irqchip: atmel-aic: Add atmel AIC/AIC5 drivers

Add AIC (Advanced Interrupt Controller) and AIC5 (AIC5 is an evolution of
the AIC block) drivers.
Put common code in irq-atmel-aic-common.c/.h so that both driver can access
shared functions (this will ease maintenance).

These drivers are only compatible with dt enabled board and replace the
old implementation found in arch/arm/mach-at91/irq.c.

Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Link: https://lkml.kernel.org/r/1405012462-766-4-git-send-email-boris.brezillon@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

1 files changed, 341 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-atmel-aic5.c b/drivers/irqchip/irq-atmel-aic5.c
new file mode 100644
index 000000000000..c9c753adc15d
--- /dev/null
+++ b/drivers/irqchip/irq-atmel-aic5.c
@@ -0,0 +1,341 @@
+/*
+ * Atmel AT91 AIC5 (Advanced Interrupt Controller) driver
+ *
+ *  Copyright (C) 2004 SAN People
+ *  Copyright (C) 2004 ATMEL
+ *  Copyright (C) Rick Bronson
+ *  Copyright (C) 2014 Free Electrons
+ *
+ *  Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
+ *
+ * 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 <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/bitmap.h>
+#include <linux/types.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+
+#include <asm/exception.h>
+#include <asm/mach/irq.h>
+
+#include "irq-atmel-aic-common.h"
+#include "irqchip.h"
+
+/* Number of irq lines managed by AIC */
+#define NR_AIC5_IRQS	128
+
+#define AT91_AIC5_SSR		0x0
+#define AT91_AIC5_INTSEL_MSK	(0x7f << 0)
+
+#define AT91_AIC5_SMR			0x4
+
+#define AT91_AIC5_SVR			0x8
+#define AT91_AIC5_IVR			0x10
+#define AT91_AIC5_FVR			0x14
+#define AT91_AIC5_ISR			0x18
+
+#define AT91_AIC5_IPR0			0x20
+#define AT91_AIC5_IPR1			0x24
+#define AT91_AIC5_IPR2			0x28
+#define AT91_AIC5_IPR3			0x2c
+#define AT91_AIC5_IMR			0x30
+#define AT91_AIC5_CISR			0x34
+
+#define AT91_AIC5_IECR			0x40
+#define AT91_AIC5_IDCR			0x44
+#define AT91_AIC5_ICCR			0x48
+#define AT91_AIC5_ISCR			0x4c
+#define AT91_AIC5_EOICR			0x38
+#define AT91_AIC5_SPU			0x3c
+#define AT91_AIC5_DCR			0x6c
+
+#define AT91_AIC5_FFER			0x50
+#define AT91_AIC5_FFDR			0x54
+#define AT91_AIC5_FFSR			0x58
+
+static struct irq_domain *aic5_domain;
+
+static asmlinkage void __exception_irq_entry
+aic5_handle(struct pt_regs *regs)
+{
+	struct irq_domain_chip_generic *dgc = aic5_domain->gc;
+	struct irq_chip_generic *gc = dgc->gc[0];
+	u32 irqnr;
+	u32 irqstat;
+
+	irqnr = irq_reg_readl(gc->reg_base + AT91_AIC5_IVR);
+	irqstat = irq_reg_readl(gc->reg_base + AT91_AIC5_ISR);
+
+	irqnr = irq_find_mapping(aic5_domain, irqnr);
+
+	if (!irqstat)
+		irq_reg_writel(0, gc->reg_base + AT91_AIC5_EOICR);
+	else
+		handle_IRQ(irqnr, regs);
+}
+
+static void aic5_mask(struct irq_data *d)
+{
+	struct irq_domain *domain = d->domain;
+	struct irq_domain_chip_generic *dgc = domain->gc;
+	struct irq_chip_generic *gc = dgc->gc[0];
+
+	/* Disable interrupt on AIC5 */
+	irq_gc_lock(gc);
+	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
+	irq_reg_writel(1, gc->reg_base + AT91_AIC5_IDCR);
+	gc->mask_cache &= ~d->mask;
+	irq_gc_unlock(gc);
+}
+
+static void aic5_unmask(struct irq_data *d)
+{
+	struct irq_domain *domain = d->domain;
+	struct irq_domain_chip_generic *dgc = domain->gc;
+	struct irq_chip_generic *gc = dgc->gc[0];
+
+	/* Enable interrupt on AIC5 */
+	irq_gc_lock(gc);
+	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
+	irq_reg_writel(1, gc->reg_base + AT91_AIC5_IECR);
+	gc->mask_cache |= d->mask;
+	irq_gc_unlock(gc);
+}
+
+static int aic5_retrigger(struct irq_data *d)
+{
+	struct irq_domain *domain = d->domain;
+	struct irq_domain_chip_generic *dgc = domain->gc;
+	struct irq_chip_generic *gc = dgc->gc[0];
+
+	/* Enable interrupt on AIC5 */
+	irq_gc_lock(gc);
+	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
+	irq_reg_writel(1, gc->reg_base + AT91_AIC5_ISCR);
+	irq_gc_unlock(gc);
+
+	return 0;
+}
+
+static int aic5_set_type(struct irq_data *d, unsigned type)
+{
+	struct irq_domain *domain = d->domain;
+	struct irq_domain_chip_generic *dgc = domain->gc;
+	struct irq_chip_generic *gc = dgc->gc[0];
+	unsigned int smr;
+	int ret;
+
+	irq_gc_lock(gc);
+	irq_reg_writel(d->hwirq, gc->reg_base + AT91_AIC5_SSR);
+	smr = irq_reg_readl(gc->reg_base + AT91_AIC5_SMR);
+	ret = aic_common_set_type(d, type, &smr);
+	if (!ret)
+		irq_reg_writel(smr, gc->reg_base + AT91_AIC5_SMR);
+	irq_gc_unlock(gc);
+
+	return ret;
+}
+
+#ifdef CONFIG_PM
+static void aic5_suspend(struct irq_data *d)
+{
+	struct irq_domain *domain = d->domain;
+	struct irq_domain_chip_generic *dgc = domain->gc;
+	struct irq_chip_generic *bgc = dgc->gc[0];
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+	int i;
+	u32 mask;
+
+	irq_gc_lock(bgc);
+	for (i = 0; i < dgc->irqs_per_chip; i++) {
+		mask = 1 << i;
+		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
+			continue;
+
+		irq_reg_writel(i + gc->irq_base,
+			       bgc->reg_base + AT91_AIC5_SSR);
+		if (mask & gc->wake_active)
+			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IECR);
+		else
+			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IDCR);
+	}
+	irq_gc_unlock(bgc);
+}
+
+static void aic5_resume(struct irq_data *d)
+{
+	struct irq_domain *domain = d->domain;
+	struct irq_domain_chip_generic *dgc = domain->gc;
+	struct irq_chip_generic *bgc = dgc->gc[0];
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+	int i;
+	u32 mask;
+
+	irq_gc_lock(bgc);
+	for (i = 0; i < dgc->irqs_per_chip; i++) {
+		mask = 1 << i;
+		if ((mask & gc->mask_cache) == (mask & gc->wake_active))
+			continue;
+
+		irq_reg_writel(i + gc->irq_base,
+			       bgc->reg_base + AT91_AIC5_SSR);
+		if (mask & gc->mask_cache)
+			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IECR);
+		else
+			irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IDCR);
+	}
+	irq_gc_unlock(bgc);
+}
+
+static void aic5_pm_shutdown(struct irq_data *d)
+{
+	struct irq_domain *domain = d->domain;
+	struct irq_domain_chip_generic *dgc = domain->gc;
+	struct irq_chip_generic *bgc = dgc->gc[0];
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+	int i;
+
+	irq_gc_lock(bgc);
+	for (i = 0; i < dgc->irqs_per_chip; i++) {
+		irq_reg_writel(i + gc->irq_base,
+			       bgc->reg_base + AT91_AIC5_SSR);
+		irq_reg_writel(1, bgc->reg_base + AT91_AIC5_IDCR);
+		irq_reg_writel(1, bgc->reg_base + AT91_AIC5_ICCR);
+	}
+	irq_gc_unlock(bgc);
+}
+#else
+#define aic5_suspend		NULL
+#define aic5_resume		NULL
+#define aic5_pm_shutdown	NULL
+#endif /* CONFIG_PM */
+
+static void __init aic5_hw_init(struct irq_domain *domain)
+{
+	struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
+	int i;
+
+	/*
+	 * Perform 8 End Of Interrupt Command to make sure AIC
+	 * will not Lock out nIRQ
+	 */
+	for (i = 0; i < 8; i++)
+		irq_reg_writel(0, gc->reg_base + AT91_AIC5_EOICR);
+
+	/*
+	 * Spurious Interrupt ID in Spurious Vector Register.
+	 * When there is no current interrupt, the IRQ Vector Register
+	 * reads the value stored in AIC_SPU
+	 */
+	irq_reg_writel(0xffffffff, gc->reg_base + AT91_AIC5_SPU);
+
+	/* No debugging in AIC: Debug (Protect) Control Register */
+	irq_reg_writel(0, gc->reg_base + AT91_AIC5_DCR);
+
+	/* Disable and clear all interrupts initially */
+	for (i = 0; i < domain->revmap_size; i++) {
+		irq_reg_writel(i, gc->reg_base + AT91_AIC5_SSR);
+		irq_reg_writel(i, gc->reg_base + AT91_AIC5_SVR);
+		irq_reg_writel(1, gc->reg_base + AT91_AIC5_IDCR);
+		irq_reg_writel(1, gc->reg_base + AT91_AIC5_ICCR);
+	}
+}
+
+static int aic5_irq_domain_xlate(struct irq_domain *d,
+				 struct device_node *ctrlr,
+				 const u32 *intspec, unsigned int intsize,
+				 irq_hw_number_t *out_hwirq,
+				 unsigned int *out_type)
+{
+	struct irq_domain_chip_generic *dgc = d->gc;
+	struct irq_chip_generic *gc;
+	unsigned smr;
+	int ret;
+
+	if (!dgc)
+		return -EINVAL;
+
+	ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
+					  out_hwirq, out_type);
+	if (ret)
+		return ret;
+
+	gc = dgc->gc[0];
+
+	irq_gc_lock(gc);
+	irq_reg_writel(*out_hwirq, gc->reg_base + AT91_AIC5_SSR);
+	smr = irq_reg_readl(gc->reg_base + AT91_AIC5_SMR);
+	ret = aic_common_set_priority(intspec[2], &smr);
+	if (!ret)
+		irq_reg_writel(intspec[2] | smr, gc->reg_base + AT91_AIC5_SMR);
+	irq_gc_unlock(gc);
+
+	return ret;
+}
+
+static const struct irq_domain_ops aic5_irq_ops = {
+	.map	= irq_map_generic_chip,
+	.xlate	= aic5_irq_domain_xlate,
+};
+
+static int __init aic5_of_init(struct device_node *node,
+			       struct device_node *parent,
+			       int nirqs)
+{
+	struct irq_chip_generic *gc;
+	struct irq_domain *domain;
+	int nchips;
+	int i;
+
+	if (nirqs > NR_AIC5_IRQS)
+		return -EINVAL;
+
+	if (aic5_domain)
+		return -EEXIST;
+
+	domain = aic_common_of_init(node, &aic5_irq_ops, "atmel-aic5",
+				    nirqs);
+	if (IS_ERR(domain))
+		return PTR_ERR(domain);
+
+	aic5_domain = domain;
+	nchips = aic5_domain->revmap_size / 32;
+	for (i = 0; i < nchips; i++) {
+		gc = irq_get_domain_generic_chip(domain, i * 32);
+
+		gc->chip_types[0].regs.eoi = AT91_AIC5_EOICR;
+		gc->chip_types[0].chip.irq_mask = aic5_mask;
+		gc->chip_types[0].chip.irq_unmask = aic5_unmask;
+		gc->chip_types[0].chip.irq_retrigger = aic5_retrigger;
+		gc->chip_types[0].chip.irq_set_type = aic5_set_type;
+		gc->chip_types[0].chip.irq_suspend = aic5_suspend;
+		gc->chip_types[0].chip.irq_resume = aic5_resume;
+		gc->chip_types[0].chip.irq_pm_shutdown = aic5_pm_shutdown;
+	}
+
+	aic5_hw_init(domain);
+	set_handle_irq(aic5_handle);
+
+	return 0;
+}
+
+#define NR_SAMA5D3_IRQS		50
+
+static int __init sama5d3_aic5_of_init(struct device_node *node,
+				       struct device_node *parent)
+{
+	return aic5_of_init(node, parent, NR_SAMA5D3_IRQS);
+}
+IRQCHIP_DECLARE(sama5d3_aic5, "atmel,sama5d3-aic", sama5d3_aic5_of_init);