[PATCH v4] VFIO: platform: reset: AMD xgbe reset module
Eric Auger
eric.auger at linaro.org
Wed Oct 28 06:06:35 PDT 2015
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 at linaro.org>
Reviewed-by: Arnd Bergmann <arnd at arndb.de>
---
Applies on top of [PATCH v5 0/7] VFIO platform reset module rework
v3 -> v4:
- add Arnd's R-b
v2 -> v3:
- in Kconfig, add empty line between the 2 options
- remove DRIVER_VERSION, DRIVER_AUTHOR and DRIVER_DESC and put
strings directly in MODULE macros
v1 -> v2:
- uses module_vfio_reset_handler macro
---
drivers/vfio/platform/reset/Kconfig | 8 ++
drivers/vfio/platform/reset/Makefile | 2 +
.../vfio/platform/reset/vfio_platform_amdxgbe.c | 127 +++++++++++++++++++++
3 files changed, 137 insertions(+)
create mode 100644 drivers/vfio/platform/reset/vfio_platform_amdxgbe.c
diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig
index 746b96b..70cccc5 100644
--- a/drivers/vfio/platform/reset/Kconfig
+++ b/drivers/vfio/platform/reset/Kconfig
@@ -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.
diff --git a/drivers/vfio/platform/reset/Makefile b/drivers/vfio/platform/reset/Makefile
index 2a486af..93f4e23 100644
--- a/drivers/vfio/platform/reset/Makefile
+++ b/drivers/vfio/platform/reset/Makefile
@@ -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
diff --git a/drivers/vfio/platform/reset/vfio_platform_amdxgbe.c b/drivers/vfio/platform/reset/vfio_platform_amdxgbe.c
new file mode 100644
index 0000000..1636e22
--- /dev/null
+++ b/drivers/vfio/platform/reset/vfio_platform_amdxgbe.c
@@ -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 at linaro.org>");
+MODULE_DESCRIPTION("Reset support for AMD xgbe vfio platform device");
--
1.9.1
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