diff options
Diffstat (limited to 'arch/ppc/syslib/cpm2_pic.c')
| -rw-r--r-- | arch/ppc/syslib/cpm2_pic.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/arch/ppc/syslib/cpm2_pic.c b/arch/ppc/syslib/cpm2_pic.c new file mode 100644 index 000000000000..954b07fc1df3 --- /dev/null +++ b/arch/ppc/syslib/cpm2_pic.c @@ -0,0 +1,172 @@ +/* The CPM2 internal interrupt controller. It is usually + * the only interrupt controller. + * There are two 32-bit registers (high/low) for up to 64 + * possible interrupts. + * + * Now, the fun starts.....Interrupt Numbers DO NOT MAP + * in a simple arithmetic fashion to mask or pending registers. + * That is, interrupt 4 does not map to bit position 4. + * We create two tables, indexed by vector number, to indicate + * which register to use and which bit in the register to use. + */ + +#include <linux/stddef.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/irq.h> + +#include <asm/immap_cpm2.h> +#include <asm/mpc8260.h> + +#include "cpm2_pic.h" + +static u_char irq_to_siureg[] = { + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0 +}; + +/* bit numbers do not match the docs, these are precomputed so the bit for + * a given irq is (1 << irq_to_siubit[irq]) */ +static u_char irq_to_siubit[] = { + 0, 15, 14, 13, 12, 11, 10, 9, + 8, 7, 6, 5, 4, 3, 2, 1, + 2, 1, 15, 14, 13, 12, 11, 10, + 9, 8, 7, 6, 5, 4, 3, 0, + 31, 30, 29, 28, 27, 26, 25, 24, + 23, 22, 21, 20, 19, 18, 17, 16, + 16, 17, 18, 19, 20, 21, 22, 23, + 24, 25, 26, 27, 28, 29, 30, 31, +}; + +static void cpm2_mask_irq(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr; + + irq_nr -= CPM_IRQ_OFFSET; + + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_immr->im_intctl.ic_simrh); + ppc_cached_irq_mask[word] &= ~(1 << bit); + simr[word] = ppc_cached_irq_mask[word]; +} + +static void cpm2_unmask_irq(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr; + + irq_nr -= CPM_IRQ_OFFSET; + + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_immr->im_intctl.ic_simrh); + ppc_cached_irq_mask[word] |= 1 << bit; + simr[word] = ppc_cached_irq_mask[word]; +} + +static void cpm2_mask_and_ack(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr, *sipnr; + + irq_nr -= CPM_IRQ_OFFSET; + + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_immr->im_intctl.ic_simrh); + sipnr = &(cpm2_immr->im_intctl.ic_sipnrh); + ppc_cached_irq_mask[word] &= ~(1 << bit); + simr[word] = ppc_cached_irq_mask[word]; + sipnr[word] = 1 << bit; +} + +static void cpm2_end_irq(unsigned int irq_nr) +{ + int bit, word; + volatile uint *simr; + + if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS)) + && irq_desc[irq_nr].action) { + + irq_nr -= CPM_IRQ_OFFSET; + bit = irq_to_siubit[irq_nr]; + word = irq_to_siureg[irq_nr]; + + simr = &(cpm2_immr->im_intctl.ic_simrh); + ppc_cached_irq_mask[word] |= 1 << bit; + simr[word] = ppc_cached_irq_mask[word]; + } +} + +static struct hw_interrupt_type cpm2_pic = { + .typename = " CPM2 SIU ", + .enable = cpm2_unmask_irq, + .disable = cpm2_mask_irq, + .ack = cpm2_mask_and_ack, + .end = cpm2_end_irq, +}; + +int cpm2_get_irq(struct pt_regs *regs) +{ + int irq; + unsigned long bits; + + /* For CPM2, read the SIVEC register and shift the bits down + * to get the irq number. */ + bits = cpm2_immr->im_intctl.ic_sivec; + irq = bits >> 26; + + if (irq == 0) + return(-1); + return irq+CPM_IRQ_OFFSET; +} + +void cpm2_init_IRQ(void) +{ + int i; + + /* Clear the CPM IRQ controller, in case it has any bits set + * from the bootloader + */ + + /* Mask out everything */ + cpm2_immr->im_intctl.ic_simrh = 0x00000000; + cpm2_immr->im_intctl.ic_simrl = 0x00000000; + wmb(); + + /* Ack everything */ + cpm2_immr->im_intctl.ic_sipnrh = 0xffffffff; + cpm2_immr->im_intctl.ic_sipnrl = 0xffffffff; + wmb(); + + /* Dummy read of the vector */ + i = cpm2_immr->im_intctl.ic_sivec; + rmb(); + + /* Initialize the default interrupt mapping priorities, + * in case the boot rom changed something on us. + */ + cpm2_immr->im_intctl.ic_sicr = 0; + cpm2_immr->im_intctl.ic_scprrh = 0x05309770; + cpm2_immr->im_intctl.ic_scprrl = 0x05309770; + + + /* Enable chaining to OpenPIC, and make everything level + */ + for (i = 0; i < NR_CPM_INTS; i++) { + irq_desc[i+CPM_IRQ_OFFSET].handler = &cpm2_pic; + irq_desc[i+CPM_IRQ_OFFSET].status |= IRQ_LEVEL; + } +} |