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author | Mark A. Greer <mgreer@mvista.com> | 2006-10-16 20:52:09 (GMT) |
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committer | Paul Mackerras <paulus@samba.org> | 2006-10-23 02:49:19 (GMT) |
commit | 0c176fa80fdfa9b4e0753e37223b056994c818d2 (patch) | |
tree | aa45e2bba6f57ac1e85e81f2482667c0873fefa4 /arch/powerpc/boot/ns16550.c | |
parent | 6fb4efc68f5c0e095153510dcfa8b54a42e914ba (diff) | |
download | linux-0c176fa80fdfa9b4e0753e37223b056994c818d2.tar.xz |
[POWERPC] Add non-OF serial console support
Add serial console support for non-OF systems. There is a generic serial
console layer which calls a serial console driver. Included is the serial
console driver for the ns16550 class of uarts. Necessary support routines
are added as well.
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/boot/ns16550.c')
-rw-r--r-- | arch/powerpc/boot/ns16550.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/arch/powerpc/boot/ns16550.c b/arch/powerpc/boot/ns16550.c new file mode 100644 index 0000000..1ffe72e --- /dev/null +++ b/arch/powerpc/boot/ns16550.c @@ -0,0 +1,74 @@ +/* + * 16550 serial console support. + * + * Original copied from <file:arch/ppc/boot/common/ns16550.c> + * (which had no copyright) + * Modifications: 2006 (c) MontaVista Software, Inc. + * + * Modified by: Mark A. Greer <mgreer@mvista.com> + */ +#include <stdarg.h> +#include <stddef.h> +#include "types.h" +#include "string.h" +#include "stdio.h" +#include "io.h" +#include "ops.h" + +#define UART_DLL 0 /* Out: Divisor Latch Low */ +#define UART_DLM 1 /* Out: Divisor Latch High */ +#define UART_FCR 2 /* Out: FIFO Control Register */ +#define UART_LCR 3 /* Out: Line Control Register */ +#define UART_MCR 4 /* Out: Modem Control Register */ +#define UART_LSR 5 /* In: Line Status Register */ +#define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */ +#define UART_LSR_DR 0x01 /* Receiver data ready */ +#define UART_MSR 6 /* In: Modem Status Register */ +#define UART_SCR 7 /* I/O: Scratch Register */ + +static unsigned char *reg_base; +static u32 reg_shift; + +static int ns16550_open(void) +{ + out_8(reg_base + (UART_FCR << reg_shift), 0x06); + return 0; +} + +static void ns16550_putc(unsigned char c) +{ + while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_THRE) == 0); + out_8(reg_base, c); +} + +static unsigned char ns16550_getc(void) +{ + while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) == 0); + return in_8(reg_base); +} + +static u8 ns16550_tstc(void) +{ + return ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) != 0); +} + +int ns16550_console_init(void *devp, struct serial_console_data *scdp) +{ + int n; + + n = getprop(devp, "virtual-reg", ®_base, sizeof(reg_base)); + if (n != sizeof(reg_base)) + return -1; + + n = getprop(devp, "reg-shift", ®_shift, sizeof(reg_shift)); + if (n != sizeof(reg_shift)) + reg_shift = 0; + + scdp->open = ns16550_open; + scdp->putc = ns16550_putc; + scdp->getc = ns16550_getc; + scdp->tstc = ns16550_tstc; + scdp->close = NULL; + + return 0; +} |