If by BIOS or by other means the serial port is configured user might want to skip reconfiguration in the boot code.
Add support of 'nocfg' parameter to earlyprintk. Signed-off-by: Andy Shevchenko <[email protected]> --- arch/x86/boot/early_serial_console.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/arch/x86/boot/early_serial_console.c b/arch/x86/boot/early_serial_console.c index cfc9e55cd68a..5b4a81bf5d0e 100644 --- a/arch/x86/boot/early_serial_console.c +++ b/arch/x86/boot/early_serial_console.c @@ -80,9 +80,10 @@ static void early_serial_use_mmio_accessors(void) serial_out = mem8_serial_out; } -static void early_serial_init(unsigned long port, int baud) +static void early_serial_init(unsigned long port, int baud, bool configure) { - early_serial_configure(port, baud); + if (configure) + early_serial_configure(port, baud); early_serial_base = port; } @@ -101,12 +102,22 @@ static unsigned long parse_serial_port(const char *arg, int off, int *pos) return port; } +static bool parse_serial_configure(const char *arg, int off, int *pos) +{ + if (strncmp(arg + off, "nocfg", 5)) + return true; + + *pos = off + 5; + return false; +} + static void parse_earlyprintk(void) { int baud = DEFAULT_BAUD; char arg[64]; int pos = 0; unsigned long port = 0; + bool configure = true; if (cmdline_find_option("earlyprintk", arg, sizeof(arg)) > 0) { char *e; @@ -146,6 +157,11 @@ static void parse_earlyprintk(void) early_serial_use_io_accessors(); } + if (arg[pos] == ',') + pos++; + + configure = parse_serial_configure(arg, pos, &pos); + if (arg[pos] == ',') pos++; @@ -155,7 +171,7 @@ static void parse_earlyprintk(void) } if (port) - early_serial_init(port, baud); + early_serial_init(port, baud, configure); } #define BASE_BAUD (1843200/16) @@ -179,6 +195,7 @@ static void parse_console_uart8250(void) char optstr[64], *options; int baud = DEFAULT_BAUD; unsigned long port = 0; + bool configure = true; /* * console=uart8250,io,0x3f8,115200n8 @@ -204,7 +221,7 @@ static void parse_console_uart8250(void) baud = probe_baud(port); if (port) - early_serial_init(port, baud); + early_serial_init(port, baud, configure); } void console_init(void) -- 2.20.1
