[PATCH v5 1/2] mfd: loongson-se: Add multi-node support

[Qunqin Zhao]

On the Loongson platform, each node is equipped with a security engine
device. However, due to a hardware flaw, only the device on node 0 can
trigger interrupts. Therefore, interrupts from other nodes are forwarded
by node 0. We need to check in the interrupt handler of node 0 whether
this interrupt is intended for other nodes, this can be accomplished via
shared interrupt handling.

Signed-off-by: Qunqin Zhao <zhaoqunqin@xxxxxxxxxxx>
---
 drivers/mfd/loongson-se.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/mfd/loongson-se.c b/drivers/mfd/loongson-se.c
index 3902ba377d..7f552a8ee6 100644
--- a/drivers/mfd/loongson-se.c
+++ b/drivers/mfd/loongson-se.c
@@ -140,6 +140,11 @@ static irqreturn_t se_irq_handler(int irq, void *dev_id)
 
 	int_status = readl(se->base + SE_S2LINT_STAT);
 
+	if (int_status == 0) {
+		spin_unlock(&se->dev_lock);
+		return IRQ_NONE;
+	}
+
 	/* For controller */
 	if (int_status & SE_INT_CONTROLLER) {
 		complete(&se->cmd_completion);
@@ -211,24 +216,26 @@ static int loongson_se_probe(struct platform_device *pdev)
 	if (IS_ERR(se->base))
 		return PTR_ERR(se->base);
 
-	writel(SE_INT_ALL, se->base + SE_S2LINT_EN);
-
 	nr_irq = platform_irq_count(pdev);
 	if (nr_irq <= 0)
 		return -ENODEV;
 
+	writel(SE_INT_ALL, se->base + SE_S2LINT_CL);
+
 	for (i = 0; i < nr_irq; i++) {
 		irq = platform_get_irq(pdev, i);
-		err = devm_request_irq(dev, irq, se_irq_handler, 0, "loongson-se", se);
+		err = devm_request_irq(dev, irq, se_irq_handler, IRQF_SHARED, "loongson-se", se);
 		if (err)
 			dev_err(dev, "failed to request IRQ: %d\n", irq);
 	}
 
+	writel(SE_INT_ALL, se->base + SE_S2LINT_EN);
+
 	err = loongson_se_init(se, paddr, se->dmam_size);
 	if (err)
 		return err;
 
-	return devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, engines,
+	return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, engines,
 				    ARRAY_SIZE(engines), NULL, 0, NULL);
 }
 
-- 
2.47.3