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 <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: Xiao Guangrong <redacted>
Signed-off-by: Wu Hao <redacted>
Acked-by: Alan Tull <atull@kernel.org>
---
v3: rename driver to dfl-fpga-fme-mgr
    implemented status callback for fpga manager
    rebased due to fpga api changes
v4: rename to dfl-fme-mgr, and fix SPDX license issue
    add pr_credit comments and improve dev_err message
    remove interface_id sysfs interface
    include dfl-fme-pr.h instead of dfl.h
v5: move related register definition from dfl-fme-pr.h to dfl-fme-mgr.c
    use mapped ioaddr passed via pdata for register access.
    rebase due to fpga manager API changes.
    include header file for readq/writeq.
v6: rebase, fix copyright time and add Acked-by from Alan.
---
 drivers/fpga/Kconfig       |   6 +
 drivers/fpga/Makefile      |   1 +
 drivers/fpga/dfl-fme-mgr.c | 334 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 341 insertions(+)
 create mode 100644 drivers/fpga/dfl-fme-mgr.c

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 45e9220..ca97f3c 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig

@@ -156,6 +156,12 @@ 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 FPGA_DFL_PCI
 	tristate "FPGA DFL PCIe Device Driver"
 	depends on PCI && FPGA_DFL

diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index fd334d40..23f41b0 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile

@@ -32,6 +32,7 @@ obj-$(CONFIG_OF_FPGA_REGION)		+= of-fpga-region.o
 # FPGA Device Feature List Support
 obj-$(CONFIG_FPGA_DFL)			+= dfl.o
 obj-$(CONFIG_FPGA_DFL_FME)		+= dfl-fme.o
+obj-$(CONFIG_FPGA_DFL_FME_MGR)		+= dfl-fme-mgr.o
 
 dfl-fme-objs := dfl-fme-main.o dfl-fme-pr.o
 

diff --git a/drivers/fpga/dfl-fme-mgr.c b/drivers/fpga/dfl-fme-mgr.c
new file mode 100644
index 0000000..be0060a
--- /dev/null
+++ b/drivers/fpga/dfl-fme-mgr.c

@@ -0,0 +1,334 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * FPGA Manager Driver for FPGA Management Engine (FME)
+ *
+ * Copyright (C) 2017-2018 Intel Corporation, Inc.
+ *
+ * Authors:
+ *   Kang Luwei <luwei.kang@intel.com>
+ *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
+ *   Wu Hao <hao.wu@intel.com>
+ *   Joseph Grecco <joe.grecco@intel.com>
+ *   Enno Luebbers <enno.luebbers@intel.com>
+ *   Tim Whisonant <tim.whisonant@intel.com>
+ *   Ananda Ravuri <ananda.ravuri@intel.com>
+ *   Christopher Rauer <christopher.rauer@intel.com>
+ *   Henry Mitchel <henry.mitchel@intel.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/module.h>
+#include <linux/iopoll.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/fpga/fpga-mgr.h>
+
+#include "dfl-fme-pr.h"
+
+/* FME Partial Reconfiguration Sub Feature Register Set */
+#define FME_PR_DFH		0x0
+#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
+
+/* FME PR Control Register Bitfield */
+#define FME_PR_CTRL_PR_RST	BIT_ULL(0)  /* Reset PR engine */
+#define FME_PR_CTRL_PR_RSTACK	BIT_ULL(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_ULL(12) /* Start to request PR service */
+#define FME_PR_CTRL_PR_COMPLETE	BIT_ULL(13) /* PR data push completion */
+
+/* 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_ULL(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 */
+/* PR Operation errors detected. */
+#define FME_PR_ERR_OPERATION_ERR	BIT_ULL(0)
+/* CRC error detected. */
+#define FME_PR_ERR_CRC_ERR		BIT_ULL(1)
+/* Incompatible PR bitstream detected. */
+#define FME_PR_ERR_INCOMPATIBLE_BS	BIT_ULL(2)
+/* PR data push protocol violated. */
+#define FME_PR_ERR_PROTOCOL_ERR		BIT_ULL(3)
+/* PR data fifo overflow error detected */
+#define FME_PR_ERR_FIFO_OVERFLOW	BIT_ULL(4)
+
+#define PR_WAIT_TIMEOUT   8000000
+#define PR_HOST_STATUS_IDLE	0
+
+struct fme_mgr_priv {
+	void __iomem *ioaddr;
+	u64 pr_error;
+};
+
+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 supports partial reconfiguration.\n");
+		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, "PR Reset ACK timeout\n");
+		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, "PR Status timeout\n");
+		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");
+
+	/*
+	 * driver can push data to PR hardware using PR_DATA register once HW
+	 * has enough pr_credit (> 1), pr_credit reduces one for every 32bit
+	 * pr data write to PR_DATA register. If pr_credit <= 1, driver needs
+	 * to wait for enough pr_credit from hardware by polling.
+	 */
+	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, "PR_CREDIT timeout\n");
+				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) {
+			WARN_ON(1);