#include <linux/of_irq.h>
#include <linux/slab.h>
#include <linux/irqchip/arm-gic.h>
+#include <linux/irqchip/irq-crossbar.h>
#define IRQ_FREE -1
#define IRQ_RESERVED -2
+#define IRQ_SKIP -3
#define GIC_IRQ_START 32
-/*
+/**
+ * struct crossbar_device - crossbar device description
* @int_max: maximum number of supported interrupts
+ * @safe_map: safe default value to initialize the crossbar
+ * @max_crossbar_sources: Maximum number of crossbar sources
* @irq_map: array of interrupts to crossbar number mapping
* @crossbar_base: crossbar base address
* @register_offsets: offsets for each irq number
+ * @write: register write function pointer
*/
struct crossbar_device {
uint int_max;
+ uint safe_map;
+ uint max_crossbar_sources;
uint *irq_map;
void __iomem *crossbar_base;
int *register_offsets;
- void (*write) (int, int);
+ void (*write)(int, int);
};
static struct crossbar_device *cb;
{
int i;
- for (i = 0; i < cb->int_max; i++)
+ for (i = cb->int_max - 1; i >= 0; i--)
if (cb->irq_map[i] == cb_no)
return i;
{
int i;
- for (i = 0; i < cb->int_max; i++) {
+ for (i = cb->int_max - 1; i >= 0; i--) {
if (cb->irq_map[i] == IRQ_FREE) {
cb->irq_map[i] = cb_no;
return i;
return -ENODEV;
}
+static inline bool needs_crossbar_write(irq_hw_number_t hw)
+{
+ int cb_no;
+
+ if (hw > GIC_IRQ_START) {
+ cb_no = cb->irq_map[hw - GIC_IRQ_START];
+ if (cb_no != IRQ_RESERVED && cb_no != IRQ_SKIP)
+ return true;
+ }
+
+ return false;
+}
+
static int crossbar_domain_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
- cb->write(hw - GIC_IRQ_START, cb->irq_map[hw - GIC_IRQ_START]);
+ if (needs_crossbar_write(hw))
+ cb->write(hw - GIC_IRQ_START, cb->irq_map[hw - GIC_IRQ_START]);
+
return 0;
}
+/**
+ * crossbar_domain_unmap - unmap a crossbar<->irq connection
+ * @d: domain of irq to unmap
+ * @irq: virq number
+ *
+ * We do not maintain a use count of total number of map/unmap
+ * calls for a particular irq to find out if a irq can be really
+ * unmapped. This is because unmap is called during irq_dispose_mapping(irq),
+ * after which irq is anyways unusable. So an explicit map has to be called
+ * after that.
+ */
static void crossbar_domain_unmap(struct irq_domain *d, unsigned int irq)
{
irq_hw_number_t hw = irq_get_irq_data(irq)->hwirq;
- if (hw > GIC_IRQ_START)
+ if (needs_crossbar_write(hw)) {
cb->irq_map[hw - GIC_IRQ_START] = IRQ_FREE;
+ cb->write(hw - GIC_IRQ_START, cb->safe_map);
+ }
}
static int crossbar_domain_xlate(struct irq_domain *d,
unsigned long *out_hwirq,
unsigned int *out_type)
{
- unsigned long ret;
+ int ret;
+ int req_num = intspec[1];
+ int direct_map_num;
+
+ if (req_num >= cb->max_crossbar_sources) {
+ direct_map_num = req_num - cb->max_crossbar_sources;
+ if (direct_map_num < cb->int_max) {
+ ret = cb->irq_map[direct_map_num];
+ if (ret == IRQ_RESERVED || ret == IRQ_SKIP) {
+ /* We use the interrupt num as h/w irq num */
+ ret = direct_map_num;
+ goto found;
+ }
+ }
- ret = get_prev_map_irq(intspec[1]);
- if (!IS_ERR_VALUE(ret))
+ pr_err("%s: requested crossbar number %d > max %d\n",
+ __func__, req_num, cb->max_crossbar_sources);
+ return -EINVAL;
+ }
+
+ ret = get_prev_map_irq(req_num);
+ if (ret >= 0)
goto found;
- ret = allocate_free_irq(intspec[1]);
+ ret = allocate_free_irq(req_num);
- if (IS_ERR_VALUE(ret))
+ if (ret < 0)
return ret;
found:
return 0;
}
-const struct irq_domain_ops routable_irq_domain_ops = {
+static const struct irq_domain_ops routable_irq_domain_ops = {
.map = crossbar_domain_map,
.unmap = crossbar_domain_unmap,
.xlate = crossbar_domain_xlate
static int __init crossbar_of_init(struct device_node *node)
{
- int i, size, max, reserved = 0, entry;
+ int i, size, max = 0, reserved = 0, entry;
const __be32 *irqsr;
+ int ret = -ENOMEM;
cb = kzalloc(sizeof(*cb), GFP_KERNEL);
if (!cb)
- return -ENOMEM;
+ return ret;
cb->crossbar_base = of_iomap(node, 0);
if (!cb->crossbar_base)
- goto err1;
+ goto err_cb;
+
+ of_property_read_u32(node, "ti,max-crossbar-sources",
+ &cb->max_crossbar_sources);
+ if (!cb->max_crossbar_sources) {
+ pr_err("missing 'ti,max-crossbar-sources' property\n");
+ ret = -EINVAL;
+ goto err_base;
+ }
of_property_read_u32(node, "ti,max-irqs", &max);
- cb->irq_map = kzalloc(max * sizeof(int), GFP_KERNEL);
+ if (!max) {
+ pr_err("missing 'ti,max-irqs' property\n");
+ ret = -EINVAL;
+ goto err_base;
+ }
+ cb->irq_map = kcalloc(max, sizeof(int), GFP_KERNEL);
if (!cb->irq_map)
- goto err2;
+ goto err_base;
cb->int_max = max;
i, &entry);
if (entry > max) {
pr_err("Invalid reserved entry\n");
- goto err3;
+ ret = -EINVAL;
+ goto err_irq_map;
}
cb->irq_map[entry] = IRQ_RESERVED;
}
}
- cb->register_offsets = kzalloc(max * sizeof(int), GFP_KERNEL);
+ /* Skip irqs hardwired to bypass the crossbar */
+ irqsr = of_get_property(node, "ti,irqs-skip", &size);
+ if (irqsr) {
+ size /= sizeof(__be32);
+
+ for (i = 0; i < size; i++) {
+ of_property_read_u32_index(node,
+ "ti,irqs-skip",
+ i, &entry);
+ if (entry > max) {
+ pr_err("Invalid skip entry\n");
+ ret = -EINVAL;
+ goto err_irq_map;
+ }
+ cb->irq_map[entry] = IRQ_SKIP;
+ }
+ }
+
+
+ cb->register_offsets = kcalloc(max, sizeof(int), GFP_KERNEL);
if (!cb->register_offsets)
- goto err3;
+ goto err_irq_map;
of_property_read_u32(node, "ti,reg-size", &size);
break;
default:
pr_err("Invalid reg-size property\n");
- goto err4;
+ ret = -EINVAL;
+ goto err_reg_offset;
break;
}
reserved += size;
}
+ of_property_read_u32(node, "ti,irqs-safe-map", &cb->safe_map);
+ /* Initialize the crossbar with safe map to start with */
+ for (i = 0; i < max; i++) {
+ if (cb->irq_map[i] == IRQ_RESERVED ||
+ cb->irq_map[i] == IRQ_SKIP)
+ continue;
+
+ cb->write(i, cb->safe_map);
+ }
+
register_routable_domain_ops(&routable_irq_domain_ops);
return 0;
-err4:
+err_reg_offset:
kfree(cb->register_offsets);
-err3:
+err_irq_map:
kfree(cb->irq_map);
-err2:
+err_base:
iounmap(cb->crossbar_base);
-err1:
+err_cb:
kfree(cb);
- return -ENOMEM;
+
+ cb = NULL;
+ return ret;
}
static const struct of_device_id crossbar_match[] __initconst = {
projects / karo-tx-linux.git / blobdiff