arch/alpha/kernel/sys_rx164.c

   1 /*
   2  *      linux/arch/alpha/kernel/sys_rx164.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 RX164 (PCA56+POLARIS).
   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_polaris.h>
  27 #include <asm/tlbflush.h>
  28
  29 #include "proto.h"
  30 #include "irq_impl.h"
  31 #include "pci_impl.h"
  32 #include "machvec_impl.h"
  33
  34
  35 /* Note mask bit is true for ENABLED irqs.  */
  36 static unsigned long cached_irq_mask;
  37
  38 static inline void
  39 rx164_update_irq_hw(unsigned long mask)
  40 {
  41         volatile unsigned int *irq_mask;
  42
  43         irq_mask = (void *)(POLARIS_DENSE_CONFIG_BASE + 0x74);
  44         *irq_mask = mask;
  45         mb();
  46         *irq_mask;
  47 }
  48
  49 static inline void
  50 rx164_enable_irq(unsigned int irq)
  51 {
  52         rx164_update_irq_hw(cached_irq_mask |= 1UL << (irq - 16));
  53 }
  54
  55 static void
  56 rx164_disable_irq(unsigned int irq)
  57 {
  58         rx164_update_irq_hw(cached_irq_mask &= ~(1UL << (irq - 16)));
  59 }
  60
  61 static unsigned int
  62 rx164_startup_irq(unsigned int irq)
  63 {
  64         rx164_enable_irq(irq);
  65         return 0;
  66 }
  67
  68 static void
  69 rx164_end_irq(unsigned int irq)
  70 {
  71         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  72                 rx164_enable_irq(irq);
  73 }
  74
  75 static struct hw_interrupt_type rx164_irq_type = {
  76         .typename       = "RX164",
  77         .startup        = rx164_startup_irq,
  78         .shutdown       = rx164_disable_irq,
  79         .enable         = rx164_enable_irq,
  80         .disable        = rx164_disable_irq,
  81         .ack            = rx164_disable_irq,
  82         .end            = rx164_end_irq,
  83 };
  84
  85 static void
  86 rx164_device_interrupt(unsigned long vector, struct pt_regs *regs)
  87 {
  88         unsigned long pld;
  89         volatile unsigned int *dirr;
  90         long i;
  91
  92         /* Read the interrupt summary register.  On Polaris, this is
  93            the DIRR register in PCI config space (offset 0x84).  */
  94         dirr = (void *)(POLARIS_DENSE_CONFIG_BASE + 0x84);
  95         pld = *dirr;
  96
  97         /*
  98          * Now for every possible bit set, work through them and call
  99          * the appropriate interrupt handler.
 100          */
 101         while (pld) {
 102                 i = ffz(~pld);
 103                 pld &= pld - 1; /* clear least bit set */
 104                 if (i == 20) {
 105                         isa_no_iack_sc_device_interrupt(vector, regs);
 106                 } else {
 107                         handle_irq(16+i, regs);
 108                 }
 109         }
 110 }
 111
 112 static void __init
 113 rx164_init_irq(void)
 114 {
 115         long i;
 116
 117         rx164_update_irq_hw(0);
 118         for (i = 16; i < 40; ++i) {
 119                 irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
 120                 irq_desc[i].handler = &rx164_irq_type;
 121         }
 122
 123         init_i8259a_irqs();
 124         common_init_isa_dma();
 125
 126         setup_irq(16+20, &isa_cascade_irqaction);
 127 }
 128
 129
 130 /*
 131  * The RX164 changed its interrupt routing between pass1 and pass2...
 132  *
 133  * PASS1:
 134  *
 135  *      Slot    IDSEL   INTA    INTB    INTC    INTD
 136  *      0       6       5       10      15      20
 137  *      1       7       4       9       14      19
 138  *      2       5       3       8       13      18
 139  *      3       9       2       7       12      17
 140  *      4       10      1       6       11      16
 141  *
 142  * PASS2:
 143  *      Slot    IDSEL   INTA    INTB    INTC    INTD
 144  *      0       5       1       7       12      17
 145  *      1       6       2       8       13      18
 146  *      2       8       3       9       14      19
 147  *      3       9       4       10      15      20
 148  *      4       10      5       11      16      6
 149  *
 150  */
 151
 152 /*
 153  * IdSel
 154  *   5  32 bit PCI option slot 0
 155  *   6  64 bit PCI option slot 1
 156  *   7  PCI-ISA bridge
 157  *   7  64 bit PCI option slot 2
 158  *   9  32 bit PCI option slot 3
 159  *  10  PCI-PCI bridge
 160  *
 161  */
 162
 163 static int __init
 164 rx164_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
 165 {
 166 #if 0
 167         static char irq_tab_pass1[6][5] __initdata = {
 168           /*INT   INTA  INTB  INTC   INTD */
 169           { 16+3, 16+3, 16+8, 16+13, 16+18},      /* IdSel 5,  slot 2 */
 170           { 16+5, 16+5, 16+10, 16+15, 16+20},     /* IdSel 6,  slot 0 */
 171           { 16+4, 16+4, 16+9, 16+14, 16+19},      /* IdSel 7,  slot 1 */
 172           { -1,     -1,    -1,    -1,   -1},      /* IdSel 8, PCI/ISA bridge */
 173           { 16+2, 16+2, 16+7, 16+12, 16+17},      /* IdSel 9,  slot 3 */
 174           { 16+1, 16+1, 16+6, 16+11, 16+16},      /* IdSel 10, slot 4 */
 175         };
 176 #else
 177         static char irq_tab[6][5] __initdata = {
 178           /*INT   INTA  INTB  INTC   INTD */
 179           { 16+0, 16+0, 16+6, 16+11, 16+16},      /* IdSel 5,  slot 0 */
 180           { 16+1, 16+1, 16+7, 16+12, 16+17},      /* IdSel 6,  slot 1 */
 181           { -1,     -1,    -1,    -1,   -1},      /* IdSel 7, PCI/ISA bridge */
 182           { 16+2, 16+2, 16+8, 16+13, 16+18},      /* IdSel 8,  slot 2 */
 183           { 16+3, 16+3, 16+9, 16+14, 16+19},      /* IdSel 9,  slot 3 */
 184           { 16+4, 16+4, 16+10, 16+15, 16+5},      /* IdSel 10, PCI-PCI */
 185         };
 186 #endif
 187         const long min_idsel = 5, max_idsel = 10, irqs_per_slot = 5;
 188
 189         /* JRP - Need to figure out how to distinguish pass1 from pass2,
 190            and use the correct table.  */
 191         return COMMON_TABLE_LOOKUP;
 192 }
 193
 194
 195 /*
 196  * The System Vector
 197  */
 198
 199 struct alpha_machine_vector rx164_mv __initmv = {
 200         .vector_name            = "RX164",
 201         DO_EV5_MMU,
 202         DO_DEFAULT_RTC,
 203         DO_POLARIS_IO,
 204         .machine_check          = polaris_machine_check,
 205         .max_isa_dma_address    = ALPHA_MAX_ISA_DMA_ADDRESS,
 206         .min_io_address         = DEFAULT_IO_BASE,
 207         .min_mem_address        = DEFAULT_MEM_BASE,
 208
 209         .nr_irqs                = 40,
 210         .device_interrupt       = rx164_device_interrupt,
 211
 212         .init_arch              = polaris_init_arch,
 213         .init_irq               = rx164_init_irq,
 214         .init_rtc               = common_init_rtc,
 215         .init_pci               = common_init_pci,
 216         .kill_arch              = NULL,
 217         .pci_map_irq            = rx164_map_irq,
 218         .pci_swizzle            = common_swizzle,
 219 };
 220 ALIAS_MV(rx164)