From 5c0f94088e0694220a2f0d8ad6e8216b50a80f2e Mon Sep 17 00:00:00 2001 From: Jonathan Bell Date: Thu, 13 Jun 2024 15:01:02 +0100 Subject: [PATCH 1133/1145] drivers: mmc: sdhci-brcmstb: improve bcm2712 card removal handling If the controller is being reset, then the CQE needs to be reset as well. For removable cards, CQHCI_SSC1 must specify a polling mode (CBC=0) otherwise it's possible that the controller stops emitting periodic CMD13s on card removal, without raising an error status interrupt. Signed-off-by: Jonathan Bell --- drivers/mmc/host/sdhci-brcmstb.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) --- a/drivers/mmc/host/sdhci-brcmstb.c +++ b/drivers/mmc/host/sdhci-brcmstb.c @@ -366,8 +366,21 @@ static void sdhci_brcmstb_cqe_enable(str sdhci_cqe_enable(mmc); - /* Reset CMD13 polling timer back to eMMC specification default */ - cqhci_writel(cq_host, 0x00011000, CQHCI_SSC1); + /* + * The controller resets this register to a very short default interval + * whenever CQHCI is disabled. + * + * For removable cards CBC needs to be clear or card removal can hang + * the CQE. In polling mode, a CIT of 0x4000 "cycles" seems to produce the best + * throughput. + * + * For nonremovable cards, the specification default of CBC=1 CIT=0x1000 + * suffices. + */ + if (mmc->caps & MMC_CAP_NONREMOVABLE) + cqhci_writel(cq_host, 0x00011000, CQHCI_SSC1); + else + cqhci_writel(cq_host, 0x00004000, CQHCI_SSC1); } static const struct cqhci_host_ops sdhci_brcmstb_cqhci_ops = { @@ -387,7 +400,7 @@ static struct sdhci_ops sdhci_brcmstb_op .set_clock = sdhci_bcm2712_set_clock, .set_power = sdhci_brcmstb_set_power, .set_bus_width = sdhci_set_bus_width, - .reset = sdhci_reset, + .reset = brcmstb_reset, .set_uhs_signaling = sdhci_set_uhs_signaling, .init_sd_express = bcm2712_init_sd_express, };