fpga: dfl: add fpga manager platform driver for FME

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@intel.com>
Signed-off-by: Enno Luebbers <enno.luebbers@intel.com>
Signed-off-by: Shiva Rao <shiva.rao@intel.com>
Signed-off-by: Christopher Rauer <christopher.rauer@intel.com>
Signed-off-by: Kang Luwei <luwei.kang@intel.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 334 insertions, 0 deletions

diff --git a/drivers/fpga/dfl-fme-mgr.c b/drivers/fpga/dfl-fme-mgr.c
new file mode 100644
index 000000000000..df843b51c663
--- /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) {
+			dev_err(dev, "Invaild PR bitstream size\n");
+			return -EINVAL;
+		}
+
+		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++;
+	}
+
+	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, "PR Completion ACK timeout.\n");
+		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 dfl_fme_mgr_pdata *pdata = dev_get_platdata(&pdev->dev);
+	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;
+
+	if (pdata->ioaddr)
+		priv->ioaddr = pdata->ioaddr;
+
+	if (!priv->ioaddr) {
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+		priv->ioaddr = devm_ioremap_resource(dev, res);
+		if (IS_ERR(priv->ioaddr))
+			return PTR_ERR(priv->ioaddr);
+	}
+
+	mgr = fpga_mgr_create(dev, "DFL FME FPGA Manager",
+			      &fme_mgr_ops, priv);
+	if (!mgr)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, mgr);
+
+	ret = fpga_mgr_register(mgr);
+	if (ret)
+		fpga_mgr_free(mgr);
+
+	return ret;
+}
+
+static int fme_mgr_remove(struct platform_device *pdev)
+{
+	struct fpga_manager *mgr = platform_get_drvdata(pdev);
+
+	fpga_mgr_unregister(mgr);
+
+	return 0;
+}
+
+static struct platform_driver fme_mgr_driver = {
+	.driver	= {
+		.name    = DFL_FPGA_FME_MGR,
+	},
+	.probe   = fme_mgr_probe,
+	.remove  = fme_mgr_remove,
+};
+
+module_platform_driver(fme_mgr_driver);
+
+MODULE_DESCRIPTION("FPGA Manager for DFL FPGA Management Engine");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:dfl-fme-mgr");