prep_setup.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

/*
 * BK Id: SCCS/s.prep_setup.c 1.47 12/19/01 09:45:54 trini
 */
/*
 *  linux/arch/ppc/kernel/setup.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 *  Adapted from 'alpha' version by Gary Thomas
 *  Modified by Cort Dougan ([e-mail])
 *
 * Support for PReP (Motorola MTX/MVME)
 * by Troy Benjegerdes ([e-mail])
 */

/*
 * bootup setup stuff..
 */

#include <linux/config.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/tty.h>
#include <linux/major.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/blk.h>
#include <linux/ioport.h>
#include <linux/console.h>
#include <linux/timex.h>
#include <linux/pci.h>
#include <linux/ide.h>
#include <linux/seq_file.h>

#include <asm/sections.h>
#include <asm/mmu.h>
#include <asm/processor.h>
#include <asm/residual.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/cache.h>
#include <asm/dma.h>
#include <asm/machdep.h>
#include <asm/mk48t59.h>
#include <asm/prep_nvram.h>
#include <asm/raven.h>
#include <asm/keyboard.h>
#include <asm/vga.h>
#include <asm/time.h>

#include "local_irq.h"
#include "i8259.h"
#include "open_pic.h"

#if defined(CONFIG_SOUND) || defined(CONFIG_SOUND_MODULE)
#include <../drivers/sound/sound_config.h>
#include <../drivers/sound/dev_table.h>
#endif

unsigned char ucSystemType;
unsigned char ucBoardRev;
unsigned char ucBoardRevMaj, ucBoardRevMin;

extern unsigned long mc146818_get_rtc_time(void);
extern int mc146818_set_rtc_time(unsigned long nowtime);
extern unsigned long mk48t59_get_rtc_time(void);
extern int mk48t59_set_rtc_time(unsigned long nowtime);

extern unsigned char prep_nvram_read_val(int addr);
extern void prep_nvram_write_val(int addr,
				 unsigned char val);
extern unsigned char rs_nvram_read_val(int addr);
extern void rs_nvram_write_val(int addr,
				 unsigned char val);
extern void ibm_prep_init(void);

extern int pckbd_setkeycode(unsigned int scancode, unsigned int keycode);
extern int pckbd_getkeycode(unsigned int scancode);
extern int pckbd_translate(unsigned char scancode, unsigned char *keycode,
		char raw_mode);
extern char pckbd_unexpected_up(unsigned char keycode);
extern void pckbd_leds(unsigned char leds);
extern void pckbd_init_hw(void);
extern unsigned char pckbd_sysrq_xlate[];

extern void prep_find_bridges(void);
extern char saved_command_line[];

int _prep_type;

#define cached_21	(((char *)(ppc_cached_irq_mask))[3])
#define cached_A1	(((char *)(ppc_cached_irq_mask))[2])

/* for the mac fs */
kdev_t boot_dev;
/* used in nasty hack for sound - see prep_setup_arch() -- Cort */
long ppc_cs4232_dma, ppc_cs4232_dma2;

extern PTE *Hash, *Hash_end;
extern unsigned long Hash_size, Hash_mask;
extern int probingmem;
extern unsigned long loops_per_jiffy;

#ifdef CONFIG_BLK_DEV_RAM
extern int rd_doload;		/* 1 = load ramdisk, 0 = don't load */
extern int rd_prompt;		/* 1 = prompt for ramdisk, 0 = don't prompt */
extern int rd_image_start;	/* starting block # of image */
#endif

#ifdef CONFIG_SOUND_MODULE
EXPORT_SYMBOL(ppc_cs4232_dma);
EXPORT_SYMBOL(ppc_cs4232_dma2);
#endif

static int __prep
prep_show_cpuinfo(struct seq_file *m)
{
	extern char *Motherboard_map_name;
	int cachew;
#ifdef CONFIG_PREP_RESIDUAL
	int i;
#endif

	seq_printf(m, "machine\t\t: PReP %s\n", Motherboard_map_name);

	switch ( _prep_type ) {
	case _PREP_IBM:
		cachew = inw(0x80c);
		if (cachew & (1<<6))
			seq_printf(m, "Upgrade CPU\n");
		seq_printf(m, "L2\t\t: ");
		if (cachew & (1<<7)) {
			seq_printf(m, "not present\n");
			goto no_l2;
		}
		seq_printf(m, "%sKb,", (cachew & (1 << 10))? "512" : "256");
		seq_printf(m, "%ssync\n", (cachew & (1 << 15))? "" : "a");
		break;
	case _PREP_Motorola:
		cachew = *((unsigned char *)CACHECRBA);
		seq_printf(m, "L2\t\t: ");
		switch (cachew & L2CACHE_MASK) {
		case L2CACHE_512KB:
			seq_printf(m, "512Kb");
			break;
		case L2CACHE_256KB:
			seq_printf(m, "256Kb");
			break;
		case L2CACHE_1MB:
			seq_printf(m, "1MB");
			break;
		case L2CACHE_NONE:
			seq_printf(m, "none\n");
			goto no_l2;
			break;
		default:
			seq_printf(m, "%x\n", cachew);
		}
		
		seq_printf(m, ", parity %s",
			   (cachew & L2CACHE_PARITY)? "enabled" : "disabled");

		seq_printf(m, " SRAM:");
		
		switch ( ((cachew & 0xf0) >> 4) & ~(0x3) ) {
		case 1: seq_printf(m, "synchronous,parity,flow-through\n");
			break;
		case 2: seq_printf(m, "asynchronous,no parity\n");
			break;
		case 3: seq_printf(m, "asynchronous,parity\n");
			break;
		default:seq_printf(m, "synchronous,pipelined,no parity\n");
			break;
		}
		break;
	default:
		break;
	}

no_l2:
#ifdef CONFIG_PREP_RESIDUAL
	if (res->ResidualLength != 0) {
		/* print info about SIMMs */
		seq_printf(m, "simms\t\t: ");
		for (i = 0; (res->ActualNumMemories) && (i < MAX_MEMS); i++) {
			if (res->Memories[i].SIMMSize != 0)
				seq_printf(m, "%d:%ldM ", i,
					(res->Memories[i].SIMMSize > 1024) ? 
					res->Memories[i].SIMMSize>>20 : 
					res->Memories[i].SIMMSize);
		}
		seq_printf(m, "\n");
	}
#endif

	return 0;
}

static int __prep
prep_show_percpuinfo(struct seq_file *m, int i)
{
	int len = 0;

	/* PREP's without residual data will give incorrect values here */
	seq_printf(m, "clock\t\t: ");
#ifdef CONFIG_PREP_RESIDUAL	
	if (res->ResidualLength)
		seq_printf(m, "%ldMHz\n",
			   (res->VitalProductData.ProcessorHz > 1024) ?
			   res->VitalProductData.ProcessorHz>>20 :
			   res->VitalProductData.ProcessorHz);
	else
#endif /* CONFIG_PREP_RESIDUAL */
		seq_printf(m, "???\n");

	return 0;
}

static void __init
prep_setup_arch(void)
{
	unsigned char reg;
#if 0 /* unused?? */
	unsigned char ucMothMemType;
	unsigned char ucEquipPres1;
#endif

	/* init to some ~sane value until calibrate_delay() runs */
	loops_per_jiffy = 50000000;
	
	/* Lookup PCI host bridges */
	prep_find_bridges();
	
	/* Set up floppy in PS/2 mode */
	outb(0x09, SIO_CONFIG_RA);
	reg = inb(SIO_CONFIG_RD);
	reg = (reg & 0x3F) | 0x40;
	outb(reg, SIO_CONFIG_RD);
	outb(reg, SIO_CONFIG_RD);	/* Have to write twice to change! */

	/*
	 * We need to set up the NvRAM access routines early as prep_init
	 * has yet to be called
	 */
	ppc_md.nvram_read_val = prep_nvram_read_val;
	ppc_md.nvram_write_val = prep_nvram_write_val;

	/* we should determine this according to what we find! -- Cort */
	switch ( _prep_type )
	{
	case _PREP_IBM:
		/* Enable L2.  Assume we don't need to flush -- Cort*/
		*(unsigned char *)(0x8000081c) |= 3;
		ROOT_DEV = to_kdev_t(0x0301); /* hda1 */
		break;
	case _PREP_Motorola:
		/* Enable L2.  Assume we don't need to flush -- Cort*/
		*(unsigned char *)(0x8000081c) |= 3;
#ifdef CONFIG_BLK_DEV_INITRD
		if (initrd_start)
			ROOT_DEV = MKDEV(RAMDISK_MAJOR, 0); /* /dev/ram */
		else
#endif
#ifdef CONFIG_ROOT_NFS
			ROOT_DEV = to_kdev_t(0x00ff); /* /dev/nfs */
#else
			ROOT_DEV = to_kdev_t(0x0802); /* /dev/sda2 */
#endif
		break;
	}

	/* Read in NVRAM data */ 
	init_prep_nvram();

	/* if no bootargs, look in NVRAM */
	if ( cmd_line[0] == '\0' ) {
		char *bootargs;
		 bootargs = prep_nvram_get_var("bootargs");
		 if (bootargs != NULL) {
			 strcpy(cmd_line, bootargs);
			 /* again.. */
			 strcpy(saved_command_line, cmd_line);
		}
	}

#ifdef CONFIG_SOUND_CS4232
	/*
	 * setup proper values for the cs4232 driver so we don't have
	 * to recompile for the motorola or ibm workstations sound systems.
	 * This is a really nasty hack, but unless we change the driver
	 * it's the only way to support both addrs from one binary.
	 * -- Cort
	 */
	if ( _machine == _MACH_prep )
	{
		extern struct card_info snd_installed_cards[];
		struct card_info *snd_ptr;

		for ( snd_ptr = snd_installed_cards; 
			snd_ptr < &snd_installed_cards[num_sound_cards];
			snd_ptr++ )
		{
			if ( snd_ptr->card_type == SNDCARD_CS4232 )
			{
				if ( _prep_type == _PREP_Motorola )
				{
					snd_ptr->config.io_base = 0x830;
					snd_ptr->config.irq = 10;
					snd_ptr->config.dma = ppc_cs4232_dma = 6;
					snd_ptr->config.dma2 = ppc_cs4232_dma2 = 7;
				}
				if ( _prep_type == _PREP_IBM )
				{
					snd_ptr->config.io_base = 0x530;
					snd_ptr->config.irq = 5;
					snd_ptr->config.dma = ppc_cs4232_dma = 1;
					/* this is wrong - but leave it for now */
					snd_ptr->config.dma2 = ppc_cs4232_dma2 = 7;
				}
			}
		}
	}
#endif /* CONFIG_SOUND_CS4232 */	

	/*print_residual_device_info();*/

	switch (_prep_type) {
	case _PREP_Motorola:
		raven_init();
		break;
	case _PREP_IBM:
		ibm_prep_init();
		break;
	}

#ifdef CONFIG_VGA_CONSOLE
	/* remap the VGA memory */
	vgacon_remap_base = 0xf0000000;
	/*vgacon_remap_base = ioremap(0xc0000000, 0xba000);*/
	conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
	conswitchp = &dummy_con;
#endif
}

/*
 * Determine the decrementer frequency from the residual data
 * This allows for a faster boot as we do not need to calibrate the
 * decrementer against another clock. This is important for embedded systems.
 */
static int __init
prep_res_calibrate_decr(void)
{
#ifdef CONFIG_PREP_RESIDUAL
	unsigned long freq, divisor = 4;

	if ( res->VitalProductData.ProcessorBusHz ) {
		freq = res->VitalProductData.ProcessorBusHz;
		printk("time_init: decrementer frequency = %lu.%.6lu MHz\n",
				(freq/divisor)/1000000,
				(freq/divisor)%1000000);
		tb_to_us = mulhwu_scale_factor(freq/divisor, 1000000);
		tb_ticks_per_jiffy = freq / HZ / divisor;
		return 0;
	} else
#endif	
		return 1;
}

/*
 * Uses the on-board timer to calibrate the on-chip decrementer register
 * for prep systems.  On the pmac the OF tells us what the frequency is
 * but on prep we have to figure it out.
 * -- Cort
 */
/* Done with 3 interrupts: the first one primes the cache and the
 * 2 following ones measure the interval. The precision of the method
 * is still doubtful due to the short interval sampled.
 */
static volatile int calibrate_steps __initdata = 3;
static unsigned tbstamp __initdata = 0;

static void __init
prep_calibrate_decr_handler(int irq, void *dev, struct pt_regs *regs)
{
	unsigned long t, freq;
	int step=--calibrate_steps;

	t = get_tbl();
	if (step > 0) {
		tbstamp = t;
	} else {
		freq = (t - tbstamp)*HZ;
		printk("time_init: decrementer frequency = %lu.%.6lu MHz\n",
			 freq/1000000, freq%1000000);
		tb_ticks_per_jiffy = freq / HZ;
		tb_to_us = mulhwu_scale_factor(freq, 1000000);
	}
}

static void __init
prep_calibrate_decr(void)
{
	int res;

	/* Try and get this from the residual data. */
	res = prep_res_calibrate_decr();

	/* If we didn't get it from the residual data, try this. */
	if ( res ) {
		unsigned long flags;

		save_flags(flags);

#define TIMER0_COUNT 0x40
#define TIMER_CONTROL 0x43
		/* set timer to periodic mode */
		outb_p(0x34,TIMER_CONTROL);/* binary, mode 2, LSB/MSB, ch 0 */
		/* set the clock to ~100 Hz */
		outb_p(LATCH & 0xff , TIMER0_COUNT);	/* LSB */
		outb(LATCH >> 8 , TIMER0_COUNT);	/* MSB */

		if (request_irq(0, prep_calibrate_decr_handler, 0, "timer", NULL) != 0)
			panic("Could not allocate timer IRQ!");
		__sti();
		/* wait for calibrate */
		while ( calibrate_steps )
			;
		restore_flags(flags);
		free_irq( 0, NULL);
	}
}

static long __init
mk48t59_init(void) {
	unsigned char tmp;

	tmp = ppc_md.nvram_read_val(MK48T59_RTC_CONTROLB);
	if (tmp & MK48T59_RTC_CB_STOP) {
		printk("Warning: RTC was stopped, date will be wrong.\n");
		ppc_md.nvram_write_val(MK48T59_RTC_CONTROLB, 
					 tmp & ~MK48T59_RTC_CB_STOP);
		/* Low frequency crystal oscillators may take a very long
		 * time to startup and stabilize. For now just ignore the
		 * the issue, but attempting to calibrate the decrementer
		 * from the RTC just after this wakeup is likely to be very 
		 * inaccurate. Firmware should not allow to load
		 * the OS with the clock stopped anyway...
		 */
	}
	/* Ensure that the clock registers are updated */
	tmp = ppc_md.nvram_read_val(MK48T59_RTC_CONTROLA);
	tmp &= ~(MK48T59_RTC_CA_READ | MK48T59_RTC_CA_WRITE);
	ppc_md.nvram_write_val(MK48T59_RTC_CONTROLA, tmp);
	return 0;
}