drivers/block/macide.c

   1 /*
   2  *  linux/drivers/block/macide.c -- Macintosh IDE Driver
   3  *
   4  *     Copyright (C) 1998 by Michael Schmitz
   5  *
   6  *  This driver was written based on information obtained from the MacOS IDE
   7  *  driver binary by Mikael Forselius
   8  *
   9  *  This file is subject to the terms and conditions of the GNU General Public
  10  *  License.  See the file COPYING in the main directory of this archive for
  11  *  more details.
  12  */
  13
  14 #include <linux/types.h>
  15 #include <linux/mm.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/blkdev.h>
  18 #include <linux/hdreg.h>
  19 #include <linux/zorro.h>
  20 #include <linux/ide.h>
  21
  22 #include <asm/machw.h>
  23 #include <asm/macintosh.h>
  24 #include <asm/macints.h>
  25
  26     /*
  27      *  Base of the IDE interface (see ATAManager ROM code)
  28      */
  29
  30 #define MAC_HD_BASE     0x50f1a000
  31
  32     /*
  33      *  Offsets from the above base (scaling 4)
  34      */
  35
  36 #define MAC_HD_DATA     0x00
  37 #define MAC_HD_ERROR    0x04            /* see err-bits */
  38 #define MAC_HD_NSECTOR  0x08            /* nr of sectors to read/write */
  39 #define MAC_HD_SECTOR   0x0c            /* starting sector */
  40 #define MAC_HD_LCYL     0x10            /* starting cylinder */
  41 #define MAC_HD_HCYL     0x14            /* high byte of starting cyl */
  42 #define MAC_HD_SELECT   0x18            /* 101dhhhh , d=drive, hhhh=head */
  43 #define MAC_HD_STATUS   0x1c            /* see status-bits */
  44 #define MAC_HD_CONTROL  0x38            /* control/altstatus */
  45
  46 static int macide_offsets[IDE_NR_PORTS] = {
  47     MAC_HD_DATA, MAC_HD_ERROR, MAC_HD_NSECTOR, MAC_HD_SECTOR, MAC_HD_LCYL,
  48     MAC_HD_HCYL, MAC_HD_SELECT, MAC_HD_STATUS, MAC_HD_CONTROL
  49 };
  50
  51         /*
  52          * Other registers
  53          */
  54
  55         /*
  56          * IDE interrupt status register for both (?) hwifs on Quadra
  57          * Initial setting: 0xc
  58          * Guessing again:
  59          * Bit 0+1: some interrupt flags
  60          * Bit 2+3: some interrupt enable
  61          * Bit 4:   ??
  62          * Bit 5:   IDE interrupt flag (any hwif)
  63          * Bit 6:   maybe IDE interrupt enable (any hwif) ??
  64          * Bit 7:   Any interrupt condition
  65          *
  66          * Only relevant item: bit 5, to be checked by mac_ack_intr
  67          */
  68
  69 #define MAC_HD_ISR      0x101
  70
  71         /*
  72          * IDE interrupt glue - seems to be wired to Nubus, Slot C?
  73          * (ROM code disassembly again)
  74          * First try: just use Nubus interrupt for Slot C. Have Nubus code call
  75          * a wrapper to ide_intr that checks the ISR (see above).
  76          * Need to #define IDE_IRQ_NUBUS though.
  77          * Alternative method: set a mac_ide_hook function pointer to the wrapper
  78          * here and have via_do_nubus call that hook if set.
  79          *
  80          * Quadra needs the hook, Powerbook can use Nubus slot C.
  81          * Checking the ISR on Quadra is done by mac_ack_intr (see Amiga code). mac_ide_intr
  82          * mac_ide_intr is obsolete except for providing the hwgroup argument.
  83          */
  84
  85         /* The Mac hwif data, for passing hwgroup to ide_intr */
  86 static ide_hwif_t *mac_hwif = NULL;
  87
  88         /* The function pointer used in the Nubus handler */
  89 void (*mac_ide_intr_hook)(int, void *, struct pt_regs *) = NULL;
  90
  91         /*
  92          * Only purpose: feeds the hwgroup to the main IDE handler.
  93          * Obsolete as soon as Nubus code is fixed WRT pseudo slot C int.
  94          * (should be the case on Powerbooks)
  95          * Alas, second purpose: feed correct irq to IDE handler (I know,
  96          * that's cheating) :-(((
  97          * Fix needed for interrupt code: accept Nubus ints in the regular
  98          * request_irq code, then register Powerbook IDE as Nubus slot C,
  99          * Quadra as slot F (F for fictious).
 100          */
 101 void mac_ide_intr(int irq, void *dev_id, struct pt_regs *regs)
 102 {
 103         ide_intr(mac_hwif->irq, mac_hwif->hwgroup, regs);
 104 }
 105
 106     /*
 107      *  Check the interrupt status
 108      *
 109      *  Note: In 2.0 kernels, there have been timing problems with the
 110      *  Powerbook IDE interface (BUSY was asserted too long after the
 111      *  interrupt triggered). Result: repeated errors, recalibrate etc.
 112      *  Adding a wait loop to read_intr, write_intr and set_geom_intr
 113      *  fixed the problem (waits in read/write_intr were present for Amiga
 114      *  already).
 115      *  Powerbooks were not tested with 2.1 due to lack of FPU emulation
 116      *  (thanks Apple for using LC040). If the BUSY problem resurfaces in
 117      *  2.1, my best bet would be to add the wait loop right here, afterr
 118      *  checking the interrupt register.
 119      */
 120
 121 static int mac_ack_intr(ide_hwif_t *hwif)
 122 {
 123     unsigned char ch;
 124
 125     ch = inb(hwif->io_ports[IDE_IRQ_OFFSET]);
 126     if (!(ch & 0x20))
 127         return 0;
 128     return 1;
 129 }
 130
 131     /*
 132      *  Probe for a Macintosh IDE interface
 133      */
 134
 135 void macide_init(void)
 136 {
 137     hw_regs_t hw;
 138     int index = -1;
 139
 140     if (MACH_IS_MAC) {
 141         switch(macintosh_config->ide_type) {
 142         case 0:
 143             break;
 144
 145         case MAC_IDE_QUADRA:
 146             ide_setup_ports(&hw, (ide_ioreg_t)MAC_HD_BASE, macide_offsets,
 147                             0, (ide_ioreg_t)(MAC_HD_BASE+MAC_HD_ISR),
 148                             mac_ack_intr, IRQ_MAC_NUBUS);
 149             index = ide_register_hw(&hw, &mac_hwif);
 150             mac_ide_intr_hook = mac_ide_intr;
 151             break;
 152
 153         default:
 154             ide_setup_ports(&hw, (ide_ioreg_t)MAC_HD_BASE, macide_offsets,
 155                             0, 0, NULL, IRQ_MAC_NUBUS);
 156             index = ide_register_hw(&hw, &mac_hwif);
 157             break;
 158         }
 159
 160         if (index != -1) {
 161             if (macintosh_config->ide_type == MAC_IDE_QUADRA)
 162                 printk("ide%d: Macintosh Quadra IDE interface\n", index);
 163             else
 164                 printk("ide%d: Macintosh Powerbook IDE interface\n", index);
 165         }
 166     }
 167 }