From ff6a4f263bd1b1450a867ee1973f2e17b937bed3 Mon Sep 17 00:00:00 2001 From: Roy Pledge Date: Fri, 28 Sep 2018 11:43:23 +0300 Subject: [PATCH] soc: fsl: qbman: Use last response to determine valid bit Use the last valid response when determining what valid bit to use next for management commands. This is needed in the case that the portal was previously used by other software like a bootloader or if the kernel is restarted without a hardware reset. Signed-off-by: Roy Pledge Signed-off-by: Madalin Bucur Signed-off-by: Li Yang --- drivers/soc/fsl/qbman/qman.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/soc/fsl/qbman/qman.c b/drivers/soc/fsl/qbman/qman.c index 1897144b92816..b10a5880a4687 100644 --- a/drivers/soc/fsl/qbman/qman.c +++ b/drivers/soc/fsl/qbman/qman.c @@ -850,12 +850,24 @@ static inline void qm_mr_set_ithresh(struct qm_portal *portal, u8 ithresh) static inline int qm_mc_init(struct qm_portal *portal) { + u8 rr0, rr1; struct qm_mc *mc = &portal->mc; mc->cr = portal->addr.ce + QM_CL_CR; mc->rr = portal->addr.ce + QM_CL_RR0; - mc->rridx = (mc->cr->_ncw_verb & QM_MCC_VERB_VBIT) - ? 0 : 1; + /* + * The expected valid bit polarity for the next CR command is 0 + * if RR1 contains a valid response, and is 1 if RR0 contains a + * valid response. If both RR contain all 0, this indicates either + * that no command has been executed since reset (in which case the + * expected valid bit polarity is 1) + */ + rr0 = mc->rr->verb; + rr1 = (mc->rr+1)->verb; + if ((rr0 == 0 && rr1 == 0) || rr0 != 0) + mc->rridx = 1; + else + mc->rridx = 0; mc->vbit = mc->rridx ? QM_MCC_VERB_VBIT : 0; #ifdef CONFIG_FSL_DPAA_CHECKING mc->state = qman_mc_idle; -- 2.39.5