/*
* Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
* Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de>
* Add Alphascale ASM9260 support.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/stmp_device.h>
#include <asm/exception.h>
#include "alphascale_asm9260-icoll.h"
/*
* this device provide 4 offsets for each register:
* 0x0 - plain read write mode
* 0x4 - set mode, OR logic.
* 0x8 - clr mode, XOR logic.
* 0xc - togle mode.
*/
#define SET_REG 4
#define CLR_REG 8
#define HW_ICOLL_VECTOR 0x0000
#define HW_ICOLL_LEVELACK 0x0010
#define HW_ICOLL_CTRL 0x0020
#define HW_ICOLL_STAT_OFFSET 0x0070
#define HW_ICOLL_INTERRUPT0 0x0120
#define HW_ICOLL_INTERRUPTn(n) ((n) * 0x10)
#define BM_ICOLL_INTR_ENABLE BIT(2)
#define BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0 0x1
#define ICOLL_NUM_IRQS 128
enum icoll_type {
ICOLL,
ASM9260_ICOLL,
};
struct icoll_priv {
void __iomem *vector;
void __iomem *levelack;
void __iomem *ctrl;
void __iomem *stat;
void __iomem *intr;
void __iomem *clear;
enum icoll_type type;
};
static struct icoll_priv icoll_priv;
static struct irq_domain *icoll_domain;
/* calculate bit offset depending on number of intterupt per register */
static u32 icoll_intr_bitshift(struct irq_data *d, u32 bit)
{
/*
* mask lower part of hwirq to convert it
* in 0, 1, 2 or 3 and then multiply it by 8 (or shift by 3)
*/
return bit << ((d->hwirq & 3) << 3);
}
/* calculate mem offset depending on number of intterupt per register */
static void __iomem *icoll_intr_reg(struct irq_data *d)
{
/* offset = hwirq / intr_per_reg * 0x10 */
return icoll_priv.intr + ((d->hwirq >> 2) * 0x10);
}
static void icoll_ack_irq(struct irq_data *d)
{
/*
* The Interrupt Collector is able to prioritize irqs.
* Currently only level 0 is used. So acking can use
* BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0 unconditionally.
*/
__raw_writel(BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0,
icoll_priv.levelack);
}
static void icoll_mask_irq(struct irq_data *d)
{
__raw_writel(BM_ICOLL_INTR_ENABLE,
icoll_priv.intr + CLR_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
}
static void icoll_unmask_irq(struct irq_data *d)
{
__raw_writel(BM_ICOLL_INTR_ENABLE,
icoll_priv.intr + SET_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
}
static void asm9260_mask_irq(struct irq_data *d)
{
__raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
icoll_intr_reg(d) + CLR_REG);
}
static void asm9260_unmask_irq(struct irq_data *d)
{
__raw_writel(ASM9260_BM_CLEAR_BIT(d->hwirq),
icoll_priv.clear +
ASM9260_HW_ICOLL_CLEARn(d->hwirq));
__raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
icoll_intr_reg(d) + SET_REG);
}
static struct irq_chip mxs_icoll_chip = {
.irq_ack = icoll_ack_irq,
.irq_mask = icoll_mask_irq,
.irq_unmask = icoll_unmask_irq,
.flags = IRQCHIP_MASK_ON_SUSPEND |
IRQCHIP_SKIP_SET_WAKE,
};
static struct irq_chip asm9260_icoll_chip = {
.irq_ack = icoll_ack_irq,
.irq_mask = asm9260_mask_irq,
.irq_unmask = asm9260_unmask_irq,
.flags = IRQCHIP_MASK_ON_SUSPEND |
IRQCHIP_SKIP_SET_WAKE,
};
asmlinkage void __exception_irq_entry icoll_handle_irq(struct pt_regs *regs)
{
u32 irqnr;
irqnr = __raw_readl(icoll_priv.stat);
__raw_writel(irqnr, icoll_priv.vector);
handle_domain_irq(icoll_domain, irqnr, regs);
}
static int icoll_irq_domain_map(struct irq_domain *d, unsigned int virq,
irq_hw_number_t hw)
{
struct irq_chip *chip;
if (icoll_priv.type == ICOLL)
chip = &mxs_icoll_chip;
else
chip = &asm9260_icoll_chip;
irq_set_chip_and_handler(virq, chip, handle_level_irq);
return 0;
}
static const struct irq_domain_ops icoll_irq_domain_ops = {
.map = icoll_irq_domain_map,
.xlate = irq_domain_xlate_onecell,
};
static void __init icoll_add_domain(struct device_node *np,
int num)
{
icoll_domain = irq_domain_add_linear(np, num,
&icoll_irq_domain_ops, NULL);
if (!icoll_domain)
panic("%s: unable to create irq domain", np->full_name);
}
static void __iomem * __init icoll_init_iobase(struct device_node *np)
{
void __iomem *icoll_base;
icoll_base = of_io_request_and_map(np, 0, np->name);
if (IS_ERR(icoll_base))
panic("%s: unable to map resource", np->full_name);
return icoll_base;
}
static int __init icoll_of_init(struct device_node *np,
struct device_node *interrupt_parent)
{
void __iomem *icoll_base;
icoll_priv.type = ICOLL;
icoll_base = icoll_init_iobase(np);
icoll_priv.vector = icoll_base + HW_ICOLL_VECTOR;
icoll_priv.levelack = icoll_base + HW_ICOLL_LEVELACK;
icoll_priv.ctrl = icoll_base + HW_ICOLL_CTRL;
icoll_priv.stat = icoll_base + HW_ICOLL_STAT_OFFSET;
icoll_priv.intr = icoll_base + HW_ICOLL_INTERRUPT0;
icoll_priv.clear = NULL;
/*
* Interrupt Collector reset, which initializes the priority
* for each irq to level 0.
*/
stmp_reset_block(icoll_priv.ctrl);
icoll_add_domain(np, ICOLL_NUM_IRQS);
return 0;
}
IRQCHIP_DECLARE(mxs, "fsl,icoll", icoll_of_init);
static int __init asm9260_of_init(struct device_node *np,
struct device_node *interrupt_parent)
{
void __iomem *icoll_base;
int i;
icoll_priv.type = ASM9260_ICOLL;
icoll_base = icoll_init_iobase(np);
icoll_priv.vector = icoll_base + ASM9260_HW_ICOLL_VECTOR;
icoll_priv.levelack = icoll_base + ASM9260_HW_ICOLL_LEVELACK;
icoll_priv.ctrl = icoll_base + ASM9260_HW_ICOLL_CTRL;
icoll_priv.stat = icoll_base + ASM9260_HW_ICOLL_STAT_OFFSET;
icoll_priv.intr = icoll_base + ASM9260_HW_ICOLL_INTERRUPT0;
icoll_priv.clear = icoll_base + ASM9260_HW_ICOLL_CLEAR0;
writel_relaxed(ASM9260_BM_CTRL_IRQ_ENABLE,
icoll_priv.ctrl);
/*
* ASM9260 don't provide reset bit. So, we need to set level 0
* manually.
*/
for (i = 0; i < 16 * 0x10; i += 0x10)
writel(0, icoll_priv.intr + i);
icoll_add_domain(np, ASM9260_NUM_IRQS);
set_handle_irq(icoll_handle_irq);
return 0;
}
IRQCHIP_DECLARE(asm9260, "alphascale,asm9260-icoll", asm9260_of_init);