diff options
Diffstat (limited to 'arch/sh/boards/cayman/irq.c')
| -rw-r--r-- | arch/sh/boards/cayman/irq.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/arch/sh/boards/cayman/irq.c b/arch/sh/boards/cayman/irq.c new file mode 100644 index 000000000000..30ec7bebfaf1 --- /dev/null +++ b/arch/sh/boards/cayman/irq.c @@ -0,0 +1,197 @@ +/* + * arch/sh/mach-cayman/irq.c - SH-5 Cayman Interrupt Support + * + * This file handles the board specific parts of the Cayman interrupt system + * + * Copyright (C) 2002 Stuart Menefy + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/signal.h> +#include <asm/cpu/irq.h> +#include <asm/page.h> + +/* Setup for the SMSC FDC37C935 / LAN91C100FD */ +#define SMSC_IRQ IRQ_IRL1 + +/* Setup for PCI Bus 2, which transmits interrupts via the EPLD */ +#define PCI2_IRQ IRQ_IRL3 + +unsigned long epld_virt; + +#define EPLD_BASE 0x04002000 +#define EPLD_STATUS_BASE (epld_virt + 0x10) +#define EPLD_MASK_BASE (epld_virt + 0x20) + +/* Note the SMSC SuperIO chip and SMSC LAN chip interrupts are all muxed onto + the same SH-5 interrupt */ + +static irqreturn_t cayman_interrupt_smsc(int irq, void *dev_id) +{ + printk(KERN_INFO "CAYMAN: spurious SMSC interrupt\n"); + return IRQ_NONE; +} + +static irqreturn_t cayman_interrupt_pci2(int irq, void *dev_id) +{ + printk(KERN_INFO "CAYMAN: spurious PCI interrupt, IRQ %d\n", irq); + return IRQ_NONE; +} + +static struct irqaction cayman_action_smsc = { + .name = "Cayman SMSC Mux", + .handler = cayman_interrupt_smsc, + .flags = IRQF_DISABLED, +}; + +static struct irqaction cayman_action_pci2 = { + .name = "Cayman PCI2 Mux", + .handler = cayman_interrupt_pci2, + .flags = IRQF_DISABLED, +}; + +static void enable_cayman_irq(unsigned int irq) +{ + unsigned long flags; + unsigned long mask; + unsigned int reg; + unsigned char bit; + + irq -= START_EXT_IRQS; + reg = EPLD_MASK_BASE + ((irq / 8) << 2); + bit = 1<<(irq % 8); + local_irq_save(flags); + mask = ctrl_inl(reg); + mask |= bit; + ctrl_outl(mask, reg); + local_irq_restore(flags); +} + +void disable_cayman_irq(unsigned int irq) +{ + unsigned long flags; + unsigned long mask; + unsigned int reg; + unsigned char bit; + + irq -= START_EXT_IRQS; + reg = EPLD_MASK_BASE + ((irq / 8) << 2); + bit = 1<<(irq % 8); + local_irq_save(flags); + mask = ctrl_inl(reg); + mask &= ~bit; + ctrl_outl(mask, reg); + local_irq_restore(flags); +} + +static void ack_cayman_irq(unsigned int irq) +{ + disable_cayman_irq(irq); +} + +static void end_cayman_irq(unsigned int irq) +{ + if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))) + enable_cayman_irq(irq); +} + +static unsigned int startup_cayman_irq(unsigned int irq) +{ + enable_cayman_irq(irq); + return 0; /* never anything pending */ +} + +static void shutdown_cayman_irq(unsigned int irq) +{ + disable_cayman_irq(irq); +} + +struct hw_interrupt_type cayman_irq_type = { + .typename = "Cayman-IRQ", + .startup = startup_cayman_irq, + .shutdown = shutdown_cayman_irq, + .enable = enable_cayman_irq, + .disable = disable_cayman_irq, + .ack = ack_cayman_irq, + .end = end_cayman_irq, +}; + +int cayman_irq_demux(int evt) +{ + int irq = intc_evt_to_irq[evt]; + + if (irq == SMSC_IRQ) { + unsigned long status; + int i; + + status = ctrl_inl(EPLD_STATUS_BASE) & + ctrl_inl(EPLD_MASK_BASE) & 0xff; + if (status == 0) { + irq = -1; + } else { + for (i=0; i<8; i++) { + if (status & (1<<i)) + break; + } + irq = START_EXT_IRQS + i; + } + } + + if (irq == PCI2_IRQ) { + unsigned long status; + int i; + + status = ctrl_inl(EPLD_STATUS_BASE + 3 * sizeof(u32)) & + ctrl_inl(EPLD_MASK_BASE + 3 * sizeof(u32)) & 0xff; + if (status == 0) { + irq = -1; + } else { + for (i=0; i<8; i++) { + if (status & (1<<i)) + break; + } + irq = START_EXT_IRQS + (3 * 8) + i; + } + } + + return irq; +} + +#if defined(CONFIG_PROC_FS) && defined(CONFIG_SYSCTL) +int cayman_irq_describe(char* p, int irq) +{ + if (irq < NR_INTC_IRQS) { + return intc_irq_describe(p, irq); + } else if (irq < NR_INTC_IRQS + 8) { + return sprintf(p, "(SMSC %d)", irq - NR_INTC_IRQS); + } else if ((irq >= NR_INTC_IRQS + 24) && (irq < NR_INTC_IRQS + 32)) { + return sprintf(p, "(PCI2 %d)", irq - (NR_INTC_IRQS + 24)); + } + + return 0; +} +#endif + +void init_cayman_irq(void) +{ + int i; + + epld_virt = onchip_remap(EPLD_BASE, 1024, "EPLD"); + if (!epld_virt) { + printk(KERN_ERR "Cayman IRQ: Unable to remap EPLD\n"); + return; + } + + for (i=0; i<NR_EXT_IRQS; i++) { + irq_desc[START_EXT_IRQS + i].chip = &cayman_irq_type; + } + + /* Setup the SMSC interrupt */ + setup_irq(SMSC_IRQ, &cayman_action_smsc); + setup_irq(PCI2_IRQ, &cayman_action_pci2); +} |
