arch/alpha/kernel/sys_takara.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *      linux/arch/alpha/kernel/sys_takara.c
   4  *
   5  *      Copyright (C) 1995 David A Rusling
   6  *      Copyright (C) 1996 Jay A Estabrook
   7  *      Copyright (C) 1998, 1999 Richard Henderson
   8  *
   9  * Code supporting the TAKARA.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/types.h>
  14 #include <linux/mm.h>
  15 #include <linux/sched.h>
  16 #include <linux/pci.h>
  17 #include <linux/init.h>
  18
  19 #include <asm/ptrace.h>
  20 #include <asm/dma.h>
  21 #include <asm/irq.h>
  22 #include <asm/mmu_context.h>
  23 #include <asm/io.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/core_cia.h>
  26 #include <asm/tlbflush.h>
  27
  28 #include "proto.h"
  29 #include "irq_impl.h"
  30 #include "pci_impl.h"
  31 #include "machvec_impl.h"
  32 #include "pc873xx.h"
  33
  34 /* Note mask bit is true for DISABLED irqs.  */
  35 static unsigned long cached_irq_mask[2] = { -1, -1 };
  36
  37 static inline void
  38 takara_update_irq_hw(unsigned long irq, unsigned long mask)
  39 {
  40         int regaddr;
  41
  42         mask = (irq >= 64 ? mask << 16 : mask >> ((irq - 16) & 0x30));
  43         regaddr = 0x510 + (((irq - 16) >> 2) & 0x0c);
  44         outl(mask & 0xffff0000UL, regaddr);
  45 }
  46
  47 static inline void
  48 takara_enable_irq(struct irq_data *d)
  49 {
  50         unsigned int irq = d->irq;
  51         unsigned long mask;
  52         mask = (cached_irq_mask[irq >= 64] &= ~(1UL << (irq & 63)));
  53         takara_update_irq_hw(irq, mask);
  54 }
  55
  56 static void
  57 takara_disable_irq(struct irq_data *d)
  58 {
  59         unsigned int irq = d->irq;
  60         unsigned long mask;
  61         mask = (cached_irq_mask[irq >= 64] |= 1UL << (irq & 63));
  62         takara_update_irq_hw(irq, mask);
  63 }
  64
  65 static struct irq_chip takara_irq_type = {
  66         .name           = "TAKARA",
  67         .irq_unmask     = takara_enable_irq,
  68         .irq_mask       = takara_disable_irq,
  69         .irq_mask_ack   = takara_disable_irq,
  70 };
  71
  72 static void
  73 takara_device_interrupt(unsigned long vector)
  74 {
  75         unsigned intstatus;
  76
  77         /*
  78          * The PALcode will have passed us vectors 0x800 or 0x810,
  79          * which are fairly arbitrary values and serve only to tell
  80          * us whether an interrupt has come in on IRQ0 or IRQ1. If
  81          * it's IRQ1 it's a PCI interrupt; if it's IRQ0, it's
  82          * probably ISA, but PCI interrupts can come through IRQ0
  83          * as well if the interrupt controller isn't in accelerated
  84          * mode.
  85          *
  86          * OTOH, the accelerator thing doesn't seem to be working
  87          * overly well, so what we'll do instead is try directly
  88          * examining the Master Interrupt Register to see if it's a
  89          * PCI interrupt, and if _not_ then we'll pass it on to the
  90          * ISA handler.
  91          */
  92
  93         intstatus = inw(0x500) & 15;
  94         if (intstatus) {
  95                 /*
  96                  * This is a PCI interrupt. Check each bit and
  97                  * despatch an interrupt if it's set.
  98                  */
  99
 100                 if (intstatus & 8) handle_irq(16+3);
 101                 if (intstatus & 4) handle_irq(16+2);
 102                 if (intstatus & 2) handle_irq(16+1);
 103                 if (intstatus & 1) handle_irq(16+0);
 104         } else {
 105                 isa_device_interrupt (vector);
 106         }
 107 }
 108
 109 static void
 110 takara_srm_device_interrupt(unsigned long vector)
 111 {
 112         int irq = (vector - 0x800) >> 4;
 113         handle_irq(irq);
 114 }
 115
 116 static void __init
 117 takara_init_irq(void)
 118 {
 119         long i;
 120
 121         init_i8259a_irqs();
 122
 123         if (alpha_using_srm) {
 124                 alpha_mv.device_interrupt = takara_srm_device_interrupt;
 125         } else {
 126                 unsigned int ctlreg = inl(0x500);
 127
 128                 /* Return to non-accelerated mode.  */
 129                 ctlreg &= ~0x8000;
 130                 outl(ctlreg, 0x500);
 131
 132                 /* Enable the PCI interrupt register.  */
 133                 ctlreg = 0x05107c00;
 134                 outl(ctlreg, 0x500);
 135         }
 136
 137         for (i = 16; i < 128; i += 16)
 138                 takara_update_irq_hw(i, -1);
 139
 140         for (i = 16; i < 128; ++i) {
 141                 irq_set_chip_and_handler(i, &takara_irq_type,
 142                                          handle_level_irq);
 143                 irq_set_status_flags(i, IRQ_LEVEL);
 144         }
 145
 146         common_init_isa_dma();
 147 }
 148
 149
 150 /*
 151  * The Takara has PCI devices 1, 2, and 3 configured to slots 20,
 152  * 19, and 18 respectively, in the default configuration. They can
 153  * also be jumpered to slots 8, 7, and 6 respectively, which is fun
 154  * because the SIO ISA bridge can also be slot 7. However, the SIO
 155  * doesn't explicitly generate PCI-type interrupts, so we can
 156  * assign it whatever the hell IRQ we like and it doesn't matter.
 157  */
 158
 159 static int
 160 takara_map_irq_srm(const struct pci_dev *dev, u8 slot, u8 pin)
 161 {
 162         static char irq_tab[15][5] = {
 163                 { 16+3, 16+3, 16+3, 16+3, 16+3},   /* slot  6 == device 3 */
 164                 { 16+2, 16+2, 16+2, 16+2, 16+2},   /* slot  7 == device 2 */
 165                 { 16+1, 16+1, 16+1, 16+1, 16+1},   /* slot  8 == device 1 */
 166                 {   -1,   -1,   -1,   -1,   -1},   /* slot  9 == nothing */
 167                 {   -1,   -1,   -1,   -1,   -1},   /* slot 10 == nothing */
 168                 {   -1,   -1,   -1,   -1,   -1},   /* slot 11 == nothing */
 169                 /* These are behind the bridges.  */
 170                 {   12,   12,   13,   14,   15},   /* slot 12 == nothing */
 171                 {    8,    8,    9,   19,   11},   /* slot 13 == nothing */
 172                 {    4,    4,    5,    6,    7},   /* slot 14 == nothing */
 173                 {    0,    0,    1,    2,    3},   /* slot 15 == nothing */
 174                 {   -1,   -1,   -1,   -1,   -1},   /* slot 16 == nothing */
 175                 {64+ 0, 64+0, 64+1, 64+2, 64+3},   /* slot 17= device 4 */
 176                 {48+ 0, 48+0, 48+1, 48+2, 48+3},   /* slot 18= device 3 */
 177                 {32+ 0, 32+0, 32+1, 32+2, 32+3},   /* slot 19= device 2 */
 178                 {16+ 0, 16+0, 16+1, 16+2, 16+3},   /* slot 20= device 1 */
 179         };
 180         const long min_idsel = 6, max_idsel = 20, irqs_per_slot = 5;
 181         int irq = COMMON_TABLE_LOOKUP;
 182         if (irq >= 0 && irq < 16) {
 183                 /* Guess that we are behind a bridge.  */
 184                 unsigned int busslot = PCI_SLOT(dev->bus->self->devfn);
 185                 irq += irq_tab[busslot-min_idsel][0];
 186         }
 187         return irq;
 188 }
 189
 190 static int __init
 191 takara_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
 192 {
 193         static char irq_tab[15][5] __initdata = {
 194                 { 16+3, 16+3, 16+3, 16+3, 16+3},   /* slot  6 == device 3 */
 195                 { 16+2, 16+2, 16+2, 16+2, 16+2},   /* slot  7 == device 2 */
 196                 { 16+1, 16+1, 16+1, 16+1, 16+1},   /* slot  8 == device 1 */
 197                 {   -1,   -1,   -1,   -1,   -1},   /* slot  9 == nothing */
 198                 {   -1,   -1,   -1,   -1,   -1},   /* slot 10 == nothing */
 199                 {   -1,   -1,   -1,   -1,   -1},   /* slot 11 == nothing */
 200                 {   -1,   -1,   -1,   -1,   -1},   /* slot 12 == nothing */
 201                 {   -1,   -1,   -1,   -1,   -1},   /* slot 13 == nothing */
 202                 {   -1,   -1,   -1,   -1,   -1},   /* slot 14 == nothing */
 203                 {   -1,   -1,   -1,   -1,   -1},   /* slot 15 == nothing */
 204                 {   -1,   -1,   -1,   -1,   -1},   /* slot 16 == nothing */
 205                 {   -1,   -1,   -1,   -1,   -1},   /* slot 17 == nothing */
 206                 { 16+3, 16+3, 16+3, 16+3, 16+3},   /* slot 18 == device 3 */
 207                 { 16+2, 16+2, 16+2, 16+2, 16+2},   /* slot 19 == device 2 */
 208                 { 16+1, 16+1, 16+1, 16+1, 16+1},   /* slot 20 == device 1 */
 209         };
 210         const long min_idsel = 6, max_idsel = 20, irqs_per_slot = 5;
 211         return COMMON_TABLE_LOOKUP;
 212 }
 213
 214 static u8
 215 takara_swizzle(struct pci_dev *dev, u8 *pinp)
 216 {
 217         int slot = PCI_SLOT(dev->devfn);
 218         int pin = *pinp;
 219         unsigned int ctlreg = inl(0x500);
 220         unsigned int busslot;
 221
 222         if (!dev->bus->self)
 223                 return slot;
 224
 225         busslot = PCI_SLOT(dev->bus->self->devfn);
 226         /* Check for built-in bridges.  */
 227         if (dev->bus->number != 0
 228             && busslot > 16
 229             && ((1<<(36-busslot)) & ctlreg)) {
 230                 if (pin == 1)
 231                         pin += (20 - busslot);
 232                 else {
 233                         printk(KERN_WARNING "takara_swizzle: can only "
 234                                "handle cards with INTA IRQ pin.\n");
 235                 }
 236         } else {
 237                 /* Must be a card-based bridge.  */
 238                 printk(KERN_WARNING "takara_swizzle: cannot handle "
 239                        "card-bridge behind builtin bridge yet.\n");
 240         }
 241
 242         *pinp = pin;
 243         return slot;
 244 }
 245
 246 static void __init
 247 takara_init_pci(void)
 248 {
 249         if (alpha_using_srm)
 250                 alpha_mv.pci_map_irq = takara_map_irq_srm;
 251
 252         cia_init_pci();
 253
 254         if (pc873xx_probe() == -1) {
 255                 printk(KERN_ERR "Probing for PC873xx Super IO chip failed.\n");
 256         } else {
 257                 printk(KERN_INFO "Found %s Super IO chip at 0x%x\n",
 258                         pc873xx_get_model(), pc873xx_get_base());
 259                 pc873xx_enable_ide();
 260         }
 261 }
 262
 263
 264 /*
 265  * The System Vector
 266  */
 267
 268 struct alpha_machine_vector takara_mv __initmv = {
 269         .vector_name            = "Takara",
 270         DO_EV5_MMU,
 271         DO_DEFAULT_RTC,
 272         DO_CIA_IO,
 273         .machine_check          = cia_machine_check,
 274         .max_isa_dma_address    = ALPHA_MAX_ISA_DMA_ADDRESS,
 275         .min_io_address         = DEFAULT_IO_BASE,
 276         .min_mem_address        = CIA_DEFAULT_MEM_BASE,
 277
 278         .nr_irqs                = 128,
 279         .device_interrupt       = takara_device_interrupt,
 280
 281         .init_arch              = cia_init_arch,
 282         .init_irq               = takara_init_irq,
 283         .init_rtc               = common_init_rtc,
 284         .init_pci               = takara_init_pci,
 285         .kill_arch              = cia_kill_arch,
 286         .pci_map_irq            = takara_map_irq,
 287         .pci_swizzle            = takara_swizzle,
 288 };
 289 ALIAS_MV(takara)