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Commit e76fe574 authored by Magnus Damm's avatar Magnus Damm Committed by Paul Mundt
Browse files

sh: Remove old early serial console code V2 



Now when the sh-sci driver can do early serial output,
get rid of the old duplicated code. This patch is V2 and
removes support for "earlyprintk=serial" together with
the following kconfig options:
CONFIG_EARLY_SCIF_CONSOLE
CONFIG_EARLY_SCIF_CONSOLE_PORT
CONFIG_EARLY_PRINTK

With this patch applied "earlyprintk=" support is always
built-in the SuperH kernel. For this to work the serial
driver must have early platform support and in the case
of sh-sci the serial console needs to be enabled:
CONFIG_SERIAL_SH_SCI_CONSOLE=y

So after enabling the SuperH SCI console kconfig option
you also need to point out port using the kernel command
line: "earlyprintk=sh-sci.N[,baudrate][,keep]"

Remember that clocks may be disabled by the boot loader
so you may have to do some board specific static clock
setup before earlyprintk will work on your platform.

Signed-off-by: default avatarMagnus Damm <damm@opensource.se>
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent d8d3fbb0

arch/sh/Kconfig.debug

+0 −44
Original line number Diff line number Diff line
@@ -19,50 +19,6 @@ config SH_STANDARD_BIOS 
	  mask ROM and no flash (WindowsCE machines fall in this category).

	  If unsure, say N.



config EARLY_SCIF_CONSOLE

	bool "Use early SCIF console"

	help

	  This enables an early console using a fixed SCIF port. This can

	  be used by platforms that are either not running the SH

	  standard BIOS, or do not wish to use the BIOS callbacks for the

	  serial I/O.



config EARLY_SCIF_CONSOLE_PORT

	hex

	depends on EARLY_SCIF_CONSOLE

	default "0xa4400000" if CPU_SUBTYPE_SH7712 || CPU_SUBTYPE_SH7705

	default "0xa4430000" if CPU_SUBTYPE_SH7720 || CPU_SUBTYPE_SH7721

	default "0xf8420000" if CPU_SUBTYPE_SH7619

	default "0xff804000" if CPU_SUBTYPE_MXG

	default "0xffc30000" if CPU_SUBTYPE_SHX3

	default "0xffe00000" if CPU_SUBTYPE_SH7780 || CPU_SUBTYPE_SH7763 || \

				CPU_SUBTYPE_SH7722 || CPU_SUBTYPE_SH7366 || \

				CPU_SUBTYPE_SH7343

	default "0xfe4c0000" if CPU_SUBTYPE_SH7757

	default "0xffeb0000" if CPU_SUBTYPE_SH7785

	default "0xffeb0000" if CPU_SUBTYPE_SH7786

	default "0xfffe8000" if CPU_SUBTYPE_SH7203

	default "0xfffe9800" if CPU_SUBTYPE_SH7206 || CPU_SUBTYPE_SH7263

	default "0xffe80000" if CPU_SH4

	default "0xa4000150" if CPU_SH3

	default "0x00000000"



config EARLY_PRINTK

	bool "Early printk support"

	depends on SH_STANDARD_BIOS || EARLY_SCIF_CONSOLE

	help

	  Say Y here to redirect kernel printk messages to the serial port

	  used by the SH-IPL bootloader, starting very early in the boot

	  process and ending when the kernel's serial console is initialised.

	  This option is only useful porting the kernel to a new machine,

	  when the kernel may crash or hang before the serial console is

	  initialised. If unsure, say N.



	  On devices that are running SH-IPL and want to keep the port

	  initialization consistent while not using the BIOS callbacks,

	  select both the EARLY_SCIF_CONSOLE and SH_STANDARD_BIOS, using

	  the kernel command line option to toggle back and forth.



config STACK_DEBUG

	bool "Check for stack overflows"

	depends on DEBUG_KERNEL && SUPERH32

arch/sh/kernel/Makefile

+1 −2
Original line number Diff line number Diff line
@@ -22,11 +22,10 @@ obj-y := debugtraps.o dma-nommu.o dumpstack.o \ 
obj-y				+= cpu/

obj-$(CONFIG_VSYSCALL)		+= vsyscall/

obj-$(CONFIG_SMP)		+= smp.o

obj-$(CONFIG_SH_STANDARD_BIOS)	+= sh_bios.o

obj-$(CONFIG_SH_STANDARD_BIOS)	+= sh_bios.o early_printk.o

obj-$(CONFIG_KGDB)		+= kgdb.o

obj-$(CONFIG_SH_CPU_FREQ)	+= cpufreq.o

obj-$(CONFIG_MODULES)		+= sh_ksyms_$(BITS).o module.o

obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o

obj-$(CONFIG_KEXEC)		+= machine_kexec.o relocate_kernel.o

obj-$(CONFIG_CRASH_DUMP)	+= crash_dump.o

obj-$(CONFIG_STACKTRACE)	+= stacktrace.o

arch/sh/kernel/early_printk.c

+0 −147
Original line number Diff line number Diff line
@@ -15,7 +15,6 @@ 
#include <linux/io.h>

#include <linux/delay.h>



#ifdef CONFIG_SH_STANDARD_BIOS

#include <asm/sh_bios.h>



/*
@@ -57,140 +56,7 @@ static struct console bios_console = { 
	.flags		= CON_PRINTBUFFER,

	.index		= -1,

};

#endif



#ifdef CONFIG_EARLY_SCIF_CONSOLE

#include <linux/serial_core.h>

#include "../../../drivers/serial/sh-sci.h"



#if defined(CONFIG_CPU_SUBTYPE_SH7720) || \

    defined(CONFIG_CPU_SUBTYPE_SH7721)

#define EPK_SCSMR_VALUE 0x000

#define EPK_SCBRR_VALUE 0x00C

#define EPK_FIFO_SIZE 64

#define EPK_FIFO_BITS (0x7f00 >> 8)

#else

#define EPK_FIFO_SIZE 16

#define EPK_FIFO_BITS (0x1f00 >> 8)

#endif



static struct uart_port scif_port = {

	.type		= PORT_SCIF,

	.mapbase	= CONFIG_EARLY_SCIF_CONSOLE_PORT,

	.membase	= (char __iomem *)CONFIG_EARLY_SCIF_CONSOLE_PORT,

};



static void scif_sercon_putc(int c)

{

	while (((sci_in(&scif_port, SCFDR) & EPK_FIFO_BITS) >= EPK_FIFO_SIZE))

		;



	sci_in(&scif_port, SCxSR);

	sci_out(&scif_port, SCxSR, 0xf3 & ~(0x20 | 0x40));

	sci_out(&scif_port, SCxTDR, c);



	while ((sci_in(&scif_port, SCxSR) & 0x40) == 0)

		;



	if (c == '\n')

		scif_sercon_putc('\r');

}



static void scif_sercon_write(struct console *con, const char *s,

			      unsigned count)

{

	while (count-- > 0)

		scif_sercon_putc(*s++);

}



static int __init scif_sercon_setup(struct console *con, char *options)

{

	con->cflag = CREAD | HUPCL | CLOCAL | B115200 | CS8;



	return 0;

}



static struct console scif_console = {

	.name		= "sercon",

	.write		= scif_sercon_write,

	.setup		= scif_sercon_setup,

	.flags		= CON_PRINTBUFFER,

	.index		= -1,

};



#if !defined(CONFIG_SH_STANDARD_BIOS)

#if defined(CONFIG_CPU_SUBTYPE_SH7720) || \

    defined(CONFIG_CPU_SUBTYPE_SH7721)

static void scif_sercon_init(char *s)

{

	sci_out(&scif_port, SCSCR, 0x0000);	/* clear TE and RE */

	sci_out(&scif_port, SCFCR, 0x4006);	/* reset */

	sci_out(&scif_port, SCSCR, 0x0000);	/* select internal clock */

	sci_out(&scif_port, SCSMR, EPK_SCSMR_VALUE);

	sci_out(&scif_port, SCBRR, EPK_SCBRR_VALUE);



	mdelay(1);	/* wait 1-bit time */



	sci_out(&scif_port, SCFCR, 0x0030);	/* TTRG=b'11 */

	sci_out(&scif_port, SCSCR, 0x0030);	/* TE, RE */

}

#elif defined(CONFIG_CPU_SH4) || defined(CONFIG_CPU_SH3)

#define DEFAULT_BAUD 115200

/*

 * Simple SCIF init, primarily aimed at SH7750 and other similar SH-4

 * devices that aren't using sh-ipl+g.

 */

static void scif_sercon_init(char *s)

{

	struct uart_port *port = &scif_port;

	unsigned baud = DEFAULT_BAUD;

	unsigned int status;

	char *e;



	if (*s == ',')

		++s;



	if (*s) {

		/* ignore ioport/device name */

		s += strcspn(s, ",");

		if (*s == ',')

			s++;

	}



	if (*s) {

		baud = simple_strtoul(s, &e, 0);

		if (baud == 0 || s == e)

			baud = DEFAULT_BAUD;

	}



	do {

		status = sci_in(port, SCxSR);

	} while (!(status & SCxSR_TEND(port)));



	sci_out(port, SCSCR, 0);	 /* TE=0, RE=0 */

	sci_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);

	sci_out(port, SCSMR, 0);



	/* Set baud rate */

	sci_out(port, SCBRR, (CONFIG_SH_PCLK_FREQ + 16 * baud) /

		(32 * baud) - 1);

	udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */



	sci_out(port, SCSPTR, 0);

	sci_out(port, SCxSR, 0x60);

	sci_out(port, SCLSR, 0);



	sci_out(port, SCFCR, 0);

	sci_out(port, SCSCR, 0x30);	 /* TE=1, RE=1 */

}

#endif /* defined(CONFIG_CPU_SUBTYPE_SH7720) */

#endif /* !defined(CONFIG_SH_STANDARD_BIOS) */

#endif /* CONFIG_EARLY_SCIF_CONSOLE */



/*

 * Setup a default console, if more than one is compiled in, rely on the

 * earlyprintk= parsing to give priority.

 */

static struct console *early_console;



static int __init setup_early_printk(char *buf)
@@ -203,21 +69,8 @@ static int __init setup_early_printk(char *buf) 
	if (strstr(buf, "keep"))

		keep_early = 1;



#ifdef CONFIG_SH_STANDARD_BIOS

	if (!strncmp(buf, "bios", 4))

		early_console = &bios_console;

#endif

#if defined(CONFIG_EARLY_SCIF_CONSOLE)

	if (!strncmp(buf, "serial", 6)) {

		early_console = &scif_console;



#if !defined(CONFIG_SH_STANDARD_BIOS)

#if defined(CONFIG_CPU_SH4) || defined(CONFIG_CPU_SH3)

		scif_sercon_init(buf + 6);

#endif

#endif

	}

#endif



	if (likely(early_console)) {

		if (keep_early)