From 0c176fa80fdfa9b4e0753e37223b056994c818d2 Mon Sep 17 00:00:00 2001 From: "Mark A. Greer" Date: Mon, 16 Oct 2006 13:52:09 -0700 Subject: [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 Signed-off-by: Paul Mackerras --- arch/powerpc/boot/Makefile | 4 +- arch/powerpc/boot/io.h | 53 +++++++++++++++++ arch/powerpc/boot/ns16550.c | 74 +++++++++++++++++++++++ arch/powerpc/boot/serial.c | 142 ++++++++++++++++++++++++++++++++++++++++++++ arch/powerpc/boot/util.S | 88 +++++++++++++++++++++++++++ 5 files changed, 359 insertions(+), 2 deletions(-) create mode 100644 arch/powerpc/boot/io.h create mode 100644 arch/powerpc/boot/ns16550.c create mode 100644 arch/powerpc/boot/serial.c create mode 100644 arch/powerpc/boot/util.S (limited to 'arch/powerpc') diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile index 8660cc50cb1..62435d951db 100644 --- a/arch/powerpc/boot/Makefile +++ b/arch/powerpc/boot/Makefile @@ -40,8 +40,8 @@ zliblinuxheader := zlib.h zconf.h zutil.h $(addprefix $(obj)/,$(zlib) main.o): $(addprefix $(obj)/,$(zliblinuxheader)) \ $(addprefix $(obj)/,$(zlibheader)) -src-wlib := string.S stdio.c main.c flatdevtree.c flatdevtree_misc.c div64.S \ - $(zlib) +src-wlib := string.S stdio.c main.c flatdevtree.c flatdevtree_misc.c \ + ns16550.c serial.c div64.S util.S $(zlib) src-plat := of.c src-boot := crt0.S $(src-wlib) $(src-plat) empty.c diff --git a/arch/powerpc/boot/io.h b/arch/powerpc/boot/io.h new file mode 100644 index 00000000000..32974ed49e0 --- /dev/null +++ b/arch/powerpc/boot/io.h @@ -0,0 +1,53 @@ +#ifndef _IO_H +#define __IO_H +/* + * Low-level I/O routines. + * + * Copied from (which has no copyright) + */ +static inline int in_8(const volatile unsigned char *addr) +{ + int ret; + + __asm__ __volatile__("lbz%U1%X1 %0,%1; twi 0,%0,0; isync" + : "=r" (ret) : "m" (*addr)); + return ret; +} + +static inline void out_8(volatile unsigned char *addr, int val) +{ + __asm__ __volatile__("stb%U0%X0 %1,%0; sync" + : "=m" (*addr) : "r" (val)); +} + +static inline unsigned in_le32(const volatile unsigned *addr) +{ + unsigned ret; + + __asm__ __volatile__("lwbrx %0,0,%1; twi 0,%0,0; isync" + : "=r" (ret) : "r" (addr), "m" (*addr)); + return ret; +} + +static inline unsigned in_be32(const volatile unsigned *addr) +{ + unsigned ret; + + __asm__ __volatile__("lwz%U1%X1 %0,%1; twi 0,%0,0; isync" + : "=r" (ret) : "m" (*addr)); + return ret; +} + +static inline void out_le32(volatile unsigned *addr, int val) +{ + __asm__ __volatile__("stwbrx %1,0,%2; sync" : "=m" (*addr) + : "r" (val), "r" (addr)); +} + +static inline void out_be32(volatile unsigned *addr, int val) +{ + __asm__ __volatile__("stw%U0%X0 %1,%0; sync" + : "=m" (*addr) : "r" (val)); +} + +#endif /* _IO_H */ diff --git a/arch/powerpc/boot/ns16550.c b/arch/powerpc/boot/ns16550.c new file mode 100644 index 00000000000..1ffe72e35cd --- /dev/null +++ b/arch/powerpc/boot/ns16550.c @@ -0,0 +1,74 @@ +/* + * 16550 serial console support. + * + * Original copied from + * (which had no copyright) + * Modifications: 2006 (c) MontaVista Software, Inc. + * + * Modified by: Mark A. Greer + */ +#include +#include +#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; +} diff --git a/arch/powerpc/boot/serial.c b/arch/powerpc/boot/serial.c new file mode 100644 index 00000000000..e8de4cf59be --- /dev/null +++ b/arch/powerpc/boot/serial.c @@ -0,0 +1,142 @@ +/* + * Generic serial console support + * + * Author: Mark A. Greer + * + * Code in serial_edit_cmdline() copied from + * and was written by Matt Porter . + * + * 2001,2006 (c) MontaVista Software, Inc. This file is licensed under + * the terms of the GNU General Public License version 2. This program + * is licensed "as is" without any warranty of any kind, whether express + * or implied. + */ +#include +#include +#include "types.h" +#include "string.h" +#include "stdio.h" +#include "io.h" +#include "ops.h" + +extern void udelay(long delay); + +static int serial_open(void) +{ + struct serial_console_data *scdp = console_ops.data; + return scdp->open(); +} + +static void serial_write(char *buf, int len) +{ + struct serial_console_data *scdp = console_ops.data; + + while (*buf != '\0') + scdp->putc(*buf++); +} + +static void serial_edit_cmdline(char *buf, int len) +{ + int timer = 0, count; + char ch, *cp; + struct serial_console_data *scdp = console_ops.data; + + cp = buf; + count = strlen(buf); + cp = &buf[count]; + count++; + + while (timer++ < 5*1000) { + if (scdp->tstc()) { + while (((ch = scdp->getc()) != '\n') && (ch != '\r')) { + /* Test for backspace/delete */ + if ((ch == '\b') || (ch == '\177')) { + if (cp != buf) { + cp--; + count--; + printf("\b \b"); + } + /* Test for ^x/^u (and wipe the line) */ + } else if ((ch == '\030') || (ch == '\025')) { + while (cp != buf) { + cp--; + count--; + printf("\b \b"); + } + } else if (count < len) { + *cp++ = ch; + count++; + scdp->putc(ch); + } + } + break; /* Exit 'timer' loop */ + } + udelay(1000); /* 1 msec */ + } + *cp = 0; +} + +static void serial_close(void) +{ + struct serial_console_data *scdp = console_ops.data; + + if (scdp->close) + scdp->close(); +} + +static void *serial_get_stdout_devp(void) +{ + void *devp; + char devtype[MAX_PROP_LEN]; + char path[MAX_PATH_LEN]; + + devp = finddevice("/chosen"); + if (devp == NULL) + goto err_out; + + if (getprop(devp, "linux,stdout-path", path, MAX_PATH_LEN) > 0) { + devp = finddevice(path); + if (devp == NULL) + goto err_out; + + if ((getprop(devp, "device_type", devtype, sizeof(devtype)) > 0) + && !strcmp(devtype, "serial")) + return devp; + } +err_out: + return NULL; +} + +static struct serial_console_data serial_cd; + +/* Node's "compatible" property determines which serial driver to use */ +int serial_console_init(void) +{ + void *devp; + int rc = -1; + char compat[MAX_PROP_LEN]; + + devp = serial_get_stdout_devp(); + if (devp == NULL) + goto err_out; + + if (getprop(devp, "compatible", compat, sizeof(compat)) < 0) + goto err_out; + + if (!strcmp(compat, "ns16550")) + rc = ns16550_console_init(devp, &serial_cd); + + /* Add other serial console driver calls here */ + + if (!rc) { + console_ops.open = serial_open; + console_ops.write = serial_write; + console_ops.edit_cmdline = serial_edit_cmdline; + console_ops.close = serial_close; + console_ops.data = &serial_cd; + + return 0; + } +err_out: + return -1; +} diff --git a/arch/powerpc/boot/util.S b/arch/powerpc/boot/util.S new file mode 100644 index 00000000000..427ddfc1199 --- /dev/null +++ b/arch/powerpc/boot/util.S @@ -0,0 +1,88 @@ +/* + * Copied from + * + * This file contains miscellaneous low-level functions. + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Largely rewritten by Cort Dougan (cort@cs.nmt.edu) + * and Paul Mackerras. + * + * kexec bits: + * Copyright (C) 2002-2003 Eric Biederman + * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ +#include "ppc_asm.h" + +#define SPRN_PVR 0x11F /* Processor Version Register */ + + .text + +/* udelay (on non-601 processors) needs to know the period of the + * timebase in nanoseconds. This used to be hardcoded to be 60ns + * (period of 66MHz/4). Now a variable is used that is initialized to + * 60 for backward compatibility, but it can be overridden as necessary + * with code something like this: + * extern unsigned long timebase_period_ns; + * timebase_period_ns = 1000000000 / bd->bi_tbfreq; + */ + .data + .globl timebase_period_ns +timebase_period_ns: + .long 60 + + .text +/* + * Delay for a number of microseconds + */ + .globl udelay +udelay: + mfspr r4,SPRN_PVR + srwi r4,r4,16 + cmpwi 0,r4,1 /* 601 ? */ + bne .udelay_not_601 +00: li r0,86 /* Instructions / microsecond? */ + mtctr r0 +10: addi r0,r0,0 /* NOP */ + bdnz 10b + subic. r3,r3,1 + bne 00b + blr + +.udelay_not_601: + mulli r4,r3,1000 /* nanoseconds */ + /* Change r4 to be the number of ticks using: + * (nanoseconds + (timebase_period_ns - 1 )) / timebase_period_ns + * timebase_period_ns defaults to 60 (16.6MHz) */ + mflr r5 + bl 0f +0: mflr r6 + mtlr r5 + lis r5,0b@ha + addi r5,r5,0b@l + subf r5,r5,r6 /* In case we're relocated */ + addis r5,r5,timebase_period_ns@ha + lwz r5,timebase_period_ns@l(r5) + add r4,r4,r5 + addi r4,r4,-1 + divw r4,r4,r5 /* BUS ticks */ +1: mftbu r5 + mftb r6 + mftbu r7 + cmpw 0,r5,r7 + bne 1b /* Get [synced] base time */ + addc r9,r6,r4 /* Compute end time */ + addze r8,r5 +2: mftbu r5 + cmpw 0,r5,r8 + blt 2b + bgt 3f + mftb r6 + cmpw 0,r6,r9 + blt 2b +3: blr -- cgit v1.2.3-70-g09d2