console *con, const char *s, unsigned int len) +{ + __sclp_early_printk(s, len); +} + +static struct console sclp_early_console = { + .name = "earlysclp", + .write = sclp_early_write, + .flags = CON_PRINTBUFFER | CON_BOOT, + .index = -1, +}; + +static int __init setup_early_printk(char *buf) +{ + if (early_console) + return 0; + /* Accept only "earlyprintk" and "earlyprintk=sclp" */ + if (buf && strncmp(buf, "sclp", 4)) + return 0; + if (!sclp.has_linemode && !sclp.has_vt220) + return 0; + early_console = &sclp_early_console; + register_console(early_console); + return 0; +} +early_param("earlyprintk", setup_early_printk); |