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| author | Jacob Keller <jacob.e.keller@intel.com> | 2024-08-06 13:46:21 -0700 |
|---|---|---|
| committer | Tony Nguyen <anthony.l.nguyen@intel.com> | 2024-08-26 09:34:38 -0700 |
| commit | 5f6df173f92eff2d6fa09d74e47e204b0072f82e (patch) | |
| tree | 088aeea5355c03631712846bb9079d9910e4697a /drivers/net/ethernet/intel/ice/ice_controlq.c | |
| parent | 18aaa82bd36ae3d4eaa3f1d1d8cf643e39f151cd (diff) | |
| download | lwn-5f6df173f92eff2d6fa09d74e47e204b0072f82e.tar.gz lwn-5f6df173f92eff2d6fa09d74e47e204b0072f82e.zip | |
ice: implement and use rd32_poll_timeout for ice_sq_done timeout
The ice_sq_done function is used to check the control queue head register
and determine whether or not the control queue processing is done. This
function is called in a loop checking against jiffies for a specified
timeout.
The pattern of reading a register in a loop until a condition is true or a
timeout is reached is a relatively common pattern. In fact, the kernel
provides a read_poll_timeout function implementing this behavior in
<linux/iopoll.h>
Use of read_poll_timeout is preferred over directly coding these loops.
However, using it in the ice driver is a bit more difficult because of the
rd32 wrapper. Implement a rd32_poll_timeout wrapper based on
read_poll_timeout.
Refactor ice_sq_done to use rd32_poll_timeout, replacing the loop calling
ice_sq_done in ice_sq_send_cmd. This simplifies the logic down to a single
ice_sq_done() call.
The implementation of rd32_poll_timeout uses microseconds for its timeout
value, so update the CQ timeout macros used to be specified in microseconds
units as well instead of using HZ for jiffies.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/ice/ice_controlq.c')
| -rw-r--r-- | drivers/net/ethernet/intel/ice/ice_controlq.c | 38 |
1 files changed, 18 insertions, 20 deletions
diff --git a/drivers/net/ethernet/intel/ice/ice_controlq.c b/drivers/net/ethernet/intel/ice/ice_controlq.c index ffaa6511c455..1b1b68a99bb2 100644 --- a/drivers/net/ethernet/intel/ice/ice_controlq.c +++ b/drivers/net/ethernet/intel/ice/ice_controlq.c @@ -933,19 +933,29 @@ static void ice_debug_cq(struct ice_hw *hw, void *desc, void *buf, u16 buf_len) } /** - * ice_sq_done - check if FW has processed the Admin Send Queue (ATQ) + * ice_sq_done - poll until the last send on a control queue has completed * @hw: pointer to the HW struct * @cq: pointer to the specific Control queue * - * Returns true if the firmware has processed all descriptors on the - * admin send queue. Returns false if there are still requests pending. + * Use read_poll_timeout to poll the control queue head, checking until it + * matches next_to_use. According to the control queue designers, this has + * better timing reliability than the DD bit. + * + * Return: true if all the descriptors on the send side of a control queue + * are finished processing, false otherwise. */ static bool ice_sq_done(struct ice_hw *hw, struct ice_ctl_q_info *cq) { - /* AQ designers suggest use of head for better - * timing reliability than DD bit + u32 head; + + /* Wait a short time before the initial check, to allow hardware time + * for completion. */ - return rd32(hw, cq->sq.head) == cq->sq.next_to_use; + udelay(5); + + return !rd32_poll_timeout(hw, cq->sq.head, + head, head == cq->sq.next_to_use, + 20, ICE_CTL_Q_SQ_CMD_TIMEOUT); } /** @@ -969,7 +979,6 @@ ice_sq_send_cmd(struct ice_hw *hw, struct ice_ctl_q_info *cq, struct ice_aq_desc *desc_on_ring; bool cmd_completed = false; struct ice_sq_cd *details; - unsigned long timeout; int status = 0; u16 retval = 0; u32 val = 0; @@ -1063,20 +1072,9 @@ ice_sq_send_cmd(struct ice_hw *hw, struct ice_ctl_q_info *cq, wr32(hw, cq->sq.tail, cq->sq.next_to_use); ice_flush(hw); - /* Wait a short time before initial ice_sq_done() check, to allow - * hardware time for completion. + /* Wait for the command to complete. If it finishes within the + * timeout, copy the descriptor back to temp. */ - udelay(5); - - timeout = jiffies + ICE_CTL_Q_SQ_CMD_TIMEOUT; - do { - if (ice_sq_done(hw, cq)) - break; - - usleep_range(100, 150); - } while (time_before(jiffies, timeout)); - - /* if ready, copy the desc back to temp */ if (ice_sq_done(hw, cq)) { memcpy(desc, desc_on_ring, sizeof(*desc)); if (buf) { |