AMD NTB support two features: flush pending requests and wakeup opposite side from low power state. This patch add two interface to support these features.
Signed-off-by: Xiangliang Yu <[email protected]> --- drivers/ntb/hw/amd/ntb_hw_amd.c | 40 ++++++++++++++++++++++++++++++++++++++-- drivers/ntb/hw/amd/ntb_hw_amd.h | 2 ++ include/linux/ntb.h | 35 +++++++++++++++++++++++++++++++++++ 3 files changed, 75 insertions(+), 2 deletions(-) diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.c b/drivers/ntb/hw/amd/ntb_hw_amd.c index cedac8d..6ca0191 100644 --- a/drivers/ntb/hw/amd/ntb_hw_amd.c +++ b/drivers/ntb/hw/amd/ntb_hw_amd.c @@ -93,6 +93,8 @@ static const struct ntb_dev_ops amd_ntb_ops = { .peer_spad_addr = amd_ntb_peer_spad_addr, .peer_spad_read = amd_ntb_peer_spad_read, .peer_spad_write = amd_ntb_peer_spad_write, + .flush_req = amd_ntb_flush_req, + .peer_wakeup = amd_ntb_wakeup_peer_side, }; static int ndev_mw_to_bar(struct amd_ntb_dev *ndev, int idx) @@ -489,7 +491,6 @@ static void amd_ack_SMU(struct amd_ntb_dev *ndev, u32 bit) ndev->peer_sta |= bit; } -#ifdef CONFIG_PM /* * flush the requests to peer side */ @@ -513,7 +514,42 @@ static int amd_flush_peer_requests(struct amd_ntb_dev *ndev) return 0; } -#endif + +static int amd_ntb_flush_req(struct ntb_dev *ntb) +{ + struct amd_ntb_dev *ndev = ntb_ndev(ntb); + + return amd_flush_peer_requests(ndev); +} + +/* + * wake up the peer side + */ +static int amd_wakeup_peer_side(struct amd_ntb_dev *ndev) +{ + void __iomem *mmio = ndev->self_mmio; + u32 reg; + + if (!amd_link_is_up(ndev)) { + dev_warn(ndev_dev(ndev), "link is down.\n"); + return -EINVAL; + } + + reg = NTB_READ_REG(mmio, PMSGTRIG); + reg |= 0x1; + NTB_WRITE_REG(mmio, reg, PMSGTRIG); + + wait_for_completion(&ndev->wakeup_cmpl); + + return 0; +} + +static int amd_ntb_wakeup_peer_side(struct ntb_dev *ntb) +{ + struct amd_ntb_dev *ndev = ntb_ndev(ntb); + + return amd_wakeup_peer_side(ndev); +} static void amd_handle_event(struct amd_ntb_dev *ndev, int vec) { diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.h b/drivers/ntb/hw/amd/ntb_hw_amd.h index 6005040..acf1d57 100644 --- a/drivers/ntb/hw/amd/ntb_hw_amd.h +++ b/drivers/ntb/hw/amd/ntb_hw_amd.h @@ -260,4 +260,6 @@ static int amd_ntb_peer_spad_addr(struct ntb_dev *ntb, int idx, phys_addr_t *spad_addr); static u32 amd_ntb_peer_spad_read(struct ntb_dev *ntb, int idx); static int amd_ntb_peer_spad_write(struct ntb_dev *ntb, int idx, u32 val); +static int amd_ntb_flush_req(struct ntb_dev *ntb); +static int amd_ntb_wakeup_peer_side(struct ntb_dev *ntb); #endif diff --git a/include/linux/ntb.h b/include/linux/ntb.h index f798e2a..ada98be 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -210,6 +210,8 @@ 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(). + * @flush_req: See ntb_flush_requests(). + * @peer_wakeup: See ntb_wakeup_peer_side(). */ struct ntb_dev_ops { int (*mw_count)(struct ntb_dev *ntb); @@ -259,6 +261,9 @@ struct ntb_dev_ops { phys_addr_t *spad_addr); u32 (*peer_spad_read)(struct ntb_dev *ntb, int idx); int (*peer_spad_write)(struct ntb_dev *ntb, int idx, u32 val); + + int (*flush_req)(struct ntb_dev *ntb); + int (*peer_wakeup)(struct ntb_dev *ntb); }; static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops) @@ -980,4 +985,34 @@ static inline int ntb_peer_spad_write(struct ntb_dev *ntb, int idx, u32 val) return ntb->ops->peer_spad_write(ntb, idx, val); } +/** + * ntb_flush_requests() - flush all pending requests + * @ntb: NTB device context. + * + * For some usage, one side of NTB need to first make sure that all previous + * requests have been completed and then execute next step such as power down, + * or device removed. + * NOTE: This function may go to sleep, so can't call it in interrupt context. + * + * Return: Zero on success, otherwise an error number. + */ +static inline int ntb_flush_requests(struct ntb_dev *ntb) +{ + return ntb->ops->flush_req(ntb); +} + +/** + * ntb_wakeup_peer_side() - wakeup peer side of NTB. + * @ntb: NTB device context. + * + * Provide a mechanism that wakeup opposite side from low power state. + * NOTE: This function may go to sleep, so can't call it in interrupt context. + * + * Return: Zero on success, otherwise an error number. + */ +static inline int ntb_wakeup_peer_side(struct ntb_dev *ntb) +{ + return ntb->ops->peer_wakeup(ntb); +} + #endif -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
