arch/alpha/kernel/sys_jensen.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *      linux/arch/alpha/kernel/sys_jensen.c
   4  *
   5  *      Copyright (C) 1995 Linus Torvalds
   6  *      Copyright (C) 1998, 1999 Richard Henderson
   7  *
   8  * Code supporting the Jensen.
   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
  18 #include <asm/ptrace.h>
  19
  20 #define __EXTERN_INLINE inline
  21 #include <asm/io.h>
  22 #include <asm/jensen.h>
  23 #undef  __EXTERN_INLINE
  24
  25 #include <asm/dma.h>
  26 #include <asm/irq.h>
  27 #include <asm/mmu_context.h>
  28 #include <asm/pgtable.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 /*
  38  * Jensen is special: the vector is 0x8X0 for EISA interrupt X, and
  39  * 0x9X0 for the local motherboard interrupts.
  40  *
  41  * Note especially that those local interrupts CANNOT be masked,
  42  * which causes much of the pain below...
  43  *
  44  *      0x660 - NMI
  45  *
  46  *      0x800 - IRQ0  interval timer (not used, as we use the RTC timer)
  47  *      0x810 - IRQ1  line printer (duh..)
  48  *      0x860 - IRQ6  floppy disk
  49  *
  50  *      0x900 - COM1
  51  *      0x920 - COM2
  52  *      0x980 - keyboard
  53  *      0x990 - mouse
  54  *
  55  * PCI-based systems are more sane: they don't have the local
  56  * interrupts at all, and have only normal PCI interrupts from
  57  * devices.  Happily it's easy enough to do a sane mapping from the
  58  * Jensen.
  59  *
  60  * Note that this means that we may have to do a hardware
  61  * "local_op" to a different interrupt than we report to the rest of the
  62  * world.
  63  */
  64
  65 static void
  66 jensen_local_enable(struct irq_data *d)
  67 {
  68         /* the parport is really hw IRQ 1, silly Jensen.  */
  69         if (d->irq == 7)
  70                 i8259a_enable_irq(d);
  71 }
  72
  73 static void
  74 jensen_local_disable(struct irq_data *d)
  75 {
  76         /* the parport is really hw IRQ 1, silly Jensen.  */
  77         if (d->irq == 7)
  78                 i8259a_disable_irq(d);
  79 }
  80
  81 static void
  82 jensen_local_mask_ack(struct irq_data *d)
  83 {
  84         /* the parport is really hw IRQ 1, silly Jensen.  */
  85         if (d->irq == 7)
  86                 i8259a_mask_and_ack_irq(d);
  87 }
  88
  89 static struct irq_chip jensen_local_irq_type = {
  90         .name           = "LOCAL",
  91         .irq_unmask     = jensen_local_enable,
  92         .irq_mask       = jensen_local_disable,
  93         .irq_mask_ack   = jensen_local_mask_ack,
  94 };
  95
  96 static void
  97 jensen_device_interrupt(unsigned long vector)
  98 {
  99         int irq;
 100
 101         switch (vector) {
 102         case 0x660:
 103                 printk("Whee.. NMI received. Probable hardware error\n");
 104                 printk("61=%02x, 461=%02x\n", inb(0x61), inb(0x461));
 105                 return;
 106
 107         /* local device interrupts: */
 108         case 0x900: irq = 4; break;             /* com1 -> irq 4 */
 109         case 0x920: irq = 3; break;             /* com2 -> irq 3 */
 110         case 0x980: irq = 1; break;             /* kbd -> irq 1 */
 111         case 0x990: irq = 9; break;             /* mouse -> irq 9 */
 112
 113         default:
 114                 if (vector > 0x900) {
 115                         printk("Unknown local interrupt %lx\n", vector);
 116                         return;
 117                 }
 118
 119                 irq = (vector - 0x800) >> 4;
 120                 if (irq == 1)
 121                         irq = 7;
 122                 break;
 123         }
 124
 125         /* If there is no handler yet... */
 126         if (!irq_has_action(irq)) {
 127             /* If it is a local interrupt that cannot be masked... */
 128             if (vector >= 0x900)
 129             {
 130                 /* Clear keyboard/mouse state */
 131                 inb(0x64);
 132                 inb(0x60);
 133                 /* Reset serial ports */
 134                 inb(0x3fa);
 135                 inb(0x2fa);
 136                 outb(0x0c, 0x3fc);
 137                 outb(0x0c, 0x2fc);
 138                 /* Clear NMI */
 139                 outb(0,0x61);
 140                 outb(0,0x461);
 141             }
 142         }
 143
 144 #if 0
 145         /* A useful bit of code to find out if an interrupt is going wild.  */
 146         {
 147           static unsigned int last_msg = 0, last_cc = 0;
 148           static int last_irq = -1, count = 0;
 149           unsigned int cc;
 150
 151           __asm __volatile("rpcc %0" : "=r"(cc));
 152           ++count;
 153 #define JENSEN_CYCLES_PER_SEC   (150000000)
 154           if (cc - last_msg > ((JENSEN_CYCLES_PER_SEC) * 3) ||
 155               irq != last_irq) {
 156                 printk(KERN_CRIT " irq %d count %d cc %u @ %lx\n",
 157                        irq, count, cc-last_cc, get_irq_regs()->pc);
 158                 count = 0;
 159                 last_msg = cc;
 160                 last_irq = irq;
 161           }
 162           last_cc = cc;
 163         }
 164 #endif
 165
 166         handle_irq(irq);
 167 }
 168
 169 static void __init
 170 jensen_init_irq(void)
 171 {
 172         init_i8259a_irqs();
 173
 174         irq_set_chip_and_handler(1, &jensen_local_irq_type, handle_level_irq);
 175         irq_set_chip_and_handler(4, &jensen_local_irq_type, handle_level_irq);
 176         irq_set_chip_and_handler(3, &jensen_local_irq_type, handle_level_irq);
 177         irq_set_chip_and_handler(7, &jensen_local_irq_type, handle_level_irq);
 178         irq_set_chip_and_handler(9, &jensen_local_irq_type, handle_level_irq);
 179
 180         common_init_isa_dma();
 181 }
 182
 183 static void __init
 184 jensen_init_arch(void)
 185 {
 186         struct pci_controller *hose;
 187 #ifdef CONFIG_PCI
 188         static struct pci_dev fake_isa_bridge = { .dma_mask = 0xffffffffUL, };
 189
 190         isa_bridge = &fake_isa_bridge;
 191 #endif
 192
 193         /* Create a hose so that we can report i/o base addresses to
 194            userland.  */
 195
 196         pci_isa_hose = hose = alloc_pci_controller();
 197         hose->io_space = &ioport_resource;
 198         hose->mem_space = &iomem_resource;
 199         hose->index = 0;
 200
 201         hose->sparse_mem_base = EISA_MEM - IDENT_ADDR;
 202         hose->dense_mem_base = 0;
 203         hose->sparse_io_base = EISA_IO - IDENT_ADDR;
 204         hose->dense_io_base = 0;
 205
 206         hose->sg_isa = hose->sg_pci = NULL;
 207         __direct_map_base = 0;
 208         __direct_map_size = 0xffffffff;
 209 }
 210
 211 static void
 212 jensen_machine_check(unsigned long vector, unsigned long la)
 213 {
 214         printk(KERN_CRIT "Machine check\n");
 215 }
 216
 217 /*
 218  * The System Vector
 219  */
 220
 221 struct alpha_machine_vector jensen_mv __initmv = {
 222         .vector_name            = "Jensen",
 223         DO_EV4_MMU,
 224         IO_LITE(JENSEN,jensen),
 225         .machine_check          = jensen_machine_check,
 226         .max_isa_dma_address    = ALPHA_MAX_ISA_DMA_ADDRESS,
 227         .rtc_port               = 0x170,
 228
 229         .nr_irqs                = 16,
 230         .device_interrupt       = jensen_device_interrupt,
 231
 232         .init_arch              = jensen_init_arch,
 233         .init_irq               = jensen_init_irq,
 234         .init_rtc               = common_init_rtc,
 235         .init_pci               = NULL,
 236         .kill_arch              = NULL,
 237 };
 238 ALIAS_MV(jensen)