1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/arch/alpha/kernel/sys_eiger.c 4 * 5 * Copyright (C) 1995 David A Rusling 6 * Copyright (C) 1996, 1999 Jay A Estabrook 7 * Copyright (C) 1998, 1999 Richard Henderson 8 * Copyright (C) 1999 Iain Grant 9 * 10 * Code supporting the EIGER (EV6+TSUNAMI). 11 */ 12 13 #include <linux/kernel.h> 14 #include <linux/types.h> 15 #include <linux/mm.h> 16 #include <linux/sched.h> 17 #include <linux/pci.h> 18 #include <linux/init.h> 19 #include <linux/bitops.h> 20 21 #include <asm/ptrace.h> 22 #include <asm/dma.h> 23 #include <asm/irq.h> 24 #include <asm/mmu_context.h> 25 #include <asm/io.h> 26 #include <asm/pgtable.h> 27 #include <asm/core_tsunami.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 that this interrupt code is identical to TAKARA. */ 38 39 /* Note mask bit is true for DISABLED irqs. */ 40 static unsigned long cached_irq_mask[2] = { -1, -1 }; 41 42 static inline void 43 eiger_update_irq_hw(unsigned long irq, unsigned long mask) 44 { 45 int regaddr; 46 47 mask = (irq >= 64 ? mask << 16 : mask >> ((irq - 16) & 0x30)); 48 regaddr = 0x510 + (((irq - 16) >> 2) & 0x0c); 49 outl(mask & 0xffff0000UL, regaddr); 50 } 51 52 static inline void 53 eiger_enable_irq(struct irq_data *d) 54 { 55 unsigned int irq = d->irq; 56 unsigned long mask; 57 mask = (cached_irq_mask[irq >= 64] &= ~(1UL << (irq & 63))); 58 eiger_update_irq_hw(irq, mask); 59 } 60 61 static void 62 eiger_disable_irq(struct irq_data *d) 63 { 64 unsigned int irq = d->irq; 65 unsigned long mask; 66 mask = (cached_irq_mask[irq >= 64] |= 1UL << (irq & 63)); 67 eiger_update_irq_hw(irq, mask); 68 } 69 70 static struct irq_chip eiger_irq_type = { 71 .name = "EIGER", 72 .irq_unmask = eiger_enable_irq, 73 .irq_mask = eiger_disable_irq, 74 .irq_mask_ack = eiger_disable_irq, 75 }; 76 77 static void 78 eiger_device_interrupt(unsigned long vector) 79 { 80 unsigned intstatus; 81 82 /* 83 * The PALcode will have passed us vectors 0x800 or 0x810, 84 * which are fairly arbitrary values and serve only to tell 85 * us whether an interrupt has come in on IRQ0 or IRQ1. If 86 * it's IRQ1 it's a PCI interrupt; if it's IRQ0, it's 87 * probably ISA, but PCI interrupts can come through IRQ0 88 * as well if the interrupt controller isn't in accelerated 89 * mode. 90 * 91 * OTOH, the accelerator thing doesn't seem to be working 92 * overly well, so what we'll do instead is try directly 93 * examining the Master Interrupt Register to see if it's a 94 * PCI interrupt, and if _not_ then we'll pass it on to the 95 * ISA handler. 96 */ 97 98 intstatus = inw(0x500) & 15; 99 if (intstatus) { 100 /* 101 * This is a PCI interrupt. Check each bit and 102 * despatch an interrupt if it's set. 103 */ 104 105 if (intstatus & 8) handle_irq(16+3); 106 if (intstatus & 4) handle_irq(16+2); 107 if (intstatus & 2) handle_irq(16+1); 108 if (intstatus & 1) handle_irq(16+0); 109 } else { 110 isa_device_interrupt(vector); 111 } 112 } 113 114 static void 115 eiger_srm_device_interrupt(unsigned long vector) 116 { 117 int irq = (vector - 0x800) >> 4; 118 handle_irq(irq); 119 } 120 121 static void __init 122 eiger_init_irq(void) 123 { 124 long i; 125 126 outb(0, DMA1_RESET_REG); 127 outb(0, DMA2_RESET_REG); 128 outb(DMA_MODE_CASCADE, DMA2_MODE_REG); 129 outb(0, DMA2_MASK_REG); 130 131 if (alpha_using_srm) 132 alpha_mv.device_interrupt = eiger_srm_device_interrupt; 133 134 for (i = 16; i < 128; i += 16) 135 eiger_update_irq_hw(i, -1); 136 137 init_i8259a_irqs(); 138 139 for (i = 16; i < 128; ++i) { 140 irq_set_chip_and_handler(i, &eiger_irq_type, handle_level_irq); 141 irq_set_status_flags(i, IRQ_LEVEL); 142 } 143 } 144 145 static int 146 eiger_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) 147 { 148 u8 irq_orig; 149 150 /* The SRM console has already calculated out the IRQ value's for 151 option cards. As this works lets just read in the value already 152 set and change it to a useable value by Linux. 153 154 All the IRQ values generated by the console are greater than 90, 155 so we subtract 80 because it is (90 - allocated ISA IRQ's). */ 156 157 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq_orig); 158 159 return irq_orig - 0x80; 160 } 161 162 static u8 163 eiger_swizzle(struct pci_dev *dev, u8 *pinp) 164 { 165 struct pci_controller *hose = dev->sysdata; 166 int slot, pin = *pinp; 167 int bridge_count = 0; 168 169 /* Find the number of backplane bridges. */ 170 int backplane = inw(0x502) & 0x0f; 171 172 switch (backplane) 173 { 174 case 0x00: bridge_count = 0; break; /* No bridges */ 175 case 0x01: bridge_count = 1; break; /* 1 */ 176 case 0x03: bridge_count = 2; break; /* 2 */ 177 case 0x07: bridge_count = 3; break; /* 3 */ 178 case 0x0f: bridge_count = 4; break; /* 4 */ 179 }; 180 181 slot = PCI_SLOT(dev->devfn); 182 while (dev->bus->self) { 183 /* Check for built-in bridges on hose 0. */ 184 if (hose->index == 0 185 && (PCI_SLOT(dev->bus->self->devfn) 186 > 20 - bridge_count)) { 187 slot = PCI_SLOT(dev->devfn); 188 break; 189 } 190 /* Must be a card-based bridge. */ 191 pin = pci_swizzle_interrupt_pin(dev, pin); 192 193 /* Move up the chain of bridges. */ 194 dev = dev->bus->self; 195 } 196 *pinp = pin; 197 return slot; 198 } 199 200 /* 201 * The System Vectors 202 */ 203 204 struct alpha_machine_vector eiger_mv __initmv = { 205 .vector_name = "Eiger", 206 DO_EV6_MMU, 207 DO_DEFAULT_RTC, 208 DO_TSUNAMI_IO, 209 .machine_check = tsunami_machine_check, 210 .max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS, 211 .min_io_address = DEFAULT_IO_BASE, 212 .min_mem_address = DEFAULT_MEM_BASE, 213 .pci_dac_offset = TSUNAMI_DAC_OFFSET, 214 215 .nr_irqs = 128, 216 .device_interrupt = eiger_device_interrupt, 217 218 .init_arch = tsunami_init_arch, 219 .init_irq = eiger_init_irq, 220 .init_rtc = common_init_rtc, 221 .init_pci = common_init_pci, 222 .kill_arch = tsunami_kill_arch, 223 .pci_map_irq = eiger_map_irq, 224 .pci_swizzle = eiger_swizzle, 225 }; 226 ALIAS_MV(eiger) 227