diff options
Diffstat (limited to 'arch/ppc/syslib/ppc8xx_pic.c')
-rw-r--r-- | arch/ppc/syslib/ppc8xx_pic.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/ppc/syslib/ppc8xx_pic.c b/arch/ppc/syslib/ppc8xx_pic.c new file mode 100644 index 00000000000..d3b01c6c97d --- /dev/null +++ b/arch/ppc/syslib/ppc8xx_pic.c @@ -0,0 +1,130 @@ +#include <linux/config.h> +#include <linux/module.h> +#include <linux/stddef.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/interrupt.h> +#include <asm/irq.h> +#include <asm/8xx_immap.h> +#include <asm/mpc8xx.h> +#include "ppc8xx_pic.h" + +extern int cpm_get_irq(struct pt_regs *regs); + +/* The 8xx internal interrupt controller. It is usually + * the only interrupt controller. Some boards, like the MBX and + * Sandpoint have the 8259 as a secondary controller. Depending + * upon the processor type, the internal controller can have as + * few as 16 interrups or as many as 64. We could use the + * "clear_bit()" and "set_bit()" functions like other platforms, + * but they are overkill for us. + */ + +static void m8xx_mask_irq(unsigned int irq_nr) +{ + int bit, word; + + bit = irq_nr & 0x1f; + word = irq_nr >> 5; + + ppc_cached_irq_mask[word] &= ~(1 << (31-bit)); + ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask = + ppc_cached_irq_mask[word]; +} + +static void m8xx_unmask_irq(unsigned int irq_nr) +{ + int bit, word; + + bit = irq_nr & 0x1f; + word = irq_nr >> 5; + + ppc_cached_irq_mask[word] |= (1 << (31-bit)); + ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask = + ppc_cached_irq_mask[word]; +} + +static void m8xx_end_irq(unsigned int irq_nr) +{ + if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS)) + && irq_desc[irq_nr].action) { + int bit, word; + + bit = irq_nr & 0x1f; + word = irq_nr >> 5; + + ppc_cached_irq_mask[word] |= (1 << (31-bit)); + ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask = + ppc_cached_irq_mask[word]; + } +} + + +static void m8xx_mask_and_ack(unsigned int irq_nr) +{ + int bit, word; + + bit = irq_nr & 0x1f; + word = irq_nr >> 5; + + ppc_cached_irq_mask[word] &= ~(1 << (31-bit)); + ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask = + ppc_cached_irq_mask[word]; + ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sipend = 1 << (31-bit); +} + +struct hw_interrupt_type ppc8xx_pic = { + .typename = " 8xx SIU ", + .enable = m8xx_unmask_irq, + .disable = m8xx_mask_irq, + .ack = m8xx_mask_and_ack, + .end = m8xx_end_irq, +}; + +/* + * We either return a valid interrupt or -1 if there is nothing pending + */ +int +m8xx_get_irq(struct pt_regs *regs) +{ + int irq; + + /* For MPC8xx, read the SIVEC register and shift the bits down + * to get the irq number. + */ + irq = ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sivec >> 26; + + /* + * When we read the sivec without an interrupt to process, we will + * get back SIU_LEVEL7. In this case, return -1 + */ + if (irq == CPM_INTERRUPT) + irq = CPM_IRQ_OFFSET + cpm_get_irq(regs); +#if defined(CONFIG_PCI) + else if (irq == ISA_BRIDGE_INT) { + int isa_irq; + + if ((isa_irq = i8259_poll(regs)) >= 0) + irq = I8259_IRQ_OFFSET + isa_irq; + } +#endif /* CONFIG_PCI */ + else if (irq == SIU_LEVEL7) + irq = -1; + + return irq; +} + +#if defined(CONFIG_MBX) && defined(CONFIG_PCI) +/* Only the MBX uses the external 8259. This allows us to catch standard + * drivers that may mess up the internal interrupt controllers, and also + * allow them to run without modification on the MBX. + */ +void mbx_i8259_action(int irq, void *dev_id, struct pt_regs *regs) +{ + /* This interrupt handler never actually gets called. It is + * installed only to unmask the 8259 cascade interrupt in the SIU + * and to make the 8259 cascade interrupt visible in /proc/interrupts. + */ +} +#endif /* CONFIG_PCI */ |