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-sun4i.c (6026B)


      1/*
      2 * Allwinner A1X SoCs IRQ chip driver.
      3 *
      4 * Copyright (C) 2012 Maxime Ripard
      5 *
      6 * Maxime Ripard <maxime.ripard@free-electrons.com>
      7 *
      8 * Based on code from
      9 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
     10 * Benn Huang <benn@allwinnertech.com>
     11 *
     12 * This file is licensed under the terms of the GNU General Public
     13 * License version 2.  This program is licensed "as is" without any
     14 * warranty of any kind, whether express or implied.
     15 */
     16
     17#include <linux/io.h>
     18#include <linux/irq.h>
     19#include <linux/irqchip.h>
     20#include <linux/of.h>
     21#include <linux/of_address.h>
     22#include <linux/of_irq.h>
     23
     24#include <asm/exception.h>
     25
     26#define SUN4I_IRQ_VECTOR_REG		0x00
     27#define SUN4I_IRQ_PROTECTION_REG	0x08
     28#define SUN4I_IRQ_NMI_CTRL_REG		0x0c
     29#define SUN4I_IRQ_PENDING_REG(x)	(0x10 + 0x4 * x)
     30#define SUN4I_IRQ_FIQ_PENDING_REG(x)	(0x20 + 0x4 * x)
     31#define SUN4I_IRQ_ENABLE_REG(data, x)	((data)->enable_reg_offset + 0x4 * x)
     32#define SUN4I_IRQ_MASK_REG(data, x)	((data)->mask_reg_offset + 0x4 * x)
     33#define SUN4I_IRQ_ENABLE_REG_OFFSET	0x40
     34#define SUN4I_IRQ_MASK_REG_OFFSET	0x50
     35#define SUNIV_IRQ_ENABLE_REG_OFFSET	0x20
     36#define SUNIV_IRQ_MASK_REG_OFFSET	0x30
     37
     38struct sun4i_irq_chip_data {
     39	void __iomem *irq_base;
     40	struct irq_domain *irq_domain;
     41	u32 enable_reg_offset;
     42	u32 mask_reg_offset;
     43};
     44
     45static struct sun4i_irq_chip_data *irq_ic_data;
     46
     47static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs);
     48
     49static void sun4i_irq_ack(struct irq_data *irqd)
     50{
     51	unsigned int irq = irqd_to_hwirq(irqd);
     52
     53	if (irq != 0)
     54		return; /* Only IRQ 0 / the ENMI needs to be acked */
     55
     56	writel(BIT(0), irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(0));
     57}
     58
     59static void sun4i_irq_mask(struct irq_data *irqd)
     60{
     61	unsigned int irq = irqd_to_hwirq(irqd);
     62	unsigned int irq_off = irq % 32;
     63	int reg = irq / 32;
     64	u32 val;
     65
     66	val = readl(irq_ic_data->irq_base +
     67			SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
     68	writel(val & ~(1 << irq_off),
     69	       irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
     70}
     71
     72static void sun4i_irq_unmask(struct irq_data *irqd)
     73{
     74	unsigned int irq = irqd_to_hwirq(irqd);
     75	unsigned int irq_off = irq % 32;
     76	int reg = irq / 32;
     77	u32 val;
     78
     79	val = readl(irq_ic_data->irq_base +
     80			SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
     81	writel(val | (1 << irq_off),
     82	       irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
     83}
     84
     85static struct irq_chip sun4i_irq_chip = {
     86	.name		= "sun4i_irq",
     87	.irq_eoi	= sun4i_irq_ack,
     88	.irq_mask	= sun4i_irq_mask,
     89	.irq_unmask	= sun4i_irq_unmask,
     90	.flags		= IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED,
     91};
     92
     93static int sun4i_irq_map(struct irq_domain *d, unsigned int virq,
     94			 irq_hw_number_t hw)
     95{
     96	irq_set_chip_and_handler(virq, &sun4i_irq_chip, handle_fasteoi_irq);
     97	irq_set_probe(virq);
     98
     99	return 0;
    100}
    101
    102static const struct irq_domain_ops sun4i_irq_ops = {
    103	.map = sun4i_irq_map,
    104	.xlate = irq_domain_xlate_onecell,
    105};
    106
    107static int __init sun4i_of_init(struct device_node *node,
    108				struct device_node *parent)
    109{
    110	irq_ic_data->irq_base = of_iomap(node, 0);
    111	if (!irq_ic_data->irq_base)
    112		panic("%pOF: unable to map IC registers\n",
    113			node);
    114
    115	/* Disable all interrupts */
    116	writel(0, irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, 0));
    117	writel(0, irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, 1));
    118	writel(0, irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, 2));
    119
    120	/* Unmask all the interrupts, ENABLE_REG(x) is used for masking */
    121	writel(0, irq_ic_data->irq_base + SUN4I_IRQ_MASK_REG(irq_ic_data, 0));
    122	writel(0, irq_ic_data->irq_base + SUN4I_IRQ_MASK_REG(irq_ic_data, 1));
    123	writel(0, irq_ic_data->irq_base + SUN4I_IRQ_MASK_REG(irq_ic_data, 2));
    124
    125	/* Clear all the pending interrupts */
    126	writel(0xffffffff, irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(0));
    127	writel(0xffffffff, irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(1));
    128	writel(0xffffffff, irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(2));
    129
    130	/* Enable protection mode */
    131	writel(0x01, irq_ic_data->irq_base + SUN4I_IRQ_PROTECTION_REG);
    132
    133	/* Configure the external interrupt source type */
    134	writel(0x00, irq_ic_data->irq_base + SUN4I_IRQ_NMI_CTRL_REG);
    135
    136	irq_ic_data->irq_domain = irq_domain_add_linear(node, 3 * 32,
    137						 &sun4i_irq_ops, NULL);
    138	if (!irq_ic_data->irq_domain)
    139		panic("%pOF: unable to create IRQ domain\n", node);
    140
    141	set_handle_irq(sun4i_handle_irq);
    142
    143	return 0;
    144}
    145
    146static int __init sun4i_ic_of_init(struct device_node *node,
    147				   struct device_node *parent)
    148{
    149	irq_ic_data = kzalloc(sizeof(struct sun4i_irq_chip_data), GFP_KERNEL);
    150	if (!irq_ic_data)
    151		return -ENOMEM;
    152
    153	irq_ic_data->enable_reg_offset = SUN4I_IRQ_ENABLE_REG_OFFSET;
    154	irq_ic_data->mask_reg_offset = SUN4I_IRQ_MASK_REG_OFFSET;
    155
    156	return sun4i_of_init(node, parent);
    157}
    158
    159IRQCHIP_DECLARE(allwinner_sun4i_ic, "allwinner,sun4i-a10-ic", sun4i_ic_of_init);
    160
    161static int __init suniv_ic_of_init(struct device_node *node,
    162				   struct device_node *parent)
    163{
    164	irq_ic_data = kzalloc(sizeof(struct sun4i_irq_chip_data), GFP_KERNEL);
    165	if (!irq_ic_data)
    166		return -ENOMEM;
    167
    168	irq_ic_data->enable_reg_offset = SUNIV_IRQ_ENABLE_REG_OFFSET;
    169	irq_ic_data->mask_reg_offset = SUNIV_IRQ_MASK_REG_OFFSET;
    170
    171	return sun4i_of_init(node, parent);
    172}
    173
    174IRQCHIP_DECLARE(allwinner_sunvi_ic, "allwinner,suniv-f1c100s-ic",
    175		suniv_ic_of_init);
    176
    177static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs)
    178{
    179	u32 hwirq;
    180
    181	/*
    182	 * hwirq == 0 can mean one of 3 things:
    183	 * 1) no more irqs pending
    184	 * 2) irq 0 pending
    185	 * 3) spurious irq
    186	 * So if we immediately get a reading of 0, check the irq-pending reg
    187	 * to differentiate between 2 and 3. We only do this once to avoid
    188	 * the extra check in the common case of 1 happening after having
    189	 * read the vector-reg once.
    190	 */
    191	hwirq = readl(irq_ic_data->irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
    192	if (hwirq == 0 &&
    193		  !(readl(irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(0)) &
    194			  BIT(0)))
    195		return;
    196
    197	do {
    198		generic_handle_domain_irq(irq_ic_data->irq_domain, hwirq);
    199		hwirq = readl(irq_ic_data->irq_base +
    200				SUN4I_IRQ_VECTOR_REG) >> 2;
    201	} while (hwirq != 0);
    202}