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From: Eddie James <eajames@linux.ibm.com>
To: linux-aspeed@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
	mark.rutland@arm.com, jason@lakedaemon.net, maz@kernel.org,
	robh+dt@kernel.org, tglx@linutronix.de, joel@jms.id.au,
	andrew@aj.id.au, eajames@linux.ibm.com
Subject: [PATCH v6 08/12] soc: aspeed: xdma: Add reset ioctl
Date: Wed, 15 Jan 2020 15:29:46 -0600	[thread overview]
Message-ID: <1579123790-6894-9-git-send-email-eajames@linux.ibm.com> (raw)
In-Reply-To: <1579123790-6894-1-git-send-email-eajames@linux.ibm.com>

Users of the XDMA engine need a way to reset it if something goes wrong.
Problems on the host side, or user error, such as incorrect host
address, may result in the DMA operation never completing and no way to
determine what went wrong. Therefore, add an ioctl to reset the engine
so that users can recover in this situation.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Acked-by: Andrew Jeffery <andrew@aj.id.au>
---
 drivers/soc/aspeed/aspeed-xdma.c | 32 ++++++++++++++++++++++++++++++++
 include/uapi/linux/aspeed-xdma.h |  4 ++++
 2 files changed, 36 insertions(+)

diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
index 1b81a08..361daca 100644
--- a/drivers/soc/aspeed/aspeed-xdma.c
+++ b/drivers/soc/aspeed/aspeed-xdma.c
@@ -615,6 +615,37 @@ static __poll_t aspeed_xdma_poll(struct file *file,
 	return mask;
 }
 
+static long aspeed_xdma_ioctl(struct file *file, unsigned int cmd,
+			      unsigned long param)
+{
+	unsigned long flags;
+	struct aspeed_xdma_client *client = file->private_data;
+	struct aspeed_xdma *ctx = client->ctx;
+
+	switch (cmd) {
+	case ASPEED_XDMA_IOCTL_RESET:
+		spin_lock_irqsave(&ctx->engine_lock, flags);
+		if (ctx->in_reset) {
+			spin_unlock_irqrestore(&ctx->engine_lock, flags);
+			return 0;
+		}
+
+		ctx->in_reset = true;
+		spin_unlock_irqrestore(&ctx->engine_lock, flags);
+
+		if (READ_ONCE(ctx->current_client))
+			dev_warn(ctx->dev,
+				 "User reset with transfer in progress.\n");
+
+		aspeed_xdma_reset(ctx);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static void aspeed_xdma_vma_close(struct vm_area_struct *vma)
 {
 	int rc;
@@ -708,6 +739,7 @@ static int aspeed_xdma_release(struct inode *inode, struct file *file)
 	.owner			= THIS_MODULE,
 	.write			= aspeed_xdma_write,
 	.poll			= aspeed_xdma_poll,
+	.unlocked_ioctl		= aspeed_xdma_ioctl,
 	.mmap			= aspeed_xdma_mmap,
 	.open			= aspeed_xdma_open,
 	.release		= aspeed_xdma_release,
diff --git a/include/uapi/linux/aspeed-xdma.h b/include/uapi/linux/aspeed-xdma.h
index 2efaa60..3a3646f 100644
--- a/include/uapi/linux/aspeed-xdma.h
+++ b/include/uapi/linux/aspeed-xdma.h
@@ -4,8 +4,12 @@
 #ifndef _UAPI_LINUX_ASPEED_XDMA_H_
 #define _UAPI_LINUX_ASPEED_XDMA_H_
 
+#include <linux/ioctl.h>
 #include <linux/types.h>
 
+#define __ASPEED_XDMA_IOCTL_MAGIC	0xb7
+#define ASPEED_XDMA_IOCTL_RESET		_IO(__ASPEED_XDMA_IOCTL_MAGIC, 0)
+
 /*
  * aspeed_xdma_direction
  *
-- 
1.8.3.1


  parent reply	other threads:[~2020-01-15 21:30 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-15 21:29 [PATCH v6 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
2020-01-15 21:29 ` [PATCH v6 01/12] dt-bindings: interrupt-controller: Add Aspeed SCU interrupt controller Eddie James
2020-01-15 21:29 ` [PATCH v6 02/12] irqchip: " Eddie James
2020-01-15 21:29 ` [PATCH v6 03/12] ARM: dts: aspeed: ast2500: Add " Eddie James
2020-01-15 21:29 ` [PATCH v6 04/12] ARM: dts: aspeed: ast2600: Add SCU interrupt controllers Eddie James
2020-01-15 21:29 ` [PATCH v6 05/12] dt-bindings: soc: Add Aspeed XDMA Engine Eddie James
2020-01-17  0:01   ` Andrew Jeffery
2020-01-15 21:29 ` [PATCH v6 06/12] soc: aspeed: Add XDMA Engine Driver Eddie James
2020-01-17  0:07   ` Andrew Jeffery
2020-02-10 16:35   ` Arnd Bergmann
2020-02-10 17:10     ` Eddie James
2020-03-16  4:49       ` Joel Stanley
2020-02-16 23:56     ` Andrew Jeffery
2020-01-15 21:29 ` [PATCH v6 07/12] soc: aspeed: xdma: Add user interface Eddie James
2020-01-17  0:09   ` Andrew Jeffery
2020-01-15 21:29 ` Eddie James [this message]
2020-01-15 21:29 ` [PATCH v6 09/12] ARM: dts: aspeed: ast2500: Add XDMA Engine Eddie James
2020-01-15 21:29 ` [PATCH v6 10/12] ARM: dts: aspeed: ast2600: " Eddie James
2020-01-15 21:29 ` [PATCH v6 11/12] ARM: dts: aspeed: witherspoon: Enable " Eddie James
2020-01-17  0:12   ` Andrew Jeffery
2020-01-15 21:29 ` [PATCH v6 12/12] ARM: dts: aspeed: tacoma: Enable XDMA engine Eddie James
2020-01-17  0:13   ` Andrew Jeffery
2020-01-20  8:54 ` [PATCH v6 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Marc Zyngier

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