Hi Sinan, On 02/05/2016 05:34 AM, Sinan Kaya wrote: > In situations where the userspace driver is stopped abnormally and the > VFIO platform device is released, the assigned HW device currently is > left running. As a consequence the HW device might continue issuing IRQs > and performing DMA accesses. > > This patch is implementing a reset driver for HIDMA platform driver. > This gets called by the VFIO platform reset interface. > > Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx> > --- > drivers/vfio/platform/reset/Kconfig | 9 ++ > drivers/vfio/platform/reset/Makefile | 2 + > .../vfio/platform/reset/vfio_platform_qcomhidma.c | 99 ++++++++++++++++++++++ > 3 files changed, 110 insertions(+) > create mode 100644 drivers/vfio/platform/reset/vfio_platform_qcomhidma.c > > diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig > index 70cccc5..d02b3b5 100644 > --- a/drivers/vfio/platform/reset/Kconfig > +++ b/drivers/vfio/platform/reset/Kconfig > @@ -13,3 +13,12 @@ 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_QCOMHIDMA_RESET > + tristate "VFIO support for Qualcomm Technologies HIDMA reset" > + depends on VFIO_PLATFORM > + help > + Enables the VFIO platform driver to handle reset for Qualcomm Technologies > + HIDMA Channel. > + > + 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..ec7748a 100644 > --- a/drivers/vfio/platform/reset/Makefile > +++ b/drivers/vfio/platform/reset/Makefile > @@ -1,7 +1,9 @@ > vfio-platform-calxedaxgmac-y := vfio_platform_calxedaxgmac.o > vfio-platform-amdxgbe-y := vfio_platform_amdxgbe.o > +vfio-platform-qcomhidma-y := vfio_platform_qcomhidma.o > > ccflags-y += -Idrivers/vfio/platform > > obj-$(CONFIG_VFIO_PLATFORM_CALXEDAXGMAC_RESET) += vfio-platform-calxedaxgmac.o > +obj-$(CONFIG_VFIO_PLATFORM_QCOMHIDMA_RESET) += vfio-platform-qcomhidma.o > obj-$(CONFIG_VFIO_PLATFORM_AMDXGBE_RESET) += vfio-platform-amdxgbe.o > diff --git a/drivers/vfio/platform/reset/vfio_platform_qcomhidma.c b/drivers/vfio/platform/reset/vfio_platform_qcomhidma.c > new file mode 100644 > index 0000000..70d7eed > --- /dev/null > +++ b/drivers/vfio/platform/reset/vfio_platform_qcomhidma.c > @@ -0,0 +1,99 @@ > +/* > + * Qualcomm Technologies HIDMA VFIO Reset Driver > + * > + * Copyright (c) 2016, The Linux Foundation. All rights reserved. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 and > + * only 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. > + */ > + > +#include <linux/module.h> > +#include <linux/kernel.h> > +#include <linux/init.h> > +#include <linux/io.h> > +#include <linux/device.h> > +#include <linux/iopoll.h> > + > +#include "vfio_platform_private.h" > + > +#define TRCA_CTRLSTS_OFFSET 0x000 > +#define EVCA_CTRLSTS_OFFSET 0x000 > + > +#define CH_CONTROL_MASK GENMASK(7, 0) nit: alignment Besides it looks ok to me Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx> If it better suits you maybe you can separate the upstream of your management/channel driver from the VFIO reset driver upstream. Best Regards Eric > +#define CH_STATE_MASK GENMASK(7, 0) > +#define CH_STATE_BIT_POS 0x8 > + > +#define HIDMA_CH_STATE(val) \ > + ((val >> CH_STATE_BIT_POS) & CH_STATE_MASK) > + > +#define EVCA_IRQ_EN_OFFSET 0x110 > + > +#define CH_RESET 9 > +#define CH_DISABLED 0 > + > +int vfio_platform_qcomhidma_reset(struct vfio_platform_device *vdev) > +{ > + struct vfio_platform_region *trreg; > + struct vfio_platform_region *evreg; > + u32 val; > + int ret; > + > + if (vdev->num_regions != 2) > + return -ENODEV; > + > + trreg = &vdev->regions[0]; > + if (!trreg->ioaddr) { > + trreg->ioaddr = > + ioremap_nocache(trreg->addr, trreg->size); > + if (!trreg->ioaddr) > + return -ENOMEM; > + } > + > + evreg = &vdev->regions[1]; > + if (!evreg->ioaddr) { > + evreg->ioaddr = > + ioremap_nocache(evreg->addr, evreg->size); > + if (!evreg->ioaddr) > + return -ENOMEM; > + } > + > + /* disable IRQ */ > + writel(0, evreg->ioaddr + EVCA_IRQ_EN_OFFSET); > + > + /* reset both transfer and event channels */ > + val = readl(trreg->ioaddr + TRCA_CTRLSTS_OFFSET); > + val &= ~(CH_CONTROL_MASK << 16); > + val |= CH_RESET << 16; > + writel(val, trreg->ioaddr + TRCA_CTRLSTS_OFFSET); > + > + ret = readl_poll_timeout(trreg->ioaddr + TRCA_CTRLSTS_OFFSET, val, > + HIDMA_CH_STATE(val) == CH_DISABLED, 1000, > + 10000); > + if (ret) > + return ret; > + > + val = readl(evreg->ioaddr + EVCA_CTRLSTS_OFFSET); > + val &= ~(CH_CONTROL_MASK << 16); > + val |= CH_RESET << 16; > + writel(val, evreg->ioaddr + EVCA_CTRLSTS_OFFSET); > + > + ret = readl_poll_timeout(evreg->ioaddr + EVCA_CTRLSTS_OFFSET, val, > + HIDMA_CH_STATE(val) == CH_DISABLED, 1000, > + 10000); > + if (ret) > + return ret; > + > + pr_info("HIDMA channel reset\n"); > + return 0; > +} > +module_vfio_reset_handler("qcom,hidma-1.0", "QCOM8061", > + vfio_platform_qcomhidma_reset); > + > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("Reset support for Qualcomm Technologies HIDMA device"); > -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html