From: Max Filippov Date: Tue, 22 Sep 2015 12:20:32 +0000 (+0300) Subject: serial_core: support native endianness X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d215d80957ce98c318064c249ad0b7800c63a19d;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git serial_core: support native endianness There are three natural ways in which devices may be wired to the system: little endian (device receives correctly ordered bits of a word written by little-endian CPU to its register, but big-endian CPU needs to swap bytes of a word before writing it), big endian (same, but with big-endian CPU in more favourable position) and native endian (CPU of either endianness may do word-sized I/O without need for byteswapping). Adding an option for native endianness allows using single kernel command line for boards with native-endian serial ports on bi-endian architectures. This goes in parallel with 'native-endian' DTS attribute. Signed-off-by: Max Filippov Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 603d2cc3f424..df4271ae7414 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -1819,8 +1819,8 @@ uart_get_console(struct uart_port *ports, int nr, struct console *co) * @options: ptr for field; NULL if not present (out) * * Decodes earlycon kernel command line parameters of the form - * earlycon=,io|mmio|mmio32|mmio32be,, - * console=,io|mmio|mmio32|mmio32be,, + * earlycon=,io|mmio|mmio32|mmio32be|mmio32native,, + * console=,io|mmio|mmio32|mmio32be|mmio32native,, * * The optional form * earlycon=,0x, @@ -1841,6 +1841,10 @@ int uart_parse_earlycon(char *p, unsigned char *iotype, unsigned long *addr, } else if (strncmp(p, "mmio32be,", 9) == 0) { *iotype = UPIO_MEM32BE; p += 9; + } else if (strncmp(p, "mmio32native,", 13) == 0) { + *iotype = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) ? + UPIO_MEM32BE : UPIO_MEM32; + p += 13; } else if (strncmp(p, "io,", 3) == 0) { *iotype = UPIO_PORT; p += 3;