After system suspend, CQE is in cqhci_off state, which set the HALT bit, make
CQE in HALT state. If the SoC do not power down the USDHC module, then when
system resume back, this bit keep the same, still set. So need to clear this
bit when enable CQE for the first request after system resume back. If not,
CQE will stuck in the first CMDQ request after system resume back.
Find this issue on NXP i.MX845s-mek board
[ 105.919862] mmc2: cqhci: timeout for tag 6
[ 105.923965] mmc2: cqhci: ============ CQHCI REGISTER DUMP ===========
[ 105.930407] mmc2: cqhci: Caps: 0x0000310a | Version: 0x00000510
[ 105.936847] mmc2: cqhci: Config: 0x00001001 | Control: 0x00000001
[ 105.943286] mmc2: cqhci: Int stat: 0x00000000 | Int enab: 0x00000006
[ 105.949725] mmc2: cqhci: Int sig: 0x00000006 | Int Coal: 0x00000000
[ 105.956164] mmc2: cqhci: TDL base: 0x7809b000 | TDL up32: 0x00000000
[ 105.962604] mmc2: cqhci: Doorbell: 0x00000040 | TCN: 0x00000000
[ 105.969043] mmc2: cqhci: Dev queue: 0x00000000 | Dev Pend: 0x00000000
[ 105.975483] mmc2: cqhci: Task clr: 0x00000000 | SSC1: 0x00011000
[ 105.981922] mmc2: cqhci: SSC2: 0x00000001 | DCMD rsp: 0x00000000
[ 105.988362] mmc2: cqhci: RED mask: 0xfdf9a080 | TERRI: 0x00000000
[ 105.994801] mmc2: cqhci: Resp idx: 0x00000000 | Resp arg: 0x00000000
[ 106.001240] mmc2: sdhci: ============ SDHCI REGISTER DUMP ===========
[ 106.007680] mmc2: sdhci: Sys addr: 0xb2b37800 | Version: 0x00000002
[ 106.014120] mmc2: sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000001
[ 106.020560] mmc2: sdhci: Argument: 0x00010000 | Trn mode: 0x00000013
[ 106.026999] mmc2: sdhci: Present: 0x01f88008 | Host ctl: 0x00000030
[ 106.033439] mmc2: sdhci: Power: 0x00000002 | Blk gap: 0x00000080
[ 106.039878] mmc2: sdhci: Wake-up: 0x00000008 | Clock: 0x0000000f
[ 106.046318] mmc2: sdhci: Timeout: 0x0000008f | Int stat: 0x00000000
[ 106.052757] mmc2: sdhci: Int enab: 0x107f4000 | Sig enab: 0x107f4000
[ 106.059196] mmc2: sdhci: AC12 err: 0x00000000 | Slot int: 0x00000502
[ 106.065635] mmc2: sdhci: Caps: 0x07eb0000 | Caps_1: 0x8000b407
[ 106.072075] mmc2: sdhci: Cmd: 0x00000d1a | Max curr: 0x00ffffff
[ 106.078514] mmc2: sdhci: Resp[0]: 0x00000900 | Resp[1]: 0x31360181
[ 106.084954] mmc2: sdhci: Resp[2]: 0x44473430 | Resp[3]: 0x00450100
[ 106.091392] mmc2: sdhci: Host ctl2: 0x00000008
[ 106.095836] mmc2: sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x7804b208
[ 106.102274] mmc2: sdhci: ============================================
[ 106.108785] mmc2: running CQE recovery
Signed-off-by: Haibo Chen <haibo.chen@xxxxxxx>
---
drivers/mmc/host/cqhci.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/mmc/host/cqhci.c b/drivers/mmc/host/cqhci.c
index 159270e947cf..48550c572bb6 100644
--- a/drivers/mmc/host/cqhci.c
+++ b/drivers/mmc/host/cqhci.c
@@ -271,6 +271,12 @@ static void __cqhci_enable(struct cqhci_host *cq_host)
cqhci_writel(cq_host, cqcfg, CQHCI_CFG);
+ /* Clear halt and clear all tasks */
+ cqhci_writel(cq_host, 0, CQHCI_CTL);
+ if (cqhci_readl(cq_host, CQHCI_CTL) && CQHCI_HALT)
+ pr_err("%s: cqhci: failed to exit halt state when enable CQE\n",
+ mmc_hostname(mmc));
+
mmc->cqe_on = true;
if (cq_host->ops->enable)
--
2.17.1
