target/linux/layerscape/patches-5.4/701-net-0039-staging-fsl_qbman-Calculate-valid-bit-from-MC-RR.patch

   1 From 5ebee96094c5a97a89a986108242cca9d853ff55 Mon Sep 17 00:00:00 2001
   2 From: Roy Pledge <roy.pledge@nxp.com>
   3 Date: Wed, 27 Sep 2017 14:50:08 -0400
   4 Subject: [PATCH] staging/fsl_qbman: Calculate valid bit from MC-RR
   5
   6 Use the management commmand response registers to determine
   7 the next expected valid bit when initializing a software
   8 portal. This avoids using the wrong valid bit in cases
   9 where a command was partially written but then not
  10 completed.
  11
  12 Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
  13 ---
  14  drivers/staging/fsl_qbman/qman_low.h | 19 +++++++++++++++++--
  15  1 file changed, 17 insertions(+), 2 deletions(-)
  16
  17 --- a/drivers/staging/fsl_qbman/qman_low.h
  18 +++ b/drivers/staging/fsl_qbman/qman_low.h
  19 @@ -1095,11 +1095,26 @@ static inline void qm_mr_set_ithresh(str
  20
  21  static inline int qm_mc_init(struct qm_portal *portal)
  22  {
  23 +       u8 rr0, rr1;
  24         register struct qm_mc *mc = &portal->mc;
  25 +
  26         mc->cr = portal->addr.addr_ce + QM_CL_CR;
  27         mc->rr = portal->addr.addr_ce + QM_CL_RR0;
  28 -       mc->rridx = (__raw_readb(&mc->cr->__dont_write_directly__verb) &
  29 -                       QM_MCC_VERB_VBIT) ?  0 : 1;
  30 +
  31 +       /*
  32 +        * The expected valid bit polarity for the next CR command is 0
  33 +        * if RR1 contains a valid response, and is 1 if RR0 contains a
  34 +        * valid response. If both RR contain all 0, this indicates either
  35 +        * that no command has been executed since reset (in which case the
  36 +        * expected valid bit polarity is 1)
  37 +        */
  38 +       rr0 = __raw_readb(&mc->rr->verb);
  39 +       rr1 = __raw_readb(&(mc->rr+1)->verb);
  40 +       if ((rr0 == 0 && rr1 == 0) || rr0 != 0)
  41 +               mc->rridx = 1;
  42 +       else
  43 +               mc->rridx = 0;
  44 +
  45         mc->vbit = mc->rridx ? QM_MCC_VERB_VBIT : 0;
  46  #ifdef CONFIG_FSL_DPA_CHECKING
  47         mc->state = qman_mc_idle;