Re: [PATCH v2 15/22] fpga: intel: add fpga manager platform driver for FME

[Wu Hao <hao.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

On Wed, Sep 27, 2017 at 01:54:58PM -0500, Alan Tull wrote:
> On Tue, Sep 26, 2017 at 8:18 PM, Wu Hao <hao.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> wrote:
> 
> Hi Hao,
> 
> > On Mon, Sep 25, 2017 at 02:24:57PM -0700, Moritz Fischer wrote:
> >> Hi Hao,
> >
> > Hi Moritz
> >
> > Thanks for your review. :)
> >
> >>
> >> On Mon, Jun 26, 2017 at 09:52:11AM +0800, Wu Hao wrote:
> >> > This patch adds fpga manager driver for Intel FPGA Management
> >> > Engine(FME). It implements fpga_manager_ops for FPGA Partial
> >> > Reconfiguration function.
> >> >
> >> > Signed-off-by: Tim Whisonant <tim.whisonant-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > Signed-off-by: Enno Luebbers <enno.luebbers-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > Signed-off-by: Shiva Rao <shiva.rao-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > Signed-off-by: Christopher Rauer <christopher.rauer-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > Signed-off-by: Kang Luwei <luwei.kang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > Signed-off-by: Xiao Guangrong <guangrong.xiao-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> >> > Signed-off-by: Wu Hao <hao.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > ---
> >> >  .../ABI/testing/sysfs-platform-intel-fpga-fme-mgr  |   8 +
> >> >  drivers/fpga/Kconfig                               |   7 +
> >> >  drivers/fpga/Makefile                              |   1 +
> >> >  drivers/fpga/intel-feature-dev.h                   |  75 +++++
> >> >  drivers/fpga/intel-fpga-fme-mgr.c                  | 307 +++++++++++++++++++++
> >> >  5 files changed, 398 insertions(+)
> >> >  create mode 100644 Documentation/ABI/testing/sysfs-platform-intel-fpga-fme-mgr
> >> >  create mode 100644 drivers/fpga/intel-fpga-fme-mgr.c
> >> >
> >> > diff --git a/Documentation/ABI/testing/sysfs-platform-intel-fpga-fme-mgr b/Documentation/ABI/testing/sysfs-platform-intel-fpga-fme-mgr
> >> > new file mode 100644
> >> > index 0000000..40771fb
> >> > --- /dev/null
> >> > +++ b/Documentation/ABI/testing/sysfs-platform-intel-fpga-fme-mgr
> >> > @@ -0,0 +1,8 @@
> >> > +What:              /sys/bus/platform/devices/intel-fpga-fme-mgr.0/interface_id
> >> > +Date:              June 2017
> >> > +KernelVersion:  4.12
> >> > +Contact:   Wu Hao <hao.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > +Description:       Read-only. It returns interface id of partial reconfiguration
> >> > +           hardware. Userspace could use this information to check if
> >> > +           current hardware is compatible with given image before FPGA
> >> > +           programming.
> >> > diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> >> > index b91458f..6f2f623 100644
> >> > --- a/drivers/fpga/Kconfig
> >> > +++ b/drivers/fpga/Kconfig
> >> > @@ -151,6 +151,13 @@ config INTEL_FPGA_FME
> >> >       all FPGA platform level management features. There shall be 1
> >> >       FME per Intel FPGA.
> >> >
> >> > +config INTEL_FPGA_FME_MGR
> >> > +   tristate "Intel FPGA FME Manager Driver"
> >> > +   depends on INTEL_FPGA_FME
> >> > +   help
> >> > +     Say Y to enable FPGA Manager driver for Intel FPGA Management
> >> > +     Engine.
> >> > +
> >> >  endif
> >> >
> >> >  endif # FPGA
> >> > diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> >> > index acda5ca..d1d588b 100644
> >> > --- a/drivers/fpga/Makefile
> >> > +++ b/drivers/fpga/Makefile
> >> > @@ -31,6 +31,7 @@ obj-$(CONFIG_OF_FPGA_REGION)              += of-fpga-region.o
> >> >  # Intel FPGA Support
> >> >  obj-$(CONFIG_INTEL_FPGA_PCI)               += intel-fpga-pci.o
> >> >  obj-$(CONFIG_INTEL_FPGA_FME)               += intel-fpga-fme.o
> >> > +obj-$(CONFIG_INTEL_FPGA_FME_MGR)   += intel-fpga-fme-mgr.o
> >> >
> >> >  intel-fpga-pci-objs := intel-pcie.o intel-feature-dev.o
> >> >  intel-fpga-fme-objs := intel-fme-main.o intel-fme-pr.o
> >> > diff --git a/drivers/fpga/intel-feature-dev.h b/drivers/fpga/intel-feature-dev.h
> >> > index 3f97b75..f33923b 100644
> >> > --- a/drivers/fpga/intel-feature-dev.h
> >> > +++ b/drivers/fpga/intel-feature-dev.h
> >> > @@ -164,8 +164,83 @@ struct feature_fme_err {
> >> >  };
> >> >
> >> >  /* FME Partial Reconfiguration Sub Feature Register Set */
> >> > +/* FME PR Control Register */
> >> > +struct feature_fme_pr_ctl {
> >> > +   union {
> >> > +           u64 csr;
> >> > +           struct {
> >> > +                   u64 pr_reset:1;         /* Reset PR Engine */
> >> > +                   u64 rsvdz1:3;
> >> > +                   u64 pr_reset_ack:1;     /* Reset PR Engine Ack */
> >> > +                   u64 rsvdz2:3;
> >> > +                   u64 pr_regionid:2;      /* PR Region ID */
> >> > +                   u64 rsvdz3:2;
> >> > +                   u64 pr_start_req:1;     /* PR Start Request */
> >> > +                   u64 pr_push_complete:1; /* PR Data push complete */
> >> > +                   u64 pr_kind:1;          /* Load Customer or Intel GBS */
> >> > +                   u64 rsvdz4:17;
> >> > +                   u64 config_data:32;
> >> > +           };
> >> > +   };
> >> > +};
> >> > +
> >> > +/* FME PR Status Register */
> >> > +struct feature_fme_pr_status {
> >> > +   union {
> >> > +           u64 csr;
> >> > +           struct {
> >> > +                   u64 pr_credit:9;        /* Number of PR Credits */
> >> > +                   u64 rsvdz1:7;
> >> > +                   u64 pr_status:1;        /* PR Operation status */
> >> > +                   u64 rsvdz2:3;
> >> > +                   u64 pr_ctrlr_status:3;  /* Controller status */
> >> > +                   u64 rsvdz3:1;
> >> > +                   u64 pr_host_status:4;   /* PR Host status */
> >> > +                   u64 rsvdz4:36;
> >> > +           };
> >> > +   };
> >> > +};
> >> > +
> >> > +/* FME PR Data Register */
> >> > +struct feature_fme_pr_data {
> >> > +   union {
> >> > +           u64 csr;
> >> > +           struct {
> >> > +                   /* PR data from the raw-binary file */
> >> > +                   u64 pr_data_raw:32;
> >> > +                   u64 rsvd:32;
> >> > +           };
> >> > +   };
> >> > +};
> >> > +
> >> > +/* FME PR Error Register */
> >> > +struct feature_fme_pr_error {
> >> > +   union {
> >> > +           u64 csr;
> >> > +           struct {
> >> > +                   u64 operation_err:1;    /* Previous PR error detected */
> >> > +                   u64 crc_err:1;          /* CRC error detected */
> >> > +                   u64 incompatiable_bs:1; /* Incompatiable Bitstream */
> >> > +                   u64 protocol_err:1;     /* Data push protocol error */
> >> > +                   u64 fifo_overflow:1;    /* Data fifo overflow */
> >> > +                   u64 rsvdz1:1;
> >> > +                   u64 secure_load_err:1;  /* Secure PR load error */
> >> > +                   u64 rsvdz2:57;
> >> > +           };
> >> > +   };
> >> > +};
> >>
> >> From what I've seen [1], [2] people weren't too happy with using bitfields,
> >> any reason we can't use explicit masking and shifts? I don't know if
> >> this is still an issue.
> >
> > I think both should work fine in our case, and compiler should give same
> > result on both. We choose bitfields as it seems to be more readable, and
> > could save some code. Do you think if we can keep it? :)
> 
> I have the same concerns as Moritz here.  I have suggested using
> regmap before back in July.  Using bitmasks and shifts would be be
> preferable.

Sure, will switch to bitmasks and shifts in the next version. : )

Thanks
Hao

> 
> Alan
> 
> >
> >>
> >> > +
> >> >  struct feature_fme_pr {
> >> >     struct feature_header header;
> >> > +   struct feature_fme_pr_ctl control;
> >> > +   struct feature_fme_pr_status status;
> >> > +   struct feature_fme_pr_data data;
> >> > +   struct feature_fme_pr_error error;
> >> > +
> >> > +   u64 rsvd[16];
> >> > +
> >> > +   u64 intfc_id_l;         /* PR interface Id Low */
> >> > +   u64 intfc_id_h;         /* PR interface Id High */
> >> >  };
> >> >
> >> >  /* PORT Header Register Set */
> >> > diff --git a/drivers/fpga/intel-fpga-fme-mgr.c b/drivers/fpga/intel-fpga-fme-mgr.c
> >> > new file mode 100644
> >> > index 0000000..5f93dfb
> >> > --- /dev/null
> >> > +++ b/drivers/fpga/intel-fpga-fme-mgr.c
> >> > @@ -0,0 +1,307 @@
> >> > +/*
> >> > + * FPGA Manager Driver for Intel FPGA Management Engine (FME)
> >> > + *
> >> > + * Copyright (C) 2017 Intel Corporation, Inc.
> >> > + *
> >> > + * Authors:
> >> > + *   Kang Luwei <luwei.kang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *   Xiao Guangrong <guangrong.xiao-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> >> > + *   Wu Hao <hao.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *   Joseph Grecco <joe.grecco-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *   Enno Luebbers <enno.luebbers-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *   Tim Whisonant <tim.whisonant-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *   Ananda Ravuri <ananda.ravuri-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *   Christopher Rauer <christopher.rauer-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *   Henry Mitchel <henry.mitchel-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> >> > + *
> >> > + * This work is licensed under the terms of the GNU GPL version 2. See
> >> > + * the COPYING file in the top-level directory.
> >> > + */
> >> > +
> >> > +#include <linux/module.h>
> >> > +#include <linux/iopoll.h>
> >> > +#include <linux/fpga/fpga-mgr.h>
> >> > +
> >> > +#include "intel-feature-dev.h"
> >> > +#include "intel-fme.h"
> >> > +
> >> > +#define PR_WAIT_TIMEOUT   8000000
> >> > +#define PR_HOST_STATUS_IDLE        0
> >> > +
> >> > +struct fme_mgr_priv {
> >> > +   void __iomem *ioaddr;
> >> > +};
> >> > +
> >> > +static ssize_t interface_id_show(struct device *dev,
> >> > +                            struct device_attribute *attr, char *buf)
> >> > +{
> >> > +   struct fpga_manager *mgr = dev_get_drvdata(dev);
> >> > +   struct fme_mgr_priv *priv = mgr->priv;
> >> > +   struct feature_fme_pr *fme_pr;
> >> > +   u64 intfc_id_l, intfc_id_h;
> >> > +
> >> > +   fme_pr = priv->ioaddr;
> >> > +
> >> > +   intfc_id_l = readq(&fme_pr->intfc_id_l);
> >> > +   intfc_id_h = readq(&fme_pr->intfc_id_h);
> >> > +
> >> > +   return scnprintf(buf, PAGE_SIZE, "%016llx%016llx\n",
> >> > +                   (unsigned long long)intfc_id_h,
> >> > +                   (unsigned long long)intfc_id_l);
> >> > +}
> >> > +static DEVICE_ATTR_RO(interface_id);
> >> > +
> >> > +static const struct attribute *fme_mgr_attrs[] = {
> >> > +   &dev_attr_interface_id.attr,
> >> > +   NULL,
> >> > +};
> >> > +
> >> > +static void fme_mgr_pr_update_status(struct fpga_manager *mgr,
> >> > +                                struct feature_fme_pr_error err)
> >> > +{
> >> > +   mgr->status = 0;
> >> > +
> >> > +   if (err.operation_err)
> >> > +           mgr->status |= FPGA_MGR_STATUS_OPERATION_ERR;
> >>
> >> Can we just have a (err & FEATURE_FME_PR_ERROR) here instead ?
> >> > +   if (err.crc_err)
> >> > +           mgr->status |= FPGA_MGR_STATUS_CRC_ERR;
> >>
> >> Can we just have a (err & FEATURE_FME_CRC_ERROR) here instead ?
> >
> > As above, do you think if we can keep the origin code here?
> > Use "if (err.crc_err)" not "if (err & FEATURE_FME_CRC_ERROR)",
> > it makes the code shorter in most cases. :)
> >
> > Thanks
> > Hao
> >
> >> > +   if (err.incompatiable_bs)
> >> > +           mgr->status |= FPGA_MGR_STATUS_INCOMPATIBLE_BS_ERR;
> >> > +   if (err.protocol_err)
> >> > +           mgr->status |= FPGA_MGR_STATUS_IP_PROTOCOL_ERR;
> >> > +   if (err.fifo_overflow)
> >> > +           mgr->status |= FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR;
> >> > +   if (err.secure_load_err)
> >> > +           mgr->status |= FPGA_MGR_STATUS_SECURE_LOAD_ERR;
> >> > +}
> >> > +
> >> > +static u64 fme_mgr_pr_err_handle(struct feature_fme_pr *fme_pr)
> >> > +{
> >> > +   struct feature_fme_pr_status fme_pr_status;
> >> > +   struct feature_fme_pr_error fme_pr_error;
> >> > +
> >> > +   fme_pr_status.csr = readq(&fme_pr->status);
> >> > +   if (!fme_pr_status.pr_status)
> >> > +           return 0;
> >> > +
> >> > +   fme_pr_error.csr = readq(&fme_pr->error);
> >> > +   writeq(fme_pr_error.csr, &fme_pr->error);
> >> > +
> >> > +   return fme_pr_error.csr;
> >> > +}
> >> > +
> >> > +static int fme_mgr_write_init(struct fpga_manager *mgr,
> >> > +                         struct fpga_image_info *info,
> >> > +                         const char *buf, size_t count)
> >> > +{
> >> > +   struct device *dev = &mgr->dev;
> >> > +   struct fme_mgr_priv *priv = mgr->priv;
> >> > +   struct feature_fme_pr *fme_pr = priv->ioaddr;
> >> > +   struct feature_fme_pr_ctl fme_pr_ctl;
> >> > +   struct feature_fme_pr_status fme_pr_status;
> >> > +   struct feature_fme_pr_error fme_pr_err;
> >> > +
> >> > +   if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
> >> > +           dev_err(dev, "only support partial reconfiguration.\n");
> >> > +           return -EINVAL;
> >> > +   }
> >> > +
> >> > +   dev_dbg(dev, "resetting PR before initiated PR\n");
> >> > +
> >> > +   fme_pr_ctl.csr = readq(&fme_pr->control);
> >> > +   fme_pr_ctl.pr_reset = 1;
> >> > +   writeq(fme_pr_ctl.csr, &fme_pr->control);
> >> > +
> >> > +   if (readq_poll_timeout(&fme_pr->control, fme_pr_ctl.csr,
> >> > +                          (fme_pr_ctl.pr_reset_ack == 1),
> >> > +                          1, PR_WAIT_TIMEOUT)) {
> >> > +           dev_err(dev, "maximum PR timeout\n");
> >> > +           return -ETIMEDOUT;
> >> > +   }
> >> > +
> >> > +   fme_pr_ctl.csr = readq(&fme_pr->control);
> >> > +   fme_pr_ctl.pr_reset = 0;
> >> > +   writeq(fme_pr_ctl.csr, &fme_pr->control);
> >> > +
> >> > +   dev_dbg(dev,
> >> > +           "waiting for PR resource in HW to be initialized and ready\n");
> >> > +
> >> > +   fme_pr_status.pr_host_status = PR_HOST_STATUS_IDLE;
> >> > +
> >> > +   if (readq_poll_timeout(&fme_pr->status, fme_pr_status.csr,
> >> > +                   (fme_pr_status.pr_host_status == PR_HOST_STATUS_IDLE),
> >> > +                   1, PR_WAIT_TIMEOUT)) {
> >> > +           dev_err(dev, "maximum PR timeout\n");
> >> > +           return -ETIMEDOUT;
> >> > +   }
> >> > +
> >> > +   dev_dbg(dev, "check and clear previous PR error\n");
> >> > +   fme_pr_err.csr = fme_mgr_pr_err_handle(fme_pr);
> >> > +   if (fme_pr_err.csr)
> >> > +           dev_dbg(dev, "previous PR error detected %llx\n",
> >> > +                        (unsigned long long)fme_pr_err.csr);
> >> > +
> >> > +   /* Clear all PR errors */
> >> > +   fme_pr_err.csr = 0;
> >> > +   fme_mgr_pr_update_status(mgr, fmCRCe_pr_err);
> >> > +
> >> > +   dev_dbg(dev, "set PR port ID\n");
> >> > +
> >> > +   fme_pr_ctl.csr = readq(&fme_pr->control);
> >> > +   fme_pr_ctl.pr_regionid = info->region_id;
> >> > +   writeq(fme_pr_ctl.csr, &fme_pr->control);
> >> > +
> >> > +   return 0;
> >> > +}
> >> > +
> >> > +static int fme_mgr_write(struct fpga_manager *mgr,
> >> > +                    const char *buf, size_t count)
> >> > +{
> >> > +   struct device *dev = &mgr->dev;
> >> > +   struct fme_mgr_priv *priv = mgr->priv;
> >> > +   struct feature_fme_pr *fme_pr = priv->ioaddr;
> >> > +   struct feature_fme_pr_ctl fme_pr_ctl;
> >> > +   struct feature_fme_pr_status fme_pr_status;
> >> > +   struct feature_fme_pr_data fme_pr_data;
> >> > +   int delay, pr_credit, i = 0;
> >> > +
> >> > +   dev_dbg(dev, "start request\n");
> >> > +
> >> > +   fme_pr_ctl.csr = readq(&fme_pr->control);
> >> > +   fme_pr_ctl.pr_start_req = 1;
> >> > +   writeq(fme_pr_ctl.csr, &fme_pr->control);
> >> > +
> >> > +   dev_dbg(dev, "pushing data from bitstream to HW\n");
> >> > +
> >> > +   fme_pr_status.csr = readq(&fme_pr->status);
> >> > +   pr_credit = fme_pr_status.pr_credit;
> >> > +
> >> > +   while (count > 0) {
> >> > +           delay = 0;
> >> > +           while (pr_credit <= 1) {
> >> > +                   if (delay++ > PR_WAIT_TIMEOUT) {
> >> > +                           dev_err(dev, "maximum try\n");
> >> > +                           return -ETIMEDOUT;
> >> > +                   }
> >> > +                   udelay(1);
> >> > +
> >> > +                   fme_pr_status.csr = readq(&fme_pr->status);
> >> > +                   pr_credit = fme_pr_status.pr_credit;
> >> > +           };
> >> > +
> >> > +           if (count >= 4) {
> >> > +                   fme_pr_data.rsvd = 0;
> >> > +                   fme_pr_data.pr_data_raw = *(((u32 *)buf) + i);
> >> > +                   writeq(fme_pr_data.csr, &fme_pr->data);
> >> > +                   count -= 4;
> >> > +                   pr_credit--;
> >> > +                   i++;
> >> > +           } else {
> >> > +                   WARN_ON(1);
> >> > +                   return -EINVAL;
> >> > +           }
> >> > +   }
> >> > +
> >> > +   return 0;
> >> > +}
> >> > +
> >> > +static int fme_mgr_write_complete(struct fpga_manager *mgr,
> >> > +                             struct fpga_image_info *info)
> >> > +{
> >> > +   struct device *dev = &mgr->dev;
> >> > +   struct fme_mgr_priv *priv = mgr->priv;
> >> > +   struct feature_fme_pr *fme_pr = priv->ioaddr;
> >> > +   struct feature_fme_pr_ctl fme_pr_ctl;
> >> > +   struct feature_fme_pr_error fme_pr_err;
> >> > +
> >> > +   fme_pr_ctl.csr = readq(&fme_pr->control);
> >> > +   fme_pr_ctl.pr_push_complete = 1;
> >> > +   writeq(fme_pr_ctl.csr, &fme_pr->control);
> >> > +
> >> > +   dev_dbg(dev, "green bitstream push complete\n");
> >> > +   dev_dbg(dev, "waiting for HW to release PR resource\n");
> >> > +
> >> > +   fme_pr_ctl.pr_start_req = 0;
> >> > +
> >> > +   if (readq_poll_timeout(&fme_pr->control, fme_pr_ctl.csr,
> >> > +                          (fme_pr_ctl.pr_start_req == 0),
> >> > +                          1, PR_WAIT_TIMEOUT)) {
> >> > +           dev_err(dev, "maximum try.\n");
> >> > +           return -ETIMEDOUT;
> >> > +   }
> >> > +
> >> > +   dev_dbg(dev, "PR operation complete, checking status\n");
> >> > +   fme_pr_err.csr = fme_mgr_pr_err_handle(fme_pr);
> >> > +   if (fme_pr_err.csr) {
> >> > +           fme_mgr_pr_update_status(mgr, fme_pr_err);
> >> > +           return -EIO;
> >> > +   }
> >> > +
> >> > +   dev_dbg(dev, "PR done successfully\n");
> >> > +   return 0;
> >> > +}
> >> > +
> >> > +static enum fpga_mgr_states fme_mgr_state(struct fpga_manager *mgr)
> >> > +{
> >> > +   return FPGA_MGR_STATE_UNKNOWN;
> >> > +}
> >> > +
> >> > +static const struct fpga_manager_ops fme_mgr_ops = {
> >> > +   .write_init = fme_mgr_write_init,
> >> > +   .write = fme_mgr_write,
> >> > +   .write_complete = fme_mgr_write_complete,
> >> > +   .state = fme_mgr_state,
> >> > +};
> >> > +
> >> > +static int fme_mgr_probe(struct platform_device *pdev)
> >> > +{
> >> > +   struct device *dev = &pdev->dev;
> >> > +   struct fme_mgr_priv *priv;
> >> > +   struct resource *res;
> >> > +   int ret;
> >> > +
> >> > +   priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> >> > +   if (!priv)
> >> > +           return -ENOMEM;
> >> > +
> >> > +   res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >> > +   priv->ioaddr = devm_ioremap(dev, res->start, resource_size(res));
> >> > +   if (IS_ERR(priv->ioaddr))
> >> > +           return PTR_ERR(priv->ioaddr);
> >> > +
> >> > +   ret = sysfs_create_files(&pdev->dev.kobj, fme_mgr_attrs);
> >> > +   if (ret)
> >> > +           return ret;
> >> > +
> >> > +   ret = fpga_mgr_register(dev, "Intel FPGA Manager", &fme_mgr_ops, priv);
> >> > +   if (ret) {
> >> > +           dev_err(dev, "unable to register FPGA manager\n");
> >> > +           sysfs_remove_files(&pdev->dev.kobj, fme_mgr_attrs);
> >> > +           return ret;
> >> > +   }
> >> > +
> >> > +   return 0;
> >> > +}
> >> > +
> >> > +static int fme_mgr_remove(struct platform_device *pdev)
> >> > +{
> >> > +   fpga_mgr_unregister(&pdev->dev);
> >> > +   sysfs_remove_files(&pdev->dev.kobj, fme_mgr_attrs);
> >> > +
> >> > +   return 0;
> >> > +}
> >> > +
> >> > +static struct platform_driver fme_mgr_driver = {
> >> > +   .driver = {
> >> > +           .name    = INTEL_FPGA_FME_MGR,
> >> > +   },
> >> > +   .probe   = fme_mgr_probe,
> >> > +   .remove  = fme_mgr_remove,
> >> > +};
> >> > +
> >> > +module_platform_driver(fme_mgr_driver);
> >> > +
> >> > +MODULE_DESCRIPTION("FPGA Manager for Intel FPGA Management Engine");
> >> > +MODULE_AUTHOR("Intel Corporation");
> >> > +MODULE_LICENSE("GPL v2");
> >> > +MODULE_ALIAS("platform:intel-fpga-fme-mgr");
> >> > --
> >> > 1.8.3.1
> >> >
> >>
> >> [1] http://yarchive.net/comp/linux/bitfields.html
> >> [2] https://lwn.net/Articles/478657/
> >>
> >> Thanks,
> >> Moritz
> >
> >