NTB: Add Messaging NTB API

Some IDT NTB-capable PCIe-switches have message registers to communicate with
peer devices. This patch adds new NTB API callback methods, which can be used
to utilize these registers functionality:
 ntb_msg_count(); - get number of message registers
 ntb_msg_inbits(); - get bitfield of inbound message registers status
 ntb_msg_outbits(); - get bitfield of outbound message registers status
 ntb_msg_read_sts(); - read the inbound and outbound message registers status
 ntb_msg_clear_sts(); - clear status bits of message registers
 ntb_msg_set_mask(); - mask interrupts raised by status bits of message
registers.
 ntb_msg_clear_mask(); - clear interrupts mask bits of message registers
 ntb_msg_read(midx, *pidx); - read message register with specified index,
additionally getting peer port index which data received from
 ntb_msg_write(midx, pidx); - write data to the specified message register
sending it to the passed peer device connected over a pidx port
 ntb_msg_event(); - notify driver context of a new message event

Of course there is hardware which doesn't support Message registers, so
this API is made optional.

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
This commit is contained in:
Serge Semin 2016-12-20 12:48:20 +03:00 committed by Jon Mason
parent d67288a395
commit bc3e49adc2
2 changed files with 218 additions and 0 deletions

View File

@ -193,6 +193,19 @@ void ntb_db_event(struct ntb_dev *ntb, int vector)
}
EXPORT_SYMBOL(ntb_db_event);
void ntb_msg_event(struct ntb_dev *ntb)
{
unsigned long irqflags;
spin_lock_irqsave(&ntb->ctx_lock, irqflags);
{
if (ntb->ctx_ops && ntb->ctx_ops->msg_event)
ntb->ctx_ops->msg_event(ntb->ctx);
}
spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
}
EXPORT_SYMBOL(ntb_msg_event);
int ntb_default_port_number(struct ntb_dev *ntb)
{
switch (ntb->topo) {

View File

@ -178,10 +178,12 @@ static inline int ntb_client_ops_is_valid(const struct ntb_client_ops *ops)
* struct ntb_ctx_ops - ntb driver context operations
* @link_event: See ntb_link_event().
* @db_event: See ntb_db_event().
* @msg_event: See ntb_msg_event().
*/
struct ntb_ctx_ops {
void (*link_event)(void *ctx);
void (*db_event)(void *ctx, int db_vector);
void (*msg_event)(void *ctx);
};
static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops)
@ -190,6 +192,7 @@ static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops)
return
/* ops->link_event && */
/* ops->db_event && */
/* ops->msg_event && */
1;
}
@ -234,6 +237,15 @@ static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops)
* @peer_spad_addr: See ntb_peer_spad_addr().
* @peer_spad_read: See ntb_peer_spad_read().
* @peer_spad_write: See ntb_peer_spad_write().
* @msg_count: See ntb_msg_count().
* @msg_inbits: See ntb_msg_inbits().
* @msg_outbits: See ntb_msg_outbits().
* @msg_read_sts: See ntb_msg_read_sts().
* @msg_clear_sts: See ntb_msg_clear_sts().
* @msg_set_mask: See ntb_msg_set_mask().
* @msg_clear_mask: See ntb_msg_clear_mask().
* @msg_read: See ntb_msg_read().
* @msg_write: See ntb_msg_write().
*/
struct ntb_dev_ops {
int (*port_number)(struct ntb_dev *ntb);
@ -296,6 +308,16 @@ struct ntb_dev_ops {
u32 (*peer_spad_read)(struct ntb_dev *ntb, int pidx, int sidx);
int (*peer_spad_write)(struct ntb_dev *ntb, int pidx, int sidx,
u32 val);
int (*msg_count)(struct ntb_dev *ntb);
u64 (*msg_inbits)(struct ntb_dev *ntb);
u64 (*msg_outbits)(struct ntb_dev *ntb);
u64 (*msg_read_sts)(struct ntb_dev *ntb);
int (*msg_clear_sts)(struct ntb_dev *ntb, u64 sts_bits);
int (*msg_set_mask)(struct ntb_dev *ntb, u64 mask_bits);
int (*msg_clear_mask)(struct ntb_dev *ntb, u64 mask_bits);
int (*msg_read)(struct ntb_dev *ntb, int midx, int *pidx, u32 *msg);
int (*msg_write)(struct ntb_dev *ntb, int midx, int pidx, u32 msg);
};
static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops)
@ -342,6 +364,15 @@ static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops)
/* !ops->peer_spad_addr == !ops->spad_count && */
/* !ops->peer_spad_read == !ops->spad_count && */
!ops->peer_spad_write == !ops->spad_count &&
!ops->msg_inbits == !ops->msg_count &&
!ops->msg_outbits == !ops->msg_count &&
!ops->msg_read_sts == !ops->msg_count &&
!ops->msg_clear_sts == !ops->msg_count &&
/* !ops->msg_set_mask == !ops->msg_count && */
/* !ops->msg_clear_mask == !ops->msg_count && */
!ops->msg_read == !ops->msg_count &&
!ops->msg_write == !ops->msg_count &&
1;
}
@ -484,6 +515,18 @@ void ntb_link_event(struct ntb_dev *ntb);
*/
void ntb_db_event(struct ntb_dev *ntb, int vector);
/**
* ntb_msg_event() - notify driver context of a message event
* @ntb: NTB device context.
*
* Notify the driver context of a message event. If hardware supports
* message registers, this event indicates, that a new message arrived in
* some incoming message register or last sent message couldn't be delivered.
* The events can be masked/unmasked by the methods ntb_msg_set_mask() and
* ntb_msg_clear_mask().
*/
void ntb_msg_event(struct ntb_dev *ntb);
/**
* ntb_default_port_number() - get the default local port number
* @ntb: NTB device context.
@ -1282,4 +1325,166 @@ static inline int ntb_peer_spad_write(struct ntb_dev *ntb, int pidx, int sidx,
return ntb->ops->peer_spad_write(ntb, pidx, sidx, val);
}
/**
* ntb_msg_count() - get the number of message registers
* @ntb: NTB device context.
*
* Hardware may support a different number of message registers.
*
* Return: the number of message registers.
*/
static inline int ntb_msg_count(struct ntb_dev *ntb)
{
if (!ntb->ops->msg_count)
return 0;
return ntb->ops->msg_count(ntb);
}
/**
* ntb_msg_inbits() - get a bitfield of inbound message registers status
* @ntb: NTB device context.
*
* The method returns the bitfield of status and mask registers, which related
* to inbound message registers.
*
* Return: bitfield of inbound message registers.
*/
static inline u64 ntb_msg_inbits(struct ntb_dev *ntb)
{
if (!ntb->ops->msg_inbits)
return 0;
return ntb->ops->msg_inbits(ntb);
}
/**
* ntb_msg_outbits() - get a bitfield of outbound message registers status
* @ntb: NTB device context.
*
* The method returns the bitfield of status and mask registers, which related
* to outbound message registers.
*
* Return: bitfield of outbound message registers.
*/
static inline u64 ntb_msg_outbits(struct ntb_dev *ntb)
{
if (!ntb->ops->msg_outbits)
return 0;
return ntb->ops->msg_outbits(ntb);
}
/**
* ntb_msg_read_sts() - read the message registers status
* @ntb: NTB device context.
*
* Read the status of message register. Inbound and outbound message registers
* related bits can be filtered by masks retrieved from ntb_msg_inbits() and
* ntb_msg_outbits().
*
* Return: status bits of message registers
*/
static inline u64 ntb_msg_read_sts(struct ntb_dev *ntb)
{
if (!ntb->ops->msg_read_sts)
return 0;
return ntb->ops->msg_read_sts(ntb);
}
/**
* ntb_msg_clear_sts() - clear status bits of message registers
* @ntb: NTB device context.
* @sts_bits: Status bits to clear.
*
* Clear bits in the status register.
*
* Return: Zero on success, otherwise a negative error number.
*/
static inline int ntb_msg_clear_sts(struct ntb_dev *ntb, u64 sts_bits)
{
if (!ntb->ops->msg_clear_sts)
return -EINVAL;
return ntb->ops->msg_clear_sts(ntb, sts_bits);
}
/**
* ntb_msg_set_mask() - set mask of message register status bits
* @ntb: NTB device context.
* @mask_bits: Mask bits.
*
* Mask the message registers status bits from raising the message event.
*
* Return: Zero on success, otherwise a negative error number.
*/
static inline int ntb_msg_set_mask(struct ntb_dev *ntb, u64 mask_bits)
{
if (!ntb->ops->msg_set_mask)
return -EINVAL;
return ntb->ops->msg_set_mask(ntb, mask_bits);
}
/**
* ntb_msg_clear_mask() - clear message registers mask
* @ntb: NTB device context.
* @mask_bits: Mask bits to clear.
*
* Clear bits in the message events mask register.
*
* Return: Zero on success, otherwise a negative error number.
*/
static inline int ntb_msg_clear_mask(struct ntb_dev *ntb, u64 mask_bits)
{
if (!ntb->ops->msg_clear_mask)
return -EINVAL;
return ntb->ops->msg_clear_mask(ntb, mask_bits);
}
/**
* ntb_msg_read() - read message register with specified index
* @ntb: NTB device context.
* @midx: Message register index
* @pidx: OUT - Port index of peer device a message retrieved from
* @msg: OUT - Data
*
* Read data from the specified message register. Source port index of a
* message is retrieved as well.
*
* Return: Zero on success, otherwise a negative error number.
*/
static inline int ntb_msg_read(struct ntb_dev *ntb, int midx, int *pidx,
u32 *msg)
{
if (!ntb->ops->msg_read)
return -EINVAL;
return ntb->ops->msg_read(ntb, midx, pidx, msg);
}
/**
* ntb_msg_write() - write data to the specified message register
* @ntb: NTB device context.
* @midx: Message register index
* @pidx: Port index of peer device a message being sent to
* @msg: Data to send
*
* Send data to a specified peer device using the defined message register.
* Message event can be raised if the midx registers isn't empty while
* calling this method and the corresponding interrupt isn't masked.
*
* Return: Zero on success, otherwise a negative error number.
*/
static inline int ntb_msg_write(struct ntb_dev *ntb, int midx, int pidx,
u32 msg)
{
if (!ntb->ops->msg_write)
return -EINVAL;
return ntb->ops->msg_write(ntb, midx, pidx, msg);
}
#endif