arch/alpha/kernel/sys_eb64p.c

   1 /*
   2  *      linux/arch/alpha/kernel/sys_eb64p.c
   3  *
   4  *      Copyright (C) 1995 David A Rusling
   5  *      Copyright (C) 1996 Jay A Estabrook
   6  *      Copyright (C) 1998, 1999 Richard Henderson
   7  *
   8  * Code supporting the EB64+ and EB66.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/types.h>
  13 #include <linux/mm.h>
  14 #include <linux/sched.h>
  15 #include <linux/pci.h>
  16 #include <linux/init.h>
  17 #include <linux/bitops.h>
  18
  19 #include <asm/ptrace.h>
  20 #include <asm/system.h>
  21 #include <asm/dma.h>
  22 #include <asm/irq.h>
  23 #include <asm/mmu_context.h>
  24 #include <asm/io.h>
  25 #include <asm/pgtable.h>
  26 #include <asm/core_apecs.h>
  27 #include <asm/core_lca.h>
  28 #include <asm/hwrpb.h>
  29 #include <asm/tlbflush.h>
  30
  31 #include "proto.h"
  32 #include "irq_impl.h"
  33 #include "pci_impl.h"
  34 #include "machvec_impl.h"
  35
  36
  37 /* Note mask bit is true for DISABLED irqs.  */
  38 static unsigned int cached_irq_mask = -1;
  39
  40 static inline void
  41 eb64p_update_irq_hw(unsigned int irq, unsigned long mask)
  42 {
  43         outb(mask >> (irq >= 24 ? 24 : 16), (irq >= 24 ? 0x27 : 0x26));
  44 }
  45
  46 static inline void
  47 eb64p_enable_irq(unsigned int irq)
  48 {
  49         eb64p_update_irq_hw(irq, cached_irq_mask &= ~(1 << irq));
  50 }
  51
  52 static void
  53 eb64p_disable_irq(unsigned int irq)
  54 {
  55         eb64p_update_irq_hw(irq, cached_irq_mask |= 1 << irq);
  56 }
  57
  58 static unsigned int
  59 eb64p_startup_irq(unsigned int irq)
  60 {
  61         eb64p_enable_irq(irq);
  62         return 0; /* never anything pending */
  63 }
  64
  65 static void
  66 eb64p_end_irq(unsigned int irq)
  67 {
  68         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  69                 eb64p_enable_irq(irq);
  70 }
  71
  72 static struct irq_chip eb64p_irq_type = {
  73         .name           = "EB64P",
  74         .startup        = eb64p_startup_irq,
  75         .shutdown       = eb64p_disable_irq,
  76         .enable         = eb64p_enable_irq,
  77         .disable        = eb64p_disable_irq,
  78         .ack            = eb64p_disable_irq,
  79         .end            = eb64p_end_irq,
  80 };
  81
  82 static void
  83 eb64p_device_interrupt(unsigned long vector)
  84 {
  85         unsigned long pld;
  86         unsigned int i;
  87
  88         /* Read the interrupt summary registers */
  89         pld = inb(0x26) | (inb(0x27) << 8);
  90
  91         /*
  92          * Now, for every possible bit set, work through
  93          * them and call the appropriate interrupt handler.
  94          */
  95         while (pld) {
  96                 i = ffz(~pld);
  97                 pld &= pld - 1; /* clear least bit set */
  98
  99                 if (i == 5) {
 100                         isa_device_interrupt(vector);
 101                 } else {
 102                         handle_irq(16 + i);
 103                 }
 104         }
 105 }
 106
 107 static void __init
 108 eb64p_init_irq(void)
 109 {
 110         long i;
 111
 112 #if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_CABRIOLET)
 113         /*
 114          * CABRIO SRM may not set variation correctly, so here we test
 115          * the high word of the interrupt summary register for the RAZ
 116          * bits, and hope that a true EB64+ would read all ones...
 117          */
 118         if (inw(0x806) != 0xffff) {
 119                 extern struct alpha_machine_vector cabriolet_mv;
 120
 121                 printk("Detected Cabriolet: correcting HWRPB.\n");
 122
 123                 hwrpb->sys_variation |= 2L << 10;
 124                 hwrpb_update_checksum(hwrpb);
 125
 126                 alpha_mv = cabriolet_mv;
 127                 alpha_mv.init_irq();
 128                 return;
 129         }
 130 #endif /* GENERIC */
 131
 132         outb(0xff, 0x26);
 133         outb(0xff, 0x27);
 134
 135         init_i8259a_irqs();
 136
 137         for (i = 16; i < 32; ++i) {
 138                 irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
 139                 irq_desc[i].chip = &eb64p_irq_type;
 140         }
 141
 142         common_init_isa_dma();
 143         setup_irq(16+5, &isa_cascade_irqaction);
 144 }
 145
 146 /*
 147  * PCI Fixup configuration.
 148  *
 149  * There are two 8 bit external summary registers as follows:
 150  *
 151  * Summary @ 0x26:
 152  * Bit      Meaning
 153  * 0        Interrupt Line A from slot 0
 154  * 1        Interrupt Line A from slot 1
 155  * 2        Interrupt Line B from slot 0
 156  * 3        Interrupt Line B from slot 1
 157  * 4        Interrupt Line C from slot 0
 158  * 5        Interrupt line from the two ISA PICs
 159  * 6        Tulip
 160  * 7        NCR SCSI
 161  *
 162  * Summary @ 0x27
 163  * Bit      Meaning
 164  * 0        Interrupt Line C from slot 1
 165  * 1        Interrupt Line D from slot 0
 166  * 2        Interrupt Line D from slot 1
 167  * 3        RAZ
 168  * 4        RAZ
 169  * 5        RAZ
 170  * 6        RAZ
 171  * 7        RAZ
 172  *
 173  * The device to slot mapping looks like:
 174  *
 175  * Slot     Device
 176  *  5       NCR SCSI controller
 177  *  6       PCI on board slot 0
 178  *  7       PCI on board slot 1
 179  *  8       Intel SIO PCI-ISA bridge chip
 180  *  9       Tulip - DECchip 21040 Ethernet controller
 181  *
 182  *
 183  * This two layered interrupt approach means that we allocate IRQ 16 and
 184  * above for PCI interrupts.  The IRQ relates to which bit the interrupt
 185  * comes in on.  This makes interrupt processing much easier.
 186  */
 187
 188 static int __init
 189 eb64p_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
 190 {
 191         static char irq_tab[5][5] __initdata = {
 192                 /*INT  INTA  INTB  INTC   INTD */
 193                 {16+7, 16+7, 16+7, 16+7,  16+7},  /* IdSel 5,  slot ?, ?? */
 194                 {16+0, 16+0, 16+2, 16+4,  16+9},  /* IdSel 6,  slot ?, ?? */
 195                 {16+1, 16+1, 16+3, 16+8, 16+10},  /* IdSel 7,  slot ?, ?? */
 196                 {  -1,   -1,   -1,   -1,    -1},  /* IdSel 8,  SIO */
 197                 {16+6, 16+6, 16+6, 16+6,  16+6},  /* IdSel 9,  TULIP */
 198         };
 199         const long min_idsel = 5, max_idsel = 9, irqs_per_slot = 5;
 200         return COMMON_TABLE_LOOKUP;
 201 }
 202
 203
 204 /*
 205  * The System Vector
 206  */
 207
 208 #if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_EB64P)
 209 struct alpha_machine_vector eb64p_mv __initmv = {
 210         .vector_name            = "EB64+",
 211         DO_EV4_MMU,
 212         DO_DEFAULT_RTC,
 213         DO_APECS_IO,
 214         .machine_check          = apecs_machine_check,
 215         .max_isa_dma_address    = ALPHA_MAX_ISA_DMA_ADDRESS,
 216         .min_io_address         = DEFAULT_IO_BASE,
 217         .min_mem_address        = APECS_AND_LCA_DEFAULT_MEM_BASE,
 218
 219         .nr_irqs                = 32,
 220         .device_interrupt       = eb64p_device_interrupt,
 221
 222         .init_arch              = apecs_init_arch,
 223         .init_irq               = eb64p_init_irq,
 224         .init_rtc               = common_init_rtc,
 225         .init_pci               = common_init_pci,
 226         .kill_arch              = NULL,
 227         .pci_map_irq            = eb64p_map_irq,
 228         .pci_swizzle            = common_swizzle,
 229 };
 230 ALIAS_MV(eb64p)
 231 #endif
 232
 233 #if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_EB66)
 234 struct alpha_machine_vector eb66_mv __initmv = {
 235         .vector_name            = "EB66",
 236         DO_EV4_MMU,
 237         DO_DEFAULT_RTC,
 238         DO_LCA_IO,
 239         .machine_check          = lca_machine_check,
 240         .max_isa_dma_address    = ALPHA_MAX_ISA_DMA_ADDRESS,
 241         .min_io_address         = DEFAULT_IO_BASE,
 242         .min_mem_address        = APECS_AND_LCA_DEFAULT_MEM_BASE,
 243
 244         .nr_irqs                = 32,
 245         .device_interrupt       = eb64p_device_interrupt,
 246
 247         .init_arch              = lca_init_arch,
 248         .init_irq               = eb64p_init_irq,
 249         .init_rtc               = common_init_rtc,
 250         .init_pci               = common_init_pci,
 251         .pci_map_irq            = eb64p_map_irq,
 252         .pci_swizzle            = common_swizzle,
 253 };
 254 ALIAS_MV(eb66)
 255 #endif