eisa_enumerator.c

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/*
 * eisa_enumerator.c - provide support for EISA adapters in PA-RISC machines
 *
 * 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.
 *
 * Copyright (c) 2002 Daniel Engstrom <[email protected]>
 *
 */

#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>

#include <asm/eisa_bus.h>
#include <asm/eisa_eeprom.h>


/*
 * Todo:
 * 
 * PORT init with MASK attr and other size than byte
 * MEMORY with other decode than 20 bit
 * CRC stuff
 * FREEFORM stuff
 */

#define EPI 0xc80
#define NUM_SLOT 16
#define SLOT2PORT(x) (x<<12)


/* macros to handle unaligned accesses and 
 * byte swapping. The data in the EEPROM is
 * little-endian on the big-endian PAROSC */
#define get_8(x) (*(u_int8_t*)(x))

static inline u_int16_t get_16(const unsigned char *x)
{ 
    return (x[1] << 8) | x[0];
}

static inline u_int32_t get_32(const unsigned char *x)
{
    return (x[3] << 24) | (x[2] << 16) | (x[1] << 8) | x[0];
}

static inline u_int32_t get_24(const unsigned char *x)
{
    return (x[2] << 24) | (x[1] << 16) | (x[0] << 8);
}

static void print_eisa_id(char *s, u_int32_t id)
{
    char vendor[4];
    int rev;
    int device;
    
    rev = id & 0xff;
    id >>= 8;
    device = id & 0xff;
    id >>= 8;
    vendor[3] = '\0';
    vendor[2] = '@' + (id & 0x1f);
    id >>= 5;   
    vendor[1] = '@' + (id & 0x1f);
    id >>= 5;   
    vendor[0] = '@' + (id & 0x1f);
    id >>= 5;   
    
    sprintf(s, "%s%02X%02X", vendor, device, rev);
}
       
static int configure_memory(const unsigned char *buf, 
               struct resource *mem_parent,
               char *name)
{
    int len;
    u_int8_t c;
    int i;
    struct resource *res;
    
    len=0;
    
    for (i=0;i<HPEE_MEMORY_MAX_ENT;i++) {
        c = get_8(buf+len);
        
        if (NULL != (res = kmalloc(sizeof(struct resource), GFP_KERNEL))) {
            int result;
            
            res->name = name;
            res->start = mem_parent->start + get_24(buf+len+2);
            res->end = res->start + get_16(buf+len+5)*1024;
            res->flags = IORESOURCE_MEM;
            printk("memory %lx-%lx ", (unsigned long)res->start, (unsigned long)res->end);
            result = request_resource(mem_parent, res);
            if (result < 0) {
                printk(KERN_ERR "EISA Enumerator: failed to claim EISA Bus address space!\n");
                return result;
            }
        }
            
        len+=7;      
    
        if (!(c & HPEE_MEMORY_MORE)) {
            break;
        }
    }
    
    return len;
}


static int configure_irq(const unsigned char *buf)
{
    int len;
    u_int8_t c;
    int i;
    
    len=0;
    
    for (i=0;i<HPEE_IRQ_MAX_ENT;i++) {
        c = get_8(buf+len);
        
        printk("IRQ %d ", c & HPEE_IRQ_CHANNEL_MASK);
        if (c & HPEE_IRQ_TRIG_LEVEL) {
            eisa_make_irq_level(c & HPEE_IRQ_CHANNEL_MASK);
        } else {
            eisa_make_irq_edge(c & HPEE_IRQ_CHANNEL_MASK);
        }
        
        len+=2; 
        /* hpux seems to allow for
         * two bytes of irq data but only defines one of
         * them, I think */
        if  (!(c & HPEE_IRQ_MORE)) {
            break;
        }
    }
    
    return len;
}


static int configure_dma(const unsigned char *buf)
{
    int len;
    u_int8_t c;
    int i;
    
    len=0;
    
    for (i=0;i<HPEE_DMA_MAX_ENT;i++) {
        c = get_8(buf+len);
        printk("DMA %d ", c&HPEE_DMA_CHANNEL_MASK);
        /* fixme: maybe initialize the dma channel withthe timing ? */
        len+=2;      
        if (!(c & HPEE_DMA_MORE)) {
            break;
        }
    }
    
    return len;
}

static int configure_port(const unsigned char *buf, struct resource *io_parent,
             char *board)
{
    int len;
    u_int8_t c;
    int i;
    struct resource *res;
    int result;
    
    len=0;
    
    for (i=0;i<HPEE_PORT_MAX_ENT;i++) {
        c = get_8(buf+len);
        
        if (NULL != (res = kmalloc(sizeof(struct resource), GFP_KERNEL))) {
            res->name = board;
            res->start = get_16(buf+len+1);
            res->end = get_16(buf+len+1)+(c&HPEE_PORT_SIZE_MASK)+1;
            res->flags = IORESOURCE_IO;
            printk("ioports %lx-%lx ", (unsigned long)res->start, (unsigned long)res->end);
            result = request_resource(io_parent, res);
            if (result < 0) {
                printk(KERN_ERR "EISA Enumerator: failed to claim EISA Bus address space!\n");
                return result;
            }
        }

        len+=3;      
        if (!(c & HPEE_PORT_MORE)) {
            break;
        }
    }
    
    return len;
}


/* byte 1 and 2 is the port number to write
 * and at byte 3 the value to write starts.
 * I assume that there are and- and or- masks
 * here when HPEE_PORT_INIT_MASK is set but I have 
 * not yet encountered this. */
static int configure_port_init(const unsigned char *buf)
{
    int len=0;
    u_int8_t c;
    
    while (len<HPEE_PORT_INIT_MAX_LEN) {
        int s=0;
        c = get_8(buf+len);
        
        switch (c & HPEE_PORT_INIT_WIDTH_MASK)  {
         case HPEE_PORT_INIT_WIDTH_BYTE:
            s=1;
            if (c & HPEE_PORT_INIT_MASK) {
                printk(KERN_WARNING "port_init: unverified mask attribute\n");
                outb((inb(get_16(buf+len+1) & 
                      get_8(buf+len+3)) | 
                      get_8(buf+len+4)), get_16(buf+len+1));
                      
            } else {
                outb(get_8(buf+len+3), get_16(buf+len+1));
                      
            }
            break;
         case HPEE_PORT_INIT_WIDTH_WORD:
            s=2;
            if (c & HPEE_PORT_INIT_MASK) {
                printk(KERN_WARNING "port_init: unverified mask attribute\n");
                       outw((inw(get_16(buf+len+1)) &
                         get_16(buf+len+3)) |
                        get_16(buf+len+5), 
                        get_16(buf+len+1));
            } else {
                outw(cpu_to_le16(get_16(buf+len+3)), get_16(buf+len+1));
            }
            break;
         case HPEE_PORT_INIT_WIDTH_DWORD:
            s=4;
            if (c & HPEE_PORT_INIT_MASK) {
                printk(KERN_WARNING "port_init: unverified mask attribute\n");
                outl((inl(get_16(buf+len+1) &
                      get_32(buf+len+3)) |
                      get_32(buf+len+7)), get_16(buf+len+1));
            } else {
                outl(cpu_to_le32(get_32(buf+len+3)), get_16(buf+len+1));
            }

            break;
         default:
            printk(KERN_ERR "Invalid port init word %02x\n", c);
            return 0;
        }
        
        if (c & HPEE_PORT_INIT_MASK) {   
            s*=2;
        }
        
        len+=s+3;
        if (!(c & HPEE_PORT_INIT_MORE)) {
            break;
        }
    }
    
    return len;
}

static int configure_choise(const unsigned char *buf, u_int8_t *info)
{
    int len;
    
    /* theis record contain the value of the functions
     * configuration choises and an info byte which 
     * describes which other records to expect in this 
     * function */
    len = get_8(buf);
    *info=get_8(buf+len+1);
     
    return len+2;
}

static int configure_type_string(const unsigned char *buf) 
{
    int len;
    
    /* just skip past the type field */
    len = get_8(buf);
    if (len > 80) {
        printk(KERN_ERR "eisa_enumerator: type info field too long (%d, max is 80)\n", len);
    }
    
    return 1+len;
}

static int configure_function(const unsigned char *buf, int *more) 
{
    /* the init field seems to be a two-byte field
     * which is non-zero if there are an other function following
     * I think it is the length of the function def 
     */
    *more = get_16(buf);
    
    return 2;
}

static int parse_slot_config(int slot,
                 const unsigned char *buf,
                 struct eeprom_eisa_slot_info *es, 
                 struct resource *io_parent,
                 struct resource *mem_parent)
{
    int res=0;
    int function_len;
    unsigned int pos=0;
    unsigned int maxlen;
    int num_func=0;
    u_int8_t flags;
    int p0;
    
    char *board;
    int id_string_used=0;
    
    if (NULL == (board = kmalloc(8, GFP_KERNEL))) {
        return -1;
    }
    print_eisa_id(board, es->eisa_slot_id);
    printk(KERN_INFO "EISA slot %d: %s %s ", 
           slot, board, es->flags&HPEE_FLAG_BOARD_IS_ISA ? "ISA" : "EISA");
    
    maxlen = es->config_data_length < HPEE_MAX_LENGTH ?
             es->config_data_length : HPEE_MAX_LENGTH;
    while ((pos < maxlen) && (num_func <= es->num_functions)) {
        pos+=configure_function(buf+pos, &function_len); 
        
        if (!function_len) {
            break;
        }
        num_func++;
        p0 = pos;
        pos += configure_choise(buf+pos, &flags);

        if (flags & HPEE_FUNCTION_INFO_F_DISABLED) {
            /* function disabled, skip silently */
            pos = p0 + function_len;
            continue;
        }
        if (flags & HPEE_FUNCTION_INFO_CFG_FREE_FORM) {
            /* I have no idea how to handle this */
            printk("function %d have free-form confgiuration, skipping ",
                num_func);
            pos = p0 + function_len;
            continue;
        }

        /* the ordering of the sections need
         * more investigation.
         * Currently I think that memory comaed before IRQ
         * I assume the order is LSB to MSB in the 
         * info flags 
         * eg type, memory, irq, dma, port, HPEE_PORT_init 
         */

        if (flags & HPEE_FUNCTION_INFO_HAVE_TYPE) {
            pos += configure_type_string(buf+pos);
        }
        
        if (flags & HPEE_FUNCTION_INFO_HAVE_MEMORY) {
            id_string_used=1;
            pos += configure_memory(buf+pos, mem_parent, board);
        } 
        
        if (flags & HPEE_FUNCTION_INFO_HAVE_IRQ) {
            pos += configure_irq(buf+pos);
        } 
        
        if (flags & HPEE_FUNCTION_INFO_HAVE_DMA) {
            pos += configure_dma(buf+pos);
        } 
        
        if (flags & HPEE_FUNCTION_INFO_HAVE_PORT) {
            id_string_used=1;
            pos += configure_port(buf+pos, io_parent, board);
        } 
        
        if (flags &  HPEE_FUNCTION_INFO_HAVE_PORT_INIT) {
            pos += configure_port_init(buf+pos);
        }
        
        if (p0 + function_len < pos) {
            printk(KERN_ERR "eisa_enumerator: function %d length mis-match "
                   "got %d, expected %d\n",
                   num_func, pos-p0, function_len);
            res=-1;
            break;
        }
        pos = p0 + function_len;
    }
    printk("\n");
    if (!id_string_used) {
        kfree(board);
    }
    
    if (pos != es->config_data_length) {
        printk(KERN_ERR "eisa_enumerator: config data length mis-match got %d, expected %d\n",
            pos, es->config_data_length);
        res=-1;
    }
    
    if (num_func != es->num_functions) {
        printk(KERN_ERR "eisa_enumerator: number of functions mis-match got %d, expected %d\n",
            num_func, es->num_functions);
        res=-2;
    }
    
    return res;
    
}

static int init_slot(int slot, struct eeprom_eisa_slot_info *es)
{
    unsigned int id;
    
    char id_string[8];
    
    if (!(es->slot_info&HPEE_SLOT_INFO_NO_READID)) {
        /* try to read the id of the board in the slot */
        id = le32_to_cpu(inl(SLOT2PORT(slot)+EPI));
        
        if (0xffffffff == id) {
            /* Maybe we didn't expect a card to be here... */
            if (es->eisa_slot_id == 0xffffffff)
                return -1;
            
            /* this board is not here or it does not 
             * support readid 
             */
            printk(KERN_ERR "EISA slot %d a configured board was not detected (", 
                   slot);
            
            print_eisa_id(id_string, es->eisa_slot_id);
            printk(" expected %s)\n", id_string);
        
            return -1;  

        }
        if (es->eisa_slot_id != id) {
            print_eisa_id(id_string, id);
            printk(KERN_ERR "EISA slot %d id mis-match: got %s", 
                   slot, id_string);
            
            print_eisa_id(id_string, es->eisa_slot_id);
            printk(" expected %s\n", id_string);
        
            return -1;  
            
        }
    }
    
    /* now: we need to enable the board if 
     * it supports enabling and run through
     * the port init sction if present
     * and finally record any interrupt polarity
     */
    if (es->slot_features & HPEE_SLOT_FEATURES_ENABLE) {
        /* enable board */
        outb(0x01| inb(SLOT2PORT(slot)+EPI+4),
             SLOT2PORT(slot)+EPI+4);
    }
    
    return 0;
}


int eisa_enumerator(unsigned long eeprom_addr,
            struct resource *io_parent, struct resource *mem_parent) 
{
    int i;
    struct eeprom_header *eh;
    static char eeprom_buf[HPEE_MAX_LENGTH];
    
    for (i=0; i < HPEE_MAX_LENGTH; i++) {
        eeprom_buf[i] = gsc_readb(eeprom_addr+i);
    }
    
    printk(KERN_INFO "Enumerating EISA bus\n");
                
    eh = (struct eeprom_header*)(eeprom_buf);
    for (i=0;i<eh->num_slots;i++) {
        struct eeprom_eisa_slot_info *es;
        
        es = (struct eeprom_eisa_slot_info*)
            (&eeprom_buf[HPEE_SLOT_INFO(i)]);
            
        if (-1==init_slot(i+1, es)) {
            continue;
        }
        
        if (es->config_data_offset < HPEE_MAX_LENGTH) {
            if (parse_slot_config(i+1, &eeprom_buf[es->config_data_offset],
                          es, io_parent, mem_parent)) {
                return -1;
            }
        } else {
            printk (KERN_WARNING "EISA EEPROM offset 0x%x out of range\n",es->config_data_offset);
            return -1;
        }
    }
    return eh->num_slots;
}