irqchip: s3c24xx: add devicetree support
From: Heiko Stuebner <heiko@...> Date: Sat, 16 Mar 2013 16:03:47 +0100
Commit-Message
Add the necessary code to initialize the interrupt controller thru devicetree data using the irqchip infrastructure. Signed-off-by: Heiko Stuebner <heiko@...>
Patch-Comment
.../interrupt-controller/samsung,s3c24xx-irq.txt | 53 +++++ drivers/irqchip/irq-s3c24xx.c | 231 +++++++++++++++++++- 2 files changed, 278 insertions(+), 6 deletions(-) create mode 100644 Documentation/devicetree/bindings/interrupt-controller/samsung,s3c24xx-irq.txt
Statistics
- 278 lines added
- 6 lines removed
Changes
Documentation/devicetree/bindings/interrupt-controller/samsung,s3c24xx-irq.txt
new file mode 100644
index 0000000..c54c5a9
@@ -0,0 +1,53 @@
+Samsung S3C24XX Interrupt Controllers
+
+The S3C24XX SoCs contain a custom set of interrupt controllers providing a
+varying number of interrupt sources. The set consists of a main- and sub-
+controller and on newer SoCs even a second main controller.
+
+Required properties:
+- compatible: Compatible property value should be "samsung,s3c2410-irq"
+ for machines before s3c2416 and "samsung,s3c2416-irq" for s3c2416 and later.
+
+- reg: Physical base address of the controller and length of memory mapped
+ region.
+
+- interrupt-controller : Identifies the node as an interrupt controller
+
+- #interrupt-cells : Specifies the number of cells needed to encode an
+ interrupt source. The value shall be 4 and interrupt descriptor shall
+ have the following format:
+ <ctrl_num parent_irq ctrl_irq type>
+
+ ctrl_num contains the controller to use:
+ - 0 ... main controller
+ - 1 ... sub controller
+ - 2 ... second main controller on s3c2416 and s3c2450
+ parent_irq contains the parent bit in the main controller and will be
+ ignored in main controllers
+ ctrl_irq contains the interrupt bit of the controller
+ type contains the trigger type to use
+
+Example:
+
+ interrupt-controller@4a000000 {
+ compatible = "samsung,s3c2410-irq";
+ reg = <0x4a000000 0x100>;
+ interrupt-controller;
+ #interrupt-cells=<4>;
+ };
+
+ [...]
+
+ serial@50000000 {
+ compatible = "samsung,s3c2410-uart";
+ reg = <0x50000000 0x4000>;
+ interrupt-parent = <&subintc>;
+ interrupts = <1 28 0 4>, <1 28 1 4>;
+ };
+
+ rtc@57000000 {
+ compatible = "samsung,s3c2410-rtc";
+ reg = <0x57000000 0x100>;
+ interrupt-parent = <&intc>;
+ interrupts = <0 30 0 3>, <0 8 0 3>;
+ };
------------------------ drivers/irqchip/irq-s3c24xx.c -------------------------
index 02b82db..5e40b34 100644
@@ -25,6 +25,9 @@
#include <linux/ioport.h>
#include <linux/device.h>
#include <linux/irqdomain.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
#include <asm/exception.h>
#include <asm/mach/irq.h>
@@ -36,6 +39,8 @@
#include <plat/regs-irqtype.h>
#include <plat/pm.h>
+#include "irqchip.h"
+
#define S3C_IRQTYPE_NONE 0
#define S3C_IRQTYPE_EINT 1
#define S3C_IRQTYPE_EDGE 2
@@ -94,7 +99,10 @@ static void s3c_irq_mask(struct irq_data *data)
if (parent_intc) {
parent_data = &parent_intc->irqs[irq_data->parent_irq];
+ /* check to see if we need to mask the parent IRQ
+ * The parent_irq is always in main_intc, so the hwirq
+ * for find_mapping does not need an offset in any case.
+ */
if ((mask & parent_data->sub_bits) == parent_data->sub_bits) {
irqno = irq_find_mapping(parent_intc->domain,
irq_data->parent_irq);
@@ -294,10 +302,18 @@ static void s3c_irq_demux(unsigned int irq, struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
struct s3c_irq_data *irq_data = irq_desc_get_chip_data(desc);
+ struct s3c_irq_intc *intc = irq_data->intc;
struct s3c_irq_intc *sub_intc = irq_data->sub_intc;
unsigned long src;
unsigned long msk;
unsigned int n;
+ unsigned int offset;
+
+ /* we're using individual domains for the non-dt case
+ * and one big domain for the dt case where the subintc
+ * starts at hwirq number 32.
+ */
+ offset = (intc->domain->of_node) ? 32 : 0;
chained_irq_enter(chip, desc);
@@ -310,14 +326,15 @@ static void s3c_irq_demux(unsigned int irq, struct irq_desc *desc)
while (src) {
n = __ffs(src);
src &= ~(1 << n);
+ irq = irq_find_mapping(sub_intc->domain, offset + n);
+ generic_handle_irq(irq);
}
chained_irq_exit(chip, desc);
}
static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc,
+ struct pt_regs *regs, int intc_offset)
{
int pnd;
int offset;
@@ -327,6 +344,10 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc,
if (!pnd)
return false;
+ /* non-dt machines use individual domains */
+ if (!intc->domain->of_node)
+ intc_offset = 0;
+
/* We have a problem that the INTOFFSET register does not always
* show one interrupt. Occasionally we get two interrupts through
* the prioritiser, and this causes the INTOFFSET register to show
@@ -343,7 +364,7 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc,
if (!(pnd & (1 << offset)))
offset = __ffs(pnd);
+ irq = irq_find_mapping(intc->domain, intc_offset + offset);
handle_IRQ(irq, regs);
return true;
}
@@ -352,11 +373,11 @@ asmlinkage void __exception_irq_entry s3c24xx_handle_irq(struct pt_regs *regs)
{
do {
if (likely(s3c_intc[0]))
+ if (s3c24xx_handle_intc(s3c_intc[0], regs, 0))
continue;
if (s3c_intc[2])
+ if (s3c24xx_handle_intc(s3c_intc[2], regs, 64))
continue;
break;
@@ -1134,3 +1155,201 @@ void __init s3c2443_init_irq(void)
s3c_intc[0], 0x4a000018);
}
#endif
+
+#ifdef CONFIG_OF
+static int s3c24xx_irq_map_of(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ unsigned int ctrl_num = hw / 32;
+ unsigned int intc_hw = hw % 32;
+ struct s3c_irq_intc *intc = s3c_intc[ctrl_num];
+ struct s3c_irq_intc *parent_intc = intc->parent;
+ struct s3c_irq_data *irq_data = &intc->irqs[intc_hw];
+
+ /* attach controller pointer to irq_data */
+ irq_data->intc = intc;
+ irq_data->offset = intc_hw;
+
+ if (!parent_intc)
+ irq_set_chip_and_handler(virq, &s3c_irq_chip, handle_edge_irq);
+ else
+ irq_set_chip_and_handler(virq, &s3c_irq_level_chip,
+ handle_edge_irq);
+
+ irq_set_chip_data(virq, irq_data);
+
+ set_irq_flags(virq, IRQF_VALID);
+
+ return 0;
+}
+
+/* Translate our of irq notation
+ * format: <ctrl_num ctrl_irq parent_irq type>
+ */
+static int s3c24xx_irq_xlate_of(struct irq_domain *d, struct device_node *n,
+ const u32 *intspec, unsigned int intsize,
+ irq_hw_number_t *out_hwirq, unsigned int *out_type)
+{
+ struct s3c_irq_intc *intc;
+ struct s3c_irq_intc *parent_intc;
+ struct s3c_irq_data *irq_data;
+ struct s3c_irq_data *parent_irq_data;
+ int irqno;
+
+ if (WARN_ON(intsize < 4))
+ return -EINVAL;
+
+ if (intspec[0] > 2 || !s3c_intc[intspec[0]]) {
+ pr_err("controller number %d invalid\n", intspec[0]);
+ return -EINVAL;
+ }
+ intc = s3c_intc[intspec[0]];
+
+ *out_hwirq = intspec[0] * 32 + intspec[2];
+ *out_type = intspec[3] & IRQ_TYPE_SENSE_MASK;
+
+ parent_intc = intc->parent;
+ if (parent_intc) {
+ irq_data = &intc->irqs[intspec[2]];
+ irq_data->parent_irq = intspec[1];
+ parent_irq_data = &parent_intc->irqs[irq_data->parent_irq];
+ parent_irq_data->sub_intc = intc;
+ parent_irq_data->sub_bits |= (1UL << intspec[2]);
+
+ /* parent_intc is always s3c_intc[0], so no offset */
+ irqno = irq_create_mapping(parent_intc->domain, intspec[1]);
+ if (irqno < 0) {
+ pr_err("irq: could not map parent interrupt\n");
+ return irqno;
+ }
+
+ irq_set_chained_handler(irqno, s3c_irq_demux);
+ }
+
+ return 0;
+}
+
+static struct irq_domain_ops s3c24xx_irq_ops_of = {
+ .map = s3c24xx_irq_map_of,
+ .xlate = s3c24xx_irq_xlate_of,
+};
+
+struct s3c24xx_irq_of_ctrl {
+ char *name;
+ unsigned long offset;
+ struct s3c_irq_intc **handle;
+ struct s3c_irq_intc **parent;
+ struct irq_domain_ops *ops;
+};
+
+static int __init s3c_init_intc_of(struct device_node *np,
+ struct device_node *interrupt_parent,
+ struct s3c24xx_irq_of_ctrl *s3c_ctrl, int num_ctrl)
+{
+ struct s3c_irq_intc *intc;
+ struct s3c24xx_irq_of_ctrl *ctrl;
+ struct irq_domain *domain;
+ void __iomem *reg_base;
+ int i;
+
+ reg_base = of_iomap(np, 0);
+ if (!reg_base) {
+ pr_err("irq-s3c24xx: could not map irq registers\n");
+ return -EINVAL;
+ }
+
+ domain = irq_domain_add_linear(np, num_ctrl * 32,
+ &s3c24xx_irq_ops_of, NULL);
+ if (!domain) {
+ pr_err("irq: could not create irq-domain\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < num_ctrl; i++) {
+ ctrl = &s3c_ctrl[i];
+
+ pr_debug("irq: found controller %s\n", ctrl->name);
+
+ intc = kzalloc(sizeof(struct s3c_irq_intc), GFP_KERNEL);
+ if (!intc)
+ return -ENOMEM;
+
+ intc->domain = domain;
+ intc->irqs = kzalloc(sizeof(struct s3c_irq_data) * 32,
+ GFP_KERNEL);
+ if (!intc->irqs) {
+ kfree(intc);
+ return -ENOMEM;
+ }
+
+ if (ctrl->parent) {
+ intc->reg_pending = reg_base + ctrl->offset;
+ intc->reg_mask = reg_base + ctrl->offset + 0x4;
+
+ if (*(ctrl->parent)) {
+ intc->parent = *(ctrl->parent);
+ } else {
+ pr_warn("irq: parent of %s missing\n",
+ ctrl->name);
+ kfree(intc->irqs);
+ kfree(intc);
+ continue;
+ }
+ } else {
+ intc->reg_pending = reg_base + ctrl->offset;
+ intc->reg_mask = reg_base + ctrl->offset + 0x08;
+ intc->reg_intpnd = reg_base + ctrl->offset + 0x10;
+ }
+
+ s3c24xx_clear_intc(intc);
+ s3c_intc[i] = intc;
+ }
+
+ set_handle_irq(s3c24xx_handle_irq);
+
+ return 0;
+}
+
+static struct s3c24xx_irq_of_ctrl s3c2410_ctrl[] = {
+ {
+ .name = "intc",
+ .offset = 0,
+ }, {
+ .name = "subintc",
+ .offset = 0x18,
+ .parent = &s3c_intc[0],
+ }
+};
+
+int __init s3c2410_init_intc_of(struct device_node *np,
+ struct device_node *interrupt_parent,
+ struct s3c24xx_irq_of_ctrl *ctrl, int num_ctrl)
+{
+ return s3c_init_intc_of(np, interrupt_parent,
+ s3c2410_ctrl, ARRAY_SIZE(s3c2410_ctrl));
+}
+IRQCHIP_DECLARE(s3c2410_irq, "samsung,s3c2410-irq", s3c2410_init_intc_of);
+
+static struct s3c24xx_irq_of_ctrl s3c2416_ctrl[] = {
+ {
+ .name = "intc",
+ .offset = 0,
+ }, {
+ .name = "subintc",
+ .offset = 0x18,
+ .parent = &s3c_intc[0],
+ }, {
+ .name = "intc2",
+ .offset = 0x40,
+ }
+};
+
+int __init s3c2416_init_intc_of(struct device_node *np,
+ struct device_node *interrupt_parent,
+ struct s3c24xx_irq_of_ctrl *ctrl, int num_ctrl)
+{
+ return s3c_init_intc_of(np, interrupt_parent,
+ s3c2416_ctrl, ARRAY_SIZE(s3c2416_ctrl));
+}
+IRQCHIP_DECLARE(s3c2416_irq, "samsung,s3c2416-irq", s3c2416_init_intc_of);
+#endif