Merge tag 'arm-ffa-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/drivers

Arm Firmware Framework for ARMv8-A(FFA) interface driver

The Arm FFA specification describes a software architecture to
leverages the virtualization extension to isolate software images
provided by an ecosystem of vendors from each other and describes
interfaces that standardize communication between the various software
images including communication between images in the Secure world and
Normal world. Any Hypervisor could use the FFA interfaces to enable
communication between VMs it manages.

The Hypervisor a.k.a Partition managers in FFA terminology can assign
system resources(Memory regions, Devices, CPU cycles) to the partitions
and manage isolation amongst them.

This is the initial and minimal support for the FFA interface to enable
communication between secure partitions and the normal world OS.

* tag 'arm-ffa-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
  firmware: arm_ffa: Add support for MEM_* interfaces
  firmware: arm_ffa: Setup in-kernel users of FFA partitions
  firmware: arm_ffa: Add support for SMCCC as transport to FFA driver
  firmware: arm_ffa: Add initial Arm FFA driver support
  firmware: arm_ffa: Add initial FFA bus support for device enumeration
  arm64: smccc: Add support for SMCCCv1.2 extended input/output registers

Link: https://lore.kernel.org/r/20210601095838.GA838783@bogus
Signed-off-by: Olof Johansson <olof@lixom.net>

2 files changed, 322 insertions, 0 deletions

diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 6861489a1890..5cef2b8b0479 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -227,6 +227,61 @@ struct arm_smccc_res {
 	unsigned long a3;
 };
 
+#ifdef CONFIG_ARM64
+/**
+ * struct arm_smccc_1_2_regs - Arguments for or Results from SMC/HVC call
+ * @a0-a17 argument values from registers 0 to 17
+ */
+struct arm_smccc_1_2_regs {
+	unsigned long a0;
+	unsigned long a1;
+	unsigned long a2;
+	unsigned long a3;
+	unsigned long a4;
+	unsigned long a5;
+	unsigned long a6;
+	unsigned long a7;
+	unsigned long a8;
+	unsigned long a9;
+	unsigned long a10;
+	unsigned long a11;
+	unsigned long a12;
+	unsigned long a13;
+	unsigned long a14;
+	unsigned long a15;
+	unsigned long a16;
+	unsigned long a17;
+};
+
+/**
+ * arm_smccc_1_2_hvc() - make HVC calls
+ * @args: arguments passed via struct arm_smccc_1_2_regs
+ * @res: result values via struct arm_smccc_1_2_regs
+ *
+ * This function is used to make HVC calls following SMC Calling Convention
+ * v1.2 or above. The content of the supplied param are copied from the
+ * structure to registers prior to the HVC instruction. The return values
+ * are updated with the content from registers on return from the HVC
+ * instruction.
+ */
+asmlinkage void arm_smccc_1_2_hvc(const struct arm_smccc_1_2_regs *args,
+				  struct arm_smccc_1_2_regs *res);
+
+/**
+ * arm_smccc_1_2_smc() - make SMC calls
+ * @args: arguments passed via struct arm_smccc_1_2_regs
+ * @res: result values via struct arm_smccc_1_2_regs
+ *
+ * This function is used to make SMC calls following SMC Calling Convention
+ * v1.2 or above. The content of the supplied param are copied from the
+ * structure to registers prior to the SMC instruction. The return values
+ * are updated with the content from registers on return from the SMC
+ * instruction.
+ */
+asmlinkage void arm_smccc_1_2_smc(const struct arm_smccc_1_2_regs *args,
+				  struct arm_smccc_1_2_regs *res);
+#endif
+
 /**
  * struct arm_smccc_quirk - Contains quirk information
  * @id: quirk identification
diff --git a/include/linux/arm_ffa.h b/include/linux/arm_ffa.h
new file mode 100644
index 000000000000..505c679b6a9b
--- /dev/null
+++ b/include/linux/arm_ffa.h
@@ -0,0 +1,267 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 ARM Ltd.
+ */
+
+#ifndef _LINUX_ARM_FFA_H
+#define _LINUX_ARM_FFA_H
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/uuid.h>
+
+/* FFA Bus/Device/Driver related */
+struct ffa_device {
+	int vm_id;
+	bool mode_32bit;
+	uuid_t uuid;
+	struct device dev;
+};
+
+#define to_ffa_dev(d) container_of(d, struct ffa_device, dev)
+
+struct ffa_device_id {
+	uuid_t uuid;
+};
+
+struct ffa_driver {
+	const char *name;
+	int (*probe)(struct ffa_device *sdev);
+	void (*remove)(struct ffa_device *sdev);
+	const struct ffa_device_id *id_table;
+
+	struct device_driver driver;
+};
+
+#define to_ffa_driver(d) container_of(d, struct ffa_driver, driver)
+
+static inline void ffa_dev_set_drvdata(struct ffa_device *fdev, void *data)
+{
+	fdev->dev.driver_data = data;
+}
+
+#if IS_REACHABLE(CONFIG_ARM_FFA_TRANSPORT)
+struct ffa_device *ffa_device_register(const uuid_t *uuid, int vm_id);
+void ffa_device_unregister(struct ffa_device *ffa_dev);
+int ffa_driver_register(struct ffa_driver *driver, struct module *owner,
+			const char *mod_name);
+void ffa_driver_unregister(struct ffa_driver *driver);
+bool ffa_device_is_valid(struct ffa_device *ffa_dev);
+const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev);
+
+#else
+static inline
+struct ffa_device *ffa_device_register(const uuid_t *uuid, int vm_id)
+{
+	return NULL;
+}
+
+static inline void ffa_device_unregister(struct ffa_device *dev) {}
+
+static inline int
+ffa_driver_register(struct ffa_driver *driver, struct module *owner,
+		    const char *mod_name)
+{
+	return -EINVAL;
+}
+
+static inline void ffa_driver_unregister(struct ffa_driver *driver) {}
+
+static inline
+bool ffa_device_is_valid(struct ffa_device *ffa_dev) { return false; }
+
+static inline
+const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev)
+{
+	return NULL;
+}
+#endif /* CONFIG_ARM_FFA_TRANSPORT */
+
+#define ffa_register(driver) \
+	ffa_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
+#define ffa_unregister(driver) \
+	ffa_driver_unregister(driver)
+
+/**
+ * module_ffa_driver() - Helper macro for registering a psa_ffa driver
+ * @__ffa_driver: ffa_driver structure
+ *
+ * Helper macro for psa_ffa drivers to set up proper module init / exit
+ * functions.  Replaces module_init() and module_exit() and keeps people from
+ * printing pointless things to the kernel log when their driver is loaded.
+ */
+#define module_ffa_driver(__ffa_driver)	\
+	module_driver(__ffa_driver, ffa_register, ffa_unregister)
+
+/* FFA transport related */
+struct ffa_partition_info {
+	u16 id;
+	u16 exec_ctxt;
+/* partition supports receipt of direct requests */
+#define FFA_PARTITION_DIRECT_RECV	BIT(0)
+/* partition can send direct requests. */
+#define FFA_PARTITION_DIRECT_SEND	BIT(1)
+/* partition can send and receive indirect messages. */
+#define FFA_PARTITION_INDIRECT_MSG	BIT(2)
+	u32 properties;
+};
+
+/* For use with FFA_MSG_SEND_DIRECT_{REQ,RESP} which pass data via registers */
+struct ffa_send_direct_data {
+	unsigned long data0; /* w3/x3 */
+	unsigned long data1; /* w4/x4 */
+	unsigned long data2; /* w5/x5 */
+	unsigned long data3; /* w6/x6 */
+	unsigned long data4; /* w7/x7 */
+};
+
+struct ffa_mem_region_addr_range {
+	/* The base IPA of the constituent memory region, aligned to 4 kiB */
+	u64 address;
+	/* The number of 4 kiB pages in the constituent memory region. */
+	u32 pg_cnt;
+	u32 reserved;
+};
+
+struct ffa_composite_mem_region {
+	/*
+	 * The total number of 4 kiB pages included in this memory region. This
+	 * must be equal to the sum of page counts specified in each
+	 * `struct ffa_mem_region_addr_range`.
+	 */
+	u32 total_pg_cnt;
+	/* The number of constituents included in this memory region range */
+	u32 addr_range_cnt;
+	u64 reserved;
+	/** An array of `addr_range_cnt` memory region constituents. */
+	struct ffa_mem_region_addr_range constituents[];
+};
+
+struct ffa_mem_region_attributes {
+	/* The ID of the VM to which the memory is being given or shared. */
+	u16 receiver;
+	/*
+	 * The permissions with which the memory region should be mapped in the
+	 * receiver's page table.
+	 */
+#define FFA_MEM_EXEC		BIT(3)
+#define FFA_MEM_NO_EXEC		BIT(2)
+#define FFA_MEM_RW		BIT(1)
+#define FFA_MEM_RO		BIT(0)
+	u8 attrs;
+	/*
+	 * Flags used during FFA_MEM_RETRIEVE_REQ and FFA_MEM_RETRIEVE_RESP
+	 * for memory regions with multiple borrowers.
+	 */
+#define FFA_MEM_RETRIEVE_SELF_BORROWER	BIT(0)
+	u8 flag;
+	u32 composite_off;
+	/*
+	 * Offset in bytes from the start of the outer `ffa_memory_region` to
+	 * an `struct ffa_mem_region_addr_range`.
+	 */
+	u64 reserved;
+};
+
+struct ffa_mem_region {
+	/* The ID of the VM/owner which originally sent the memory region */
+	u16 sender_id;
+#define FFA_MEM_NORMAL		BIT(5)
+#define FFA_MEM_DEVICE		BIT(4)
+
+#define FFA_MEM_WRITE_BACK	(3 << 2)
+#define FFA_MEM_NON_CACHEABLE	(1 << 2)
+
+#define FFA_DEV_nGnRnE		(0 << 2)
+#define FFA_DEV_nGnRE		(1 << 2)
+#define FFA_DEV_nGRE		(2 << 2)
+#define FFA_DEV_GRE		(3 << 2)
+
+#define FFA_MEM_NON_SHAREABLE	(0)
+#define FFA_MEM_OUTER_SHAREABLE	(2)
+#define FFA_MEM_INNER_SHAREABLE	(3)
+	u8 attributes;
+	u8 reserved_0;
+/*
+ * Clear memory region contents after unmapping it from the sender and
+ * before mapping it for any receiver.
+ */
+#define FFA_MEM_CLEAR			BIT(0)
+/*
+ * Whether the hypervisor may time slice the memory sharing or retrieval
+ * operation.
+ */
+#define FFA_TIME_SLICE_ENABLE		BIT(1)
+
+#define FFA_MEM_RETRIEVE_TYPE_IN_RESP	(0 << 3)
+#define FFA_MEM_RETRIEVE_TYPE_SHARE	(1 << 3)
+#define FFA_MEM_RETRIEVE_TYPE_LEND	(2 << 3)
+#define FFA_MEM_RETRIEVE_TYPE_DONATE	(3 << 3)
+
+#define FFA_MEM_RETRIEVE_ADDR_ALIGN_HINT	BIT(9)
+#define FFA_MEM_RETRIEVE_ADDR_ALIGN(x)		((x) << 5)
+	/* Flags to control behaviour of the transaction. */
+	u32 flags;
+#define HANDLE_LOW_MASK		GENMASK_ULL(31, 0)
+#define HANDLE_HIGH_MASK	GENMASK_ULL(63, 32)
+#define HANDLE_LOW(x)		((u32)(FIELD_GET(HANDLE_LOW_MASK, (x))))
+#define	HANDLE_HIGH(x)		((u32)(FIELD_GET(HANDLE_HIGH_MASK, (x))))
+
+#define PACK_HANDLE(l, h)		\
+	(FIELD_PREP(HANDLE_LOW_MASK, (l)) | FIELD_PREP(HANDLE_HIGH_MASK, (h)))
+	/*
+	 * A globally-unique ID assigned by the hypervisor for a region
+	 * of memory being sent between VMs.
+	 */
+	u64 handle;
+	/*
+	 * An implementation defined value associated with the receiver and the
+	 * memory region.
+	 */
+	u64 tag;
+	u32 reserved_1;
+	/*
+	 * The number of `ffa_mem_region_attributes` entries included in this
+	 * transaction.
+	 */
+	u32 ep_count;
+	/*
+	 * An array of endpoint memory access descriptors.
+	 * Each one specifies a memory region offset, an endpoint and the
+	 * attributes with which this memory region should be mapped in that
+	 * endpoint's page table.
+	 */
+	struct ffa_mem_region_attributes ep_mem_access[];
+};
+
+#define	COMPOSITE_OFFSET(x)	\
+	(offsetof(struct ffa_mem_region, ep_mem_access[x]))
+#define CONSTITUENTS_OFFSET(x)	\
+	(offsetof(struct ffa_composite_mem_region, constituents[x]))
+#define COMPOSITE_CONSTITUENTS_OFFSET(x, y)	\
+	(COMPOSITE_OFFSET(x) + CONSTITUENTS_OFFSET(y))
+
+struct ffa_mem_ops_args {
+	bool use_txbuf;
+	u32 nattrs;
+	u32 flags;
+	u64 tag;
+	u64 g_handle;
+	struct scatterlist *sg;
+	struct ffa_mem_region_attributes *attrs;
+};
+
+struct ffa_dev_ops {
+	u32 (*api_version_get)(void);
+	int (*partition_info_get)(const char *uuid_str,
+				  struct ffa_partition_info *buffer);
+	void (*mode_32bit_set)(struct ffa_device *dev);
+	int (*sync_send_receive)(struct ffa_device *dev,
+				 struct ffa_send_direct_data *data);
+	int (*memory_reclaim)(u64 g_handle, u32 flags);
+	int (*memory_share)(struct ffa_device *dev,
+			    struct ffa_mem_ops_args *args);
+};
+
+#endif /* _LINUX_ARM_FFA_H */