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Diffstat (limited to 'arch/alpha/kernel/sys_eiger.c')
| -rw-r--r-- | arch/alpha/kernel/sys_eiger.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/arch/alpha/kernel/sys_eiger.c b/arch/alpha/kernel/sys_eiger.c new file mode 100644 index 0000000000..aea8a54da4 --- /dev/null +++ b/arch/alpha/kernel/sys_eiger.c @@ -0,0 +1,225 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * linux/arch/alpha/kernel/sys_eiger.c + * + * Copyright (C) 1995 David A Rusling + * Copyright (C) 1996, 1999 Jay A Estabrook + * Copyright (C) 1998, 1999 Richard Henderson + * Copyright (C) 1999 Iain Grant + * + * Code supporting the EIGER (EV6+TSUNAMI). + */ + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/pci.h> +#include <linux/init.h> +#include <linux/bitops.h> + +#include <asm/ptrace.h> +#include <asm/dma.h> +#include <asm/irq.h> +#include <asm/mmu_context.h> +#include <asm/io.h> +#include <asm/core_tsunami.h> +#include <asm/hwrpb.h> +#include <asm/tlbflush.h> + +#include "proto.h" +#include "irq_impl.h" +#include "pci_impl.h" +#include "machvec_impl.h" + + +/* Note that this interrupt code is identical to TAKARA. */ + +/* Note mask bit is true for DISABLED irqs. */ +static unsigned long cached_irq_mask[2] = { -1, -1 }; + +static inline void +eiger_update_irq_hw(unsigned long irq, unsigned long mask) +{ + int regaddr; + + mask = (irq >= 64 ? mask << 16 : mask >> ((irq - 16) & 0x30)); + regaddr = 0x510 + (((irq - 16) >> 2) & 0x0c); + outl(mask & 0xffff0000UL, regaddr); +} + +static inline void +eiger_enable_irq(struct irq_data *d) +{ + unsigned int irq = d->irq; + unsigned long mask; + mask = (cached_irq_mask[irq >= 64] &= ~(1UL << (irq & 63))); + eiger_update_irq_hw(irq, mask); +} + +static void +eiger_disable_irq(struct irq_data *d) +{ + unsigned int irq = d->irq; + unsigned long mask; + mask = (cached_irq_mask[irq >= 64] |= 1UL << (irq & 63)); + eiger_update_irq_hw(irq, mask); +} + +static struct irq_chip eiger_irq_type = { + .name = "EIGER", + .irq_unmask = eiger_enable_irq, + .irq_mask = eiger_disable_irq, + .irq_mask_ack = eiger_disable_irq, +}; + +static void +eiger_device_interrupt(unsigned long vector) +{ + unsigned intstatus; + + /* + * The PALcode will have passed us vectors 0x800 or 0x810, + * which are fairly arbitrary values and serve only to tell + * us whether an interrupt has come in on IRQ0 or IRQ1. If + * it's IRQ1 it's a PCI interrupt; if it's IRQ0, it's + * probably ISA, but PCI interrupts can come through IRQ0 + * as well if the interrupt controller isn't in accelerated + * mode. + * + * OTOH, the accelerator thing doesn't seem to be working + * overly well, so what we'll do instead is try directly + * examining the Master Interrupt Register to see if it's a + * PCI interrupt, and if _not_ then we'll pass it on to the + * ISA handler. + */ + + intstatus = inw(0x500) & 15; + if (intstatus) { + /* + * This is a PCI interrupt. Check each bit and + * despatch an interrupt if it's set. + */ + + if (intstatus & 8) handle_irq(16+3); + if (intstatus & 4) handle_irq(16+2); + if (intstatus & 2) handle_irq(16+1); + if (intstatus & 1) handle_irq(16+0); + } else { + isa_device_interrupt(vector); + } +} + +static void +eiger_srm_device_interrupt(unsigned long vector) +{ + int irq = (vector - 0x800) >> 4; + handle_irq(irq); +} + +static void __init +eiger_init_irq(void) +{ + long i; + + outb(0, DMA1_RESET_REG); + outb(0, DMA2_RESET_REG); + outb(DMA_MODE_CASCADE, DMA2_MODE_REG); + outb(0, DMA2_MASK_REG); + + if (alpha_using_srm) + alpha_mv.device_interrupt = eiger_srm_device_interrupt; + + for (i = 16; i < 128; i += 16) + eiger_update_irq_hw(i, -1); + + init_i8259a_irqs(); + + for (i = 16; i < 128; ++i) { + irq_set_chip_and_handler(i, &eiger_irq_type, handle_level_irq); + irq_set_status_flags(i, IRQ_LEVEL); + } +} + +static int +eiger_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) +{ + u8 irq_orig; + + /* The SRM console has already calculated out the IRQ value's for + option cards. As this works lets just read in the value already + set and change it to a useable value by Linux. + + All the IRQ values generated by the console are greater than 90, + so we subtract 80 because it is (90 - allocated ISA IRQ's). */ + + pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq_orig); + + return irq_orig - 0x80; +} + +static u8 +eiger_swizzle(struct pci_dev *dev, u8 *pinp) +{ + struct pci_controller *hose = dev->sysdata; + int slot, pin = *pinp; + int bridge_count = 0; + + /* Find the number of backplane bridges. */ + int backplane = inw(0x502) & 0x0f; + + switch (backplane) + { + case 0x00: bridge_count = 0; break; /* No bridges */ + case 0x01: bridge_count = 1; break; /* 1 */ + case 0x03: bridge_count = 2; break; /* 2 */ + case 0x07: bridge_count = 3; break; /* 3 */ + case 0x0f: bridge_count = 4; break; /* 4 */ + } + + slot = PCI_SLOT(dev->devfn); + while (dev->bus->self) { + /* Check for built-in bridges on hose 0. */ + if (hose->index == 0 + && (PCI_SLOT(dev->bus->self->devfn) + > 20 - bridge_count)) { + slot = PCI_SLOT(dev->devfn); + break; + } + /* Must be a card-based bridge. */ + pin = pci_swizzle_interrupt_pin(dev, pin); + + /* Move up the chain of bridges. */ + dev = dev->bus->self; + } + *pinp = pin; + return slot; +} + +/* + * The System Vectors + */ + +struct alpha_machine_vector eiger_mv __initmv = { + .vector_name = "Eiger", + DO_EV6_MMU, + DO_DEFAULT_RTC, + DO_TSUNAMI_IO, + .machine_check = tsunami_machine_check, + .max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS, + .min_io_address = DEFAULT_IO_BASE, + .min_mem_address = DEFAULT_MEM_BASE, + .pci_dac_offset = TSUNAMI_DAC_OFFSET, + + .nr_irqs = 128, + .device_interrupt = eiger_device_interrupt, + + .init_arch = tsunami_init_arch, + .init_irq = eiger_init_irq, + .init_rtc = common_init_rtc, + .init_pci = common_init_pci, + .kill_arch = tsunami_kill_arch, + .pci_map_irq = eiger_map_irq, + .pci_swizzle = eiger_swizzle, +}; +ALIAS_MV(eiger) |