[PATCH V8 03/14] mmc: mmc: Enable Command Queuing

[Adrian Hunter <adrian.hunter@intel.com>]

Enable the Command Queue if the host controller supports a command queue
engine. It is not compatible with Packed Commands, so make a note of that in the
comment.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 drivers/mmc/core/mmc.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index a7eb623f8daa..194cf2082e73 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1784,6 +1784,23 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
 	}
 
 	/*
+	 * Enable Command Queue if supported. Note that Packed Commands cannot
+	 * be used with Command Queue.
+	 */
+	card->ext_csd.cmdq_en = false;
+	if (card->ext_csd.cmdq_support && host->caps2 & MMC_CAP2_CQE) {
+		err = mmc_cmdq_enable(card);
+		if (err && err != -EBADMSG)
+			goto free_card;
+		if (err) {
+			pr_warn("%s: Enabling CMDQ failed\n",
+				mmc_hostname(card->host));
+			card->ext_csd.cmdq_support = false;
+			card->ext_csd.cmdq_depth = 0;
+			err = 0;
+		}
+	}
+	/*
 	 * In some cases (e.g. RPMB or mmc_test), the Command Queue must be
 	 * disabled for a time, so a flag is needed to indicate to re-enable the
 	 * Command Queue.
-- 
1.9.1