Commit 9a8d3cda authored by Russ Weight's avatar Russ Weight Committed by Moritz Fischer
Browse files

fpga: dfl: afu: harden port enable logic 



Port enable is not complete until ACK = 0. Change
__afu_port_enable() to guarantee that the enable process
is complete by polling for ACK == 0.

Signed-off-by: default avatarRuss Weight <russell.h.weight@intel.com>
Reviewed-by: default avatarTom Rix <trix@redhat.com>
Reviewed-by: default avatarMatthew Gerlach <matthew.gerlach@linux.intel.com>
Acked-by: default avatarWu Hao <hao.wu@intel.com>
Signed-off-by: default avatarMoritz Fischer <mdf@kernel.org>
parent 6f1e376c

drivers/fpga/dfl-afu-error.c

+6 −4
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ static int afu_port_err_clear(struct device *dev, u64 err) 
	struct dfl_feature_platform_data *pdata = dev_get_platdata(dev);

	struct platform_device *pdev = to_platform_device(dev);

	void __iomem *base_err, *base_hdr;

	int ret = -EBUSY;

	int enable_ret = 0, ret = -EBUSY;

	u64 v;



	base_err = dfl_get_feature_ioaddr_by_id(dev, PORT_FEATURE_ID_ERROR);
@@ -96,18 +96,20 @@ static int afu_port_err_clear(struct device *dev, u64 err) 
		v = readq(base_err + PORT_FIRST_ERROR);

		writeq(v, base_err + PORT_FIRST_ERROR);

	} else {

		dev_warn(dev, "%s: received 0x%llx, expected 0x%llx\n",

			 __func__, v, err);

		ret = -EINVAL;

	}



	/* Clear mask */

	__afu_port_err_mask(dev, false);



	/* Enable the Port by clear the reset */

	__afu_port_enable(pdev);

	/* Enable the Port by clearing the reset */

	enable_ret = __afu_port_enable(pdev);



done:

	mutex_unlock(&pdata->lock);

	return ret;

	return enable_ret ? enable_ret : ret;

}



static ssize_t errors_show(struct device *dev, struct device_attribute *attr,

drivers/fpga/dfl-afu-main.c

+24 −11
Original line number Diff line number Diff line
@@ -21,6 +21,9 @@ 


#include "dfl-afu.h"



#define RST_POLL_INVL 10 /* us */

#define RST_POLL_TIMEOUT 1000 /* us */



/**

 * __afu_port_enable - enable a port by clear reset

 * @pdev: port platform device.
@@ -32,7 +35,7 @@ 
 *

 * The caller needs to hold lock for protection.

 */

void __afu_port_enable(struct platform_device *pdev)

int __afu_port_enable(struct platform_device *pdev)

{

	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);

	void __iomem *base;
@@ -41,7 +44,7 @@ void __afu_port_enable(struct platform_device *pdev) 
	WARN_ON(!pdata->disable_count);



	if (--pdata->disable_count != 0)

		return;

		return 0;



	base = dfl_get_feature_ioaddr_by_id(&pdev->dev, PORT_FEATURE_ID_HEADER);
@@ -49,10 +52,20 @@ void __afu_port_enable(struct platform_device *pdev) 
	v = readq(base + PORT_HDR_CTRL);

	v &= ~PORT_CTRL_SFTRST;

	writeq(v, base + PORT_HDR_CTRL);



	/*

	 * HW clears the ack bit to indicate that the port is fully out

	 * of reset.

	 */

	if (readq_poll_timeout(base + PORT_HDR_CTRL, v,

			       !(v & PORT_CTRL_SFTRST_ACK),

			       RST_POLL_INVL, RST_POLL_TIMEOUT)) {

		dev_err(&pdev->dev, "timeout, failure to enable device\n");

		return -ETIMEDOUT;

	}



#define RST_POLL_INVL 10 /* us */

#define RST_POLL_TIMEOUT 1000 /* us */

	return 0;

}



/**

 * __afu_port_disable - disable a port by hold reset
@@ -86,7 +99,7 @@ int __afu_port_disable(struct platform_device *pdev) 
	if (readq_poll_timeout(base + PORT_HDR_CTRL, v,

			       v & PORT_CTRL_SFTRST_ACK,

			       RST_POLL_INVL, RST_POLL_TIMEOUT)) {

		dev_err(&pdev->dev, "timeout, fail to reset device\n");

		dev_err(&pdev->dev, "timeout, failure to disable device\n");

		return -ETIMEDOUT;

	}
@@ -110,10 +123,10 @@ static int __port_reset(struct platform_device *pdev) 
	int ret;



	ret = __afu_port_disable(pdev);

	if (!ret)

		__afu_port_enable(pdev);



	if (ret)

		return ret;



	return __afu_port_enable(pdev);

}



static int port_reset(struct platform_device *pdev)
@@ -872,11 +885,11 @@ static int afu_dev_destroy(struct platform_device *pdev) 
static int port_enable_set(struct platform_device *pdev, bool enable)

{

	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);

	int ret = 0;

	int ret;



	mutex_lock(&pdata->lock);

	if (enable)

		__afu_port_enable(pdev);

		ret = __afu_port_enable(pdev);

	else

		ret = __afu_port_disable(pdev);

	mutex_unlock(&pdata->lock);

drivers/fpga/dfl-afu.h

+1 −1
Original line number Diff line number Diff line
@@ -80,7 +80,7 @@ struct dfl_afu { 
};



/* hold pdata->lock when call __afu_port_enable/disable */

void __afu_port_enable(struct platform_device *pdev);

int __afu_port_enable(struct platform_device *pdev);

int __afu_port_disable(struct platform_device *pdev);



void afu_mmio_region_init(struct dfl_feature_platform_data *pdata);