firmware: tegra: Add BPMP support

The Boot and Power Management Processor (BPMP) is a co-processor found
on Tegra SoCs. It is designed to handle the early stages of the boot
process and offload power management tasks (such as clocks, resets,
powergates, ...) as well as system control services.

Compared to the ARM SCPI, the services provided by BPMP are message-
based rather than method-based. The BPMP firmware driver provides the
services to transmit data to and receive data from the BPMP. Users can
also register a Message ReQuest (MRQ), for which a service routine will
be run when a corresponding event is received from the firmware.

A set of messages, called the BPMP ABI, are specified for a number of
different services provided by the BPMP (such as clocks or resets).

Based on work by Sivaram Nair <sivaramn@nvidia.com> and Joseph Lo
<josephl@nvidia.com>.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/firmware/tegra/Kconfig

@@ -10,4 +10,16 @@ config TEGRA_IVC
 	  keeps the content is synchronization between host CPU and remote
 	  processors.
 
+config TEGRA_BPMP
+	bool "Tegra BPMP driver"
+	depends on ARCH_TEGRA && TEGRA_HSP_MBOX && TEGRA_IVC
+	help
+	  BPMP (Boot and Power Management Processor) is designed to off-loading
+	  the PM functions which include clock/DVFS/thermal/power from the CPU.
+	  It needs HSP as the HW synchronization and notification module and
+	  IVC module as the message communication protocol.
+
+	  This driver manages the IPC interface between host CPU and the
+	  firmware running on BPMP.
+
 endmenu

drivers/firmware/tegra/Makefile

+obj-$(CONFIG_TEGRA_BPMP)	+= bpmp.o
 obj-$(CONFIG_TEGRA_IVC)		+= ivc.o

include/soc/tegra/bpmp.h

+/*
+ * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef __SOC_TEGRA_BPMP_H
+#define __SOC_TEGRA_BPMP_H
+
+#include <linux/mailbox_client.h>
+#include <linux/reset-controller.h>
+#include <linux/semaphore.h>
+#include <linux/types.h>
+
+#include <soc/tegra/bpmp-abi.h>
+
+struct tegra_bpmp_clk;
+
+struct tegra_bpmp_soc {
+	struct {
+		struct {
+			unsigned int offset;
+			unsigned int count;
+			unsigned int timeout;
+		} cpu_tx, thread, cpu_rx;
+	} channels;
+	unsigned int num_resets;
+};
+
+struct tegra_bpmp_mb_data {
+	u32 code;
+	u32 flags;
+	u8 data[MSG_DATA_MIN_SZ];
+} __packed;
+
+struct tegra_bpmp_channel {
+	struct tegra_bpmp *bpmp;
+	struct tegra_bpmp_mb_data *ib;
+	struct tegra_bpmp_mb_data *ob;
+	struct completion completion;
+	struct tegra_ivc *ivc;
+};
+
+typedef void (*tegra_bpmp_mrq_handler_t)(unsigned int mrq,
+					 struct tegra_bpmp_channel *channel,
+					 void *data);
+
+struct tegra_bpmp_mrq {
+	struct list_head list;
+	unsigned int mrq;
+	tegra_bpmp_mrq_handler_t handler;
+	void *data;
+};
+
+struct tegra_bpmp {
+	const struct tegra_bpmp_soc *soc;
+	struct device *dev;
+
+	struct {
+		struct gen_pool *pool;
+		dma_addr_t phys;
+		void *virt;
+	} tx, rx;
+
+	struct {
+		struct mbox_client client;
+		struct mbox_chan *channel;
+	} mbox;
+
+	struct tegra_bpmp_channel *channels;
+	unsigned int num_channels;
+
+	struct {
+		unsigned long *allocated;
+		unsigned long *busy;
+		unsigned int count;
+		struct semaphore lock;
+	} threaded;
+
+	struct list_head mrqs;
+	spinlock_t lock;
+
+	struct tegra_bpmp_clk **clocks;
+	unsigned int num_clocks;
+
+	struct reset_controller_dev rstc;
+};
+
+struct tegra_bpmp *tegra_bpmp_get(struct device *dev);
+void tegra_bpmp_put(struct tegra_bpmp *bpmp);
+
+struct tegra_bpmp_message {
+	unsigned int mrq;
+
+	struct {
+		const void *data;
+		size_t size;
+	} tx;
+
+	struct {
+		void *data;
+		size_t size;
+	} rx;
+};
+
+int tegra_bpmp_transfer_atomic(struct tegra_bpmp *bpmp,
+			       struct tegra_bpmp_message *msg);
+int tegra_bpmp_transfer(struct tegra_bpmp *bpmp,
+			struct tegra_bpmp_message *msg);
+
+int tegra_bpmp_request_mrq(struct tegra_bpmp *bpmp, unsigned int mrq,
+			   tegra_bpmp_mrq_handler_t handler, void *data);
+void tegra_bpmp_free_mrq(struct tegra_bpmp *bpmp, unsigned int mrq,
+			 void *data);
+
+#if IS_ENABLED(CONFIG_CLK_TEGRA_BPMP)
+int tegra_bpmp_init_clocks(struct tegra_bpmp *bpmp);
+#else
+static inline int tegra_bpmp_init_clocks(struct tegra_bpmp *bpmp)
+{
+	return 0;
+}
+#endif
+
+#if IS_ENABLED(CONFIG_RESET_TEGRA_BPMP)
+int tegra_bpmp_init_resets(struct tegra_bpmp *bpmp);
+#else
+static inline int tegra_bpmp_init_resets(struct tegra_bpmp *bpmp)
+{
+	return 0;
+}
+#endif
+
+#endif /* __SOC_TEGRA_BPMP_H */