[mirror_edk2.git] / OvmfPkg / Include / Library / VirtioLib.h

/** @file\r
\r
  Declarations of utility functions used by virtio device drivers.\r
\r
  Copyright (C) 2012, Red Hat, Inc.\r
\r
  This program and the accompanying materials are licensed and made available\r
  under the terms and conditions of the BSD License which accompanies this\r
  distribution. The full text of the license may be found at\r
  http://opensource.org/licenses/bsd-license.php\r
\r
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT\r
  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
**/\r
\r
#ifndef _VIRTIO_LIB_H_\r
#define _VIRTIO_LIB_H_\r
\r
#include <Protocol/PciIo.h>\r
#include <IndustryStandard/Virtio.h>\r
\r
/**\r
\r
  Write a word into Region 0 of the device specified by PciIo.\r
\r
  Region 0 must be an iomem region. This is an internal function for the\r
  driver-specific VIRTIO_CFG_WRITE() macros.\r
\r
  @param[in] PciIo        Target PCI device.\r
\r
  @param[in] FieldOffset  Destination offset.\r
\r
  @param[in] FieldSize    Destination field size, must be in { 1, 2, 4, 8 }.\r
\r
  @param[in] Value        Little endian value to write, converted to UINT64.\r
                          The least significant FieldSize bytes will be used.\r
\r
\r
  @return  Status code returned by PciIo->Io.Write().\r
\r
**/\r
EFIAPI\r
EFI_STATUS\r
VirtioWrite (\r
  IN EFI_PCI_IO_PROTOCOL *PciIo,\r
  IN UINTN               FieldOffset,\r
  IN UINTN               FieldSize,\r
  IN UINT64              Value\r
  );\r
\r
\r
/**\r
\r
  Read a word from Region 0 of the device specified by PciIo.\r
\r
  Region 0 must be an iomem region. This is an internal function for the\r
  driver-specific VIRTIO_CFG_READ() macros.\r
\r
  @param[in] PciIo        Source PCI device.\r
\r
  @param[in] FieldOffset  Source offset.\r
\r
  @param[in] FieldSize    Source field size, must be in { 1, 2, 4, 8 }.\r
\r
  @param[in] BufferSize   Number of bytes available in the target buffer. Must\r
                          equal FieldSize.\r
\r
  @param[out] Buffer      Target buffer.\r
\r
\r
  @return  Status code returned by PciIo->Io.Read().\r
\r
**/\r
EFIAPI\r
EFI_STATUS\r
VirtioRead (\r
  IN  EFI_PCI_IO_PROTOCOL *PciIo,\r
  IN  UINTN               FieldOffset,\r
  IN  UINTN               FieldSize,\r
  IN  UINTN               BufferSize,\r
  OUT VOID                *Buffer\r
  );\r
\r
\r
/**\r
\r
  Configure a virtio ring.\r
\r
  This function sets up internal storage (the guest-host communication area)\r
  and lays out several "navigation" (ie. no-ownership) pointers to parts of\r
  that storage.\r
\r
  Relevant sections from the virtio-0.9.5 spec:\r
  - 1.1 Virtqueues,\r
  - 2.3 Virtqueue Configuration.\r
\r
  @param[in]                    The number of descriptors to allocate for the\r
                                virtio ring, as requested by the host.\r
\r
  @param[out] Ring              The virtio ring to set up.\r
\r
  @retval EFI_OUT_OF_RESOURCES  AllocatePages() failed to allocate contiguous\r
                                pages for the requested QueueSize. Fields of\r
                                Ring have indeterminate value.\r
\r
  @retval EFI_SUCCESS           Allocation and setup successful. Ring->Base\r
                                (and nothing else) is responsible for\r
                                deallocation.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
VirtioRingInit (\r
  IN  UINT16 QueueSize,\r
  OUT VRING  *Ring\r
  );\r
\r
\r
/**\r
\r
  Tear down the internal resources of a configured virtio ring.\r
\r
  The caller is responsible to stop the host from using this ring before\r
  invoking this function: the VSTAT_DRIVER_OK bit must be clear in\r
  VhdrDeviceStatus.\r
\r
  @param[out] Ring  The virtio ring to clean up.\r
\r
**/\r
VOID\r
EFIAPI\r
VirtioRingUninit (\r
  IN OUT VRING *Ring\r
  );\r
\r
\r
/**\r
\r
  Append a contiguous buffer for transmission / reception via the virtio ring.\r
\r
  This function implements the following sections from virtio-0.9.5:\r
  - 2.4.1.1 Placing Buffers into the Descriptor Table\r
  - 2.4.1.2 Updating the Available Ring\r
\r
  Free space is taken as granted, since the individual drivers support only\r
  synchronous requests and host side status is processed in lock-step with\r
  request submission. It is the calling driver's responsibility to verify the\r
  ring size in advance.\r
\r
  @param[in out] Ring           The virtio ring to append the buffer to, as a\r
                                descriptor.\r
\r
  @param [in] BufferPhysAddr    (Guest pseudo-physical) start address of the\r
                                transmit / receive buffer.\r
\r
  @param [in] BufferSize        Number of bytes to transmit or receive.\r
\r
  @param [in] Flags             A bitmask of VRING_DESC_F_* flags. The caller\r
                                computes this mask dependent on further buffers\r
                                to append and transfer direction.\r
                                VRING_DESC_F_INDIRECT is unsupported. The\r
                                VRING_DESC.Next field is always set, but the\r
                                host only interprets it dependent on\r
                                VRING_DESC_F_NEXT.\r
\r
  @param [in] HeadIdx           The index identifying the head buffer (first\r
                                buffer appended) belonging to this same\r
                                request.\r
\r
  @param [in out] NextAvailIdx  On input, the index identifying the next\r
                                descriptor available to carry the buffer. On\r
                                output, incremented by one, modulo 2^16.\r
\r
**/\r
VOID\r
EFIAPI\r
VirtioAppendDesc (\r
  IN OUT VRING  *Ring,\r
  IN     UINTN  BufferPhysAddr,\r
  IN     UINT32 BufferSize,\r
  IN     UINT16 Flags,\r
  IN     UINT16 HeadIdx,\r
  IN OUT UINT16 *NextAvailIdx\r
  );\r
\r
#endif // _VIRTIO_LIB_H_\r
Commit	Line	Data
263559b8	1	/** @file\r
	2	\r
	3	Declarations of utility functions used by virtio device drivers.\r
	4	\r
	5	Copyright (C) 2012, Red Hat, Inc.\r
	6	\r
	7	This program and the accompanying materials are licensed and made available\r
	8	under the terms and conditions of the BSD License which accompanies this\r
	9	distribution. The full text of the license may be found at\r
	10	http://opensource.org/licenses/bsd-license.php\r
	11	\r
	12	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT\r
	13	WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	14	\r
	15	**/\r
	16	\r
	17	#ifndef _VIRTIO_LIB_H_\r
	18	#define _VIRTIO_LIB_H_\r
	19	\r
	20	#include <Protocol/PciIo.h>\r
	21	#include <IndustryStandard/Virtio.h>\r
	22	\r
	23	/**\r
	24	\r
	25	Write a word into Region 0 of the device specified by PciIo.\r
	26	\r
	27	Region 0 must be an iomem region. This is an internal function for the\r
	28	driver-specific VIRTIO_CFG_WRITE() macros.\r
	29	\r
	30	@param[in] PciIo Target PCI device.\r
	31	\r
	32	@param[in] FieldOffset Destination offset.\r
	33	\r
	34	@param[in] FieldSize Destination field size, must be in { 1, 2, 4, 8 }.\r
	35	\r
	36	@param[in] Value Little endian value to write, converted to UINT64.\r
	37	The least significant FieldSize bytes will be used.\r
	38	\r
	39	\r
	40	@return Status code returned by PciIo->Io.Write().\r
	41	\r
	42	**/\r
	43	EFIAPI\r
	44	EFI_STATUS\r
	45	VirtioWrite (\r
	46	IN EFI_PCI_IO_PROTOCOL *PciIo,\r
	47	IN UINTN FieldOffset,\r
	48	IN UINTN FieldSize,\r
	49	IN UINT64 Value\r
	50	);\r
	51	\r
	52	\r
	53	/**\r
	54	\r
	55	Read a word from Region 0 of the device specified by PciIo.\r
	56	\r
	57	Region 0 must be an iomem region. This is an internal function for the\r
	58	driver-specific VIRTIO_CFG_READ() macros.\r
	59	\r
	60	@param[in] PciIo Source PCI device.\r
	61	\r
	62	@param[in] FieldOffset Source offset.\r
	63	\r
	64	@param[in] FieldSize Source field size, must be in { 1, 2, 4, 8 }.\r
65	\r
66	@param[in] BufferSize Number of bytes available in the target buffer. Must\r
67	equal FieldSize.\r
68	\r
69	@param[out] Buffer Target buffer.\r
70	\r
71	\r
72	@return Status code returned by PciIo->Io.Read().\r
73	\r
74	**/\r
75	EFIAPI\r
76	EFI_STATUS\r
77	VirtioRead (\r
78	IN EFI_PCI_IO_PROTOCOL *PciIo,\r
79	IN UINTN FieldOffset,\r
80	IN UINTN FieldSize,\r
81	IN UINTN BufferSize,\r
82	OUT VOID *Buffer\r
83	);\r
84	\r
85	\r
86	/**\r
87	\r
88	Configure a virtio ring.\r
89	\r
90	This function sets up internal storage (the guest-host communication area)\r
91	and lays out several "navigation" (ie. no-ownership) pointers to parts of\r
92	that storage.\r
93	\r
94	Relevant sections from the virtio-0.9.5 spec:\r
95	- 1.1 Virtqueues,\r
96	- 2.3 Virtqueue Configuration.\r
97	\r
98	@param[in] The number of descriptors to allocate for the\r
99	virtio ring, as requested by the host.\r
100	\r
101	@param[out] Ring The virtio ring to set up.\r
102	\r
103	@retval EFI_OUT_OF_RESOURCES AllocatePages() failed to allocate contiguous\r
104	pages for the requested QueueSize. Fields of\r
105	Ring have indeterminate value.\r
106	\r
107	@retval EFI_SUCCESS Allocation and setup successful. Ring->Base\r
108	(and nothing else) is responsible for\r
109	deallocation.\r
110	\r
111	**/\r
112	EFI_STATUS\r
113	EFIAPI\r
114	VirtioRingInit (\r
115	IN UINT16 QueueSize,\r
116	OUT VRING *Ring\r
117	);\r
118	\r
119	\r
120	/**\r
121	\r
122	Tear down the internal resources of a configured virtio ring.\r
123	\r
124	The caller is responsible to stop the host from using this ring before\r
125	invoking this function: the VSTAT_DRIVER_OK bit must be clear in\r
126	VhdrDeviceStatus.\r
127	\r
128	@param[out] Ring The virtio ring to clean up.\r
129	\r
130	**/\r
131	VOID\r
132	EFIAPI\r
133	VirtioRingUninit (\r
134	IN OUT VRING *Ring\r
135	);\r
136	\r
137	\r
138	/**\r
139	\r
140	Append a contiguous buffer for transmission / reception via the virtio ring.\r
141	\r
142	This function implements the following sections from virtio-0.9.5:\r
143	- 2.4.1.1 Placing Buffers into the Descriptor Table\r
144	- 2.4.1.2 Updating the Available Ring\r
145	\r
146	Free space is taken as granted, since the individual drivers support only\r
147	synchronous requests and host side status is processed in lock-step with\r
148	request submission. It is the calling driver's responsibility to verify the\r
149	ring size in advance.\r
150	\r
151	@param[in out] Ring The virtio ring to append the buffer to, as a\r
152	descriptor.\r
153	\r
154	@param [in] BufferPhysAddr (Guest pseudo-physical) start address of the\r
155	transmit / receive buffer.\r
156	\r
157	@param [in] BufferSize Number of bytes to transmit or receive.\r
158	\r
159	@param [in] Flags A bitmask of VRING_DESC_F_* flags. The caller\r
160	computes this mask dependent on further buffers\r
161	to append and transfer direction.\r
162	VRING_DESC_F_INDIRECT is unsupported. The\r
163	VRING_DESC.Next field is always set, but the\r
164	host only interprets it dependent on\r
165	VRING_DESC_F_NEXT.\r
166	\r
167	@param [in] HeadIdx The index identifying the head buffer (first\r
168	buffer appended) belonging to this same\r
169	request.\r
170	\r
171	@param [in out] NextAvailIdx On input, the index identifying the next\r
172	descriptor available to carry the buffer. On\r
173	output, incremented by one, modulo 2^16.\r
174	\r
175	**/\r
176	VOID\r
177	EFIAPI\r
7fcacd6c	178	VirtioAppendDesc (\r
263559b8	179	IN OUT VRING *Ring,\r
	180	IN UINTN BufferPhysAddr,\r
	181	IN UINT32 BufferSize,\r
	182	IN UINT16 Flags,\r
	183	IN UINT16 HeadIdx,\r
	184	IN OUT UINT16 *NextAvailIdx\r
	185	);\r
	186	\r
	187	#endif // _VIRTIO_LIB_H_\r