Re: [PATCH v3 14/21] fpga: dfl: add fpga manager platform driver for FME

From: Wu Hao
Date: Fri Feb 02 2018 - 04:51:57 EST

Next message: SF Markus Elfring: "Re: Adjustments for a lot of function implementations"
Previous message: Yang Shunyong: "[PATCH v3] dmaengine: dmatest: add norandom option"
In reply to: Alan Tull: "Re: [PATCH v3 14/21] fpga: dfl: add fpga manager platform driver for FME"
Next in thread: Luebbers, Enno: "Re: [PATCH v3 14/21] fpga: dfl: add fpga manager platform driver for FME"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On Thu, Feb 01, 2018 at 04:00:36PM -0600, Alan Tull wrote:
> On Mon, Nov 27, 2017 at 12:42 AM, Wu Hao <hao.wu@xxxxxxxxx> wrote:
>
> Hi Hao,
>
> A few comments below. Besides that, looks good.
>
> > This patch adds fpga manager driver for FPGA Management Engine (FME). It
> > implements fpga_manager_ops for FPGA Partial Reconfiguration function.
> >
> > Signed-off-by: Tim Whisonant <tim.whisonant@xxxxxxxxx>
> > Signed-off-by: Enno Luebbers <enno.luebbers@xxxxxxxxx>
> > Signed-off-by: Shiva Rao <shiva.rao@xxxxxxxxx>
> > Signed-off-by: Christopher Rauer <christopher.rauer@xxxxxxxxx>
> > Signed-off-by: Kang Luwei <luwei.kang@xxxxxxxxx>
> > Signed-off-by: Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
> > Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx>
> > ----
> > v3: rename driver to dfl-fpga-fme-mgr
> > implemented status callback for fpga manager
> > rebased due to fpga api changes
> > ---
> > .../ABI/testing/sysfs-platform-fpga-dfl-fme-mgr | 8 +
> > drivers/fpga/Kconfig | 6 +
> > drivers/fpga/Makefile | 1 +
> > drivers/fpga/fpga-dfl-fme-mgr.c | 318 +++++++++++++++++++++
> > drivers/fpga/fpga-dfl.h | 39 ++-
> > 5 files changed, 371 insertions(+), 1 deletion(-)
> > create mode 100644 Documentation/ABI/testing/sysfs-platform-fpga-dfl-fme-mgr
> > create mode 100644 drivers/fpga/fpga-dfl-fme-mgr.c
> >
> > diff --git a/Documentation/ABI/testing/sysfs-platform-fpga-dfl-fme-mgr b/Documentation/ABI/testing/sysfs-platform-fpga-dfl-fme-mgr
> > new file mode 100644
> > index 0000000..2d4f917
> > --- /dev/null
> > +++ b/Documentation/ABI/testing/sysfs-platform-fpga-dfl-fme-mgr
> > @@ -0,0 +1,8 @@
> > +What: /sys/bus/platform/devices/fpga-dfl-fme-mgr.0/interface_id
> > +Date: November 2017
> > +KernelVersion: 4.15
> > +Contact: Wu Hao <hao.wu@xxxxxxxxx>
> > +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.
>
> I'm a little confused by this. I can understand that the PR bitstream
> has a dependency on the FPGA's static image, but I don't understand
> the dependency of the bistream on the hardware that is used to program
> the bitstream to the FPGA.

Sorry for the confusion, the interface_id is used to indicate the version of
the hardware for partial reconfiguration (it's part of the static image of
the FPGA device). Will improve the description on this.

>
> > diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> > index 57da904..0171ecb 100644
> > --- a/drivers/fpga/Kconfig
> > +++ b/drivers/fpga/Kconfig
> > @@ -150,6 +150,12 @@ config FPGA_DFL_FME
> > FPGA platform level management features. There shall be 1 FME
> > per DFL based FPGA device.
> >
> > +config FPGA_DFL_FME_MGR
> > + tristate "FPGA DFL FME Manager Driver"
> > + depends on FPGA_DFL_FME
> > + help
> > + Say Y to enable FPGA Manager driver for FPGA Management Engine.
> > +
> > config INTEL_FPGA_DFL_PCI
> > tristate "Intel FPGA DFL PCIe Device Driver"
> > depends on PCI && FPGA_DFL
> > diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> > index cc75bb3..6378580 100644
> > --- a/drivers/fpga/Makefile
> > +++ b/drivers/fpga/Makefile
> > @@ -31,6 +31,7 @@ obj-$(CONFIG_OF_FPGA_REGION) += of-fpga-region.o
> > # FPGA Device Feature List Support
> > obj-$(CONFIG_FPGA_DFL) += fpga-dfl.o
> > obj-$(CONFIG_FPGA_DFL_FME) += fpga-dfl-fme.o
> > +obj-$(CONFIG_FPGA_DFL_FME_MGR) += fpga-dfl-fme-mgr.o
> >
> > fpga-dfl-fme-objs := dfl-fme-main.o dfl-fme-pr.o
> >
> > diff --git a/drivers/fpga/fpga-dfl-fme-mgr.c b/drivers/fpga/fpga-dfl-fme-mgr.c
> > new file mode 100644
> > index 0000000..70356ce
> > --- /dev/null
> > +++ b/drivers/fpga/fpga-dfl-fme-mgr.c
> > @@ -0,0 +1,318 @@
> > +/*
> > + * FPGA Manager Driver for FPGA Management Engine (FME)
> > + *
> > + * Copyright (C) 2017 Intel Corporation, Inc.
> > + *
> > + * Authors:
> > + * Kang Luwei <luwei.kang@xxxxxxxxx>
> > + * Xiao Guangrong <guangrong.xiao@xxxxxxxxxxxxxxx>
> > + * Wu Hao <hao.wu@xxxxxxxxx>
> > + * Joseph Grecco <joe.grecco@xxxxxxxxx>
> > + * Enno Luebbers <enno.luebbers@xxxxxxxxx>
> > + * Tim Whisonant <tim.whisonant@xxxxxxxxx>
> > + * Ananda Ravuri <ananda.ravuri@xxxxxxxxx>
> > + * Christopher Rauer <christopher.rauer@xxxxxxxxx>
> > + * Henry Mitchel <henry.mitchel@xxxxxxxxx>
> > + *
> > + * This work is licensed under the terms of the GNU GPL version 2.
> > + * SPDX-License-Identifier: GPL-2.0
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/fpga/fpga-mgr.h>
> > +
> > +#include "fpga-dfl.h"
> > +#include "dfl-fme.h"
> > +
> > +#define PR_WAIT_TIMEOUT 8000000
> > +#define PR_HOST_STATUS_IDLE 0
> > +
> > +struct fme_mgr_priv {
> > + void __iomem *ioaddr;
> > + u64 pr_error;
> > +};
> > +
> > +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;
> > + u64 intfc_id_l, intfc_id_h;
> > +
> > + intfc_id_l = readq(priv->ioaddr + FME_PR_INTFC_ID_L);
> > + intfc_id_h = readq(priv->ioaddr + 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 u64 pr_error_to_mgr_status(u64 err)
> > +{
> > + u64 status = 0;
> > +
> > + if (err & FME_PR_ERR_OPERATION_ERR)
> > + status |= FPGA_MGR_STATUS_OPERATION_ERR;
> > + if (err & FME_PR_ERR_CRC_ERR)
> > + status |= FPGA_MGR_STATUS_CRC_ERR;
> > + if (err & FME_PR_ERR_INCOMPATIBLE_BS)
> > + status |= FPGA_MGR_STATUS_INCOMPATIBLE_IMAGE_ERR;
> > + if (err & FME_PR_ERR_PROTOCOL_ERR)
> > + status |= FPGA_MGR_STATUS_IP_PROTOCOL_ERR;
> > + if (err & FME_PR_ERR_FIFO_OVERFLOW)
> > + status |= FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR;
> > +
> > + return status;
> > +}
> > +
> > +static u64 fme_mgr_pr_error_handle(void __iomem *fme_pr)
> > +{
> > + u64 pr_status, pr_error;
> > +
> > + pr_status = readq(fme_pr + FME_PR_STS);
> > + if (!(pr_status & FME_PR_STS_PR_STS))
> > + return 0;
> > +
> > + pr_error = readq(fme_pr + FME_PR_ERR);
> > + writeq(pr_error, fme_pr + FME_PR_ERR);
> > +
> > + return pr_error;
> > +}
> > +
> > +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;
> > + void __iomem *fme_pr = priv->ioaddr;
> > + u64 pr_ctrl, pr_status;
> > +
> > + if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
> > + dev_err(dev, "only support partial reconfiguration.\n");
>
> supports
>
> > + return -EINVAL;
> > + }
> > +
> > + dev_dbg(dev, "resetting PR before initiated PR\n");
> > +
> > + pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> > + pr_ctrl |= FME_PR_CTRL_PR_RST;
> > + writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> > +
> > + if (readq_poll_timeout(fme_pr + FME_PR_CTRL, pr_ctrl,
> > + pr_ctrl & FME_PR_CTRL_PR_RSTACK, 1,
> > + PR_WAIT_TIMEOUT)) {
> > + dev_err(dev, "maximum PR timeout\n");
>
> We have two dev_err's with the same "maximum PR timeout" so the user
> would not be able to see at which point the timeout occurred.
>
> I suggest to get rid of the word 'maximum' for both. This one could
> be 'reset ack timeout" or something similar.

Sure, will switch to a more specific message per your suggestion. Thanks.

>
> > + return -ETIMEDOUT;
> > + }
> > +
> > + pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> > + pr_ctrl &= ~FME_PR_CTRL_PR_RST;
> > + writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> > +
> > + dev_dbg(dev,
> > + "waiting for PR resource in HW to be initialized and ready\n");
> > +
> > + if (readq_poll_timeout(fme_pr + FME_PR_STS, pr_status,
> > + (pr_status & FME_PR_STS_PR_STS) ==
> > + FME_PR_STS_PR_STS_IDLE, 1, PR_WAIT_TIMEOUT)) {
> > + dev_err(dev, "maximum PR timeout\n");
>
> "PR_STS timeout"? Or something better.
>
> > + priv->pr_error = fme_mgr_pr_error_handle(fme_pr);
> > + return -ETIMEDOUT;
> > + }
> > +
> > + dev_dbg(dev, "check and clear previous PR error\n");
> > + priv->pr_error = fme_mgr_pr_error_handle(fme_pr);
> > + if (priv->pr_error)
> > + dev_dbg(dev, "previous PR error detected %llx\n",
> > + (unsigned long long)priv->pr_error);
> > +
> > + dev_dbg(dev, "set PR port ID\n");
> > +
> > + pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> > + pr_ctrl &= ~FME_PR_CTRL_PR_RGN_ID;
> > + pr_ctrl |= FIELD_PREP(FME_PR_CTRL_PR_RGN_ID, info->region_id);
> > + writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> > +
> > + 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;
> > + void __iomem *fme_pr = priv->ioaddr;
> > + u64 pr_ctrl, pr_status, pr_data;
> > + int delay = 0, pr_credit, i = 0;
> > +
> > + dev_dbg(dev, "start request\n");
> > +
> > + pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> > + pr_ctrl |= FME_PR_CTRL_PR_START;
> > + writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> > +
> > + dev_dbg(dev, "pushing data from bitstream to HW\n");
> > +
> > + pr_status = readq(fme_pr + FME_PR_STS);
> > + pr_credit = FIELD_GET(FME_PR_STS_PR_CREDIT, pr_status);
> > +
> > + while (count > 0) {
> > + while (pr_credit <= 1) {
> > + if (delay++ > PR_WAIT_TIMEOUT) {
> > + dev_err(dev, "maximum try\n");
>
> It looks like this is waiting for an entry in a queue and timing out
> here. Could you add a some comments for pr_credit above and this
> loop? Also a better error message, perhaps "PR credit timeout"?

Driver needs to read the PR credit to know if it could push PR data
to hardware or not. I will add more description here on this PR credit,
and use "PR credit timeout" as error message.

>
> > + return -ETIMEDOUT;
> > + }
> > + udelay(1);
> > +
> > + pr_status = readq(fme_pr + FME_PR_STS);
> > + pr_credit = FIELD_GET(FME_PR_STS_PR_CREDIT, pr_status);
> > + }
> > +
> > + if (count >= 4) {
> > + pr_data = 0;
> > + pr_data |= FIELD_PREP(FME_PR_DATA_PR_DATA_RAW,
> > + *(((u32 *)buf) + i));
> > + writeq(pr_data, fme_pr + 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;
> > + void __iomem *fme_pr = priv->ioaddr;
> > + u64 pr_ctrl;
> > +
> > + pr_ctrl = readq(fme_pr + FME_PR_CTRL);
> > + pr_ctrl |= FME_PR_CTRL_PR_COMPLETE;
> > + writeq(pr_ctrl, fme_pr + FME_PR_CTRL);
> > +
> > + dev_dbg(dev, "green bitstream push complete\n");
> > + dev_dbg(dev, "waiting for HW to release PR resource\n");
> > +
> > + if (readq_poll_timeout(fme_pr + FME_PR_CTRL, pr_ctrl,
> > + !(pr_ctrl & FME_PR_CTRL_PR_START), 1,
> > + PR_WAIT_TIMEOUT)) {
> > + dev_err(dev, "maximum try.\n");
>
> Some message specific to here also, please.
>
> > + return -ETIMEDOUT;
> > + }
> > +
> > + dev_dbg(dev, "PR operation complete, checking status\n");
> > + priv->pr_error = fme_mgr_pr_error_handle(fme_pr);
> > + if (priv->pr_error) {
> > + dev_dbg(dev, "PR error detected %llx\n",
> > + (unsigned long long)priv->pr_error);
> > + 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 u64 fme_mgr_status(struct fpga_manager *mgr)
> > +{
> > + struct fme_mgr_priv *priv = mgr->priv;
> > +
> > + return pr_error_to_mgr_status(priv->pr_error);
> > +}
> > +
> > +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,
> > + .status = fme_mgr_status,
> > +};
> > +
> > +static int fme_mgr_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct fme_mgr_priv *priv;
> > + struct fpga_manager *mgr;
> > + 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;
> > +
> > + mgr = devm_kzalloc(dev, sizeof(*mgr), GFP_KERNEL);
> > + if (!mgr)
> > + goto sysfs_remove_exit;
> > +
> > + mgr->name = "DFL FPGA Manager";
> > + mgr->mops = &fme_mgr_ops;
> > + mgr->priv = priv;
> > + mgr->parent = dev;
> > + platform_set_drvdata(pdev, mgr);
> > +
> > + ret = fpga_mgr_register(mgr);
> > + if (ret) {
> > + dev_err(dev, "unable to register FPGA manager\n");
> > + goto sysfs_remove_exit;
> > + }
> > +
> > + return 0;
> > +
> > +sysfs_remove_exit:
> > + sysfs_remove_files(&pdev->dev.kobj, fme_mgr_attrs);
> > + return ret;
> > +}
> > +
> > +static int fme_mgr_remove(struct platform_device *pdev)
> > +{
> > + struct fpga_manager *mgr = platform_get_drvdata(pdev);
> > +
> > + fpga_mgr_unregister(mgr);
> > + sysfs_remove_files(&pdev->dev.kobj, fme_mgr_attrs);
> > +
> > + return 0;
> > +}
> > +
> > +static struct platform_driver fme_mgr_driver = {
> > + .driver = {
> > + .name = FPGA_DFL_FME_MGR,
> > + },
> > + .probe = fme_mgr_probe,
> > + .remove = fme_mgr_remove,
> > +};
> > +
> > +module_platform_driver(fme_mgr_driver);
> > +
> > +MODULE_DESCRIPTION("FPGA Manager for FPGA Management Engine");
> > +MODULE_AUTHOR("Intel Corporation");
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_ALIAS("platform:fpga-dfl-fme-mgr");
> > diff --git a/drivers/fpga/fpga-dfl.h b/drivers/fpga/fpga-dfl.h
> > index e5a1094..d45eb82 100644
> > --- a/drivers/fpga/fpga-dfl.h
> > +++ b/drivers/fpga/fpga-dfl.h
> > @@ -130,7 +130,44 @@
> >
> > /* FME Partial Reconfiguration Sub Feature Register Set */
> > #define FME_PR_DFH DFH
> > -#define FME_PR_SIZE DFH_SIZE
> > +#define FME_PR_CTRL 0x8
> > +#define FME_PR_STS 0x10
> > +#define FME_PR_DATA 0x18
> > +#define FME_PR_ERR 0x20
> > +#define FME_PR_INTFC_ID_H 0xA8
> > +#define FME_PR_INTFC_ID_L 0xB0
> > +#define FME_PR_SIZE 0xB8
> > +
> > +/* FME PR Control Register Bitfield */
> > +#define FME_PR_CTRL_PR_RST BIT(0) /* Reset PR engine */
> > +#define FME_PR_CTRL_PR_RSTACK BIT(4) /* Ack for PR engine reset */
> > +#define FME_PR_CTRL_PR_RGN_ID GENMASK_ULL(9, 7) /* PR Region ID */
> > +#define FME_PR_CTRL_PR_START BIT(12) /* Start to request for PR service */
> > +#define FME_PR_CTRL_PR_COMPLETE BIT(13) /* PR data push complete notification */
> > +
> > +/* FME PR Status Register Bitfield */
> > +/* Number of available entries in HW queue inside the PR engine. */
> > +#define FME_PR_STS_PR_CREDIT GENMASK_ULL(8, 0)
> > +#define FME_PR_STS_PR_STS BIT(16) /* PR operation status */
> > +#define FME_PR_STS_PR_STS_IDLE 0
> > +#define FME_PR_STS_PR_CTRLR_STS GENMASK_ULL(22, 20) /* Controller status */
> > +#define FME_PR_STS_PR_HOST_STS GENMASK_ULL(27, 24) /* PR host status */
> > +
> > +/* FME PR Data Register Bitfield */
> > +/* PR data from the raw-binary file. */
> > +#define FME_PR_DATA_PR_DATA_RAW GENMASK_ULL(32, 0)
> > +
> > +/* FME PR Error Register */
> > +/* Previous PR Operation errors detected. */
> > +#define FME_PR_ERR_OPERATION_ERR BIT(0)
> > +/* CRC error detected. */
> > +#define FME_PR_ERR_CRC_ERR BIT(1)
> > +/* Incompatible PR bitstream detected. */
> > +#define FME_PR_ERR_INCOMPATIBLE_BS BIT(2)
> > +/* PR data push protocol violated. */
> > +#define FME_PR_ERR_PROTOCOL_ERR BIT(3)
> > +/* PR data fifo overflow error detected */
> > +#define FME_PR_ERR_FIFO_OVERFLOW BIT(4)
> >
> > /* FME HSSI Sub Feature Register Set */
> > #define FME_HSSI_DFH DFH
>
> I see fpga-dfl.h as enumeration code which is separate from any driver
> implementation specifics other than what's required for the DFL
> enumeration scheme. These PR engine #defines should move to a .h
> that is dedicated to this specific PR hardware device. If someone else
> adds a different PR device to the framework, their PR driver would
> also have its own .h. Same for any other modules that aren't central
> to DFL enumeration.

Sure, will move PR related register to a separated header file.
DFL enumeration related registers, will still be kept in fpga-dfl.h.

Thanks
Hao

>
> Thanks,
> Alan
>
> > --
> > 1.8.3.1
> >

Next message: SF Markus Elfring: "Re: Adjustments for a lot of function implementations"
Previous message: Yang Shunyong: "[PATCH v3] dmaengine: dmatest: add norandom option"
In reply to: Alan Tull: "Re: [PATCH v3 14/21] fpga: dfl: add fpga manager platform driver for FME"
Next in thread: Luebbers, Enno: "Re: [PATCH v3 14/21] fpga: dfl: add fpga manager platform driver for FME"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]