git.openwrt.org Git - openwrt/openwrt.git/blob

   1 From 5c0f94088e0694220a2f0d8ad6e8216b50a80f2e Mon Sep 17 00:00:00 2001
   2 From: Jonathan Bell <jonathan@raspberrypi.com>
   3 Date: Thu, 13 Jun 2024 15:01:02 +0100
   4 Subject: [PATCH 1133/1145] drivers: mmc: sdhci-brcmstb: improve bcm2712 card
   5  removal handling
   6
   7 If the controller is being reset, then the CQE needs to be reset as well.
   8
   9 For removable cards, CQHCI_SSC1 must specify a polling mode (CBC=0)
  10 otherwise it's possible that the controller stops emitting periodic
  11 CMD13s on card removal, without raising an error status interrupt.
  12
  13 Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>
  14 ---
  15  drivers/mmc/host/sdhci-brcmstb.c | 19 ++++++++++++++++---
  16  1 file changed, 16 insertions(+), 3 deletions(-)
  17
  18 --- a/drivers/mmc/host/sdhci-brcmstb.c
  19 +++ b/drivers/mmc/host/sdhci-brcmstb.c
  20 @@ -365,8 +365,21 @@ static void sdhci_brcmstb_cqe_enable(str
  21
  22         sdhci_cqe_enable(mmc);
  23
  24 -       /* Reset CMD13 polling timer back to eMMC specification default */
  25 -       cqhci_writel(cq_host, 0x00011000, CQHCI_SSC1);
  26 +       /*
  27 +        * The controller resets this register to a very short default interval
  28 +        * whenever CQHCI is disabled.
  29 +        *
  30 +        * For removable cards CBC needs to be clear or card removal can hang
  31 +        * the CQE. In polling mode, a CIT of 0x4000 "cycles" seems to produce the best
  32 +        * throughput.
  33 +        *
  34 +        * For nonremovable cards, the specification default of CBC=1 CIT=0x1000
  35 +        * suffices.
  36 +        */
  37 +       if (mmc->caps & MMC_CAP_NONREMOVABLE)
  38 +               cqhci_writel(cq_host, 0x00011000, CQHCI_SSC1);
  39 +       else
  40 +               cqhci_writel(cq_host, 0x00004000, CQHCI_SSC1);
  41  }
  42
  43  static const struct cqhci_host_ops sdhci_brcmstb_cqhci_ops = {
  44 @@ -386,7 +399,7 @@ static struct sdhci_ops sdhci_brcmstb_op
  45         .set_clock = sdhci_bcm2712_set_clock,
  46         .set_power = sdhci_brcmstb_set_power,
  47         .set_bus_width = sdhci_set_bus_width,
  48 -       .reset = sdhci_reset,
  49 +       .reset = brcmstb_reset,
  50         .set_uhs_signaling = sdhci_set_uhs_signaling,
  51         .init_sd_express = bcm2712_init_sd_express,
  52  };