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* [PATCH v6] arm pl011 serial: support multi-irq request
@ 2021-08-13  3:31 Bing Fan
  2021-08-13  7:19 ` Greg KH
  2021-08-13 14:37 ` Robin Murphy
  0 siblings, 2 replies; 9+ messages in thread
From: Bing Fan @ 2021-08-13  3:31 UTC (permalink / raw)
  To: gregkh; +Cc: linux-serial, linux-kernel

From: Bing Fan <tombinfan@tencent.com>

In order to make pl011 work better, multiple interrupts are
required, such as TXIM, RXIM, RTIM, error interrupt(FE/PE/BE/OE);
at the same time, pl011 to GIC does not merge the interrupt
lines(each serial-interrupt corresponding to different GIC hardware
interrupt), so need to enable and request multiple gic interrupt
numbers in the driver.

Signed-off-by: Bing Fan <tombinfan@tencent.com>
---
 drivers/tty/serial/amba-pl011.c | 39 +++++++++++++++++++++++++++++++--
 1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index e14f3378b8a0..eaac3431459c 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -1701,6 +1701,41 @@ static void pl011_write_lcr_h(struct uart_amba_port *uap, unsigned int lcr_h)
 	}
 }
 
+static void pl011_release_multi_irqs(struct uart_amba_port *uap, unsigned int max_cnt)
+{
+	struct amba_device *amba_dev = container_of(uap->port.dev, struct amba_device, dev);
+	int i;
+
+	for (i = 0; i < max_cnt; i++)
+		if (amba_dev->irq[i])
+			free_irq(amba_dev->irq[i], uap);
+}
+
+static int pl011_allocate_multi_irqs(struct uart_amba_port *uap)
+{
+	int ret = 0;
+	int i;
+	unsigned int virq;
+	struct amba_device *amba_dev = container_of(uap->port.dev, struct amba_device, dev);
+
+	pl011_write(uap->im, uap, REG_IMSC);
+
+	for (i = 0; i < AMBA_NR_IRQS; i++) {
+		virq = amba_dev->irq[i];
+		if (virq == 0)
+			break;
+
+		ret = request_irq(virq, pl011_int, IRQF_SHARED, dev_name(&amba_dev->dev), uap);
+		if (ret) {
+			dev_err(uap->port.dev, "request %u interrupt failed\n", virq);
+			pl011_release_multi_irqs(uap, i - 1);
+			break;
+		}
+	}
+
+	return ret;
+}
+
 static int pl011_allocate_irq(struct uart_amba_port *uap)
 {
 	pl011_write(uap->im, uap, REG_IMSC);
@@ -1753,7 +1788,7 @@ static int pl011_startup(struct uart_port *port)
 	if (retval)
 		goto clk_dis;
 
-	retval = pl011_allocate_irq(uap);
+	retval = pl011_allocate_multi_irqs(uap);
 	if (retval)
 		goto clk_dis;
 
@@ -1864,7 +1899,7 @@ static void pl011_shutdown(struct uart_port *port)
 
 	pl011_dma_shutdown(uap);
 
-	free_irq(uap->port.irq, uap);
+	pl011_release_multi_irqs(uap, AMBA_NR_IRQS);
 
 	pl011_disable_uart(uap);
 
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2021-08-16 10:34 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-13  3:31 [PATCH v6] arm pl011 serial: support multi-irq request Bing Fan
2021-08-13  7:19 ` Greg KH
     [not found]   ` <9c3a4336-b6c4-d96e-9a9d-8001dddcee20@gmail.com>
2021-08-13  8:17     ` Greg KH
2021-08-13 14:08       ` Robin Murphy
2021-08-13 15:04         ` Greg KH
2021-08-13 15:17           ` Robin Murphy
2021-08-13 14:37 ` Robin Murphy
     [not found]   ` <5b68f69c-f9cd-b0a4-45dd-d6db6d09fd65@gmail.com>
2021-08-16 10:19     ` Robin Murphy
2021-08-16 10:34   ` Russell King (Oracle)

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