gemini_setup.c

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/*
 *  linux/arch/ppc/kernel/setup.c
 *
 *  Copyright (C) 1995 Linus Torvalds
 *  Adapted from 'alpha' version by Gary Thomas
 *  Modified by Cort Dougan ([e-mail])
 *  Synergy Microsystems board support by Dan Cox ([e-mail])
 *
 */

#include <linux/config.h>
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/errno.h> 
#include <linux/reboot.h>
#include <linux/pci.h>
#include <linux/time.h>
#include <linux/kdev_t.h>
#include <linux/types.h>
#include <linux/major.h>
#include <linux/blk.h>
#include <linux/console.h>
#include <linux/openpic.h>

#include <asm/system.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <asm/m48t35.h>
#include <asm/gemini.h>

#include <asm/time.h>
#include "local_irq.h"
#include "open_pic.h"

void gemini_setup_pci_ptrs(void);
static int gemini_get_clock_speed(void);
extern void gemini_pcibios_fixup(void);

static char *gemini_board_families[] = {
  "VGM", "VSS", "KGM", "VGR", "VCM", "VCS", "KCM", "VCR"
};
static int gemini_board_count = sizeof(gemini_board_families) /
                                 sizeof(gemini_board_families[0]);

static unsigned int cpu_7xx[16] = {
	0, 15, 14, 0, 0, 13, 5, 9, 6, 11, 8, 10, 16, 12, 7, 0
};
static unsigned int cpu_6xx[16] = {
	0, 0, 14, 0, 0, 13, 5, 9, 6, 11, 8, 10, 0, 12, 7, 0
};

int chrp_get_irq(struct pt_regs *);
void chrp_post_irq(struct pt_regs* regs, int);

static inline unsigned long _get_HID1(void)
{
	unsigned long val;

	__asm__ __volatile__("mfspr %0,1009" : "=r" (val));
	return val;
}

int
gemini_get_cpuinfo(char *buffer)
{
	int len;
	unsigned char reg, rev;
	char *family;
	unsigned int type;

	reg = readb(GEMINI_FEAT);
	family = gemini_board_families[((reg>>4) & 0xf)];
	if (((reg>>4) & 0xf) > gemini_board_count)
		printk(KERN_ERR "cpuinfo(): unable to determine board family\n");

	reg = readb(GEMINI_BREV);
	type = (reg>>4) & 0xf;
	rev = reg & 0xf;

	reg = readb(GEMINI_BECO);

	len = sprintf( buffer, "machine\t\t: Gemini %s%d, rev %c, eco %d\n", 
		       family, type, (rev + 'A'), (reg & 0xf));

	len = sprintf(buffer, "board\t\t: Gemini %s", family);
	if (type > 9)
		len += sprintf(buffer+len, "%c", (type - 10) + 'A');
	else
		len += sprintf(buffer+len, "%d", type);

	len += sprintf(buffer+len, ", rev %c, eco %d\n",
		       (rev + 'A'), (reg & 0xf));

	len += sprintf(buffer+len, "clock\t\t: %dMhz\n", 
		       gemini_get_clock_speed());

	return len;
}

static u_char gemini_openpic_initsenses[] = {
	1,
	1,
	1,
	1,
	0,
	0,
	1, /* remainder are level-triggered */
};

#define GEMINI_MPIC_ADDR (0xfcfc0000)
#define GEMINI_MPIC_PCI_CFG (0x80005800)

void __init gemini_openpic_init(void)
{

	OpenPIC = (volatile struct OpenPIC *)
		grackle_read(0x80005800 + 0x10);
#if 0	
	grackle_write(GEMINI_MPIC_PCI_CFG + PCI_BASE_ADDRESS_0, 
		      GEMINI_MPIC_ADDR);
	grackle_write(GEMINI_MPIC_PCI_CFG + PCI_COMMAND, PCI_COMMAND_MEMORY);

	OpenPIC = (volatile struct OpenPIC *) GEMINI_MPIC_ADDR;
#endif
	OpenPIC_InitSenses = gemini_openpic_initsenses;
	OpenPIC_NumInitSenses = sizeof( gemini_openpic_initsenses );

	ioremap( GEMINI_MPIC_ADDR, sizeof( struct OpenPIC ));
}


extern unsigned long loops_per_sec;
extern int root_mountflags;
extern char cmd_line[];

void
gemini_heartbeat(void)
{
	static unsigned long led = GEMINI_LEDBASE+(4*8);
	static char direction = 8;
	*(char *)led = 0;
	if ( (led + direction) > (GEMINI_LEDBASE+(7*8)) ||
	     (led + direction) < (GEMINI_LEDBASE+(4*8)) )
		direction *= -1;
	led += direction;
	*(char *)led = 0xff;
	ppc_md.heartbeat_count = ppc_md.heartbeat_reset;
}

void __init gemini_setup_arch(void)
{
	extern char cmd_line[];


	loops_per_sec = 50000000;

#ifdef CONFIG_BLK_DEV_INITRD
	/* bootable off CDROM */
	if (initrd_start)
		ROOT_DEV = MKDEV(SCSI_CDROM_MAJOR, 0);
	else
#endif
		ROOT_DEV = to_kdev_t(0x0801);

	/* nothing but serial consoles... */  
	sprintf(cmd_line, "%s console=ttyS0", cmd_line);

	printk("Boot arguments: %s\n", cmd_line);

	ppc_md.heartbeat = gemini_heartbeat;
	ppc_md.heartbeat_reset = HZ/8;
	ppc_md.heartbeat_count = 1;
	
	/* take special pains to map the MPIC, since it isn't mapped yet */
	gemini_openpic_init();
	/* start the L2 */
	gemini_init_l2();
}


int
gemini_get_clock_speed(void)
{
	unsigned long hid1, pvr = _get_PVR();
	int clock;

	hid1 = (_get_HID1() >> 28) & 0xf;
	if (PVR_VER(pvr) == 8 ||
	    PVR_VER(pvr) == 12)
		hid1 = cpu_7xx[hid1];
	else
		hid1 = cpu_6xx[hid1];

	switch((readb(GEMINI_BSTAT) & 0xc) >> 2) {

	case 0:
	default:
		clock = (hid1*100)/3;
		break;
  
	case 1:
		clock = (hid1*125)/3;
		break;
  
	case 2:
		clock = (hid1*50);
		break;
	}

	return clock;
}

#define L2CR_PIPE_LATEWR   (0x01800000)   /* late-write SRAM */
#define L2CR_L2CTL         (0x00100000)   /* RAM control */
#define L2CR_INST_DISABLE  (0x00400000)   /* disable for insn's */
#define L2CR_L2I           (0x00200000)   /* global invalidate */
#define L2CR_L2E           (0x80000000)   /* enable */
#define L2CR_L2WT          (0x00080000)   /* write-through */

void __init gemini_init_l2(void)
{
        unsigned char reg, brev, fam, creg;
        unsigned long cache;
        unsigned long pvr = _get_PVR();

        reg = readb(GEMINI_L2CFG);
        brev = readb(GEMINI_BREV);
        fam = readb(GEMINI_FEAT);

        switch(PVR_VER(pvr)) {

        case 8:
                if (reg & 0xc0)
                        cache = (((reg >> 6) & 0x3) << 28);
                else
                        cache = 0x3 << 28;

#ifdef CONFIG_SMP
                /* Pre-3.0 processor revs had snooping errata.  Leave
                   their L2's disabled with SMP. -- Dan */
                if (PVR_CFG(pvr) < 3) {
                        printk("Pre-3.0 750; L2 left disabled!\n");
                        return;
                }
#endif /* CONFIG_SMP */

                /* Special case: VGM5-B's came before L2 ratios were set on
                   the board.  Processor speed shouldn't be too high, so
                   set L2 ratio to 1:1.5.  */
                if ((brev == 0x51) && ((fam & 0xa0) >> 4) == 0)
                        reg |= 1;

                /* determine best cache ratio based upon what the board
                   tells us (which sometimes _may_ not be true) and
                   the processor speed. */
                else {
                        if (gemini_get_clock_speed() > 250)
                                reg = 2;
                }
                break;
        case 12:
	{
		static unsigned long l2_size_val = 0;
		
		if (!l2_size_val)
			l2_size_val = _get_L2CR();
		cache = l2_size_val;
                break;
	}
        case 4:
        case 9:
                creg = readb(GEMINI_CPUSTAT);
                if (((creg & 0xc) >> 2) != 1)
                        printk("Dual-604 boards don't support the use of L2\n");
                else
                        writeb(1, GEMINI_L2CFG);
                return;
        default:
                printk("Unknown processor; L2 left disabled\n");
                return;
        }

        cache |= ((1<<reg) << 25);
        cache |= (L2CR_PIPE_LATEWR|L2CR_L2CTL|L2CR_INST_DISABLE);
        _set_L2CR(0);
        _set_L2CR(cache | L2CR_L2I | L2CR_L2E);

}

void
gemini_restart(char *cmd)
{
	__cli();
	/* make a clean restart, not via the MPIC */
	_gemini_reboot();
	for(;;);
}

void
gemini_power_off(void)
{
	for(;;);
}

void
gemini_halt(void)
{
	gemini_restart(NULL);
}

void __init gemini_init_IRQ(void)
{
	int i;

	/* gemini has no 8259 */
	open_pic_irq_offset = 0;
	for( i=0; i < NR_IRQS; i++ ) 
		irq_desc[i].handler = &open_pic;
	openpic_init(1);
#ifdef CONFIG_SMP
 	request_irq(OPENPIC_VEC_IPI, openpic_ipi_action,
 		    0, "IPI0", 0);
 	request_irq(OPENPIC_VEC_IPI+1, openpic_ipi_action,
 		    0, "IPI1 (invalidate TLB)", 0);
 	request_irq(OPENPIC_VEC_IPI+2, openpic_ipi_action,
 		    0, "IPI2 (stop CPU)", 0);
 	request_irq(OPENPIC_VEC_IPI+3, openpic_ipi_action,
 		    0, "IPI3 (reschedule)", 0);
#endif	/* CONFIG_SMP */
}

#define gemini_rtc_read(x)       (readb(GEMINI_RTC+(x)))
#define gemini_rtc_write(val,x)  (writeb((val),(GEMINI_RTC+(x))))

/* ensure that the RTC is up and running */
long __init gemini_time_init(void)
{
	unsigned char reg;

	reg = gemini_rtc_read(M48T35_RTC_CONTROL);

	if ( reg & M48T35_RTC_STOPPED ) {
		printk(KERN_INFO "M48T35 real-time-clock was stopped. Now starting...\n");
		gemini_rtc_write((reg & ~(M48T35_RTC_STOPPED)), M48T35_RTC_CONTROL);
		gemini_rtc_write((reg | M48T35_RTC_SET), M48T35_RTC_CONTROL);
	}
	return 0;
}

#undef DEBUG_RTC

unsigned long
gemini_get_rtc_time(void)
{
	unsigned int year, mon, day, hour, min, sec;
	unsigned char reg;

	reg = gemini_rtc_read(M48T35_RTC_CONTROL);
	gemini_rtc_write((reg|M48T35_RTC_READ), M48T35_RTC_CONTROL);
#ifdef DEBUG_RTC
	printk("get rtc: reg = %x\n", reg);
#endif
  
	do {
		sec = gemini_rtc_read(M48T35_RTC_SECONDS);
		min = gemini_rtc_read(M48T35_RTC_MINUTES);
		hour = gemini_rtc_read(M48T35_RTC_HOURS);
		day = gemini_rtc_read(M48T35_RTC_DOM);
		mon = gemini_rtc_read(M48T35_RTC_MONTH);
		year = gemini_rtc_read(M48T35_RTC_YEAR);
	} while( sec != gemini_rtc_read(M48T35_RTC_SECONDS));
#ifdef DEBUG_RTC
	printk("get rtc: sec=%x, min=%x, hour=%x, day=%x, mon=%x, year=%x\n", 
	       sec, min, hour, day, mon, year);
#endif

	gemini_rtc_write(reg, M48T35_RTC_CONTROL);

	BCD_TO_BIN(sec);
	BCD_TO_BIN(min);
	BCD_TO_BIN(hour);
	BCD_TO_BIN(day);
	BCD_TO_BIN(mon);
	BCD_TO_BIN(year);

	if ((year += 1900) < 1970)
		year += 100;
#ifdef DEBUG_RTC
	printk("get rtc: sec=%x, min=%x, hour=%x, day=%x, mon=%x, year=%x\n", 
	       sec, min, hour, day, mon, year);
#endif

	return mktime( year, mon, day, hour, min, sec );
}


int
gemini_set_rtc_time( unsigned long now )
{
	unsigned char reg;
	struct rtc_time tm;

	to_tm( now, &tm );

	reg = gemini_rtc_read(M48T35_RTC_CONTROL);
#if DEBUG_RTC
	printk("set rtc: reg = %x\n", reg);
#endif
  
	gemini_rtc_write((reg|M48T35_RTC_SET), M48T35_RTC_CONTROL);
#if DEBUG_RTC
	printk("set rtc: tm vals - sec=%x, min=%x, hour=%x, mon=%x, mday=%x, year=%x\n",
	       tm.tm_sec, tm.tm_min, tm.tm_hour, tm.tm_mon, tm.tm_mday, tm.tm_year);
#endif
  
	tm.tm_year -= 1900;
	BIN_TO_BCD(tm.tm_sec);
	BIN_TO_BCD(tm.tm_min);
	BIN_TO_BCD(tm.tm_hour);
	BIN_TO_BCD(tm.tm_mon);
	BIN_TO_BCD(tm.tm_mday);
	BIN_TO_BCD(tm.tm_year);
#ifdef DEBUG_RTC
	printk("set rtc: tm vals - sec=%x, min=%x, hour=%x, mon=%x, mday=%x, year=%x\n",
	       tm.tm_sec, tm.tm_min, tm.tm_hour, tm.tm_mon, tm.tm_mday, tm.tm_year);
#endif

	gemini_rtc_write(tm.tm_sec, M48T35_RTC_SECONDS);
	gemini_rtc_write(tm.tm_min, M48T35_RTC_MINUTES);
	gemini_rtc_write(tm.tm_hour, M48T35_RTC_HOURS);
	gemini_rtc_write(tm.tm_mday, M48T35_RTC_DOM);
	gemini_rtc_write(tm.tm_mon, M48T35_RTC_MONTH);
	gemini_rtc_write(tm.tm_year, M48T35_RTC_YEAR);

	/* done writing */
	gemini_rtc_write(reg, M48T35_RTC_CONTROL);

	if ((time_state == TIME_ERROR) || (time_state == TIME_BAD))
		time_state = TIME_OK;
  
	return 0;
}

/*  use the RTC to determine the decrementer count */
void __init gemini_calibrate_decr(void)
{
	int freq, divisor;
	unsigned char reg;

	/* determine processor bus speed */
	reg = readb(GEMINI_BSTAT);

	switch(((reg & 0x0c)>>2)&0x3) {
	case 0:
	default:
		freq = 66;
		break;
	case 1:
		freq = 83;
		break;
	case 2:
		freq = 100;
		break;
	}

	freq *= 1000000;
	divisor = 4;
	decrementer_count = freq / HZ / divisor;
	count_period_num = divisor;
	count_period_den = freq / 1000000;
}

int gemini_get_irq( struct pt_regs *regs )
{
        int irq;

        irq = openpic_irq( smp_processor_id() );
        if (irq == OPENPIC_VEC_SPURIOUS)
                /*
                 * Spurious interrupts should never be
                 * acknowledged
                 */
		irq = -1;
	/*
	 * I would like to openpic_eoi here but there seem to be timing problems
	 * between the openpic ack and the openpic eoi.
	 *   -- Cort
	 */
	return irq;
}

void gemini_post_irq(struct pt_regs* regs, int irq)
{
	/*
	 * If it's an i8259 irq then we've already done the
	 * openpic irq.  So we just check to make sure the controller
	 * is an openpic and if it is then eoi
	 *
	 * We do it this way since our irq_desc[irq].handler can change
	 * with RTL and no longer be open_pic -- Cort
	 */
	if ( irq >= open_pic_irq_offset)
		openpic_eoi( smp_processor_id() );
}


void __init gemini_init(unsigned long r3, unsigned long r4, unsigned long r5,
			unsigned long r6, unsigned long r7)
{
	int i;
	int chrp_get_irq( struct pt_regs * );

	for(i = 0; i < GEMINI_LEDS; i++)
		gemini_led_off(i);
 
	gemini_setup_pci_ptrs();

	ISA_DMA_THRESHOLD = 0;
	DMA_MODE_READ = 0;
	DMA_MODE_WRITE = 0;

#ifdef CONFIG_BLK_DEV_INITRD
	if ( r4 )
	{
		initrd_start = r4 + KERNELBASE;
		initrd_end = r5 + KERNELBASE;
	}
#endif

	ppc_md.setup_arch = gemini_setup_arch;
	ppc_md.setup_residual = NULL;
	ppc_md.get_cpuinfo = gemini_get_cpuinfo;
	ppc_md.irq_cannonicalize = NULL;
	ppc_md.init_IRQ = gemini_init_IRQ;
	ppc_md.get_irq = gemini_get_irq;
	ppc_md.post_irq = gemini_post_irq;
	ppc_md.init = NULL;

	ppc_md.restart = gemini_restart;
	ppc_md.power_off = gemini_power_off;
	ppc_md.halt = gemini_halt;

	ppc_md.time_init = gemini_time_init;
	ppc_md.set_rtc_time = gemini_set_rtc_time;
	ppc_md.get_rtc_time = gemini_get_rtc_time;
	ppc_md.calibrate_decr = gemini_calibrate_decr;

	/* no keyboard/mouse/video stuff yet.. */
	ppc_md.kbd_setkeycode = NULL;
	ppc_md.kbd_getkeycode = NULL;
	ppc_md.kbd_translate = NULL;
	ppc_md.kbd_unexpected_up = NULL;
	ppc_md.kbd_leds = NULL;
	ppc_md.kbd_init_hw = NULL;
#ifdef CONFIG_MAGIC_SYSRQ
	ppc_md.ppc_kbd_sysrq_xlate = NULL;
#endif
	ppc_md.pcibios_fixup_bus = gemini_pcibios_fixup;
}