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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/alpha/kernel/irq_pyxis.c | |
download | talos-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz talos-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/alpha/kernel/irq_pyxis.c')
-rw-r--r-- | arch/alpha/kernel/irq_pyxis.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/alpha/kernel/irq_pyxis.c b/arch/alpha/kernel/irq_pyxis.c new file mode 100644 index 000000000000..146a20b9e3d5 --- /dev/null +++ b/arch/alpha/kernel/irq_pyxis.c @@ -0,0 +1,127 @@ +/* + * linux/arch/alpha/kernel/irq_pyxis.c + * + * Based on code written by David A Rusling (david.rusling@reo.mts.dec.com). + * + * IRQ Code common to all PYXIS core logic chips. + */ + +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/irq.h> + +#include <asm/io.h> +#include <asm/core_cia.h> + +#include "proto.h" +#include "irq_impl.h" + + +/* Note mask bit is true for ENABLED irqs. */ +static unsigned long cached_irq_mask; + +static inline void +pyxis_update_irq_hw(unsigned long mask) +{ + *(vulp)PYXIS_INT_MASK = mask; + mb(); + *(vulp)PYXIS_INT_MASK; +} + +static inline void +pyxis_enable_irq(unsigned int irq) +{ + pyxis_update_irq_hw(cached_irq_mask |= 1UL << (irq - 16)); +} + +static void +pyxis_disable_irq(unsigned int irq) +{ + pyxis_update_irq_hw(cached_irq_mask &= ~(1UL << (irq - 16))); +} + +static unsigned int +pyxis_startup_irq(unsigned int irq) +{ + pyxis_enable_irq(irq); + return 0; +} + +static void +pyxis_end_irq(unsigned int irq) +{ + if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))) + pyxis_enable_irq(irq); +} + +static void +pyxis_mask_and_ack_irq(unsigned int irq) +{ + unsigned long bit = 1UL << (irq - 16); + unsigned long mask = cached_irq_mask &= ~bit; + + /* Disable the interrupt. */ + *(vulp)PYXIS_INT_MASK = mask; + wmb(); + /* Ack PYXIS PCI interrupt. */ + *(vulp)PYXIS_INT_REQ = bit; + mb(); + /* Re-read to force both writes. */ + *(vulp)PYXIS_INT_MASK; +} + +static struct hw_interrupt_type pyxis_irq_type = { + .typename = "PYXIS", + .startup = pyxis_startup_irq, + .shutdown = pyxis_disable_irq, + .enable = pyxis_enable_irq, + .disable = pyxis_disable_irq, + .ack = pyxis_mask_and_ack_irq, + .end = pyxis_end_irq, +}; + +void +pyxis_device_interrupt(unsigned long vector, struct pt_regs *regs) +{ + unsigned long pld; + unsigned int i; + + /* Read the interrupt summary register of PYXIS */ + pld = *(vulp)PYXIS_INT_REQ; + pld &= cached_irq_mask; + + /* + * 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 == 7) + isa_device_interrupt(vector, regs); + else + handle_irq(16+i, regs); + } +} + +void __init +init_pyxis_irqs(unsigned long ignore_mask) +{ + long i; + + *(vulp)PYXIS_INT_MASK = 0; /* disable all */ + *(vulp)PYXIS_INT_REQ = -1; /* flush all */ + mb(); + + /* Send -INTA pulses to clear any pending interrupts ...*/ + *(vuip) CIA_IACK_SC; + + for (i = 16; i < 48; ++i) { + if ((ignore_mask >> i) & 1) + continue; + irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL; + irq_desc[i].handler = &pyxis_irq_type; + } + + setup_irq(16+7, &isa_cascade_irqaction); +} |