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 <mike.marciniszyn@intel.com>
Reviewed-by: Dean Luick <dean.luick@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jakub Byczkowski <jakub.byczkowski@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Byczkowski, Jakub 2017-05-12 09:01:37 -07:00 committed by Doug Ledford
parent e4785b0633
commit b3e6b4bdbb
4 changed files with 64 additions and 19 deletions

View File

@ -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;

View File

@ -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

View File

@ -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);

View File

@ -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);
}