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: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Eric Auger 2015-11-03 18:20:57 +00:00 committed by Alex Williamson
parent daac3bbedb
commit 0990822c98
3 changed files with 137 additions and 0 deletions

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@ -5,3 +5,11 @@ config VFIO_PLATFORM_CALXEDAXGMAC_RESET
Enables the VFIO platform driver to handle reset for Calxeda xgmac
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.

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@ -1,5 +1,7 @@
vfio-platform-calxedaxgmac-y := vfio_platform_calxedaxgmac.o
vfio-platform-amdxgbe-y := vfio_platform_amdxgbe.o
ccflags-y += -Idrivers/vfio/platform
obj-$(CONFIG_VFIO_PLATFORM_CALXEDAXGMAC_RESET) += vfio-platform-calxedaxgmac.o
obj-$(CONFIG_VFIO_PLATFORM_AMDXGBE_RESET) += vfio-platform-amdxgbe.o

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@ -0,0 +1,127 @@
/*
* 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");