mailbox: Add driver for Broadcom FlexRM ring manager

Some of the Broadcom iProc SoCs have FlexRM ring manager
which provides a ring-based programming interface to various
offload engines (e.g. RAID, Crypto, etc).

This patch adds a common mailbox driver for Broadcom FlexRM
ring manager which can be shared by various offload engine
drivers (implemented as mailbox clients).
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Pramod KUMAR <pramod.kumar@broadcom.com>
Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

drivers/mailbox/Kconfig

@@ -151,4 +151,15 @@ config BCM_PDC_MBOX
 	  Mailbox implementation for the Broadcom FlexSparx DMA ring manager,
 	  which provides access to various offload engines on Broadcom
 	  SoCs, including FA2/FA+ on Northstar Plus and PDC on Northstar 2.
+
+config BCM_FLEXRM_MBOX
+	tristate "Broadcom FlexRM Mailbox"
+	depends on ARM64 || COMPILE_TEST
+	depends on HAS_DMA
+	select GENERIC_MSI_IRQ_DOMAIN
+	default ARCH_BCM_IPROC
+	help
+	  Mailbox implementation of the Broadcom FlexRM ring manager,
+	  which provides access to various offload engines on Broadcom
+	  SoCs. Say Y here if you want to use the Broadcom FlexRM.
 endif

drivers/mailbox/Makefile

@@ -30,4 +30,6 @@ obj-$(CONFIG_HI6220_MBOX)	+= hi6220-mailbox.o
 
 obj-$(CONFIG_BCM_PDC_MBOX)	+= bcm-pdc-mailbox.o
 
+obj-$(CONFIG_BCM_FLEXRM_MBOX)	+= bcm-flexrm-mailbox.o
+
 obj-$(CONFIG_TEGRA_HSP_MBOX)	+= tegra-hsp.o

include/linux/mailbox/brcm-message.h

@@ -16,6 +16,7 @@
 
 enum brcm_message_type {
 	BRCM_MESSAGE_UNKNOWN = 0,
+	BRCM_MESSAGE_BATCH,
 	BRCM_MESSAGE_SPU,
 	BRCM_MESSAGE_SBA,
 	BRCM_MESSAGE_MAX,
@@ -23,23 +24,28 @@ enum brcm_message_type {
 
 struct brcm_sba_command {
 	u64 cmd;
+	u64 *cmd_dma;
+	dma_addr_t cmd_dma_addr;
 #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;
+	dma_addr_t data;
+	size_t data_len;
 };
 
 struct brcm_message {
 	enum brcm_message_type type;
 	union {
+		struct {
+			struct brcm_message *msgs;
+			unsigned int msgs_queued;
+			unsigned int msgs_count;
+		} batch;
 		struct {
 			struct scatterlist *src;
 			struct scatterlist *dst;