arm: socfpga: stratix10: Add mailbox support for Stratix10 SoC

Add mailbox support for Stratix SoC

Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Chin Liang See <chin.liang.see@intel.com>
Reviewed-by: Marek Vasut <marex@denx.de>
diff --git a/arch/arm/mach-socfpga/mailbox_s10.c b/arch/arm/mach-socfpga/mailbox_s10.c
new file mode 100644
index 0000000..cccd1a4
--- /dev/null
+++ b/arch/arm/mach-socfpga/mailbox_s10.c
@@ -0,0 +1,380 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017-2018 Intel Corporation <www.intel.com>
+ *
+ */
+
+#include <common.h>
+#include <wait_bit.h>
+#include <asm/io.h>
+#include <asm/arch/mailbox_s10.h>
+#include <asm/arch/system_manager.h>
+#include <asm/secure.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define MBOX_READL(reg)			\
+	 readl(SOCFPGA_MAILBOX_ADDRESS + (reg))
+
+#define MBOX_WRITEL(data, reg)		\
+	writel(data, SOCFPGA_MAILBOX_ADDRESS + (reg))
+
+#define MBOX_READ_RESP_BUF(rout)	\
+	MBOX_READL(MBOX_RESP_BUF + ((rout) * sizeof(u32)))
+
+#define MBOX_WRITE_CMD_BUF(data, cin)	\
+	MBOX_WRITEL(data, MBOX_CMD_BUF + ((cin) * sizeof(u32)))
+
+static __always_inline int mbox_polling_resp(u32 rout)
+{
+	u32 rin;
+	unsigned long i = ~0;
+
+	while (i) {
+		rin = MBOX_READL(MBOX_RIN);
+		if (rout != rin)
+			return 0;
+
+		i--;
+	}
+
+	return -ETIMEDOUT;
+}
+
+/* Check for available slot and write to circular buffer.
+ * It also update command valid offset (cin) register.
+ */
+static __always_inline int mbox_fill_cmd_circular_buff(u32 header, u32 len,
+						       u32 *arg)
+{
+	u32 cin;
+	u32 cout;
+	u32 i;
+
+	cin = MBOX_READL(MBOX_CIN) % MBOX_CMD_BUFFER_SIZE;
+	cout = MBOX_READL(MBOX_COUT) % MBOX_CMD_BUFFER_SIZE;
+
+	/* if command buffer is full or not enough free space
+	 * to fit the data
+	 */
+	if (((cin + 1) % MBOX_CMD_BUFFER_SIZE) == cout ||
+	    ((MBOX_CMD_BUFFER_SIZE - cin + cout - 1) %
+	     MBOX_CMD_BUFFER_SIZE) < len)
+		return -ENOMEM;
+
+	/* write header to circular buffer */
+	MBOX_WRITE_CMD_BUF(header, cin++);
+	/* wrapping around when it reach the buffer size */
+	cin %= MBOX_CMD_BUFFER_SIZE;
+
+	/* write arguments */
+	for (i = 0; i < len; i++) {
+		MBOX_WRITE_CMD_BUF(arg[i], cin++);
+		/* wrapping around when it reach the buffer size */
+		cin %= MBOX_CMD_BUFFER_SIZE;
+	}
+
+	/* write command valid offset */
+	MBOX_WRITEL(cin, MBOX_CIN);
+
+	return 0;
+}
+
+/* Check the command and fill it into circular buffer */
+static __always_inline int mbox_prepare_cmd_only(u8 id, u32 cmd,
+						 u8 is_indirect, u32 len,
+						 u32 *arg)
+{
+	u32 header;
+	int ret;
+
+	/* Total length is command + argument length */
+	if ((len + 1) > MBOX_CMD_BUFFER_SIZE)
+		return -EINVAL;
+
+	if (cmd > MBOX_MAX_CMD_INDEX)
+		return -EINVAL;
+
+	header = MBOX_CMD_HEADER(MBOX_CLIENT_ID_UBOOT, id, len,
+				 (is_indirect) ? 1 : 0, cmd);
+
+	ret = mbox_fill_cmd_circular_buff(header, len, arg);
+
+	return ret;
+}
+
+/* Send command only without waiting for responses from SDM */
+static __always_inline int mbox_send_cmd_only_common(u8 id, u32 cmd,
+						     u8 is_indirect, u32 len,
+						     u32 *arg)
+{
+	int ret = mbox_prepare_cmd_only(id, cmd, is_indirect, len, arg);
+	/* write doorbell */
+	MBOX_WRITEL(1, MBOX_DOORBELL_TO_SDM);
+
+	return ret;
+}
+
+/* Return number of responses received in buffer */
+static __always_inline int __mbox_rcv_resp(u32 *resp_buf, u32 resp_buf_max_len)
+{
+	u32 rin;
+	u32 rout;
+	u32 resp_len = 0;
+
+	/* clear doorbell from SDM if it was SET */
+	if (MBOX_READL(MBOX_DOORBELL_FROM_SDM) & 1)
+		MBOX_WRITEL(0, MBOX_DOORBELL_FROM_SDM);
+
+	/* read current response offset */
+	rout = MBOX_READL(MBOX_ROUT);
+	/* read response valid offset */
+	rin = MBOX_READL(MBOX_RIN);
+
+	while (rin != rout && (resp_len < resp_buf_max_len)) {
+		/* Response received */
+		if (resp_buf)
+			resp_buf[resp_len++] = MBOX_READ_RESP_BUF(rout);
+
+		rout++;
+		/* wrapping around when it reach the buffer size */
+		rout %= MBOX_RESP_BUFFER_SIZE;
+		/* update next ROUT */
+		MBOX_WRITEL(rout, MBOX_ROUT);
+	}
+
+	return resp_len;
+}
+
+/* Support one command and up to 31 words argument length only */
+static __always_inline int mbox_send_cmd_common(u8 id, u32 cmd, u8 is_indirect,
+						u32 len, u32 *arg, u8 urgent,
+						u32 *resp_buf_len,
+						u32 *resp_buf)
+{
+	u32 rin;
+	u32 resp;
+	u32 rout;
+	u32 status;
+	u32 resp_len;
+	u32 buf_len;
+	int ret;
+
+	ret = mbox_prepare_cmd_only(id, cmd, is_indirect, len, arg);
+	if (ret)
+		return ret;
+
+	if (urgent) {
+		/* Read status because it is toggled */
+		status = MBOX_READL(MBOX_STATUS) & MBOX_STATUS_UA_MSK;
+		/* Send command as urgent command */
+		MBOX_WRITEL(1, MBOX_URG);
+	}
+
+	/* write doorbell */
+	MBOX_WRITEL(1, MBOX_DOORBELL_TO_SDM);
+
+	while (1) {
+		ret = ~0;
+
+		/* Wait for doorbell from SDM */
+		while (!MBOX_READL(MBOX_DOORBELL_FROM_SDM) && ret--)
+			;
+		if (!ret)
+			return -ETIMEDOUT;
+
+		/* clear interrupt */
+		MBOX_WRITEL(0, MBOX_DOORBELL_FROM_SDM);
+
+		if (urgent) {
+			u32 new_status = MBOX_READL(MBOX_STATUS);
+			/* urgent command doesn't have response */
+			MBOX_WRITEL(0, MBOX_URG);
+			/* Urgent ACK is toggled */
+			if ((new_status & MBOX_STATUS_UA_MSK) ^ status)
+				return 0;
+
+			return -ECOMM;
+		}
+
+		/* read current response offset */
+		rout = MBOX_READL(MBOX_ROUT);
+
+		/* read response valid offset */
+		rin = MBOX_READL(MBOX_RIN);
+
+		if (rout != rin) {
+			/* Response received */
+			resp = MBOX_READ_RESP_BUF(rout);
+			rout++;
+			/* wrapping around when it reach the buffer size */
+			rout %= MBOX_RESP_BUFFER_SIZE;
+			/* update next ROUT */
+			MBOX_WRITEL(rout, MBOX_ROUT);
+
+			/* check client ID and ID */
+			if ((MBOX_RESP_CLIENT_GET(resp) ==
+			     MBOX_CLIENT_ID_UBOOT) &&
+			    (MBOX_RESP_ID_GET(resp) == id)) {
+				ret = MBOX_RESP_ERR_GET(resp);
+				if (ret)
+					return ret;
+
+				if (resp_buf_len) {
+					buf_len = *resp_buf_len;
+					*resp_buf_len = 0;
+				} else {
+					buf_len = 0;
+				}
+
+				resp_len = MBOX_RESP_LEN_GET(resp);
+				while (resp_len) {
+					ret = mbox_polling_resp(rout);
+					if (ret)
+						return ret;
+					/* we need to process response buffer
+					 * even caller doesn't need it
+					 */
+					resp = MBOX_READ_RESP_BUF(rout);
+					rout++;
+					resp_len--;
+					rout %= MBOX_RESP_BUFFER_SIZE;
+					MBOX_WRITEL(rout, MBOX_ROUT);
+					if (buf_len) {
+						/* copy response to buffer */
+						resp_buf[*resp_buf_len] = resp;
+						(*resp_buf_len)++;
+						buf_len--;
+					}
+				}
+				return ret;
+			}
+		}
+	};
+
+	return -EIO;
+}
+
+int mbox_init(void)
+{
+	int ret;
+
+	/* enable mailbox interrupts */
+	MBOX_WRITEL(MBOX_ALL_INTRS, MBOX_FLAGS);
+
+	/* Ensure urgent request is cleared */
+	MBOX_WRITEL(0, MBOX_URG);
+
+	/* Ensure the Doorbell Interrupt is cleared */
+	MBOX_WRITEL(0, MBOX_DOORBELL_FROM_SDM);
+
+	ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_RESTART, MBOX_CMD_DIRECT, 0,
+			    NULL, 1, 0, NULL);
+	if (ret)
+		return ret;
+
+	/* Renable mailbox interrupts after MBOX_RESTART */
+	MBOX_WRITEL(MBOX_ALL_INTRS, MBOX_FLAGS);
+
+	return 0;
+}
+
+#ifdef CONFIG_CADENCE_QSPI
+int mbox_qspi_close(void)
+{
+	return mbox_send_cmd(MBOX_ID_UBOOT, MBOX_QSPI_CLOSE, MBOX_CMD_DIRECT,
+			     0, NULL, 0, 0, NULL);
+}
+
+int mbox_qspi_open(void)
+{
+	static const struct socfpga_system_manager *sysmgr_regs =
+		(struct socfpga_system_manager *)SOCFPGA_SYSMGR_ADDRESS;
+
+	int ret;
+	u32 resp_buf[1];
+	u32 resp_buf_len;
+
+	ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_QSPI_OPEN, MBOX_CMD_DIRECT,
+			    0, NULL, 0, 0, NULL);
+	if (ret) {
+		/* retry again by closing and reopen the QSPI again */
+		ret = mbox_qspi_close();
+		if (ret)
+			return ret;
+
+		ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_QSPI_OPEN,
+				    MBOX_CMD_DIRECT, 0, NULL, 0, 0, NULL);
+		if (ret)
+			return ret;
+	}
+
+	/* HPS will directly control the QSPI controller, no longer mailbox */
+	resp_buf_len = 1;
+	ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_QSPI_DIRECT, MBOX_CMD_DIRECT,
+			    0, NULL, 0, (u32 *)&resp_buf_len,
+			    (u32 *)&resp_buf);
+	if (ret)
+		goto error;
+
+	/* We are getting QSPI ref clock and set into sysmgr boot register */
+	printf("QSPI: Reference clock at %d Hz\n", resp_buf[0]);
+	writel(resp_buf[0], &sysmgr_regs->boot_scratch_cold0);
+
+	return 0;
+
+error:
+	mbox_qspi_close();
+
+	return ret;
+}
+#endif /* CONFIG_CADENCE_QSPI */
+
+int mbox_reset_cold(void)
+{
+	int ret;
+
+	ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_REBOOT_HPS, MBOX_CMD_DIRECT,
+			    0, NULL, 0, 0, NULL);
+	if (ret) {
+		/* mailbox sent failure, wait for watchdog to kick in */
+		hang();
+	}
+	return 0;
+}
+
+int mbox_send_cmd(u8 id, u32 cmd, u8 is_indirect, u32 len, u32 *arg,
+		  u8 urgent, u32 *resp_buf_len, u32 *resp_buf)
+{
+	return mbox_send_cmd_common(id, cmd, is_indirect, len, arg, urgent,
+			       resp_buf_len, resp_buf);
+}
+
+int __secure mbox_send_cmd_psci(u8 id, u32 cmd, u8 is_indirect, u32 len,
+				u32 *arg, u8 urgent, u32 *resp_buf_len,
+				u32 *resp_buf)
+{
+	return mbox_send_cmd_common(id, cmd, is_indirect, len, arg, urgent,
+			       resp_buf_len, resp_buf);
+}
+
+int mbox_send_cmd_only(u8 id, u32 cmd, u8 is_indirect, u32 len, u32 *arg)
+{
+	return mbox_send_cmd_only_common(id, cmd, is_indirect, len, arg);
+}
+
+int __secure mbox_send_cmd_only_psci(u8 id, u32 cmd, u8 is_indirect, u32 len,
+				     u32 *arg)
+{
+	return mbox_send_cmd_only_common(id, cmd, is_indirect, len, arg);
+}
+
+int mbox_rcv_resp(u32 *resp_buf, u32 resp_buf_max_len)
+{
+	return __mbox_rcv_resp(resp_buf, resp_buf_max_len);
+}
+
+int __secure mbox_rcv_resp_psci(u32 *resp_buf, u32 resp_buf_max_len)
+{
+	return __mbox_rcv_resp(resp_buf, resp_buf_max_len);
+}