[PATCH v10 3/4] irqchip:create irq domain for each mbigen device

MaJun
2015-12-17T11:56:36Z

From: Ma Jun <majun258@huawei.com>

For peripheral devices which connect to mbigen,mbigen is a interrupt
controller. So, we create irq domain for each mbigen device and add
mbigen irq domain into irq hierarchy structure.

Signed-off-by: Ma Jun <majun258@huawei.com>
---
drivers/irqchip/irq-mbigen.c | 138 ++++++++++++++++++++++++++++++++++++++++++
1 files changed, 138 insertions(+), 0 deletions(-)

diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c
index 9f036c2..98865b1 100644
--- a/drivers/irqchip/irq-mbigen.c
+++ b/drivers/irqchip/irq-mbigen.c
@@ -16,13 +16,39 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/

+#include <linux/interrupt.h>
+#include <linux/irqchip.h>
#include <linux/module.h>
+#include <linux/msi.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

+/* Interrupt numbers per mbigen node supported */
+#define IRQS_PER_MBIGEN_NODE 128
+
+/* 64 irqs (Pin0-pin63) are reserved for each mbigen chip */
+#define RESERVED_IRQ_PER_MBIGEN_CHIP 64
+
+/* The maximum IRQ pin number of mbigen chip(start from 0) */
+#define MAXIMUM_IRQ_PIN_NUM 1407
+
+/**
+ * In mbigen vector register
+ * bit[21:12]: event id value
+ * bit[11:0]: device id
+ */
+#define IRQ_EVENT_ID_SHIFT 12
+#define IRQ_EVENT_ID_MASK 0x3ff
+
+/* register range of each mbigen node */
+#define MBIGEN_NODE_OFFSET 0x1000
+
+/* offset of vector register in mbigen node */
+#define REG_MBIGEN_VEC_OFFSET 0x200
+
/**
* struct mbigen_device - holds the information of mbigen device.
*
@@ -34,10 +60,107 @@ struct mbigen_device {
void __iomem *base;
};

+static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
+{
+ unsigned int nid, pin;
+
+ hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
+ nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
+ pin = hwirq % IRQS_PER_MBIGEN_NODE;
+
+ return pin * 4 + nid * MBIGEN_NODE_OFFSET
+ + REG_MBIGEN_VEC_OFFSET;
+}
+
+static struct irq_chip mbigen_irq_chip = {
+ .name = "mbigen-v2",
+};
+
+static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+ struct irq_data *d = irq_get_irq_data(desc->irq);
+ void __iomem *base = d->chip_data;
+ u32 val;
+
+ base += get_mbigen_vec_reg(d->hwirq);
+ val = readl_relaxed(base);
+
+ val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
+ val |= (msg->data << IRQ_EVENT_ID_SHIFT);
+
+ /* The address of doorbell is encoded in mbigen register by default
+ * So,we don't need to program the doorbell address@here
+ */
+ writel_relaxed(val, base);
+}
+
+static int mbigen_domain_translate(struct irq_domain *d,
+ struct irq_fwspec *fwspec,
+ unsigned long *hwirq,
+ unsigned int *type)
+{
+ if (is_of_node(fwspec->fwnode)) {
+ if (fwspec->param_count != 2)
+ return -EINVAL;
+
+ if ((fwspec->param[0] > MAXIMUM_IRQ_PIN_NUM) ||
+ (fwspec->param[0] < RESERVED_IRQ_PER_MBIGEN_CHIP))
+ return -EINVAL;
+ else
+ *hwirq = fwspec->param[0];
+
+ /* If there is no valid irq type, just use the default type */
+ if ((fwspec->param[1] == IRQ_TYPE_EDGE_RISING) ||
+ (fwspec->param[1] == IRQ_TYPE_LEVEL_HIGH))
+ *type = fwspec->param[1];
+ else
+ *type = IRQ_TYPE_NONE;
+
+ return 0;
+ }
+ return -EINVAL;
+}
+
+static int mbigen_irq_domain_alloc(struct irq_domain *domain,
+ unsigned int virq,
+ unsigned int nr_irqs,
+ void *args)
+{
+ struct irq_fwspec *fwspec = args;
+ irq_hw_number_t hwirq;
+ unsigned int type;
+ struct mbigen_device *mgn_chip;
+ int i, err;
+
+ err = mbigen_domain_translate(domain, fwspec, &hwirq, &type);
+ if (err)
+ return err;
+
+ err = platform_msi_domain_alloc(domain, virq, nr_irqs);
+ if (err)
+ return err;
+
+ mgn_chip = platform_msi_get_host_data(domain);
+
+ for (i = 0; i < nr_irqs; i++)
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &mbigen_irq_chip, mgn_chip->base);
+
+ return 0;
+}
+
+static struct irq_domain_ops mbigen_domain_ops = {
+ .translate = mbigen_domain_translate,
+ .alloc = mbigen_irq_domain_alloc,
+ .free = irq_domain_free_irqs_common,
+};
+
static int mbigen_device_probe(struct platform_device *pdev)
{
struct mbigen_device *mgn_chip;
struct resource *res;
+ struct irq_domain *domain;
+ u32 num_msis;

mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
if (!mgn_chip)
@@ -50,8 +173,23 @@ static int mbigen_device_probe(struct platform_device *pdev)
if (IS_ERR(mgn_chip->base))
return PTR_ERR(mgn_chip->base);

+ if (of_property_read_u32(pdev->dev.of_node, "num-msis", &num_msis) < 0) {
+ dev_err(&pdev->dev, "No num-msis property\n");
+ return -EINVAL;
+ }
+
+ domain = platform_msi_create_device_domain(&pdev->dev, num_msis,
+ mbigen_write_msg,
+ &mbigen_domain_ops,
+ mgn_chip);
+
+ if (!domain)
+ return -ENOMEM;
+
platform_set_drvdata(pdev, mgn_chip);

+ dev_info(&pdev->dev, "Probing ok, allocated %d MSIs\n", num_msis);
+
return 0;
}

--
1.7.1