linux-kernel - [PATCH v1 2/2] mmc: core: No need to calculate the timeout value for CQE data transmission

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Date:   Tue,  7 Sep 2021 17:12:04 +0200
From:   Bean Huo <huobean@...il.com>
To:     ulf.hansson@...aro.org, adrian.hunter@...el.com,
        wsa+renesas@...g-engineering.com, linus.walleij@...aro.org,
        avri.altman@....com, linux-mmc@...r.kernel.org,
        linux-kernel@...r.kernel.org
Cc:     beanhuo@...ron.com
Subject: [PATCH v1 2/2] mmc: core: No need to calculate the timeout value for CQE data transmission

From: Bean Huo <beanhuo@...ron.com>

In case CQE is enabled, the timeout value of data transmission is always
set to be maximum in sdhci_cqe_enable(), so, calculating its timeout value
is obviously superfluous. Change to return directly, which can save some CPU
cycle time.

Signed-off-by: Bean Huo <beanhuo@...ron.com>
---
 drivers/mmc/core/core.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 240c5af793dc..0b571a3bc988 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -649,6 +649,7 @@ EXPORT_SYMBOL(mmc_wait_for_cmd);
 void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
 {
 	unsigned int mult;
+	struct mmc_host *host = card->host;
 
 	/*
 	 * SDIO cards only define an upper 1 s limit on access.
@@ -659,6 +660,13 @@ void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
 		return;
 	}
 
+	/*
+	 * In case CQE is enabled, the timeout will be set a maximum timeout in
+	 * sdhci_cqe_enable(), so, no need to go through the below algorithm.
+	 */
+	if (host->cqe_enabled)
+		return;
+
 	/*
 	 * SD cards use a 100 multiplier rather than 10
 	 */
-- 
2.25.1