voyager_cat.c

linux 内核源代码

/* -*- mode: c; c-basic-offset: 8 -*- */

/* Copyright (C) 1999,2001
 *
 * Author: [e-mail]
 *
 * linux/arch/i386/kernel/voyager_cat.c
 *
 * This file contains all the logic for manipulating the CAT bus
 * in a level 5 machine.
 *
 * The CAT bus is a serial configuration and test bus.  Its primary
 * uses are to probe the initial configuration of the system and to
 * diagnose error conditions when a system interrupt occurs.  The low
 * level interface is fairly primitive, so most of this file consists
 * of bit shift manipulations to send and receive packets on the
 * serial bus */

#include <linux/types.h>
#include <linux/completion.h>
#include <linux/sched.h>
#include <asm/voyager.h>
#include <asm/vic.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <asm/io.h>

#ifdef VOYAGER_CAT_DEBUG
#define CDEBUG(x)	printk x
#else
#define CDEBUG(x)
#endif

/* the CAT command port */
#define CAT_CMD		(sspb + 0xe)
/* the CAT data port */
#define CAT_DATA	(sspb + 0xd)

/* the internal cat functions */
static void cat_pack(__u8 *msg, __u16 start_bit, __u8 *data, 
		     __u16 num_bits);
static void cat_unpack(__u8 *msg, __u16 start_bit, __u8 *data,
		       __u16 num_bits);
static void cat_build_header(__u8 *header, const __u16 len, 
			     const __u16 smallest_reg_bits,
			     const __u16 longest_reg_bits);
static int cat_sendinst(voyager_module_t *modp, voyager_asic_t *asicp,
			__u8 reg, __u8 op);
static int cat_getdata(voyager_module_t *modp, voyager_asic_t *asicp,
		       __u8 reg, __u8 *value);
static int cat_shiftout(__u8 *data, __u16 data_bytes, __u16 header_bytes,
			__u8 pad_bits);
static int cat_write(voyager_module_t *modp, voyager_asic_t *asicp, __u8 reg,
		     __u8 value);
static int cat_read(voyager_module_t *modp, voyager_asic_t *asicp, __u8 reg,
		    __u8 *value);
static int cat_subread(voyager_module_t *modp, voyager_asic_t *asicp,
		       __u16 offset, __u16 len, void *buf);
static int cat_senddata(voyager_module_t *modp, voyager_asic_t *asicp,
			__u8 reg, __u8 value);
static int cat_disconnect(voyager_module_t *modp, voyager_asic_t *asicp);
static int cat_connect(voyager_module_t *modp, voyager_asic_t *asicp);

static inline const char *
cat_module_name(int module_id)
{
	switch(module_id) {
	case 0x10:
		return "Processor Slot 0";
	case 0x11:
		return "Processor Slot 1";
	case 0x12:
		return "Processor Slot 2";
	case 0x13:
		return "Processor Slot 4";
	case 0x14:
		return "Memory Slot 0";
	case 0x15:
		return "Memory Slot 1";
	case 0x18:
		return "Primary Microchannel";
	case 0x19:
		return "Secondary Microchannel";
	case 0x1a:
		return "Power Supply Interface";
	case 0x1c:
		return "Processor Slot 5";
	case 0x1d:
		return "Processor Slot 6";
	case 0x1e:
		return "Processor Slot 7";
	case 0x1f:
		return "Processor Slot 8";
	default:
		return "Unknown Module";
	}
}

static int sspb = 0;		/* stores the super port location */
int voyager_8slot = 0;		/* set to true if a 51xx monster */

voyager_module_t *voyager_cat_list;

/* the I/O port assignments for the VIC and QIC */
static struct resource vic_res = {
	.name	= "Voyager Interrupt Controller",
	.start	= 0xFC00,
	.end	= 0xFC6F
};
static struct resource qic_res = {
	.name	= "Quad Interrupt Controller",
	.start	= 0xFC70,
	.end	= 0xFCFF
};

/* This function is used to pack a data bit stream inside a message.
 * It writes num_bits of the data buffer in msg starting at start_bit.
 * Note: This function assumes that any unused bit in the data stream
 * is set to zero so that the ors will work correctly */
static void
cat_pack(__u8 *msg, const __u16 start_bit, __u8 *data, const __u16 num_bits)
{
	/* compute initial shift needed */
	const __u16 offset = start_bit % BITS_PER_BYTE;
	__u16 len = num_bits / BITS_PER_BYTE;
	__u16 byte = start_bit / BITS_PER_BYTE;
	__u16 residue = (num_bits % BITS_PER_BYTE) + offset;
	int i;

	/* adjust if we have more than a byte of residue */
	if(residue >= BITS_PER_BYTE) {
		residue -= BITS_PER_BYTE;
		len++;
	}

	/* clear out the bits.  We assume here that if len==0 then
	 * residue >= offset.  This is always true for the catbus
	 * operations */
	msg[byte] &= 0xff << (BITS_PER_BYTE - offset); 
	msg[byte++] |= data[0] >> offset;
	if(len == 0)
		return;
	for(i = 1; i < len; i++)
		msg[byte++] = (data[i-1] << (BITS_PER_BYTE - offset))
			| (data[i] >> offset);
	if(residue != 0) {
		__u8 mask = 0xff >> residue;
		__u8 last_byte = data[i-1] << (BITS_PER_BYTE - offset)
			| (data[i] >> offset);
		
		last_byte &= ~mask;
		msg[byte] &= mask;
		msg[byte] |= last_byte;
	}
	return;
}
/* unpack the data again (same arguments as cat_pack()). data buffer
 * must be zero populated.
 *
 * Function: given a message string move to start_bit and copy num_bits into
 * data (starting at bit 0 in data).
 */
static void
cat_unpack(__u8 *msg, const __u16 start_bit, __u8 *data, const __u16 num_bits)
{
	/* compute initial shift needed */
	const __u16 offset = start_bit % BITS_PER_BYTE;
	__u16 len = num_bits / BITS_PER_BYTE;
	const __u8 last_bits = num_bits % BITS_PER_BYTE;
	__u16 byte = start_bit / BITS_PER_BYTE;
	int i;

	if(last_bits != 0)
		len++;

	/* special case: want < 8 bits from msg and we can get it from
	 * a single byte of the msg */
	if(len == 0 && BITS_PER_BYTE - offset >= num_bits) {
		data[0] = msg[byte] << offset;
		data[0] &= 0xff >> (BITS_PER_BYTE - num_bits);
		return;
	}
	for(i = 0; i < len; i++) {
		/* this annoying if has to be done just in case a read of
		 * msg one beyond the array causes a panic */
		if(offset != 0) {
			data[i] = msg[byte++] << offset;
			data[i] |= msg[byte] >> (BITS_PER_BYTE - offset);
		}
		else {
			data[i] = msg[byte++];
		}
	}
	/* do we need to truncate the final byte */
	if(last_bits != 0) {
		data[i-1] &= 0xff << (BITS_PER_BYTE - last_bits);
	}
	return;
}

static void
cat_build_header(__u8 *header, const __u16 len, const __u16 smallest_reg_bits,
		 const __u16 longest_reg_bits)
{
	int i;
	__u16 start_bit = (smallest_reg_bits - 1) % BITS_PER_BYTE;
	__u8 *last_byte = &header[len - 1];

	if(start_bit == 0)
		start_bit = 1;	/* must have at least one bit in the hdr */
	
	for(i=0; i < len; i++)
		header[i] = 0;

	for(i = start_bit; i > 0; i--)
		*last_byte = ((*last_byte) << 1) + 1;

}

static int
cat_sendinst(voyager_module_t *modp, voyager_asic_t *asicp, __u8 reg, __u8 op)
{
	__u8 parity, inst, inst_buf[4] = { 0 };
	__u8 iseq[VOYAGER_MAX_SCAN_PATH], hseq[VOYAGER_MAX_REG_SIZE];
	__u16 ibytes, hbytes, padbits;
	int i;
	
	/* 
	 * Parity is the parity of the register number + 1 (READ_REGISTER
	 * and WRITE_REGISTER always add '1' to the number of bits == 1)
	 */
	parity = (__u8)(1 + (reg & 0x01) +
	         ((__u8)(reg & 0x02) >> 1) +
	         ((__u8)(reg & 0x04) >> 2) +
	         ((__u8)(reg & 0x08) >> 3)) % 2;

	inst = ((parity << 7) | (reg << 2) | op);

	outb(VOYAGER_CAT_IRCYC, CAT_CMD);
	if(!modp->scan_path_connected) {
		if(asicp->asic_id != VOYAGER_CAT_ID) {
			printk("**WARNING***: cat_sendinst has disconnected scan path not to CAT asic\n");
			return 1;
		}
		outb(VOYAGER_CAT_HEADER, CAT_DATA);
		outb(inst, CAT_DATA);
		if(inb(CAT_DATA) != VOYAGER_CAT_HEADER) {
			CDEBUG(("VOYAGER CAT: cat_sendinst failed to get CAT_HEADER\n"));
			return 1;
		}
		return 0;
	}
	ibytes = modp->inst_bits / BITS_PER_BYTE;
	if((padbits = modp->inst_bits % BITS_PER_BYTE) != 0) {
		padbits = BITS_PER_BYTE - padbits;
		ibytes++;
	}
	hbytes = modp->largest_reg / BITS_PER_BYTE;
	if(modp->largest_reg % BITS_PER_BYTE)
		hbytes++;
	CDEBUG(("cat_sendinst: ibytes=%d, hbytes=%d\n", ibytes, hbytes));
	/* initialise the instruction sequence to 0xff */
	for(i=0; i < ibytes + hbytes; i++)
		iseq[i] = 0xff;
	cat_build_header(hseq, hbytes, modp->smallest_reg, modp->largest_reg);
	cat_pack(iseq, modp->inst_bits, hseq, hbytes * BITS_PER_BYTE);
	inst_buf[0] = inst;
	inst_buf[1] = 0xFF >> (modp->largest_reg % BITS_PER_BYTE);
	cat_pack(iseq, asicp->bit_location, inst_buf, asicp->ireg_length);
#ifdef VOYAGER_CAT_DEBUG
	printk("ins = 0x%x, iseq: ", inst);
	for(i=0; i< ibytes + hbytes; i++)
		printk("0x%x ", iseq[i]);
	printk("\n");
#endif
	if(cat_shiftout(iseq, ibytes, hbytes, padbits)) {
		CDEBUG(("VOYAGER CAT: cat_sendinst: cat_shiftout failed\n"));
		return 1;
	}
	CDEBUG(("CAT SHIFTOUT DONE\n"));
	return 0;
}

static int
cat_getdata(voyager_module_t *modp, voyager_asic_t *asicp, __u8 reg, 
	    __u8 *value)
{
	if(!modp->scan_path_connected) {
		if(asicp->asic_id != VOYAGER_CAT_ID) {
			CDEBUG(("VOYAGER CAT: ERROR: cat_getdata to CAT asic with scan path connected\n"));
			return 1;
		}
		if(reg > VOYAGER_SUBADDRHI) 
			outb(VOYAGER_CAT_RUN, CAT_CMD);
		outb(VOYAGER_CAT_DRCYC, CAT_CMD);
		outb(VOYAGER_CAT_HEADER, CAT_DATA);
		*value = inb(CAT_DATA);
		outb(0xAA, CAT_DATA);
		if(inb(CAT_DATA) != VOYAGER_CAT_HEADER) {
			CDEBUG(("cat_getdata: failed to get VOYAGER_CAT_HEADER\n"));
			return 1;
		}
		return 0;
	}
	else {
		__u16 sbits = modp->num_asics -1 + asicp->ireg_length;
		__u16 sbytes = sbits / BITS_PER_BYTE;
		__u16 tbytes;
		__u8 string[VOYAGER_MAX_SCAN_PATH], trailer[VOYAGER_MAX_REG_SIZE];
		__u8 padbits;
		int i;
		
		outb(VOYAGER_CAT_DRCYC, CAT_CMD);

		if((padbits = sbits % BITS_PER_BYTE) != 0) {
			padbits = BITS_PER_BYTE - padbits;
			sbytes++;
		}
		tbytes = asicp->ireg_length / BITS_PER_BYTE;
		if(asicp->ireg_length % BITS_PER_BYTE)
			tbytes++;
		CDEBUG(("cat_getdata: tbytes = %d, sbytes = %d, padbits = %d\n",
			tbytes,	sbytes, padbits));
		cat_build_header(trailer, tbytes, 1, asicp->ireg_length);

		
		for(i = tbytes - 1; i >= 0; i--) {
			outb(trailer[i], CAT_DATA);
			string[sbytes + i] = inb(CAT_DATA);
		}

		for(i = sbytes - 1; i >= 0; i--) {
			outb(0xaa, CAT_DATA);
			string[i] = inb(CAT_DATA);
		}
		*value = 0;
		cat_unpack(string, padbits + (tbytes * BITS_PER_BYTE) + asicp->asic_location, value, asicp->ireg_length);
#ifdef VOYAGER_CAT_DEBUG
		printk("value=0x%x, string: ", *value);
		for(i=0; i< tbytes+sbytes; i++)
			printk("0x%x ", string[i]);
		printk("\n");
#endif
		
		/* sanity check the rest of the return */
		for(i=0; i < tbytes; i++) {
			__u8 input = 0;

			cat_unpack(string, padbits + (i * BITS_PER_BYTE), &input, BITS_PER_BYTE);
			if(trailer[i] != input) {
				CDEBUG(("cat_getdata: failed to sanity check rest of ret(%d) 0x%x != 0x%x\n", i, input, trailer[i]));
				return 1;
			}
		}
		CDEBUG(("cat_getdata DONE\n"));
		return 0;
	}
}

static int
cat_shiftout(__u8 *data, __u16 data_bytes, __u16 header_bytes, __u8 pad_bits)
{
	int i;
	
	for(i = data_bytes + header_bytes - 1; i >= header_bytes; i--)
		outb(data[i], CAT_DATA);

	for(i = header_bytes - 1; i >= 0; i--) {
		__u8 header = 0;
		__u8 input;

		outb(data[i], CAT_DATA);
		input = inb(CAT_DATA);
		CDEBUG(("cat_shiftout: returned 0x%x\n", input));
		cat_unpack(data, ((data_bytes + i) * BITS_PER_BYTE) - pad_bits,
			   &header, BITS_PER_BYTE);
		if(input != header) {
			CDEBUG(("VOYAGER CAT: cat_shiftout failed to return header 0x%x != 0x%x\n", input, header));
			return 1;
		}
	}
	return 0;
}

static int
cat_senddata(voyager_module_t *modp, voyager_asic_t *asicp, 
	     __u8 reg, __u8 value)
{
	outb(VOYAGER_CAT_DRCYC, CAT_CMD);
	if(!modp->scan_path_connected) {
		if(asicp->asic_id != VOYAGER_CAT_ID) {
			CDEBUG(("VOYAGER CAT: ERROR: scan path disconnected when asic != CAT\n"));