diff options
Diffstat (limited to 'arch/mips/sgi-ip22/ip22-int.c')
| -rw-r--r-- | arch/mips/sgi-ip22/ip22-int.c | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/arch/mips/sgi-ip22/ip22-int.c b/arch/mips/sgi-ip22/ip22-int.c new file mode 100644 index 000000000..3804895fa --- /dev/null +++ b/arch/mips/sgi-ip22/ip22-int.c @@ -0,0 +1,339 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ip22-int.c: Routines for generic manipulation of the INT[23] ASIC + * found on INDY and Indigo2 workstations. + * + * Copyright (C) 1996 David S. Miller (davem@davemloft.net) + * Copyright (C) 1997, 1998 Ralf Baechle (ralf@gnu.org) + * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu) + * - Indigo2 changes + * - Interrupt handling fixes + * Copyright (C) 2001, 2003 Ladislav Michl (ladis@linux-mips.org) + */ +#include <linux/types.h> +#include <linux/init.h> +#include <linux/kernel_stat.h> +#include <linux/interrupt.h> +#include <linux/ftrace.h> + +#include <asm/irq_cpu.h> +#include <asm/sgi/hpc3.h> +#include <asm/sgi/ip22.h> + +/* So far nothing hangs here */ +#undef USE_LIO3_IRQ + +struct sgint_regs *sgint; + +static char lc0msk_to_irqnr[256]; +static char lc1msk_to_irqnr[256]; +static char lc2msk_to_irqnr[256]; +static char lc3msk_to_irqnr[256]; + +extern int ip22_eisa_init(void); + +static void enable_local0_irq(struct irq_data *d) +{ + /* don't allow mappable interrupt to be enabled from setup_irq, + * we have our own way to do so */ + if (d->irq != SGI_MAP_0_IRQ) + sgint->imask0 |= (1 << (d->irq - SGINT_LOCAL0)); +} + +static void disable_local0_irq(struct irq_data *d) +{ + sgint->imask0 &= ~(1 << (d->irq - SGINT_LOCAL0)); +} + +static struct irq_chip ip22_local0_irq_type = { + .name = "IP22 local 0", + .irq_mask = disable_local0_irq, + .irq_unmask = enable_local0_irq, +}; + +static void enable_local1_irq(struct irq_data *d) +{ + /* don't allow mappable interrupt to be enabled from setup_irq, + * we have our own way to do so */ + if (d->irq != SGI_MAP_1_IRQ) + sgint->imask1 |= (1 << (d->irq - SGINT_LOCAL1)); +} + +static void disable_local1_irq(struct irq_data *d) +{ + sgint->imask1 &= ~(1 << (d->irq - SGINT_LOCAL1)); +} + +static struct irq_chip ip22_local1_irq_type = { + .name = "IP22 local 1", + .irq_mask = disable_local1_irq, + .irq_unmask = enable_local1_irq, +}; + +static void enable_local2_irq(struct irq_data *d) +{ + sgint->imask0 |= (1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0)); + sgint->cmeimask0 |= (1 << (d->irq - SGINT_LOCAL2)); +} + +static void disable_local2_irq(struct irq_data *d) +{ + sgint->cmeimask0 &= ~(1 << (d->irq - SGINT_LOCAL2)); + if (!sgint->cmeimask0) + sgint->imask0 &= ~(1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0)); +} + +static struct irq_chip ip22_local2_irq_type = { + .name = "IP22 local 2", + .irq_mask = disable_local2_irq, + .irq_unmask = enable_local2_irq, +}; + +static void enable_local3_irq(struct irq_data *d) +{ + sgint->imask1 |= (1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1)); + sgint->cmeimask1 |= (1 << (d->irq - SGINT_LOCAL3)); +} + +static void disable_local3_irq(struct irq_data *d) +{ + sgint->cmeimask1 &= ~(1 << (d->irq - SGINT_LOCAL3)); + if (!sgint->cmeimask1) + sgint->imask1 &= ~(1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1)); +} + +static struct irq_chip ip22_local3_irq_type = { + .name = "IP22 local 3", + .irq_mask = disable_local3_irq, + .irq_unmask = enable_local3_irq, +}; + +static void indy_local0_irqdispatch(void) +{ + u8 mask = sgint->istat0 & sgint->imask0; + u8 mask2; + int irq; + + if (mask & SGINT_ISTAT0_LIO2) { + mask2 = sgint->vmeistat & sgint->cmeimask0; + irq = lc2msk_to_irqnr[mask2]; + } else + irq = lc0msk_to_irqnr[mask]; + + /* + * workaround for INT2 bug; if irq == 0, INT2 has seen a fifo full + * irq, but failed to latch it into status register + */ + if (irq) + do_IRQ(irq); + else + do_IRQ(SGINT_LOCAL0 + 0); +} + +static void indy_local1_irqdispatch(void) +{ + u8 mask = sgint->istat1 & sgint->imask1; + u8 mask2; + int irq; + + if (mask & SGINT_ISTAT1_LIO3) { + mask2 = sgint->vmeistat & sgint->cmeimask1; + irq = lc3msk_to_irqnr[mask2]; + } else + irq = lc1msk_to_irqnr[mask]; + + /* if irq == 0, then the interrupt has already been cleared */ + if (irq) + do_IRQ(irq); +} + +extern void ip22_be_interrupt(int irq); + +static void __irq_entry indy_buserror_irq(void) +{ + int irq = SGI_BUSERR_IRQ; + + irq_enter(); + kstat_incr_irq_this_cpu(irq); + ip22_be_interrupt(irq); + irq_exit(); +} + +static struct irqaction local0_cascade = { + .handler = no_action, + .flags = IRQF_NO_THREAD, + .name = "local0 cascade", +}; + +static struct irqaction local1_cascade = { + .handler = no_action, + .flags = IRQF_NO_THREAD, + .name = "local1 cascade", +}; + +static struct irqaction buserr = { + .handler = no_action, + .flags = IRQF_NO_THREAD, + .name = "Bus Error", +}; + +static struct irqaction map0_cascade = { + .handler = no_action, + .flags = IRQF_NO_THREAD, + .name = "mapable0 cascade", +}; + +#ifdef USE_LIO3_IRQ +static struct irqaction map1_cascade = { + .handler = no_action, + .flags = IRQF_NO_THREAD, + .name = "mapable1 cascade", +}; +#define SGI_INTERRUPTS SGINT_END +#else +#define SGI_INTERRUPTS SGINT_LOCAL3 +#endif + +extern void indy_8254timer_irq(void); + +/* + * IRQs on the INDY look basically (barring software IRQs which we don't use + * at all) like: + * + * MIPS IRQ Source + * -------- ------ + * 0 Software (ignored) + * 1 Software (ignored) + * 2 Local IRQ level zero + * 3 Local IRQ level one + * 4 8254 Timer zero + * 5 8254 Timer one + * 6 Bus Error + * 7 R4k timer (what we use) + * + * We handle the IRQ according to _our_ priority which is: + * + * Highest ---- R4k Timer + * Local IRQ zero + * Local IRQ one + * Bus Error + * 8254 Timer zero + * Lowest ---- 8254 Timer one + * + * then we just return, if multiple IRQs are pending then we will just take + * another exception, big deal. + */ + +asmlinkage void plat_irq_dispatch(void) +{ + unsigned int pending = read_c0_status() & read_c0_cause(); + + /* + * First we check for r4k counter/timer IRQ. + */ + if (pending & CAUSEF_IP7) + do_IRQ(SGI_TIMER_IRQ); + else if (pending & CAUSEF_IP2) + indy_local0_irqdispatch(); + else if (pending & CAUSEF_IP3) + indy_local1_irqdispatch(); + else if (pending & CAUSEF_IP6) + indy_buserror_irq(); + else if (pending & (CAUSEF_IP4 | CAUSEF_IP5)) + indy_8254timer_irq(); +} + +void __init arch_init_irq(void) +{ + int i; + + /* Init local mask --> irq tables. */ + for (i = 0; i < 256; i++) { + if (i & 0x80) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 7; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 7; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 7; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 7; + } else if (i & 0x40) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 6; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 6; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 6; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 6; + } else if (i & 0x20) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 5; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 5; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 5; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 5; + } else if (i & 0x10) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 4; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 4; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 4; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 4; + } else if (i & 0x08) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 3; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 3; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 3; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 3; + } else if (i & 0x04) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 2; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 2; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 2; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 2; + } else if (i & 0x02) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 1; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 1; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 1; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 1; + } else if (i & 0x01) { + lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 0; + lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 0; + lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 0; + lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 0; + } else { + lc0msk_to_irqnr[i] = 0; + lc1msk_to_irqnr[i] = 0; + lc2msk_to_irqnr[i] = 0; + lc3msk_to_irqnr[i] = 0; + } + } + + /* Mask out all interrupts. */ + sgint->imask0 = 0; + sgint->imask1 = 0; + sgint->cmeimask0 = 0; + sgint->cmeimask1 = 0; + + /* init CPU irqs */ + mips_cpu_irq_init(); + + for (i = SGINT_LOCAL0; i < SGI_INTERRUPTS; i++) { + struct irq_chip *handler; + + if (i < SGINT_LOCAL1) + handler = &ip22_local0_irq_type; + else if (i < SGINT_LOCAL2) + handler = &ip22_local1_irq_type; + else if (i < SGINT_LOCAL3) + handler = &ip22_local2_irq_type; + else + handler = &ip22_local3_irq_type; + + irq_set_chip_and_handler(i, handler, handle_level_irq); + } + + /* vector handler. this register the IRQ as non-sharable */ + setup_irq(SGI_LOCAL_0_IRQ, &local0_cascade); + setup_irq(SGI_LOCAL_1_IRQ, &local1_cascade); + setup_irq(SGI_BUSERR_IRQ, &buserr); + + /* cascade in cascade. i love Indy ;-) */ + setup_irq(SGI_MAP_0_IRQ, &map0_cascade); +#ifdef USE_LIO3_IRQ + setup_irq(SGI_MAP_1_IRQ, &map1_cascade); +#endif + +#ifdef CONFIG_EISA + if (ip22_is_fullhouse()) /* Only Indigo-2 has EISA stuff */ + ip22_eisa_init(); +#endif +} |