[PATCH v2 4/5] irqchip:create irq domain for each mbigen device

? 2016/2/16 16:50, Marc Zyngier ??:

On Tue, 16 Feb 2016 14:37:27 +0800
MaJun [off-list ref] wrote:

quoted

From: Ma Jun <redacted>

[...]

quoted

+	unsigned int nid;
+
+	nid = get_mbigen_nid(hwirq);
+
+	if (nid < 4)
+		return (nid * 4) + REG_MBIGEN_VEC_OFFSET;
+	else
+		return (nid - 4) * 4 + REG_MBIGEN_EXT_VEC_OFFSET;
+}
+
+static struct irq_chip mbigen_irq_chip = {
+	.name =			"mbigen-v1",
+};
+
+static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+	/* The address of doorbell is encoded in mbigen register by default
+	 * So,we don't need to program the doorbell address at here
+	 * Besides, the event ID is decided by the hardware pin number,
+	 * we can't change it in software.So, we don't need to encode the
+	 * event ID in mbigen register.
+	 */

Really? What if tomorrow I decide to change the EventID allocation
policy in the ITS driver? Have your HW engineers really baked the
behaviour of the Linux driver into the device?

Yes.
If we really need to support this chip,is there
any possible solution for this problem?

Thanks!
MaJun

I'm puzzled.

	M.