From 54e8f88d2baa104dee179ebd3c3325b93383e7d2 Mon Sep 17 00:00:00 2001 From: Jorge Ramirez-Ortiz Date: Wed, 3 Jan 2024 12:29:11 +0100 Subject: [PATCH] mmc: core: Do not force a retune before RPMB switch commit 67380251e8bbd3302c64fea07f95c31971b91c22 upstream. Requesting a retune before switching to the RPMB partition has been observed to cause CRC errors on the RPMB reads (-EILSEQ). Since RPMB reads can not be retried, the clients would be directly affected by the errors. This commit disables the retune request prior to switching to the RPMB partition: mmc_retune_pause() no longer triggers a retune before the pause period begins. This was verified with the sdhci-of-arasan driver (ZynqMP) configured for HS200 using two separate eMMC cards (DG4064 and 064GB2). In both cases, the error was easy to reproduce triggering every few tenths of reads. With this commit, systems that were utilizing OP-TEE to access RPMB variables will experience an enhanced performance. Specifically, when OP-TEE is configured to employ RPMB as a secure storage solution, it not only writes the data but also the secure filesystem within the partition. As a result, retrieving any variable involves multiple RPMB reads, typically around five. For context, on ZynqMP, each retune request consumed approximately 8ms. Consequently, reading any RPMB variable used to take at the very minimum 40ms. After droping the need to retune before switching to the RPMB partition, this is no longer the case. Signed-off-by: Jorge Ramirez-Ortiz Acked-by: Avri Altman Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/20240103112911.2954632-1-jorge@foundries.io Signed-off-by: Ulf Hansson Signed-off-by: Florian Fainelli Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/core/host.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index b949a4468bf5..7ba1343ca5c1 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -114,13 +114,12 @@ void mmc_retune_enable(struct mmc_host *host) /* * Pause re-tuning for a small set of operations. The pause begins after the - * next command and after first doing re-tuning. + * next command. */ void mmc_retune_pause(struct mmc_host *host) { if (!host->retune_paused) { host->retune_paused = 1; - mmc_retune_needed(host); mmc_retune_hold(host); } }