From 3a93261f70c7b92f84fb211b66f1d4e66c0b3dce Mon Sep 17 00:00:00 2001 From: Ashish Kalra Date: Thu, 19 May 2011 08:54:28 -0500 Subject: powerpc: introduce the ePAPR embedded hypervisor vmpic driver The Freescale ePAPR reference hypervisor provides interrupt controller services via a hypercall interface, instead of emulating the MPIC controller. This is called the VMPIC. The ePAPR "virtual interrupt controller" provides interrupt controller services for external interrupts. External interrupts received by a partition can come from two sources: - Hardware interrupts - hardware interrupts come from external interrupt lines or on-chip I/O devices. - Virtual interrupts - virtual interrupts are generated by the hypervisor as part of some hypervisor service or hypervisor-created virtual device. Both types of interrupts are processed using the same programming model and same set of hypercalls. Signed-off-by: Ashish Kalra Signed-off-by: Timur Tabi Signed-off-by: Kumar Gala --- arch/powerpc/sysdev/ehv_pic.c | 302 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 302 insertions(+) create mode 100644 arch/powerpc/sysdev/ehv_pic.c (limited to 'arch/powerpc/sysdev/ehv_pic.c') diff --git a/arch/powerpc/sysdev/ehv_pic.c b/arch/powerpc/sysdev/ehv_pic.c new file mode 100644 index 000000000000..af1a5df46b3e --- /dev/null +++ b/arch/powerpc/sysdev/ehv_pic.c @@ -0,0 +1,302 @@ +/* + * Driver for ePAPR Embedded Hypervisor PIC + * + * Copyright 2008-2011 Freescale Semiconductor, Inc. + * + * Author: Ashish Kalra + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include "../../../kernel/irq/settings.h" + +static struct ehv_pic *global_ehv_pic; +static DEFINE_SPINLOCK(ehv_pic_lock); + +static u32 hwirq_intspec[NR_EHV_PIC_INTS]; +static u32 __iomem *mpic_percpu_base_vaddr; + +#define IRQ_TYPE_MPIC_DIRECT 4 +#define MPIC_EOI 0x00B0 + +/* + * Linux descriptor level callbacks + */ + +void ehv_pic_unmask_irq(struct irq_data *d) +{ + unsigned int src = virq_to_hw(d->irq); + + ev_int_set_mask(src, 0); +} + +void ehv_pic_mask_irq(struct irq_data *d) +{ + unsigned int src = virq_to_hw(d->irq); + + ev_int_set_mask(src, 1); +} + +void ehv_pic_end_irq(struct irq_data *d) +{ + unsigned int src = virq_to_hw(d->irq); + + ev_int_eoi(src); +} + +void ehv_pic_direct_end_irq(struct irq_data *d) +{ + out_be32(mpic_percpu_base_vaddr + MPIC_EOI / 4, 0); +} + +int ehv_pic_set_affinity(struct irq_data *d, const struct cpumask *dest, + bool force) +{ + unsigned int src = virq_to_hw(d->irq); + unsigned int config, prio, cpu_dest; + int cpuid = irq_choose_cpu(dest); + unsigned long flags; + + spin_lock_irqsave(&ehv_pic_lock, flags); + ev_int_get_config(src, &config, &prio, &cpu_dest); + ev_int_set_config(src, config, prio, cpuid); + spin_unlock_irqrestore(&ehv_pic_lock, flags); + + return 0; +} + +static unsigned int ehv_pic_type_to_vecpri(unsigned int type) +{ + /* Now convert sense value */ + + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQ_TYPE_EDGE_RISING: + return EHV_PIC_INFO(VECPRI_SENSE_EDGE) | + EHV_PIC_INFO(VECPRI_POLARITY_POSITIVE); + + case IRQ_TYPE_EDGE_FALLING: + case IRQ_TYPE_EDGE_BOTH: + return EHV_PIC_INFO(VECPRI_SENSE_EDGE) | + EHV_PIC_INFO(VECPRI_POLARITY_NEGATIVE); + + case IRQ_TYPE_LEVEL_HIGH: + return EHV_PIC_INFO(VECPRI_SENSE_LEVEL) | + EHV_PIC_INFO(VECPRI_POLARITY_POSITIVE); + + case IRQ_TYPE_LEVEL_LOW: + default: + return EHV_PIC_INFO(VECPRI_SENSE_LEVEL) | + EHV_PIC_INFO(VECPRI_POLARITY_NEGATIVE); + } +} + +int ehv_pic_set_irq_type(struct irq_data *d, unsigned int flow_type) +{ + unsigned int src = virq_to_hw(d->irq); + struct irq_desc *desc = irq_to_desc(d->irq); + unsigned int vecpri, vold, vnew, prio, cpu_dest; + unsigned long flags; + + if (flow_type == IRQ_TYPE_NONE) + flow_type = IRQ_TYPE_LEVEL_LOW; + + irq_settings_clr_level(desc); + irq_settings_set_trigger_mask(desc, flow_type); + if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) + irq_settings_set_level(desc); + + vecpri = ehv_pic_type_to_vecpri(flow_type); + + spin_lock_irqsave(&ehv_pic_lock, flags); + ev_int_get_config(src, &vold, &prio, &cpu_dest); + vnew = vold & ~(EHV_PIC_INFO(VECPRI_POLARITY_MASK) | + EHV_PIC_INFO(VECPRI_SENSE_MASK)); + vnew |= vecpri; + + /* + * TODO : Add specific interface call for platform to set + * individual interrupt priorities. + * platform currently using static/default priority for all ints + */ + + prio = 8; + + ev_int_set_config(src, vecpri, prio, cpu_dest); + + spin_unlock_irqrestore(&ehv_pic_lock, flags); + return 0; +} + +static struct irq_chip ehv_pic_irq_chip = { + .irq_mask = ehv_pic_mask_irq, + .irq_unmask = ehv_pic_unmask_irq, + .irq_eoi = ehv_pic_end_irq, + .irq_set_type = ehv_pic_set_irq_type, +}; + +static struct irq_chip ehv_pic_direct_eoi_irq_chip = { + .irq_mask = ehv_pic_mask_irq, + .irq_unmask = ehv_pic_unmask_irq, + .irq_eoi = ehv_pic_direct_end_irq, + .irq_set_type = ehv_pic_set_irq_type, +}; + +/* Return an interrupt vector or NO_IRQ if no interrupt is pending. */ +unsigned int ehv_pic_get_irq(void) +{ + int irq; + + BUG_ON(global_ehv_pic == NULL); + + if (global_ehv_pic->coreint_flag) + irq = mfspr(SPRN_EPR); /* if core int mode */ + else + ev_int_iack(0, &irq); /* legacy mode */ + + if (irq == 0xFFFF) /* 0xFFFF --> no irq is pending */ + return NO_IRQ; + + /* + * this will also setup revmap[] in the slow path for the first + * time, next calls will always use fast path by indexing revmap + */ + return irq_linear_revmap(global_ehv_pic->irqhost, irq); +} + +static int ehv_pic_host_match(struct irq_host *h, struct device_node *node) +{ + /* Exact match, unless ehv_pic node is NULL */ + return h->of_node == NULL || h->of_node == node; +} + +static int ehv_pic_host_map(struct irq_host *h, unsigned int virq, + irq_hw_number_t hw) +{ + struct ehv_pic *ehv_pic = h->host_data; + struct irq_chip *chip; + + /* Default chip */ + chip = &ehv_pic->hc_irq; + + if (mpic_percpu_base_vaddr) + if (hwirq_intspec[hw] & IRQ_TYPE_MPIC_DIRECT) + chip = &ehv_pic_direct_eoi_irq_chip; + + irq_set_chip_data(virq, chip); + /* + * using handle_fasteoi_irq as our irq handler, this will + * only call the eoi callback and suitable for the MPIC + * controller which set ISR/IPR automatically and clear the + * highest priority active interrupt in ISR/IPR when we do + * a specific eoi + */ + irq_set_chip_and_handler(virq, chip, handle_fasteoi_irq); + + /* Set default irq type */ + irq_set_irq_type(virq, IRQ_TYPE_NONE); + + return 0; +} + +static int ehv_pic_host_xlate(struct irq_host *h, struct device_node *ct, + const u32 *intspec, unsigned int intsize, + irq_hw_number_t *out_hwirq, unsigned int *out_flags) + +{ + /* + * interrupt sense values coming from the guest device tree + * interrupt specifiers can have four possible sense and + * level encoding information and they need to + * be translated between firmware type & linux type. + */ + + static unsigned char map_of_senses_to_linux_irqtype[4] = { + IRQ_TYPE_EDGE_FALLING, + IRQ_TYPE_EDGE_RISING, + IRQ_TYPE_LEVEL_LOW, + IRQ_TYPE_LEVEL_HIGH, + }; + + *out_hwirq = intspec[0]; + if (intsize > 1) { + hwirq_intspec[intspec[0]] = intspec[1]; + *out_flags = map_of_senses_to_linux_irqtype[intspec[1] & + ~IRQ_TYPE_MPIC_DIRECT]; + } else { + *out_flags = IRQ_TYPE_NONE; + } + + return 0; +} + +static struct irq_host_ops ehv_pic_host_ops = { + .match = ehv_pic_host_match, + .map = ehv_pic_host_map, + .xlate = ehv_pic_host_xlate, +}; + +void __init ehv_pic_init(void) +{ + struct device_node *np, *np2; + struct ehv_pic *ehv_pic; + int coreint_flag = 1; + + np = of_find_compatible_node(NULL, NULL, "epapr,hv-pic"); + if (!np) { + pr_err("ehv_pic_init: could not find epapr,hv-pic node\n"); + return; + } + + if (!of_find_property(np, "has-external-proxy", NULL)) + coreint_flag = 0; + + ehv_pic = kzalloc(sizeof(struct ehv_pic), GFP_KERNEL); + if (!ehv_pic) { + of_node_put(np); + return; + } + + ehv_pic->irqhost = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, + NR_EHV_PIC_INTS, &ehv_pic_host_ops, 0); + + if (!ehv_pic->irqhost) { + of_node_put(np); + return; + } + + np2 = of_find_compatible_node(NULL, NULL, "fsl,hv-mpic-per-cpu"); + if (np2) { + mpic_percpu_base_vaddr = of_iomap(np2, 0); + if (!mpic_percpu_base_vaddr) + pr_err("ehv_pic_init: of_iomap failed\n"); + + of_node_put(np2); + } + + ehv_pic->irqhost->host_data = ehv_pic; + ehv_pic->hc_irq = ehv_pic_irq_chip; + ehv_pic->hc_irq.irq_set_affinity = ehv_pic_set_affinity; + ehv_pic->coreint_flag = coreint_flag; + + global_ehv_pic = ehv_pic; + irq_set_default_host(global_ehv_pic->irqhost); +} -- cgit