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Commit 0990822c authored by Eric Auger's avatar Eric Auger Committed by Alex Williamson
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VFIO: platform: reset: AMD xgbe reset module 



This patch introduces a module that registers and implements a low-level
reset function for the AMD XGBE device.

it performs the following actions:
- reset the PHY
- disable auto-negotiation
- disable & clear auto-negotiation IRQ
- soft-reset the MAC

Those tiny pieces of code are inherited from the native xgbe driver.

Signed-off-by: default avatarEric Auger <eric.auger@linaro.org>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent daac3bbe

drivers/vfio/platform/reset/Kconfig

+8 −0
Original line number Original line Diff line number Diff line
@@ -5,3 +5,11 @@ config VFIO_PLATFORM_CALXEDAXGMAC_RESET 
	  Enables the VFIO platform driver to handle reset for Calxeda xgmac

	  Enables the VFIO platform driver to handle reset for Calxeda xgmac





	  If you don't know what to do here, say N.

	  If you don't know what to do here, say N.



config VFIO_PLATFORM_AMDXGBE_RESET

	tristate "VFIO support for AMD XGBE reset"

	depends on VFIO_PLATFORM

	help

	  Enables the VFIO platform driver to handle reset for AMD XGBE



	  If you don't know what to do here, say N.

drivers/vfio/platform/reset/Makefile

+2 −0
Original line number Original line Diff line number Diff line 
vfio-platform-calxedaxgmac-y := vfio_platform_calxedaxgmac.o

vfio-platform-calxedaxgmac-y := vfio_platform_calxedaxgmac.o

vfio-platform-amdxgbe-y := vfio_platform_amdxgbe.o





ccflags-y += -Idrivers/vfio/platform

ccflags-y += -Idrivers/vfio/platform





obj-$(CONFIG_VFIO_PLATFORM_CALXEDAXGMAC_RESET) += vfio-platform-calxedaxgmac.o

obj-$(CONFIG_VFIO_PLATFORM_CALXEDAXGMAC_RESET) += vfio-platform-calxedaxgmac.o

obj-$(CONFIG_VFIO_PLATFORM_AMDXGBE_RESET) += vfio-platform-amdxgbe.o

drivers/vfio/platform/reset/vfio_platform_amdxgbe.c

0 → 100644
+127 −0
Original line number Original line Diff line number Diff line 
/*

 * VFIO platform driver specialized for AMD xgbe reset

 * reset code is inherited from AMD xgbe native driver

 *

 * Copyright (c) 2015 Linaro Ltd.

 *              www.linaro.org

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms and conditions of the GNU General Public License,

 * version 2, as published by the Free Software Foundation.

 *

 * This program is distributed in the hope it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for

 * more details.

 *

 * You should have received a copy of the GNU General Public License along with

 * this program.  If not, see <http://www.gnu.org/licenses/>.

 */



#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/io.h>

#include <uapi/linux/mdio.h>

#include <linux/delay.h>



#include "vfio_platform_private.h"



#define DMA_MR			0x3000

#define MAC_VR			0x0110

#define DMA_ISR			0x3008

#define MAC_ISR			0x00b0

#define PCS_MMD_SELECT		0xff

#define MDIO_AN_INT		0x8002

#define MDIO_AN_INTMASK		0x8001



static unsigned int xmdio_read(void *ioaddr, unsigned int mmd,

			       unsigned int reg)

{

	unsigned int mmd_address, value;



	mmd_address = (mmd << 16) | ((reg) & 0xffff);

	iowrite32(mmd_address >> 8, ioaddr + (PCS_MMD_SELECT << 2));

	value = ioread32(ioaddr + ((mmd_address & 0xff) << 2));

	return value;

}



static void xmdio_write(void *ioaddr, unsigned int mmd,

			unsigned int reg, unsigned int value)

{

	unsigned int mmd_address;



	mmd_address = (mmd << 16) | ((reg) & 0xffff);

	iowrite32(mmd_address >> 8, ioaddr + (PCS_MMD_SELECT << 2));

	iowrite32(value, ioaddr + ((mmd_address & 0xff) << 2));

}



int vfio_platform_amdxgbe_reset(struct vfio_platform_device *vdev)

{

	struct vfio_platform_region *xgmac_regs = &vdev->regions[0];

	struct vfio_platform_region *xpcs_regs = &vdev->regions[1];

	u32 dma_mr_value, pcs_value, value;

	unsigned int count;



	if (!xgmac_regs->ioaddr) {

		xgmac_regs->ioaddr =

			ioremap_nocache(xgmac_regs->addr, xgmac_regs->size);

		if (!xgmac_regs->ioaddr)

			return -ENOMEM;

	}

	if (!xpcs_regs->ioaddr) {

		xpcs_regs->ioaddr =

			ioremap_nocache(xpcs_regs->addr, xpcs_regs->size);

		if (!xpcs_regs->ioaddr)

			return -ENOMEM;

	}



	/* reset the PHY through MDIO*/

	pcs_value = xmdio_read(xpcs_regs->ioaddr, MDIO_MMD_PCS, MDIO_CTRL1);

	pcs_value |= MDIO_CTRL1_RESET;

	xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_PCS, MDIO_CTRL1, pcs_value);



	count = 50;

	do {

		msleep(20);

		pcs_value = xmdio_read(xpcs_regs->ioaddr, MDIO_MMD_PCS,

					MDIO_CTRL1);

	} while ((pcs_value & MDIO_CTRL1_RESET) && --count);



	if (pcs_value & MDIO_CTRL1_RESET)

		pr_warn("%s XGBE PHY reset timeout\n", __func__);



	/* disable auto-negotiation */

	value = xmdio_read(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_CTRL1);

	value &= ~MDIO_AN_CTRL1_ENABLE;

	xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_CTRL1, value);



	/* disable AN IRQ */

	xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_AN_INTMASK, 0);



	/* clear AN IRQ */

	xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_AN_INT, 0);



	/* MAC software reset */

	dma_mr_value = ioread32(xgmac_regs->ioaddr + DMA_MR);

	dma_mr_value |= 0x1;

	iowrite32(dma_mr_value, xgmac_regs->ioaddr + DMA_MR);



	usleep_range(10, 15);



	count = 2000;

	while (count-- && (ioread32(xgmac_regs->ioaddr + DMA_MR) & 1))

		usleep_range(500, 600);



	if (!count)

		pr_warn("%s MAC SW reset failed\n", __func__);



	return 0;

}



module_vfio_reset_handler("amd,xgbe-seattle-v1a", vfio_platform_amdxgbe_reset);



MODULE_VERSION("0.1");

MODULE_LICENSE("GPL v2");

MODULE_AUTHOR("Eric Auger <eric.auger@linaro.org>");

MODULE_DESCRIPTION("Reset support for AMD xgbe vfio platform device");