On Sun, Jun 25, 2017 at 8:52 PM, Wu Hao [off-list ref] wrote:

quoted

From: Xiao Guangrong <redacted>

Device Feature List structure creates a link list of feature headers
within the MMIO space to provide an extensible way of adding features.

The Intel FPGA PCIe driver walks through the feature headers to enumerate
feature devices, FPGA Management Engine (FME) and FPGA Port for

Accelerated

quoted

Function Unit (AFU), and their private sub features. For feature devices,
it creates the platform devices and linked the private sub features into
their platform data.

Signed-off-by: Tim Whisonant <redacted>
Signed-off-by: Enno Luebbers <redacted>
Signed-off-by: Shiva Rao <redacted>
Signed-off-by: Christopher Rauer <redacted>
Signed-off-by: Kang Luwei <redacted>
Signed-off-by: Zhang Yi <redacted>
Signed-off-by: Xiao Guangrong <redacted>
Signed-off-by: Wu Hao <redacted>
---
v2: moved the code to drivers/fpga folder as suggested by Alan Tull.
    switched to GPLv2 license.
    fixed comments from Moritz Fischer.
    fixed kbuild warning, typos and clean up the code.
---
 drivers/fpga/Makefile            |   2 +-
 drivers/fpga/intel-feature-dev.c | 130 ++++++
 drivers/fpga/intel-feature-dev.h | 341 ++++++++++++++++
 drivers/fpga/intel-pcie.c        | 841

++++++++++++++++++++++++++++++++++++++-

quoted

 4 files changed, 1311 insertions(+), 3 deletions(-)
 create mode 100644 drivers/fpga/intel-feature-dev.c
 create mode 100644 drivers/fpga/intel-feature-dev.h

diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 5613133..ad24b3d 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile

@@ -31,4 +31,4 @@ obj-$(CONFIG_OF_FPGA_REGION)          += of-fpga-

region.o

quoted

 # Intel FPGA Support
 obj-$(CONFIG_INTEL_FPGA_PCI)           += intel-fpga-pci.o

-intel-fpga-pci-objs := intel-pcie.o
+intel-fpga-pci-objs := intel-pcie.o intel-feature-dev.o

diff --git a/drivers/fpga/intel-feature-dev.c b/drivers/fpga/intel-feature-dev.c
new file mode 100644
index 0000000..68f9cba
--- /dev/null
+++ b/drivers/fpga/intel-feature-dev.c

@@ -0,0 +1,130 @@
+/*
+ * Intel FPGA Feature Device Driver
+ *
+ * Copyright (C) 2017 Intel Corporation, Inc.
+ *
+ * Authors:
+ *   Kang Luwei <luwei.kang@intel.com>
+ *   Zhang Yi <yi.z.zhang@intel.com>
+ *   Wu Hao <hao.wu@intel.com>
+ *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
+ *
+ * This work is licensed under the terms of the GNU GPL version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include "intel-feature-dev.h"
+
+void feature_platform_data_add(struct feature_platform_data *pdata,
+                              int index, const char *name,
+                              int resource_index, void __iomem *ioaddr)
+{
+       WARN_ON(index >= pdata->num);
+
+       pdata->features[index].name = name;
+       pdata->features[index].resource_index = resource_index;
+       pdata->features[index].ioaddr = ioaddr;
+}
+
+struct feature_platform_data *
+feature_platform_data_alloc_and_init(struct platform_device *dev, int num)
+{
+       struct feature_platform_data *pdata;
+
+       pdata = kzalloc(feature_platform_data_size(num), GFP_KERNEL);
+       if (pdata) {
+               pdata->dev = dev;
+               pdata->num = num;
+               mutex_init(&pdata->lock);
+       }
+
+       return pdata;
+}
+
+int fme_feature_num(void)
+{
+       return FME_FEATURE_ID_MAX;
+}
+
+int port_feature_num(void)
+{
+       return PORT_FEATURE_ID_MAX;
+}
+
+int fpga_port_id(struct platform_device *pdev)
+{
+       struct feature_port_header *port_hdr;
+       struct feature_port_capability capability;
+
+       port_hdr = get_feature_ioaddr_by_index(&pdev->dev,
+                                              PORT_FEATURE_ID_HEADER);
+       WARN_ON(!port_hdr);
+
+       capability.csr = readq(&port_hdr->capability);
+       return capability.port_number;
+}
+EXPORT_SYMBOL_GPL(fpga_port_id);
+
+/*
+ * Enable Port by clear the port soft reset bit, which is set by default.
+ * The User AFU is unable to respond to any MMIO access while in reset.
+ * __fpga_port_enable function should only be used after

__fpga_port_disable

quoted

+ * function.
+ */
+void __fpga_port_enable(struct platform_device *pdev)
+{
+       struct feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
+       struct feature_port_header *port_hdr;
+       struct feature_port_control control;
+
+       WARN_ON(!pdata->disable_count);
+
+       if (--pdata->disable_count != 0)
+               return;
+
+       port_hdr = get_feature_ioaddr_by_index(&pdev->dev,
+                                              PORT_FEATURE_ID_HEADER);
+       WARN_ON(!port_hdr);
+
+       control.csr = readq(&port_hdr->control);
+       control.port_sftrst = 0x0;
+       writeq(control.csr, &port_hdr->control);
+}
+EXPORT_SYMBOL_GPL(__fpga_port_enable);
+
+#define RST_POLL_INVL 10 /* us */
+#define RST_POLL_TIMEOUT 1000 /* us */
+
+int __fpga_port_disable(struct platform_device *pdev)
+{
+       struct feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
+       struct feature_port_header *port_hdr;
+       struct feature_port_control control;
+
+       if (pdata->disable_count++ != 0)
+               return 0;
+
+       port_hdr = get_feature_ioaddr_by_index(&pdev->dev,
+                                              PORT_FEATURE_ID_HEADER);
+       WARN_ON(!port_hdr);
+
+       /* Set port soft reset */
+       control.csr = readq(&port_hdr->control);
+       control.port_sftrst = 0x1;
+       writeq(control.csr, &port_hdr->control);
+
+       /*
+        * HW sets ack bit to 1 when all outstanding requests have been drained
+        * on this port and minimum soft reset pulse width has elapsed.
+        * Driver polls port_soft_reset_ack to determine if reset done by HW.
+        */
+       if (readq_poll_timeout(&port_hdr->control, control.csr,
+                              (control.port_sftrst_ack == 1),
+                              RST_POLL_INVL, RST_POLL_TIMEOUT)) {
+               dev_err(&pdev->dev, "timeout, fail to reset device\n");
+               return -ETIMEDOUT;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(__fpga_port_disable);

diff --git a/drivers/fpga/intel-feature-dev.h b/drivers/fpga/intel-feature-dev.h
new file mode 100644
index 0000000..f67784a
--- /dev/null
+++ b/drivers/fpga/intel-feature-dev.h

@@ -0,0 +1,341 @@
+/*
+ * Intel FPGA Feature Device Driver Header File
+ *
+ * Copyright (C) 2017 Intel Corporation, Inc.
+ *
+ * Authors:
+ *   Kang Luwei <luwei.kang@intel.com>
+ *   Zhang Yi <yi.z.zhang@intel.com>
+ *   Wu Hao <hao.wu@intel.com>
+ *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
+ *
+ * This work is licensed under the terms of the GNU GPL version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#ifndef __INTEL_FPGA_FEATURE_H
+#define __INTEL_FPGA_FEATURE_H
+
+#include <linux/fs.h>
+#include <linux/pci.h>
+#include <linux/uuid.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include <linux/platform_device.h>
+
+#ifndef readq
+static inline u64 readq(void __iomem *addr)
+{
+       return readl(addr) + ((u64)readl(addr + 4) << 32);
+}
+#endif
+
+#ifndef writeq
+static inline void writeq(u64 val, void __iomem *addr)
+{
+       writel((u32) (val), addr);
+       writel((u32) (val >> 32), (addr + 4));
+}
+#endif

Hi Hao,

Was there a reason readq and writeq had to be created for this?  Do
these get used?

Hi Alan

Thanks for your review.

Driver uses writeq and readq to access HW registers.

Actually this is a problem reported by kbuild against the patch set v1[1].
Writeq/readq are missed in some arch, so I added writeq/readq definitions to
resolve this problem following the same way done by some existing drivers.
After recheck this today, I found I should use linux/io-64-nonatomic-lo-hi.h
instead of rewriting them.  I will fix it in the next version.

[1] http://marc.info/?l=linux-kernel&m=149100396816882&w=2

Thanks
Hao

Alan