grub-0.97/netboot/pci_io.c

/*
** Support for NE2000 PCI clones added David Monro June 1997
** Generalised to other NICs by Ken Yap July 1997
**
** Most of this is taken from:
**
** /usr/src/linux/drivers/pci/pci.c
** /usr/src/linux/include/linux/pci.h
** /usr/src/linux/arch/i386/bios32.c
** /usr/src/linux/include/linux/bios32.h
** /usr/src/linux/drivers/net/ne.c
*/
#define PCBIOS
#include "grub.h"
#include "pci.h"

#ifdef  CONFIG_PCI_DIRECT
#define  PCIBIOS_SUCCESSFUL                0x00

#define DEBUG 0

/*
 * Functions for accessing PCI configuration space with type 1 accesses
 */

#define CONFIG_CMD(bus, device_fn, where)   (0x80000000 | (bus << 16) | (device_fn << 8) | (where & ~3))

int pcibios_read_config_byte(unsigned int bus, unsigned int device_fn,
                   unsigned int where, uint8_t *value)
{
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    *value = inb(0xCFC + (where&3));
    return PCIBIOS_SUCCESSFUL;
}

int pcibios_read_config_word (unsigned int bus,
    unsigned int device_fn, unsigned int where, uint16_t *value)
{
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    *value = inw(0xCFC + (where&2));
    return PCIBIOS_SUCCESSFUL;
}

int pcibios_read_config_dword (unsigned int bus, unsigned int device_fn,
                 unsigned int where, uint32_t *value)
{
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    *value = inl(0xCFC);
    return PCIBIOS_SUCCESSFUL;
}

int pcibios_write_config_byte (unsigned int bus, unsigned int device_fn,
                 unsigned int where, uint8_t value)
{
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    outb(value, 0xCFC + (where&3));
    return PCIBIOS_SUCCESSFUL;
}

int pcibios_write_config_word (unsigned int bus, unsigned int device_fn,
                 unsigned int where, uint16_t value)
{
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    outw(value, 0xCFC + (where&2));
    return PCIBIOS_SUCCESSFUL;
}

int pcibios_write_config_dword (unsigned int bus, unsigned int device_fn, unsigned int where, uint32_t value)
{
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    outl(value, 0xCFC);
    return PCIBIOS_SUCCESSFUL;
}

#undef CONFIG_CMD

#else    /* CONFIG_PCI_DIRECT  not defined */

#if !defined(PCBIOS)
#error "The pcibios can only be used when the PCBIOS support is compiled in"
#endif


#define KERN_CODE_SEG 0X8
/* Stuff for asm */
#define save_flags(x) \
__asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */ :"memory")

#define cli() __asm__ __volatile__ ("cli": : :"memory")

#define restore_flags(x) \
__asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory")


static struct {
    unsigned long address;
    unsigned short segment;
} bios32_indirect = { 0, KERN_CODE_SEG };

static long pcibios_entry = 0;
static struct {
    unsigned long address;
    unsigned short segment;
} pci_indirect = { 0, KERN_CODE_SEG };

static unsigned long bios32_service(unsigned long service)
{
    unsigned char return_code;  /* %al */
    unsigned long address;      /* %ebx */
    unsigned long length;       /* %ecx */
    unsigned long entry;        /* %edx */
    unsigned long flags;

    save_flags(flags);
    __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
        "lcall (%%edi)"
#else
        "lcall *(%%edi)"
#endif
        : "=a" (return_code),
          "=b" (address),
          "=c" (length),
          "=d" (entry)
        : "0" (service),
          "1" (0),
          "D" (&bios32_indirect));
    restore_flags(flags);

    switch (return_code) {
        case 0:
            return address + entry;
        case 0x80:  /* Not present */
            printf("bios32_service(%d) : not present\n", service);
            return 0;
        default: /* Shouldn't happen */
            printf("bios32_service(%d) : returned %#X, mail drew@colorado.edu\n",
                service, return_code);
            return 0;
    }
}

int pcibios_read_config_byte(unsigned int bus,
        unsigned int device_fn, unsigned int where, uint8_t *value)
{
        unsigned long ret;
        unsigned long bx = (bus << 8) | device_fn;
        unsigned long flags;

        save_flags(flags);
        __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
        "lcall (%%esi)\n\t"
#else
        "lcall *(%%esi)\n\t"
#endif
                "jc 1f\n\t"
                "xor %%ah, %%ah\n"
                "1:"
                : "=c" (*value),
                  "=a" (ret)
                : "1" (PCIBIOS_READ_CONFIG_BYTE),
                  "b" (bx),
                  "D" ((long) where),
                  "S" (&pci_indirect));
        restore_flags(flags);
        return (int) (ret & 0xff00) >> 8;
}

int pcibios_read_config_word(unsigned int bus,
        unsigned int device_fn, unsigned int where, uint16_t *value)
{
        unsigned long ret;
        unsigned long bx = (bus << 8) | device_fn;
        unsigned long flags;

        save_flags(flags);
        __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
        "lcall (%%esi)\n\t"
#else
        "lcall *(%%esi)\n\t"
#endif
                "jc 1f\n\t"
                "xor %%ah, %%ah\n"
                "1:"
                : "=c" (*value),
                  "=a" (ret)
                : "1" (PCIBIOS_READ_CONFIG_WORD),
                  "b" (bx),
                  "D" ((long) where),
                  "S" (&pci_indirect));
        restore_flags(flags);
        return (int) (ret & 0xff00) >> 8;
}

int pcibios_read_config_dword(unsigned int bus,
        unsigned int device_fn, unsigned int where, uint32_t *value)
{
        unsigned long ret;
        unsigned long bx = (bus << 8) | device_fn;
        unsigned long flags;

        save_flags(flags);
        __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
        "lcall (%%esi)\n\t"
#else
        "lcall *(%%esi)\n\t"
#endif
                "jc 1f\n\t"
                "xor %%ah, %%ah\n"
                "1:"
                : "=c" (*value),
                  "=a" (ret)
                : "1" (PCIBIOS_READ_CONFIG_DWORD),
                  "b" (bx),
                  "D" ((long) where),
                  "S" (&pci_indirect));
        restore_flags(flags);
        return (int) (ret & 0xff00) >> 8;
}

int pcibios_write_config_byte (unsigned int bus,
    unsigned int device_fn, unsigned int where, uint8_t value)
{
    unsigned long ret;
    unsigned long bx = (bus << 8) | device_fn;
    unsigned long flags;

    save_flags(flags); cli();
    __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
        "lcall (%%esi)\n\t"
#else
        "lcall *(%%esi)\n\t"
#endif
        "jc 1f\n\t"
        "xor %%ah, %%ah\n"
        "1:"
        : "=a" (ret)
        : "0" (PCIBIOS_WRITE_CONFIG_BYTE),
          "c" (value),
          "b" (bx),
          "D" ((long) where),
          "S" (&pci_indirect));
    restore_flags(flags);
    return (int) (ret & 0xff00) >> 8;
}

int pcibios_write_config_word (unsigned int bus,
    unsigned int device_fn, unsigned int where, uint16_t value)
{
    unsigned long ret;
    unsigned long bx = (bus << 8) | device_fn;
    unsigned long flags;

    save_flags(flags); cli();
    __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
        "lcall (%%esi)\n\t"
#else
        "lcall *(%%esi)\n\t"
#endif
        "jc 1f\n\t"
        "xor %%ah, %%ah\n"
        "1:"
        : "=a" (ret)
        : "0" (PCIBIOS_WRITE_CONFIG_WORD),
          "c" (value),
          "b" (bx),
          "D" ((long) where),
          "S" (&pci_indirect));
    restore_flags(flags);
    return (int) (ret & 0xff00) >> 8;
}

int pcibios_write_config_dword (unsigned int bus,
    unsigned int device_fn, unsigned int where, uint32_t value)
{
    unsigned long ret;
    unsigned long bx = (bus << 8) | device_fn;
    unsigned long flags;

    save_flags(flags); cli();
    __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
        "lcall (%%esi)\n\t"
#else
        "lcall *(%%esi)\n\t"
#endif
        "jc 1f\n\t"
        "xor %%ah, %%ah\n"
        "1:"
        : "=a" (ret)
        : "0" (PCIBIOS_WRITE_CONFIG_DWORD),
          "c" (value),
          "b" (bx),
          "D" ((long) where),
          "S" (&pci_indirect));
    restore_flags(flags);
    return (int) (ret & 0xff00) >> 8;
}

static void check_pcibios(void)
{
    unsigned long signature;
    unsigned char present_status;
    unsigned char major_revision;
    unsigned char minor_revision;
    unsigned long flags;
    int pack;

    if ((pcibios_entry = bios32_service(PCI_SERVICE))) {
        pci_indirect.address = pcibios_entry;

        save_flags(flags);
        __asm__(
#ifdef ABSOLUTE_WITHOUT_ASTERISK
            "lcall (%%edi)\n\t"
#else
            "lcall *(%%edi)\n\t"
#endif
            "jc 1f\n\t"
            "xor %%ah, %%ah\n"
            "1:\tshl $8, %%eax\n\t"
            "movw %%bx, %%ax"
            : "=d" (signature),
              "=a" (pack)
            : "1" (PCIBIOS_PCI_BIOS_PRESENT),
              "D" (&pci_indirect)
            : "bx", "cx");
        restore_flags(flags);

        present_status = (pack >> 16) & 0xff;
        major_revision = (pack >> 8) & 0xff;
        minor_revision = pack & 0xff;
        if (present_status || (signature != PCI_SIGNATURE)) {
            printf("ERROR: BIOS32 says PCI BIOS, but no PCI "
                "BIOS????\n");
            pcibios_entry = 0;
        }
#if DEBUG
        if (pcibios_entry) {
            printf ("pcibios_init : PCI BIOS revision %hhX.%hhX"
                " entry at %#X\n", major_revision,
                minor_revision, pcibios_entry);
        }
#endif
    }
}

static void pcibios_init(void)
{
    union bios32 *check;
    unsigned char sum;
    int i, length;
    unsigned long bios32_entry = 0;

    EnterFunction("pcibios_init");
    /*
     * Follow the standard procedure for locating the BIOS32 Service
     * directory by scanning the permissible address range from
     * 0xe0000 through 0xfffff for a valid BIOS32 structure.
     *
     */

    for (check = (union bios32 *) 0xe0000; check <= (union bios32 *) 0xffff0; ++check) {
        if (check->fields.signature != BIOS32_SIGNATURE)
            continue;
        length = check->fields.length * 16;
        if (!length)
            continue;
        sum = 0;
        for (i = 0; i < length ; ++i)
            sum += check->chars[i];
        if (sum != 0)
            continue;
        if (check->fields.revision != 0) {
            printf("pcibios_init : unsupported revision %d at %#X, mail drew@colorado.edu\n",
                check->fields.revision, check);
            continue;
        }
#if DEBUG
        printf("pcibios_init : BIOS32 Service Directory "
            "structure at %#X\n", check);
#endif
        if (!bios32_entry) {
            if (check->fields.entry >= 0x100000) {
                printf("pcibios_init: entry in high "
                    "memory, giving up\n");
                return;
            } else {
                bios32_entry = check->fields.entry;
#if DEBUG
                printf("pcibios_init : BIOS32 Service Directory"
                    " entry at %#X\n", bios32_entry);
#endif
                bios32_indirect.address = bios32_entry;
            }
        }
    }
    if (bios32_entry)
        check_pcibios();
    LeaveFunction("pcibios_init");
}

#endif  /* CONFIG_PCI_DIRECT not defined*/

unsigned long pcibios_bus_base(unsigned int bus __unused)
{
    /* architecturally this must be 0 */
    return 0;
}

void find_pci(int type, struct pci_device *dev)
{
    EnterFunction("find_pci");
#ifndef CONFIG_PCI_DIRECT
    if (!pcibios_entry) {
        pcibios_init();
    }
    if (!pcibios_entry) {
        printf("pci_init: no BIOS32 detected\n");
        return;
    }
#endif
    LeaveFunction("find_pci");
    return scan_pci_bus(type, dev);
}