kernel

linux-6.8.1/drivers/fpga/altera-pr-ip-core.c

@@ -0,0 +1,201 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Altera Partial Reconfiguration IP Core
+ *
+ * Copyright (C) 2016-2017 Intel Corporation
+ *
+ * Based on socfpga-a10.c Copyright (C) 2015-2016 Altera Corporation
+ *  by Alan Tull <atull@opensource.altera.com>
+ */
+#include <linux/delay.h>
+#include <linux/fpga/altera-pr-ip-core.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/module.h>
+
+#define ALT_PR_DATA_OFST		0x00
+#define ALT_PR_CSR_OFST			0x04
+
+#define ALT_PR_CSR_PR_START		BIT(0)
+#define ALT_PR_CSR_STATUS_SFT		2
+#define ALT_PR_CSR_STATUS_MSK		(7 << ALT_PR_CSR_STATUS_SFT)
+#define ALT_PR_CSR_STATUS_NRESET	(0 << ALT_PR_CSR_STATUS_SFT)
+#define ALT_PR_CSR_STATUS_PR_ERR	(1 << ALT_PR_CSR_STATUS_SFT)
+#define ALT_PR_CSR_STATUS_CRC_ERR	(2 << ALT_PR_CSR_STATUS_SFT)
+#define ALT_PR_CSR_STATUS_BAD_BITS	(3 << ALT_PR_CSR_STATUS_SFT)
+#define ALT_PR_CSR_STATUS_PR_IN_PROG	(4 << ALT_PR_CSR_STATUS_SFT)
+#define ALT_PR_CSR_STATUS_PR_SUCCESS	(5 << ALT_PR_CSR_STATUS_SFT)
+
+struct alt_pr_priv {
+	void __iomem *reg_base;
+};
+
+static enum fpga_mgr_states alt_pr_fpga_state(struct fpga_manager *mgr)
+{
+	struct alt_pr_priv *priv = mgr->priv;
+	const char *err = "unknown";
+	enum fpga_mgr_states ret = FPGA_MGR_STATE_UNKNOWN;
+	u32 val;
+
+	val = readl(priv->reg_base + ALT_PR_CSR_OFST);
+
+	val &= ALT_PR_CSR_STATUS_MSK;
+
+	switch (val) {
+	case ALT_PR_CSR_STATUS_NRESET:
+		return FPGA_MGR_STATE_RESET;
+
+	case ALT_PR_CSR_STATUS_PR_ERR:
+		err = "pr error";
+		ret = FPGA_MGR_STATE_WRITE_ERR;
+		break;
+
+	case ALT_PR_CSR_STATUS_CRC_ERR:
+		err = "crc error";
+		ret = FPGA_MGR_STATE_WRITE_ERR;
+		break;
+
+	case ALT_PR_CSR_STATUS_BAD_BITS:
+		err = "bad bits";
+		ret = FPGA_MGR_STATE_WRITE_ERR;
+		break;
+
+	case ALT_PR_CSR_STATUS_PR_IN_PROG:
+		return FPGA_MGR_STATE_WRITE;
+
+	case ALT_PR_CSR_STATUS_PR_SUCCESS:
+		return FPGA_MGR_STATE_OPERATING;
+
+	default:
+		break;
+	}
+
+	dev_err(&mgr->dev, "encountered error code %d (%s) in %s()\n",
+		val, err, __func__);
+	return ret;
+}
+
+static int alt_pr_fpga_write_init(struct fpga_manager *mgr,
+				  struct fpga_image_info *info,
+				  const char *buf, size_t count)
+{
+	struct alt_pr_priv *priv = mgr->priv;
+	u32 val;
+
+	if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
+		dev_err(&mgr->dev, "%s Partial Reconfiguration flag not set\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	val = readl(priv->reg_base + ALT_PR_CSR_OFST);
+
+	if (val & ALT_PR_CSR_PR_START) {
+		dev_err(&mgr->dev,
+			"%s Partial Reconfiguration already started\n",
+		       __func__);
+		return -EINVAL;
+	}
+
+	writel(val | ALT_PR_CSR_PR_START, priv->reg_base + ALT_PR_CSR_OFST);
+
+	return 0;
+}
+
+static int alt_pr_fpga_write(struct fpga_manager *mgr, const char *buf,
+			     size_t count)
+{
+	struct alt_pr_priv *priv = mgr->priv;
+	u32 *buffer_32 = (u32 *)buf;
+	size_t i = 0;
+
+	if (!count)
+		return -EINVAL;
+
+	/* Write out the complete 32-bit chunks */
+	while (count >= sizeof(u32)) {
+		writel(buffer_32[i++], priv->reg_base);
+		count -= sizeof(u32);
+	}
+
+	/* Write out remaining non 32-bit chunks */
+	switch (count) {
+	case 3:
+		writel(buffer_32[i++] & 0x00ffffff, priv->reg_base);
+		break;
+	case 2:
+		writel(buffer_32[i++] & 0x0000ffff, priv->reg_base);
+		break;
+	case 1:
+		writel(buffer_32[i++] & 0x000000ff, priv->reg_base);
+		break;
+	case 0:
+		break;
+	default:
+		/* This will never happen */
+		return -EFAULT;
+	}
+
+	if (alt_pr_fpga_state(mgr) == FPGA_MGR_STATE_WRITE_ERR)
+		return -EIO;
+
+	return 0;
+}
+
+static int alt_pr_fpga_write_complete(struct fpga_manager *mgr,
+				      struct fpga_image_info *info)
+{
+	u32 i = 0;
+
+	do {
+		switch (alt_pr_fpga_state(mgr)) {
+		case FPGA_MGR_STATE_WRITE_ERR:
+			return -EIO;
+
+		case FPGA_MGR_STATE_OPERATING:
+			dev_info(&mgr->dev,
+				 "successful partial reconfiguration\n");
+			return 0;
+
+		default:
+			break;
+		}
+		udelay(1);
+	} while (info->config_complete_timeout_us > i++);
+
+	dev_err(&mgr->dev, "timed out waiting for write to complete\n");
+	return -ETIMEDOUT;
+}
+
+static const struct fpga_manager_ops alt_pr_ops = {
+	.state = alt_pr_fpga_state,
+	.write_init = alt_pr_fpga_write_init,
+	.write = alt_pr_fpga_write,
+	.write_complete = alt_pr_fpga_write_complete,
+};
+
+int alt_pr_register(struct device *dev, void __iomem *reg_base)
+{
+	struct alt_pr_priv *priv;
+	struct fpga_manager *mgr;
+	u32 val;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->reg_base = reg_base;
+
+	val = readl(priv->reg_base + ALT_PR_CSR_OFST);
+
+	dev_dbg(dev, "%s status=%d start=%d\n", __func__,
+		(val & ALT_PR_CSR_STATUS_MSK) >> ALT_PR_CSR_STATUS_SFT,
+		(int)(val & ALT_PR_CSR_PR_START));
+
+	mgr = devm_fpga_mgr_register(dev, dev_name(dev), &alt_pr_ops, priv);
+	return PTR_ERR_OR_ZERO(mgr);
+}
+EXPORT_SYMBOL_GPL(alt_pr_register);
+
+MODULE_AUTHOR("Matthew Gerlach <matthew.gerlach@linux.intel.com>");
+MODULE_DESCRIPTION("Altera Partial Reconfiguration IP Core");
+MODULE_LICENSE("GPL v2");