cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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irq-xtensa-mx.c (4832B)


      1/*
      2 * Xtensa MX interrupt distributor
      3 *
      4 * Copyright (C) 2002 - 2013 Tensilica, Inc.
      5 *
      6 * This file is subject to the terms and conditions of the GNU General Public
      7 * License.  See the file "COPYING" in the main directory of this archive
      8 * for more details.
      9 */
     10
     11#include <linux/interrupt.h>
     12#include <linux/irqdomain.h>
     13#include <linux/irq.h>
     14#include <linux/irqchip.h>
     15#include <linux/of.h>
     16
     17#include <asm/mxregs.h>
     18
     19#define HW_IRQ_IPI_COUNT 2
     20#define HW_IRQ_MX_BASE 2
     21#define HW_IRQ_EXTERN_BASE 3
     22
     23static DEFINE_PER_CPU(unsigned int, cached_irq_mask);
     24
     25static int xtensa_mx_irq_map(struct irq_domain *d, unsigned int irq,
     26		irq_hw_number_t hw)
     27{
     28	if (hw < HW_IRQ_IPI_COUNT) {
     29		struct irq_chip *irq_chip = d->host_data;
     30		irq_set_chip_and_handler_name(irq, irq_chip,
     31				handle_percpu_irq, "ipi");
     32		irq_set_status_flags(irq, IRQ_LEVEL);
     33		return 0;
     34	}
     35	irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
     36	return xtensa_irq_map(d, irq, hw);
     37}
     38
     39/*
     40 * Device Tree IRQ specifier translation function which works with one or
     41 * two cell bindings. First cell value maps directly to the hwirq number.
     42 * Second cell if present specifies whether hwirq number is external (1) or
     43 * internal (0).
     44 */
     45static int xtensa_mx_irq_domain_xlate(struct irq_domain *d,
     46		struct device_node *ctrlr,
     47		const u32 *intspec, unsigned int intsize,
     48		unsigned long *out_hwirq, unsigned int *out_type)
     49{
     50	return xtensa_irq_domain_xlate(intspec, intsize,
     51			intspec[0], intspec[0] + HW_IRQ_EXTERN_BASE,
     52			out_hwirq, out_type);
     53}
     54
     55static const struct irq_domain_ops xtensa_mx_irq_domain_ops = {
     56	.xlate = xtensa_mx_irq_domain_xlate,
     57	.map = xtensa_mx_irq_map,
     58};
     59
     60void secondary_init_irq(void)
     61{
     62	__this_cpu_write(cached_irq_mask,
     63			XCHAL_INTTYPE_MASK_EXTERN_EDGE |
     64			XCHAL_INTTYPE_MASK_EXTERN_LEVEL);
     65	xtensa_set_sr(XCHAL_INTTYPE_MASK_EXTERN_EDGE |
     66			XCHAL_INTTYPE_MASK_EXTERN_LEVEL, intenable);
     67}
     68
     69static void xtensa_mx_irq_mask(struct irq_data *d)
     70{
     71	unsigned int mask = 1u << d->hwirq;
     72
     73	if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
     74		    XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) {
     75		unsigned int ext_irq = xtensa_get_ext_irq_no(d->hwirq);
     76
     77		if (ext_irq >= HW_IRQ_MX_BASE) {
     78			set_er(1u << (ext_irq - HW_IRQ_MX_BASE), MIENG);
     79			return;
     80		}
     81	}
     82	mask = __this_cpu_read(cached_irq_mask) & ~mask;
     83	__this_cpu_write(cached_irq_mask, mask);
     84	xtensa_set_sr(mask, intenable);
     85}
     86
     87static void xtensa_mx_irq_unmask(struct irq_data *d)
     88{
     89	unsigned int mask = 1u << d->hwirq;
     90
     91	if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
     92		    XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) {
     93		unsigned int ext_irq = xtensa_get_ext_irq_no(d->hwirq);
     94
     95		if (ext_irq >= HW_IRQ_MX_BASE) {
     96			set_er(1u << (ext_irq - HW_IRQ_MX_BASE), MIENGSET);
     97			return;
     98		}
     99	}
    100	mask |= __this_cpu_read(cached_irq_mask);
    101	__this_cpu_write(cached_irq_mask, mask);
    102	xtensa_set_sr(mask, intenable);
    103}
    104
    105static void xtensa_mx_irq_enable(struct irq_data *d)
    106{
    107	xtensa_mx_irq_unmask(d);
    108}
    109
    110static void xtensa_mx_irq_disable(struct irq_data *d)
    111{
    112	xtensa_mx_irq_mask(d);
    113}
    114
    115static void xtensa_mx_irq_ack(struct irq_data *d)
    116{
    117	xtensa_set_sr(1 << d->hwirq, intclear);
    118}
    119
    120static int xtensa_mx_irq_retrigger(struct irq_data *d)
    121{
    122	unsigned int mask = 1u << d->hwirq;
    123
    124	if (WARN_ON(mask & ~XCHAL_INTTYPE_MASK_SOFTWARE))
    125		return 0;
    126	xtensa_set_sr(mask, intset);
    127	return 1;
    128}
    129
    130static int xtensa_mx_irq_set_affinity(struct irq_data *d,
    131		const struct cpumask *dest, bool force)
    132{
    133	int cpu = cpumask_any_and(dest, cpu_online_mask);
    134	unsigned mask = 1u << cpu;
    135
    136	set_er(mask, MIROUT(d->hwirq - HW_IRQ_MX_BASE));
    137	irq_data_update_effective_affinity(d, cpumask_of(cpu));
    138
    139	return 0;
    140
    141}
    142
    143static struct irq_chip xtensa_mx_irq_chip = {
    144	.name		= "xtensa-mx",
    145	.irq_enable	= xtensa_mx_irq_enable,
    146	.irq_disable	= xtensa_mx_irq_disable,
    147	.irq_mask	= xtensa_mx_irq_mask,
    148	.irq_unmask	= xtensa_mx_irq_unmask,
    149	.irq_ack	= xtensa_mx_irq_ack,
    150	.irq_retrigger	= xtensa_mx_irq_retrigger,
    151	.irq_set_affinity = xtensa_mx_irq_set_affinity,
    152};
    153
    154static void __init xtensa_mx_init_common(struct irq_domain *root_domain)
    155{
    156	unsigned int i;
    157
    158	irq_set_default_host(root_domain);
    159	secondary_init_irq();
    160
    161	/* Initialize default IRQ routing to CPU 0 */
    162	for (i = 0; i < XCHAL_NUM_EXTINTERRUPTS; ++i)
    163		set_er(1, MIROUT(i));
    164}
    165
    166int __init xtensa_mx_init_legacy(struct device_node *interrupt_parent)
    167{
    168	struct irq_domain *root_domain =
    169		irq_domain_add_legacy(NULL, NR_IRQS - 1, 1, 0,
    170				&xtensa_mx_irq_domain_ops,
    171				&xtensa_mx_irq_chip);
    172	xtensa_mx_init_common(root_domain);
    173	return 0;
    174}
    175
    176static int __init xtensa_mx_init(struct device_node *np,
    177		struct device_node *interrupt_parent)
    178{
    179	struct irq_domain *root_domain =
    180		irq_domain_add_linear(np, NR_IRQS, &xtensa_mx_irq_domain_ops,
    181				&xtensa_mx_irq_chip);
    182	xtensa_mx_init_common(root_domain);
    183	return 0;
    184}
    185IRQCHIP_DECLARE(xtensa_mx_irq_chip, "cdns,xtensa-mx", xtensa_mx_init);