soc: qcom: hab: add the guest_shm.h header file

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/**

 * @file

 * definitions guest shared memory device

 */

#ifndef _QVM_GUEST_SHM_H

#define _QVM_GUEST_SHM_H

#ifdef __linux__

#include <linux/types.h>

#else

#include <stdint.h>

#endif

/*

 * Temporary VID definition until the updated <pci/pci_id.h> propogates around

 */

#define PCI_VID_BlackBerry_QNX	0x1C05

#define PCI_DID_QNX_GUEST_SHM	0x0001

/** status of last creation request */

enum guest_shm_status {

	GSS_OK,					/**< creation succeeded */

	GSS_UNKNOWN_FAILURE,	/**< creation failed for an unknown reason */

	GSS_NOMEM,				/**< creation failed due to lack of memory */

	GSS_CLIENT_MAX,			/**< creation failed due to region already being used by the maximum number of guests */

	GSS_ILLEGAL_NAME,		/**< creation failed due to illegal region name */

	GSS_NO_PERMISSION,		/**< creation failed due to lack of permission */

	GSS_DOES_NOT_EXIST,		/**< A find request failed */

};

/** Maximum number of clients allowed to connect to a shared memory region */

#define GUEST_SHM_MAX_CLIENTS	16

/** Maximum length allowed for region name */

#define GUEST_SHM_MAX_NAME	32

/** Signature value to verify that vdev is present */

#define GUEST_SHM_SIGNATURE 0x4d534732474d5651

/** Register layout for factory registers */

struct guest_shm_factory {

	uint64_t		signature; /**< == GUEST_SHM_SIGNATURE (R/O) */

	uint64_t		shmem;	/**< shared memory paddr (R/O) */

	uint32_t		vector;	/**< interrupt vector number (R/O) */

	uint32_t		status; /**< status of last creation (R/O) */

	uint32_t		size;	/**< requested size in 4K pages, write causes creation */

	char			name[GUEST_SHM_MAX_NAME];	/**< name of shared memory region */

	uint32_t		find;	/**< find an existing shared memory connection */

};

/** Register layout for a region control page */

struct guest_shm_control {

	uint32_t		status;	/**< lower 16 bits: pending notification bitset, upper 16 bits: current active clients (R/O) */

	uint32_t		idx;	/**< connection index for this client (R/O) */

	uint32_t		notify;	/**< write a bitset of clients to notify */

	uint32_t		detach; /**< write here to detach from the shared memory region */

};

static inline void

guest_shm_create(volatile struct guest_shm_factory *const __factory, unsigned const __size) {

	/* Surround the size assignment with memory barriers so that

	 * the compiler doesn't try to shift the assignment before/after

	 * necessary bits (e.g. setting the name of the region) */

	asm volatile( "" ::: "memory");

	__factory->size = __size;

	asm volatile( "" ::: "memory");

}

static inline void

guest_shm_find(volatile struct guest_shm_factory *const __factory, unsigned const __find_num) {

	/* Surround the find assignment with memory barriers so that

	 * the compiler doesn't try to shift the assignment before/after

	 * necessary bits (e.g. setting the name of the region) */

	asm volatile( "" ::: "memory");

	__factory->find = __find_num;

	asm volatile( "" ::: "memory");

}

#endif

#if defined(__QNXNTO__) && defined(__USESRCVERSION)

#include <sys/srcversion.h>

__SRCVERSION("$URL$ $Rev$")

#endif