diff options
Diffstat (limited to 'arch/ppc/syslib/ppc4xx_pic.c')
-rw-r--r-- | arch/ppc/syslib/ppc4xx_pic.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/arch/ppc/syslib/ppc4xx_pic.c b/arch/ppc/syslib/ppc4xx_pic.c new file mode 100644 index 00000000000..08f06dd17e7 --- /dev/null +++ b/arch/ppc/syslib/ppc4xx_pic.c @@ -0,0 +1,244 @@ +/* + * arch/ppc/syslib/ppc4xx_pic.c + * + * Interrupt controller driver for PowerPC 4xx-based processors. + * + * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net> + * Copyright (c) 2004, 2005 Zultys Technologies + * + * Based on original code by + * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu> + * Armin Custer <akuster@mvista.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. +*/ +#include <linux/config.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/stddef.h> + +#include <asm/processor.h> +#include <asm/system.h> +#include <asm/irq.h> +#include <asm/ppc4xx_pic.h> + +/* See comment in include/arch-ppc/ppc4xx_pic.h + * for more info about these two variables + */ +extern struct ppc4xx_uic_settings ppc4xx_core_uic_cfg[NR_UICS] + __attribute__ ((weak)); +extern unsigned char ppc4xx_uic_ext_irq_cfg[] __attribute__ ((weak)); + +#define IRQ_MASK_UIC0(irq) (1 << (31 - (irq))) +#define IRQ_MASK_UICx(irq) (1 << (31 - ((irq) & 0x1f))) +#define IRQ_MASK_UIC1(irq) IRQ_MASK_UICx(irq) +#define IRQ_MASK_UIC2(irq) IRQ_MASK_UICx(irq) + +#define UIC_HANDLERS(n) \ +static void ppc4xx_uic##n##_enable(unsigned int irq) \ +{ \ + ppc_cached_irq_mask[n] |= IRQ_MASK_UIC##n(irq); \ + mtdcr(DCRN_UIC_ER(UIC##n), ppc_cached_irq_mask[n]); \ +} \ + \ +static void ppc4xx_uic##n##_disable(unsigned int irq) \ +{ \ + ppc_cached_irq_mask[n] &= ~IRQ_MASK_UIC##n(irq); \ + mtdcr(DCRN_UIC_ER(UIC##n), ppc_cached_irq_mask[n]); \ + ACK_UIC##n##_PARENT \ +} \ + \ +static void ppc4xx_uic##n##_ack(unsigned int irq) \ +{ \ + u32 mask = IRQ_MASK_UIC##n(irq); \ + ppc_cached_irq_mask[n] &= ~mask; \ + mtdcr(DCRN_UIC_ER(UIC##n), ppc_cached_irq_mask[n]); \ + mtdcr(DCRN_UIC_SR(UIC##n), mask); \ + ACK_UIC##n##_PARENT \ +} \ + \ +static void ppc4xx_uic##n##_end(unsigned int irq) \ +{ \ + unsigned int status = irq_desc[irq].status; \ + u32 mask = IRQ_MASK_UIC##n(irq); \ + if (status & IRQ_LEVEL) { \ + mtdcr(DCRN_UIC_SR(UIC##n), mask); \ + ACK_UIC##n##_PARENT \ + } \ + if (!(status & (IRQ_DISABLED | IRQ_INPROGRESS))) { \ + ppc_cached_irq_mask[n] |= mask; \ + mtdcr(DCRN_UIC_ER(UIC##n), ppc_cached_irq_mask[n]); \ + } \ +} + +#define DECLARE_UIC(n) \ +{ \ + .typename = "UIC"#n, \ + .enable = ppc4xx_uic##n##_enable, \ + .disable = ppc4xx_uic##n##_disable, \ + .ack = ppc4xx_uic##n##_ack, \ + .end = ppc4xx_uic##n##_end, \ +} \ + +#if NR_UICS == 3 +#define ACK_UIC0_PARENT mtdcr(DCRN_UIC_SR(UICB), UICB_UIC0NC); +#define ACK_UIC1_PARENT mtdcr(DCRN_UIC_SR(UICB), UICB_UIC1NC); +#define ACK_UIC2_PARENT mtdcr(DCRN_UIC_SR(UICB), UICB_UIC2NC); +UIC_HANDLERS(0); +UIC_HANDLERS(1); +UIC_HANDLERS(2); + +static int ppc4xx_pic_get_irq(struct pt_regs *regs) +{ + u32 uicb = mfdcr(DCRN_UIC_MSR(UICB)); + if (uicb & UICB_UIC0NC) + return 32 - ffs(mfdcr(DCRN_UIC_MSR(UIC0))); + else if (uicb & UICB_UIC1NC) + return 64 - ffs(mfdcr(DCRN_UIC_MSR(UIC1))); + else if (uicb & UICB_UIC2NC) + return 96 - ffs(mfdcr(DCRN_UIC_MSR(UIC2))); + else + return -1; +} + +static void __init ppc4xx_pic_impl_init(void) +{ + /* Configure Base UIC */ + mtdcr(DCRN_UIC_CR(UICB), 0); + mtdcr(DCRN_UIC_TR(UICB), 0); + mtdcr(DCRN_UIC_PR(UICB), 0xffffffff); + mtdcr(DCRN_UIC_SR(UICB), 0xffffffff); + mtdcr(DCRN_UIC_ER(UICB), UICB_UIC0NC | UICB_UIC1NC | UICB_UIC2NC); +} + +#elif NR_UICS == 2 +#define ACK_UIC0_PARENT +#define ACK_UIC1_PARENT mtdcr(DCRN_UIC_SR(UIC0), UIC0_UIC1NC); +UIC_HANDLERS(0); +UIC_HANDLERS(1); + +static int ppc4xx_pic_get_irq(struct pt_regs *regs) +{ + u32 uic0 = mfdcr(DCRN_UIC_MSR(UIC0)); + if (uic0 & UIC0_UIC1NC) + return 64 - ffs(mfdcr(DCRN_UIC_MSR(UIC1))); + else + return uic0 ? 32 - ffs(uic0) : -1; +} + +static void __init ppc4xx_pic_impl_init(void) +{ + /* Enable cascade interrupt in UIC0 */ + ppc_cached_irq_mask[0] |= UIC0_UIC1NC; + mtdcr(DCRN_UIC_SR(UIC0), UIC0_UIC1NC); + mtdcr(DCRN_UIC_ER(UIC0), ppc_cached_irq_mask[0]); +} + +#elif NR_UICS == 1 +#define ACK_UIC0_PARENT +UIC_HANDLERS(0); + +static int ppc4xx_pic_get_irq(struct pt_regs *regs) +{ + u32 uic0 = mfdcr(DCRN_UIC_MSR(UIC0)); + return uic0 ? 32 - ffs(uic0) : -1; +} + +static inline void ppc4xx_pic_impl_init(void) +{ +} +#endif + +static struct ppc4xx_uic_impl { + struct hw_interrupt_type decl; + int base; /* Base DCR number */ +} __uic[] = { + { .decl = DECLARE_UIC(0), .base = UIC0 }, +#if NR_UICS > 1 + { .decl = DECLARE_UIC(1), .base = UIC1 }, +#if NR_UICS > 2 + { .decl = DECLARE_UIC(2), .base = UIC2 }, +#endif +#endif +}; + +static inline int is_level_sensitive(int irq) +{ + u32 tr = mfdcr(DCRN_UIC_TR(__uic[irq >> 5].base)); + return (tr & IRQ_MASK_UICx(irq)) == 0; +} + +void __init ppc4xx_pic_init(void) +{ + int i; + unsigned char *eirqs = ppc4xx_uic_ext_irq_cfg; + + for (i = 0; i < NR_UICS; ++i) { + int base = __uic[i].base; + + /* Disable everything by default */ + ppc_cached_irq_mask[i] = 0; + mtdcr(DCRN_UIC_ER(base), 0); + + /* We don't use critical interrupts */ + mtdcr(DCRN_UIC_CR(base), 0); + + /* Configure polarity and triggering */ + if (ppc4xx_core_uic_cfg) { + struct ppc4xx_uic_settings *p = ppc4xx_core_uic_cfg + i; + u32 mask = p->ext_irq_mask; + u32 pr = mfdcr(DCRN_UIC_PR(base)) & mask; + u32 tr = mfdcr(DCRN_UIC_TR(base)) & mask; + + /* "Fixed" interrupts (on-chip devices) */ + pr |= p->polarity & ~mask; + tr |= p->triggering & ~mask; + + /* Merge external IRQs settings if board port + * provided them + */ + if (eirqs && mask) { + pr &= ~mask; + tr &= ~mask; + while (mask) { + /* Extract current external IRQ mask */ + u32 eirq_mask = 1 << __ilog2(mask); + + if (!(*eirqs & IRQ_SENSE_LEVEL)) + tr |= eirq_mask; + + if (*eirqs & IRQ_POLARITY_POSITIVE) + pr |= eirq_mask; + + mask &= ~eirq_mask; + ++eirqs; + } + } + mtdcr(DCRN_UIC_PR(base), pr); + mtdcr(DCRN_UIC_TR(base), tr); + } + + /* ACK any pending interrupts to prevent false + * triggering after first enable + */ + mtdcr(DCRN_UIC_SR(base), 0xffffffff); + } + + /* Perform optional implementation specific setup + * (e.g. enable cascade interrupts for multi-UIC configurations) + */ + ppc4xx_pic_impl_init(); + + /* Attach low-level handlers */ + for (i = 0; i < (NR_UICS << 5); ++i) { + irq_desc[i].handler = &__uic[i >> 5].decl; + if (is_level_sensitive(i)) + irq_desc[i].status |= IRQ_LEVEL; + } + + ppc_md.get_irq = ppc4xx_pic_get_irq; +} |