Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 336 insertions, 0 deletions

diff --git a/drivers/vdpa/solidrun/snet_ctrl.c b/drivers/vdpa/solidrun/snet_ctrl.c
new file mode 100644
index 000000000..3cef2571d
--- /dev/null
+++ b/drivers/vdpa/solidrun/snet_ctrl.c
@@ -0,0 +1,336 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SolidRun DPU driver for control plane
+ *
+ * Copyright (C) 2022-2023 SolidRun
+ *
+ * Author: Alvaro Karsz <alvaro.karsz@solid-run.com>
+ *
+ */
+
+#include <linux/iopoll.h>
+
+#include "snet_vdpa.h"
+
+enum snet_ctrl_opcodes {
+	SNET_CTRL_OP_DESTROY = 1,
+	SNET_CTRL_OP_READ_VQ_STATE,
+	SNET_CTRL_OP_SUSPEND,
+	SNET_CTRL_OP_RESUME,
+};
+
+#define SNET_CTRL_TIMEOUT	        2000000
+
+#define SNET_CTRL_DATA_SIZE_MASK	0x0000FFFF
+#define SNET_CTRL_IN_PROCESS_MASK	0x00010000
+#define SNET_CTRL_CHUNK_RDY_MASK	0x00020000
+#define SNET_CTRL_ERROR_MASK		0x0FFC0000
+
+#define SNET_VAL_TO_ERR(val)		(-(((val) & SNET_CTRL_ERROR_MASK) >> 18))
+#define SNET_EMPTY_CTRL(val)		(((val) & SNET_CTRL_ERROR_MASK) || \
+						!((val) & SNET_CTRL_IN_PROCESS_MASK))
+#define SNET_DATA_READY(val)		((val) & (SNET_CTRL_ERROR_MASK | SNET_CTRL_CHUNK_RDY_MASK))
+
+/* Control register used to read data from the DPU */
+struct snet_ctrl_reg_ctrl {
+	/* Chunk size in 4B words */
+	u16 data_size;
+	/* We are in the middle of a command */
+	u16 in_process:1;
+	/* A data chunk is ready and can be consumed */
+	u16 chunk_ready:1;
+	/* Error code */
+	u16 error:10;
+	/* Saved for future usage */
+	u16 rsvd:4;
+};
+
+/* Opcode register */
+struct snet_ctrl_reg_op {
+	u16 opcode;
+	/* Only if VQ index is relevant for the command */
+	u16 vq_idx;
+};
+
+struct snet_ctrl_regs {
+	struct snet_ctrl_reg_op op;
+	struct snet_ctrl_reg_ctrl ctrl;
+	u32 rsvd;
+	u32 data[];
+};
+
+static struct snet_ctrl_regs __iomem *snet_get_ctrl(struct snet *snet)
+{
+	return snet->bar + snet->psnet->cfg.ctrl_off;
+}
+
+static int snet_wait_for_empty_ctrl(struct snet_ctrl_regs __iomem *regs)
+{
+	u32 val;
+
+	return readx_poll_timeout(ioread32, &regs->ctrl, val, SNET_EMPTY_CTRL(val), 10,
+				  SNET_CTRL_TIMEOUT);
+}
+
+static int snet_wait_for_empty_op(struct snet_ctrl_regs __iomem *regs)
+{
+	u32 val;
+
+	return readx_poll_timeout(ioread32, &regs->op, val, !val, 10, SNET_CTRL_TIMEOUT);
+}
+
+static int snet_wait_for_data(struct snet_ctrl_regs __iomem *regs)
+{
+	u32 val;
+
+	return readx_poll_timeout(ioread32, &regs->ctrl, val, SNET_DATA_READY(val), 10,
+				  SNET_CTRL_TIMEOUT);
+}
+
+static u32 snet_read32_word(struct snet_ctrl_regs __iomem *ctrl_regs, u16 word_idx)
+{
+	return ioread32(&ctrl_regs->data[word_idx]);
+}
+
+static u32 snet_read_ctrl(struct snet_ctrl_regs __iomem *ctrl_regs)
+{
+	return ioread32(&ctrl_regs->ctrl);
+}
+
+static void snet_write_ctrl(struct snet_ctrl_regs __iomem *ctrl_regs, u32 val)
+{
+	iowrite32(val, &ctrl_regs->ctrl);
+}
+
+static void snet_write_op(struct snet_ctrl_regs __iomem *ctrl_regs, u32 val)
+{
+	iowrite32(val, &ctrl_regs->op);
+}
+
+static int snet_wait_for_dpu_completion(struct snet_ctrl_regs __iomem *ctrl_regs)
+{
+	/* Wait until the DPU finishes completely.
+	 * It will clear the opcode register.
+	 */
+	return snet_wait_for_empty_op(ctrl_regs);
+}
+
+/* Reading ctrl from the DPU:
+ * buf_size must be 4B aligned
+ *
+ * Steps:
+ *
+ * (1) Verify that the DPU is not in the middle of another operation by
+ *     reading the in_process and error bits in the control register.
+ * (2) Write the request opcode and the VQ idx in the opcode register
+ *     and write the buffer size in the control register.
+ * (3) Start readind chunks of data, chunk_ready bit indicates that a
+ *     data chunk is available, we signal that we read the data by clearing the bit.
+ * (4) Detect that the transfer is completed when the in_process bit
+ *     in the control register is cleared or when the an error appears.
+ */
+static int snet_ctrl_read_from_dpu(struct snet *snet, u16 opcode, u16 vq_idx, void *buffer,
+				   u32 buf_size)
+{
+	struct pci_dev *pdev = snet->pdev;
+	struct snet_ctrl_regs __iomem *regs = snet_get_ctrl(snet);
+	u32 *bfr_ptr = (u32 *)buffer;
+	u32 val;
+	u16 buf_words;
+	int ret;
+	u16 words, i, tot_words = 0;
+
+	/* Supported for config 2+ */
+	if (!SNET_CFG_VER(snet, 2))
+		return -EOPNOTSUPP;
+
+	if (!IS_ALIGNED(buf_size, 4))
+		return -EINVAL;
+
+	mutex_lock(&snet->ctrl_lock);
+
+	buf_words = buf_size / 4;
+
+	/* Make sure control register is empty */
+	ret = snet_wait_for_empty_ctrl(regs);
+	if (ret) {
+		SNET_WARN(pdev, "Timeout waiting for previous control data to be consumed\n");
+		goto exit;
+	}
+
+	/* We need to write the buffer size in the control register, and the opcode + vq index in
+	 * the opcode register.
+	 * We use a spinlock to serialize the writes.
+	 */
+	spin_lock(&snet->ctrl_spinlock);
+
+	snet_write_ctrl(regs, buf_words);
+	snet_write_op(regs, opcode | (vq_idx << 16));
+
+	spin_unlock(&snet->ctrl_spinlock);
+
+	while (buf_words != tot_words) {
+		ret = snet_wait_for_data(regs);
+		if (ret) {
+			SNET_WARN(pdev, "Timeout waiting for control data\n");
+			goto exit;
+		}
+
+		val = snet_read_ctrl(regs);
+
+		/* Error? */
+		if (val & SNET_CTRL_ERROR_MASK) {
+			ret = SNET_VAL_TO_ERR(val);
+			SNET_WARN(pdev, "Error while reading control data from DPU, err %d\n", ret);
+			goto exit;
+		}
+
+		words = min_t(u16, val & SNET_CTRL_DATA_SIZE_MASK, buf_words - tot_words);
+
+		for (i = 0; i < words; i++) {
+			*bfr_ptr = snet_read32_word(regs, i);
+			bfr_ptr++;
+		}
+
+		tot_words += words;
+
+		/* Is the job completed? */
+		if (!(val & SNET_CTRL_IN_PROCESS_MASK))
+			break;
+
+		/* Clear the chunk ready bit and continue */
+		val &= ~SNET_CTRL_CHUNK_RDY_MASK;
+		snet_write_ctrl(regs, val);
+	}
+
+	ret = snet_wait_for_dpu_completion(regs);
+	if (ret)
+		SNET_WARN(pdev, "Timeout waiting for the DPU to complete a control command\n");
+
+exit:
+	mutex_unlock(&snet->ctrl_lock);
+	return ret;
+}
+
+/* Send a control message to the DPU using the old mechanism
+ * used with config version 1.
+ */
+static int snet_send_ctrl_msg_old(struct snet *snet, u32 opcode)
+{
+	struct pci_dev *pdev = snet->pdev;
+	struct snet_ctrl_regs __iomem *regs = snet_get_ctrl(snet);
+	int ret;
+
+	mutex_lock(&snet->ctrl_lock);
+
+	/* Old mechanism uses just 1 register, the opcode register.
+	 * Make sure that the opcode register is empty, and that the DPU isn't
+	 * processing an old message.
+	 */
+	ret = snet_wait_for_empty_op(regs);
+	if (ret) {
+		SNET_WARN(pdev, "Timeout waiting for previous control message to be ACKed\n");
+		goto exit;
+	}
+
+	/* Write the message */
+	snet_write_op(regs, opcode);
+
+	/* DPU ACKs the message by clearing the opcode register */
+	ret = snet_wait_for_empty_op(regs);
+	if (ret)
+		SNET_WARN(pdev, "Timeout waiting for a control message to be ACKed\n");
+
+exit:
+	mutex_unlock(&snet->ctrl_lock);
+	return ret;
+}
+
+/* Send a control message to the DPU.
+ * A control message is a message without payload.
+ */
+static int snet_send_ctrl_msg(struct snet *snet, u16 opcode, u16 vq_idx)
+{
+	struct pci_dev *pdev = snet->pdev;
+	struct snet_ctrl_regs __iomem *regs = snet_get_ctrl(snet);
+	u32 val;
+	int ret;
+
+	/* If config version is not 2+, use the old mechanism */
+	if (!SNET_CFG_VER(snet, 2))
+		return snet_send_ctrl_msg_old(snet, opcode);
+
+	mutex_lock(&snet->ctrl_lock);
+
+	/* Make sure control register is empty */
+	ret = snet_wait_for_empty_ctrl(regs);
+	if (ret) {
+		SNET_WARN(pdev, "Timeout waiting for previous control data to be consumed\n");
+		goto exit;
+	}
+
+	/* We need to clear the control register and write the opcode + vq index in the opcode
+	 * register.
+	 * We use a spinlock to serialize the writes.
+	 */
+	spin_lock(&snet->ctrl_spinlock);
+
+	snet_write_ctrl(regs, 0);
+	snet_write_op(regs, opcode | (vq_idx << 16));
+
+	spin_unlock(&snet->ctrl_spinlock);
+
+	/* The DPU ACKs control messages by setting the chunk ready bit
+	 * without data.
+	 */
+	ret = snet_wait_for_data(regs);
+	if (ret) {
+		SNET_WARN(pdev, "Timeout waiting for control message to be ACKed\n");
+		goto exit;
+	}
+
+	/* Check for errors */
+	val = snet_read_ctrl(regs);
+	ret = SNET_VAL_TO_ERR(val);
+
+	/* Clear the chunk ready bit */
+	val &= ~SNET_CTRL_CHUNK_RDY_MASK;
+	snet_write_ctrl(regs, val);
+
+	ret = snet_wait_for_dpu_completion(regs);
+	if (ret)
+		SNET_WARN(pdev, "Timeout waiting for DPU to complete a control command, err %d\n",
+			  ret);
+
+exit:
+	mutex_unlock(&snet->ctrl_lock);
+	return ret;
+}
+
+void snet_ctrl_clear(struct snet *snet)
+{
+	struct snet_ctrl_regs __iomem *regs = snet_get_ctrl(snet);
+
+	snet_write_op(regs, 0);
+}
+
+int snet_destroy_dev(struct snet *snet)
+{
+	return snet_send_ctrl_msg(snet, SNET_CTRL_OP_DESTROY, 0);
+}
+
+int snet_read_vq_state(struct snet *snet, u16 idx, struct vdpa_vq_state *state)
+{
+	return snet_ctrl_read_from_dpu(snet, SNET_CTRL_OP_READ_VQ_STATE, idx, state,
+				       sizeof(*state));
+}
+
+int snet_suspend_dev(struct snet *snet)
+{
+	return snet_send_ctrl_msg(snet, SNET_CTRL_OP_SUSPEND, 0);
+}
+
+int snet_resume_dev(struct snet *snet)
+{
+	return snet_send_ctrl_msg(snet, SNET_CTRL_OP_RESUME, 0);
+}