1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/net/mscc_eswitch/mscc_xfer.c b/drivers/net/mscc_eswitch/mscc_xfer.c
new file mode 100644
index 0000000000..f412901f1d
--- /dev/null
+++ b/drivers/net/mscc_eswitch/mscc_xfer.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2018 Microsemi Corporation
+ */
+
+#include <linux/io.h>
+#include "mscc_xfer.h"
+
+#define QS_XTR_FLUSH_FLUSH		GENMASK(1, 0)
+#define QS_INJ_CTRL_GAP_SIZE(x)		((x) << 21)
+#define QS_INJ_CTRL_EOF			BIT(19)
+#define QS_INJ_CTRL_SOF			BIT(18)
+#define QS_INJ_CTRL_VLD_BYTES(x)	((x) << 16)
+
+#define XTR_EOF_0     ntohl(0x80000000u)
+#define XTR_EOF_1     ntohl(0x80000001u)
+#define XTR_EOF_2     ntohl(0x80000002u)
+#define XTR_EOF_3     ntohl(0x80000003u)
+#define XTR_PRUNED    ntohl(0x80000004u)
+#define XTR_ABORT     ntohl(0x80000005u)
+#define XTR_ESCAPE    ntohl(0x80000006u)
+#define XTR_NOT_READY ntohl(0x80000007u)
+
+#define BUF_CELL_SZ		60
+#define XTR_VALID_BYTES(x)	(4 - ((x) & 3))
+
+int mscc_send(void __iomem *regs, const unsigned long *mscc_qs_offset,
+	      u32 *ifh, size_t ifh_len, u32 *buff, size_t buff_len)
+{
+	int i, count = (buff_len + 3) / 4, last = buff_len % 4;
+
+	writel(QS_INJ_CTRL_GAP_SIZE(1) | QS_INJ_CTRL_SOF,
+	       regs + mscc_qs_offset[MSCC_QS_INJ_CTRL]);
+
+	for (i = 0; i < ifh_len; i++)
+		writel(ifh[i], regs + mscc_qs_offset[MSCC_QS_INJ_WR]);
+
+	for (i = 0; i < count; i++)
+		writel(buff[i], regs + mscc_qs_offset[MSCC_QS_INJ_WR]);
+
+	/* Add padding */
+	while (i < (BUF_CELL_SZ / 4)) {
+		writel(0, regs + mscc_qs_offset[MSCC_QS_INJ_WR]);
+		i++;
+	}
+
+	/* Indicate EOF and valid bytes in last word */
+	writel(QS_INJ_CTRL_GAP_SIZE(1) |
+	       QS_INJ_CTRL_VLD_BYTES(buff_len < BUF_CELL_SZ ? 0 : last) |
+	       QS_INJ_CTRL_EOF, regs + mscc_qs_offset[MSCC_QS_INJ_CTRL]);
+
+	/* Add dummy CRC */
+	writel(0, regs + mscc_qs_offset[MSCC_QS_INJ_WR]);
+
+	return 0;
+}
+
+int mscc_recv(void __iomem *regs, const unsigned long *mscc_qs_offset,
+	      u32 *rxbuf, size_t ifh_len, bool byte_swap)
+{
+	u8 grp = 0; /* Recv everything on CPU group 0 */
+	int i, byte_cnt = 0;
+	bool eof_flag = false, pruned_flag = false, abort_flag = false;
+
+	if (!(readl(regs + mscc_qs_offset[MSCC_QS_XTR_DATA_PRESENT]) &
+	      BIT(grp)))
+		return -EAGAIN;
+
+	/* skip IFH */
+	for (i = 0; i < ifh_len; i++)
+		readl(regs + mscc_qs_offset[MSCC_QS_XTR_RD]);
+
+	while (!eof_flag) {
+		u32 val = readl(regs + mscc_qs_offset[MSCC_QS_XTR_RD]);
+		u32 cmp = val;
+
+		if (byte_swap)
+			cmp = ntohl(val);
+
+		switch (cmp) {
+		case XTR_NOT_READY:
+			debug("%d NOT_READY...?\n", byte_cnt);
+			break;
+		case XTR_ABORT:
+			*rxbuf = readl(regs + mscc_qs_offset[MSCC_QS_XTR_RD]);
+			abort_flag = true;
+			eof_flag = true;
+			debug("XTR_ABORT\n");
+			break;
+		case XTR_EOF_0:
+		case XTR_EOF_1:
+		case XTR_EOF_2:
+		case XTR_EOF_3:
+			byte_cnt += XTR_VALID_BYTES(val);
+			*rxbuf = readl(regs + mscc_qs_offset[MSCC_QS_XTR_RD]);
+			eof_flag = true;
+			debug("EOF\n");
+			break;
+		case XTR_PRUNED:
+			/* But get the last 4 bytes as well */
+			eof_flag = true;
+			pruned_flag = true;
+			debug("PRUNED\n");
+			/* fallthrough */
+		case XTR_ESCAPE:
+			*rxbuf = readl(regs + mscc_qs_offset[MSCC_QS_XTR_RD]);
+			byte_cnt += 4;
+			rxbuf++;
+			debug("ESCAPED\n");
+			break;
+		default:
+			*rxbuf = val;
+			byte_cnt += 4;
+			rxbuf++;
+		}
+	}
+
+	if (abort_flag || pruned_flag || !eof_flag) {
+		debug("Discarded frame: abort:%d pruned:%d eof:%d\n",
+		      abort_flag, pruned_flag, eof_flag);
+		return -EAGAIN;
+	}
+
+	return byte_cnt;
+}
+
+void mscc_flush(void __iomem *regs, const unsigned long *mscc_qs_offset)
+{
+	/* All Queues flush */
+	setbits_le32(regs + mscc_qs_offset[MSCC_QS_XTR_FLUSH],
+		     QS_XTR_FLUSH_FLUSH);
+
+	/* Allow to drain */
+	mdelay(1);
+
+	/* All Queues normal */
+	clrbits_le32(regs + mscc_qs_offset[MSCC_QS_XTR_FLUSH],
+		     QS_XTR_FLUSH_FLUSH);
+}