// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/alpha/kernel/sys_alcor.c
*
* Copyright (C) 1995 David A Rusling
* Copyright (C) 1996 Jay A Estabrook
* Copyright (C) 1998, 1999 Richard Henderson
*
* Code supporting the ALCOR and XLT (XL-300/366/433).
*/
#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/reboot.h>
#include <linux/bitops.h>
#include <asm/ptrace.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <asm/mmu_context.h>
#include <asm/irq.h>
#include <asm/core_cia.h>
#include <asm/tlbflush.h>
#include "proto.h"
#include "irq_impl.h"
#include "pci_impl.h"
#include "machvec_impl.h"
/* Note mask bit is true for ENABLED irqs. */
static unsigned long cached_irq_mask;
static inline void
alcor_update_irq_hw(unsigned long mask)
{
*(vuip)GRU_INT_MASK = mask;
mb();
}
static inline void
alcor_enable_irq(struct irq_data *d)
{
alcor_update_irq_hw(cached_irq_mask |= 1UL << (d->irq - 16));
}
static void
alcor_disable_irq(struct irq_data *d)
{
alcor_update_irq_hw(cached_irq_mask &= ~(1UL << (d->irq - 16)));
}
static void
alcor_mask_and_ack_irq(struct irq_data *d)
{
alcor_disable_irq(d);
/* On ALCOR/XLT, need to dismiss interrupt via GRU. */
*(vuip)GRU_INT_CLEAR = 1 << (d->irq - 16); mb();
*(vuip)GRU_INT_CLEAR = 0; mb();
}
static void
alcor_isa_mask_and_ack_irq(struct irq_data *d)
{
i8259a_mask_and_ack_irq(d);
/* On ALCOR/XLT, need to dismiss interrupt via GRU. */
*(vuip)GRU_INT_CLEAR = 0x80000000; mb();
*(vuip)GRU_INT_CLEAR = 0; mb();
}
static struct irq_chip alcor_irq_type = {
.name = "ALCOR",
.irq_unmask = alcor_enable_irq,
.irq_mask = alcor_disable_irq,
.irq_mask_ack = alcor_mask_and_ack_irq,
};
static void
alcor_device_interrupt(unsigned long vector)
{
unsigned long pld;
unsigned int i;
/* Read the interrupt summary register of the GRU */
pld = (*(vuip)GRU_INT_REQ) & GRU_INT_REQ_BITS;
/*
* Now for every possible bit set, work through them and call
* the appropriate interrupt handler.
*/
while (pld) {
i = ffz(~pld);
pld &= pld - 1; /* clear least bit set */
if (i == 31) {
isa_device_interrupt(vector);
} else {
handle_irq(16 + i);
}
}
}
static void __init
alcor_init_irq(void)
{
long i;
if (alpha_using_srm)
alpha_mv.device_interrupt = srm_device_interrupt;
*(vuip)GRU_INT_MASK = 0; mb(); /* all disabled */
*(vuip)GRU_INT_EDGE = 0; mb(); /* all are level */
*(vuip)GRU_INT_HILO = 0x80000000U; mb(); /* ISA only HI */
*(vuip)GRU_INT_CLEAR = 0; mb(); /* all clear */
for (i = 16; i < 48; ++i) {
/* On Alcor, at least, lines 20..30 are not connected
and can generate spurious interrupts if we turn them
on while IRQ probing. */
if (i >= 16+20 && i <= 16+30)
continue;
irq_set_chip_and_handler(i, &alcor_irq_type, handle_level_irq);
irq_set_status_flags(i, IRQ_LEVEL);
}
i8259a_irq_type.irq_ack = alcor_isa_mask_and_ack_irq;
init_i8259a_irqs();
common_init_isa_dma();
if (request_irq(16 + 31, no_action, 0, "isa-cascade", NULL))
pr_err("Failed to register isa-cascade interrupt\n");
}
/*
* PCI Fixup configuration.
*
* Summary @ GRU_INT_REQ:
* Bit Meaning
* 0 Interrupt Line A from slot 2
* 1 Interrupt Line B from slot 2
* 2 Interrupt Line C from slot 2
* 3 Interrupt Line D from slot 2
* 4 Interrupt Line A from slot 1
* 5 Interrupt line B from slot 1
* 6 Interrupt Line C from slot 1
* 7 Interrupt Line D from slot 1
* 8 Interrupt Line A from slot 0
* 9 Interrupt Line B from slot 0
*10 Interrupt Line C from slot 0
*11 Interrupt Line D from slot 0
*12 Interrupt Line A from slot 4
*13 Interrupt Line B from slot 4
*14 Interrupt Line C from slot 4
*15 Interrupt Line D from slot 4
*16 Interrupt Line D from slot 3
*17 Interrupt Line D from slot 3
*18 Interrupt Line D from slot 3
*19 Interrupt Line D from slot 3
*20-30 Reserved
*31 EISA interrupt
*
* The device to slot mapping looks like:
*
* Slot Device
* 6 built-in TULIP (XLT only)
* 7 PCI on board slot 0
* 8 PCI on board slot 3
* 9 PCI on board slot 4
* 10 PCEB (PCI-EISA bridge)
* 11 PCI on board slot 2
* 12 PCI on board slot 1
*
*
* This two layered interrupt approach means that we allocate IRQ 16 and
* above for PCI interrupts. The IRQ relates to which bit the interrupt
* comes in on. This makes interrupt processing much easier.
*/
static int
alcor_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
static char irq_tab[7][5] = {
/*INT INTA INTB INTC INTD */
/* note: IDSEL 17 is XLT only */
{16+13, 16+13, 16+13, 16+13, 16+13}, /* IdSel 17, TULIP */
{ 16+8, 16+8, 16+9, 16+10, 16+11}, /* IdSel 18, slot 0 */
{16+16, 16+16, 16+17, 16+18, 16+19}, /* IdSel 19, slot 3 */
{16+12, 16+12, 16+13, 16+14, 16+15}, /* IdSel 20, slot 4 */
{ -1, -1, -1, -1, -1}, /* IdSel 21, PCEB */
{ 16+0, 16+0, 16+1, 16+2, 16+3}, /* IdSel 22, slot 2 */
{ 16+4, 16+4, 16+5, 16+6, 16+7}, /* IdSel 23, slot 1 */
};
const long min_idsel = 6, max_idsel = 12, irqs_per_slot = 5;
return COMMON_TABLE_LOOKUP;
}
static void
alcor_kill_arch(int mode)
{
cia_kill_arch(mode);
#ifndef ALPHA_RESTORE_SRM_SETUP
switch(mode) {
case LINUX_REBOOT_CMD_RESTART:
/* Who said DEC engineer's have no sense of humor? ;-) */
if (alpha_using_srm) {
*(vuip) GRU_RESET = 0x0000dead;
mb();
}
break;
case LINUX_REBOOT_CMD_HALT:
break;
case LINUX_REBOOT_CMD_POWER_OFF:
break;
}
halt();
#endif
}
static void __init
alcor_init_pci(void)
{
struct pci_dev *dev;
cia_init_pci();
/*
* Now we can look to see if we are really running on an XLT-type
* motherboard, by looking for a 21040 TULIP in slot 6, which is
* built into XLT and BRET/MAVERICK, but not available on ALCOR.
*/
dev = pci_get_device(PCI_VENDOR_ID_DEC,
PCI_DEVICE_ID_DEC_TULIP,
NULL);
if (dev && dev->devfn == PCI_DEVFN(6,0)) {
alpha_mv.sys.cia.gru_int_req_bits = XLT_GRU_INT_REQ_BITS;
printk(KERN_INFO "%s: Detected AS500 or XLT motherboard.\n",
__func__);
}
pci_dev_put(dev);
}
/*
* The System Vectors
*/
struct alpha_machine_vector alcor_mv __initmv = {
.vector_name = "Alcor",
DO_EV5_MMU,
DO_DEFAULT_RTC,
DO_CIA_IO,
.machine_check = cia_machine_check,
.max_isa_dma_address = ALPHA_ALCOR_MAX_ISA_DMA_ADDRESS,
.min_io_address = EISA_DEFAULT_IO_BASE,
.min_mem_address = CIA_DEFAULT_MEM_BASE,
.nr_irqs = 48,
.device_interrupt = alcor_device_interrupt,
.init_arch = cia_init_arch,
.init_irq = alcor_init_irq,
.init_rtc = common_init_rtc,
.init_pci = alcor_init_pci,
.kill_arch = alcor_kill_arch,
.pci_map_irq = alcor_map_irq,
.pci_swizzle = common_swizzle,
.sys = { .cia = {
.gru_int_req_bits = ALCOR_GRU_INT_REQ_BITS
}}
};
ALIAS_MV(alcor)
struct alpha_machine_vector xlt_mv __initmv = {
.vector_name = "XLT",
DO_EV5_MMU,
DO_DEFAULT_RTC,
DO_CIA_IO,
.machine_check = cia_machine_check,
.max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
.min_io_address = EISA_DEFAULT_IO_BASE,
.min_mem_address = CIA_DEFAULT_MEM_BASE,
.nr_irqs = 48,
.device_interrupt = alcor_device_interrupt,
.init_arch = cia_init_arch,
.init_irq = alcor_init_irq,
.init_rtc = common_init_rtc,
.init_pci = alcor_init_pci,
.kill_arch = alcor_kill_arch,
.pci_map_irq = alcor_map_irq,
.pci_swizzle = common_swizzle,
.sys = { .cia = {
.gru_int_req_bits = XLT_GRU_INT_REQ_BITS
}}
};
/* No alpha_mv alias for XLT, since we compile it in unconditionally
with ALCOR; setup_arch knows how to cope. */