From b3e6b4bdbb609762d8401ac4a959d590b4e4e3b8 Mon Sep 17 00:00:00 2001 From: "Byczkowski, Jakub" Date: Fri, 12 May 2017 09:01:37 -0700 Subject: [PATCH] RDMA/hfi1: Defer setting VL15 credits to link-up interrupt Keep VL15 credits at 0 during LNI, before link-up. Store VL15 credits value during verify cap interrupt and set in after link-up. This addresses an issue where VL15 MAD packets could be sent by one side of the link before the other side is ready to receive them. Reviewed-by: Mike Marciniszyn Reviewed-by: Dean Luick Reviewed-by: Dennis Dalessandro Signed-off-by: Jakub Byczkowski Signed-off-by: Dennis Dalessandro Signed-off-by: Doug Ledford --- drivers/infiniband/hw/hfi1/chip.c | 67 +++++++++++++++------ drivers/infiniband/hw/hfi1/chip_registers.h | 2 + drivers/infiniband/hw/hfi1/hfi.h | 11 +++- drivers/infiniband/hw/hfi1/intr.c | 3 +- 4 files changed, 64 insertions(+), 19 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c index 5d6b1eeaa9a0..2ba00b89df6a 100644 --- a/drivers/infiniband/hw/hfi1/chip.c +++ b/drivers/infiniband/hw/hfi1/chip.c @@ -6312,25 +6312,38 @@ static void handle_8051_request(struct hfi1_pportdata *ppd) } } -static void write_global_credit(struct hfi1_devdata *dd, - u8 vau, u16 total, u16 shared) +/* + * Set up allocation unit vaulue. + */ +void set_up_vau(struct hfi1_devdata *dd, u8 vau) { - write_csr(dd, SEND_CM_GLOBAL_CREDIT, - ((u64)total << - SEND_CM_GLOBAL_CREDIT_TOTAL_CREDIT_LIMIT_SHIFT) | - ((u64)shared << - SEND_CM_GLOBAL_CREDIT_SHARED_LIMIT_SHIFT) | - ((u64)vau << SEND_CM_GLOBAL_CREDIT_AU_SHIFT)); + u64 reg = read_csr(dd, SEND_CM_GLOBAL_CREDIT); + + /* do not modify other values in the register */ + reg &= ~SEND_CM_GLOBAL_CREDIT_AU_SMASK; + reg |= (u64)vau << SEND_CM_GLOBAL_CREDIT_AU_SHIFT; + write_csr(dd, SEND_CM_GLOBAL_CREDIT, reg); } /* * Set up initial VL15 credits of the remote. Assumes the rest of - * the CM credit registers are zero from a previous global or credit reset . + * the CM credit registers are zero from a previous global or credit reset. + * Shared limit for VL15 will always be 0. */ -void set_up_vl15(struct hfi1_devdata *dd, u8 vau, u16 vl15buf) +void set_up_vl15(struct hfi1_devdata *dd, u16 vl15buf) { - /* leave shared count at zero for both global and VL15 */ - write_global_credit(dd, vau, vl15buf, 0); + u64 reg = read_csr(dd, SEND_CM_GLOBAL_CREDIT); + + /* set initial values for total and shared credit limit */ + reg &= ~(SEND_CM_GLOBAL_CREDIT_TOTAL_CREDIT_LIMIT_SMASK | + SEND_CM_GLOBAL_CREDIT_SHARED_LIMIT_SMASK); + + /* + * Set total limit to be equal to VL15 credits. + * Leave shared limit at 0. + */ + reg |= (u64)vl15buf << SEND_CM_GLOBAL_CREDIT_TOTAL_CREDIT_LIMIT_SHIFT; + write_csr(dd, SEND_CM_GLOBAL_CREDIT, reg); write_csr(dd, SEND_CM_CREDIT_VL15, (u64)vl15buf << SEND_CM_CREDIT_VL15_DEDICATED_LIMIT_VL_SHIFT); @@ -6348,9 +6361,11 @@ void reset_link_credits(struct hfi1_devdata *dd) for (i = 0; i < TXE_NUM_DATA_VL; i++) write_csr(dd, SEND_CM_CREDIT_VL + (8 * i), 0); write_csr(dd, SEND_CM_CREDIT_VL15, 0); - write_global_credit(dd, 0, 0, 0); + write_csr(dd, SEND_CM_GLOBAL_CREDIT, 0); /* reset the CM block */ pio_send_control(dd, PSC_CM_RESET); + /* reset cached value */ + dd->vl15buf_cached = 0; } /* convert a vCU to a CU */ @@ -6839,24 +6854,35 @@ void handle_link_up(struct work_struct *work) { struct hfi1_pportdata *ppd = container_of(work, struct hfi1_pportdata, link_up_work); + struct hfi1_devdata *dd = ppd->dd; + set_link_state(ppd, HLS_UP_INIT); /* cache the read of DC_LCB_STS_ROUND_TRIP_LTP_CNT */ - read_ltp_rtt(ppd->dd); + read_ltp_rtt(dd); /* * OPA specifies that certain counters are cleared on a transition * to link up, so do that. */ - clear_linkup_counters(ppd->dd); + clear_linkup_counters(dd); /* * And (re)set link up default values. */ set_linkup_defaults(ppd); + /* + * Set VL15 credits. Use cached value from verify cap interrupt. + * In case of quick linkup or simulator, vl15 value will be set by + * handle_linkup_change. VerifyCap interrupt handler will not be + * called in those scenarios. + */ + if (!(quick_linkup || dd->icode == ICODE_FUNCTIONAL_SIMULATOR)) + set_up_vl15(dd, dd->vl15buf_cached); + /* enforce link speed enabled */ if ((ppd->link_speed_active & ppd->link_speed_enabled) == 0) { /* oops - current speed is not enabled, bounce */ - dd_dev_err(ppd->dd, + dd_dev_err(dd, "Link speed active 0x%x is outside enabled 0x%x, downing link\n", ppd->link_speed_active, ppd->link_speed_enabled); set_link_down_reason(ppd, OPA_LINKDOWN_REASON_SPEED_POLICY, 0, @@ -7357,7 +7383,14 @@ void handle_verify_cap(struct work_struct *work) */ if (vau == 0) vau = 1; - set_up_vl15(dd, vau, vl15buf); + set_up_vau(dd, vau); + + /* + * Set VL15 credits to 0 in global credit register. Cache remote VL15 + * credits value and wait for link-up interrupt ot set it. + */ + set_up_vl15(dd, 0); + dd->vl15buf_cached = vl15buf; /* set up the LCB CRC mode */ crc_mask = ppd->port_crc_mode_enabled & partner_supported_crc; diff --git a/drivers/infiniband/hw/hfi1/chip_registers.h b/drivers/infiniband/hw/hfi1/chip_registers.h index 5bfa839d1c48..793514f1d15f 100644 --- a/drivers/infiniband/hw/hfi1/chip_registers.h +++ b/drivers/infiniband/hw/hfi1/chip_registers.h @@ -839,7 +839,9 @@ #define SEND_CM_CTRL_FORCE_CREDIT_MODE_SMASK 0x8ull #define SEND_CM_CTRL_RESETCSR 0x0000000000000020ull #define SEND_CM_GLOBAL_CREDIT (TXE + 0x000000000508) +#define SEND_CM_GLOBAL_CREDIT_AU_MASK 0x7ull #define SEND_CM_GLOBAL_CREDIT_AU_SHIFT 16 +#define SEND_CM_GLOBAL_CREDIT_AU_SMASK 0x70000ull #define SEND_CM_GLOBAL_CREDIT_RESETCSR 0x0000094000030000ull #define SEND_CM_GLOBAL_CREDIT_SHARED_LIMIT_MASK 0xFFFFull #define SEND_CM_GLOBAL_CREDIT_SHARED_LIMIT_SHIFT 0 diff --git a/drivers/infiniband/hw/hfi1/hfi.h b/drivers/infiniband/hw/hfi1/hfi.h index da322e6668cc..414a04a481c2 100644 --- a/drivers/infiniband/hw/hfi1/hfi.h +++ b/drivers/infiniband/hw/hfi1/hfi.h @@ -1045,6 +1045,14 @@ struct hfi1_devdata { /* initial vl15 credits to use */ u16 vl15_init; + /* + * Cached value for vl15buf, read during verify cap interrupt. VL15 + * credits are to be kept at 0 and set when handling the link-up + * interrupt. This removes the possibility of receiving VL15 MAD + * packets before this HFI is ready. + */ + u16 vl15buf_cached; + /* Misc small ints */ u8 n_krcv_queues; u8 qos_shift; @@ -1598,7 +1606,8 @@ int hfi1_rcvbuf_validate(u32 size, u8 type, u16 *encode); int fm_get_table(struct hfi1_pportdata *ppd, int which, void *t); int fm_set_table(struct hfi1_pportdata *ppd, int which, void *t); -void set_up_vl15(struct hfi1_devdata *dd, u8 vau, u16 vl15buf); +void set_up_vau(struct hfi1_devdata *dd, u8 vau); +void set_up_vl15(struct hfi1_devdata *dd, u16 vl15buf); void reset_link_credits(struct hfi1_devdata *dd); void assign_remote_cm_au_table(struct hfi1_devdata *dd, u8 vcu); diff --git a/drivers/infiniband/hw/hfi1/intr.c b/drivers/infiniband/hw/hfi1/intr.c index ba265d0ae93b..04a5082d5ac5 100644 --- a/drivers/infiniband/hw/hfi1/intr.c +++ b/drivers/infiniband/hw/hfi1/intr.c @@ -130,7 +130,8 @@ void handle_linkup_change(struct hfi1_devdata *dd, u32 linkup) * the remote values. Both sides must be using the values. */ if (quick_linkup || dd->icode == ICODE_FUNCTIONAL_SIMULATOR) { - set_up_vl15(dd, dd->vau, dd->vl15_init); + set_up_vau(dd, dd->vau); + set_up_vl15(dd, dd->vl15_init); assign_remote_cm_au_table(dd, dd->vcu); } -- 2.30.2