This patch adds Broadcom FlexRM low-level reset for VFIO platform. It will do the following: 1. Disable/Deactivate each FlexRM ring 2. Flush each FlexRM ring The cleanup sequence for FlexRM rings is adapted from Broadcom FlexRM mailbox driver. Signed-off-by: Anup Patel <anup.patel@xxxxxxxxxxxx> Reviewed-by: Oza Oza <oza.oza@xxxxxxxxxxxx> Reviewed-by: Scott Branden <scott.branden@xxxxxxxxxxxx> Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx> --- drivers/vfio/platform/reset/Kconfig | 8 ++ drivers/vfio/platform/reset/Makefile | 1 + .../vfio/platform/reset/vfio_platform_bcmflexrm.c | 100 +++++++++++++++++++++ 3 files changed, 109 insertions(+) create mode 100644 drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig index 70cccc5..8833805 100644 --- a/drivers/vfio/platform/reset/Kconfig +++ b/drivers/vfio/platform/reset/Kconfig @@ -13,3 +13,11 @@ config VFIO_PLATFORM_AMDXGBE_RESET Enables the VFIO platform driver to handle reset for AMD XGBE If you don't know what to do here, say N. + +config VFIO_PLATFORM_BCMFLEXRM_RESET + tristate "VFIO support for Broadcom FlexRM reset" + depends on VFIO_PLATFORM && (ARCH_BCM_IPROC || COMPILE_TEST) + help + Enables the VFIO platform driver to handle reset for Broadcom FlexRM + + 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 93f4e23..8d9874b 100644 --- a/drivers/vfio/platform/reset/Makefile +++ b/drivers/vfio/platform/reset/Makefile @@ -5,3 +5,4 @@ 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 +obj-$(CONFIG_VFIO_PLATFORM_BCMFLEXRM_RESET) += vfio_platform_bcmflexrm.o diff --git a/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c new file mode 100644 index 0000000..104c3c1 --- /dev/null +++ b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c @@ -0,0 +1,100 @@ +/* + * Copyright (C) 2017 Broadcom + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that 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/>. + */ + +/* + * This driver provides reset support for Broadcom FlexRM ring manager + * to VFIO platform. + */ + +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> + +#include "vfio_platform_private.h" + +/* FlexRM configuration */ +#define RING_REGS_SIZE 0x10000 +#define RING_VER_MAGIC 0x76303031 + +/* Per-Ring register offsets */ +#define RING_VER 0x000 +#define RING_CONTROL 0x034 +#define RING_FLUSH_DONE 0x038 + +/* Register RING_CONTROL fields */ +#define CONTROL_FLUSH_SHIFT 5 + +/* Register RING_FLUSH_DONE fields */ +#define FLUSH_DONE_MASK 0x1 + +static int vfio_platform_bcmflexrm_shutdown(void __iomem *ring) +{ + unsigned int timeout; + + /* Disable/inactivate ring */ + writel_relaxed(0x0, ring + RING_CONTROL); + + /* Flush ring with timeout of 1s */ + timeout = 1000; + writel_relaxed(BIT(CONTROL_FLUSH_SHIFT), ring + RING_CONTROL); + do { + if (readl_relaxed(ring + RING_FLUSH_DONE) & FLUSH_DONE_MASK) + break; + mdelay(1); + } while (timeout--); + + if (!timeout) { + pr_warn("VFIO FlexRM shutdown timeout\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int vfio_platform_bcmflexrm_reset(struct vfio_platform_device *vdev) +{ + int rc = 0; + void __iomem *ring; + struct vfio_platform_region *reg = &vdev->regions[0]; + + /* Map FlexRM ring registers if not mapped */ + if (!reg->ioaddr) { + reg->ioaddr = ioremap_nocache(reg->addr, reg->size); + if (!reg->ioaddr) + return -ENOMEM; + } + + /* Discover and shutdown each FlexRM ring */ + for (ring = reg->ioaddr; + ring < (reg->ioaddr + reg->size); ring += RING_REGS_SIZE) { + if (readl_relaxed(ring + RING_VER) == RING_VER_MAGIC) { + rc = vfio_platform_bcmflexrm_shutdown(ring); + if (rc) + break; + } + } + + return rc; +} + +module_vfio_reset_handler("brcm,iproc-flexrm-mbox", + vfio_platform_bcmflexrm_reset); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Anup Patel <anup.patel@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Reset support for Broadcom FlexRM VFIO platform device"); -- 2.7.4
