From: Bhupesh Sharma Date: Mon, 30 Sep 2024 12:44:32 +0000 (+0200) Subject: ufs: Add missing memory barriers X-Git-Url: http://git.dujemihanovic.xyz/html/%7B%7B%20.Permalink%20%7D%7D?a=commitdiff_plain;h=5ce1a2c7de4936d19cbc0307be734aed9f8056a4;p=u-boot.git ufs: Add missing memory barriers Add missing wmb() and mb() barriers in the u-boot UFS core framework driver to allow registers updates to happen before follow-up read operations. This makes the barrier placement similar to the Linux UFS driver, synced from the Linux v6.9 release. Starting from the v6.10 release, the barriers were replaced with a register read-back in [1], this will ported to u-boot in a second time. [1] https://lore.kernel.org/all/20240329-ufs-reset-ensure-effect-before-delay-v5-0-181252004586@redhat.com/ Signed-off-by: Bhupesh Sharma Tested-by: Venkatesh Yadav Abbarapu Tested-by: Julius Lehmann Link: https://lore.kernel.org/r/20240930-topic-ufs-enhancements-v3-10-58234f84ab89@linaro.org Signed-off-by: Neil Armstrong --- diff --git a/drivers/ufs/ufs.c b/drivers/ufs/ufs.c index 565a6af140..5d4e542435 100644 --- a/drivers/ufs/ufs.c +++ b/drivers/ufs/ufs.c @@ -432,6 +432,12 @@ static int ufshcd_make_hba_operational(struct ufs_hba *hba) ufshcd_writel(hba, upper_32_bits((dma_addr_t)hba->utmrdl), REG_UTP_TASK_REQ_LIST_BASE_H); + /* + * Make sure base address and interrupt setup are updated before + * enabling the run/stop registers below. + */ + wmb(); + /* * UCRDY, UTMRLDY and UTRLRDY bits must be 1 */ @@ -861,6 +867,9 @@ static int ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag) ufshcd_writel(hba, 1 << task_tag, REG_UTP_TRANSFER_REQ_DOOR_BELL); + /* Make sure doorbell reg is updated before reading interrupt status */ + wmb(); + start = get_timer(0); do { intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS); @@ -1994,6 +2003,8 @@ int ufshcd_probe(struct udevice *ufs_dev, struct ufs_hba_ops *hba_ops) REG_INTERRUPT_STATUS); ufshcd_writel(hba, 0, REG_INTERRUPT_ENABLE); + mb(); + err = ufshcd_hba_enable(hba); if (err) { dev_err(hba->dev, "Host controller enable failed\n");