mailbox: Add Broadcom PDC mailbox driver

The Broadcom PDC mailbox driver is a mailbox controller that
manages data transfers to and from one or more offload engines.
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

drivers/mailbox/Kconfig

@@ -123,4 +123,13 @@ config XGENE_SLIMPRO_MBOX
 	  It is used to send short messages between ARM64-bit cores and
 	  the SLIMpro Management Engine, primarily for PM. Say Y here if you
 	  want to use the APM X-Gene SLIMpro IPCM support.
+
+config BCM_PDC_MBOX
+	tristate "Broadcom PDC Mailbox"
+	depends on ARM64 || COMPILE_TEST
+	default ARCH_BCM_IPROC
+	help
+	  Mailbox implementation for the Broadcom PDC ring manager,
+	  which provides access to various offload engines on Broadcom
+	  SoCs. Say Y here if you want to use the Broadcom PDC.
 endif

drivers/mailbox/Makefile

@@ -25,3 +25,5 @@ obj-$(CONFIG_TI_MESSAGE_MANAGER) += ti-msgmgr.o
 obj-$(CONFIG_XGENE_SLIMPRO_MBOX) += mailbox-xgene-slimpro.o
 
 obj-$(CONFIG_HI6220_MBOX)	+= hi6220-mailbox.o
+
+obj-$(CONFIG_BCM_PDC_MBOX)	+= bcm-pdc-mailbox.o

include/linux/mailbox/brcm-message.h

+/*
+ *  Copyright (C) 2016 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Common header for Broadcom mailbox messages which is shared across
+ * Broadcom SoCs and Broadcom mailbox client drivers.
+ */
+
+#ifndef _LINUX_BRCM_MESSAGE_H_
+#define _LINUX_BRCM_MESSAGE_H_
+
+#include <linux/scatterlist.h>
+
+enum brcm_message_type {
+	BRCM_MESSAGE_UNKNOWN = 0,
+	BRCM_MESSAGE_SPU,
+	BRCM_MESSAGE_SBA,
+	BRCM_MESSAGE_MAX,
+};
+
+struct brcm_sba_command {
+	u64 cmd;
+#define BRCM_SBA_CMD_TYPE_A		BIT(0)
+#define BRCM_SBA_CMD_TYPE_B		BIT(1)
+#define BRCM_SBA_CMD_TYPE_C		BIT(2)
+#define BRCM_SBA_CMD_HAS_RESP		BIT(3)
+#define BRCM_SBA_CMD_HAS_OUTPUT		BIT(4)
+	u64 flags;
+	dma_addr_t input;
+	size_t input_len;
+	dma_addr_t resp;
+	size_t resp_len;
+	dma_addr_t output;
+	size_t output_len;
+};
+
+struct brcm_message {
+	enum brcm_message_type type;
+	union {
+		struct {
+			struct scatterlist *src;
+			struct scatterlist *dst;
+		} spu;
+		struct {
+			struct brcm_sba_command *cmds;
+			unsigned int cmds_count;
+		} sba;
+	};
+	void *ctx;
+	int error;
+};
+
+#endif /* _LINUX_BRCM_MESSAGE_H_ */