target/linux/generic/backport-5.10/801-v5.11-0002-nvmem-qfprom-Don-t-touch-certain-fuses.patch

   1 From 044ee8f85267599a9b0112911f5c16d4548b4289 Mon Sep 17 00:00:00 2001
   2 From: Evan Green <evgreen@chromium.org>
   3 Date: Fri, 27 Nov 2020 10:28:36 +0000
   4 Subject: [PATCH] nvmem: qfprom: Don't touch certain fuses
   5
   6 Some fuse ranges are protected by the XPU such that the AP cannot
   7 access them. Attempting to do so causes an SError. Use the newly
   8 introduced per-soc compatible string, and the newly introduced
   9 nvmem keepout support to attach the set of regions
  10 we should not access.
  11
  12 Reviewed-by: Douglas Anderson <dianders@chromium.org>
  13 Signed-off-by: Evan Green <evgreen@chromium.org>
  14 Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
  15 Link: https://lore.kernel.org/r/20201127102837.19366-5-srinivas.kandagatla@linaro.org
  16 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  17 ---
  18  drivers/nvmem/qfprom.c | 30 ++++++++++++++++++++++++++++++
  19  1 file changed, 30 insertions(+)
  20
  21 --- a/drivers/nvmem/qfprom.c
  22 +++ b/drivers/nvmem/qfprom.c
  23 @@ -12,6 +12,7 @@
  24  #include <linux/mod_devicetable.h>
  25  #include <linux/nvmem-provider.h>
  26  #include <linux/platform_device.h>
  27 +#include <linux/property.h>
  28  #include <linux/regulator/consumer.h>
  29
  30  /* Blow timer clock frequency in Mhz */
  31 @@ -89,6 +90,28 @@ struct qfprom_touched_values {
  32  };
  33
  34  /**
  35 + * struct qfprom_soc_compatible_data - Data matched against the SoC
  36 + * compatible string.
  37 + *
  38 + * @keepout: Array of keepout regions for this SoC.
  39 + * @nkeepout: Number of elements in the keepout array.
  40 + */
  41 +struct qfprom_soc_compatible_data {
  42 +       const struct nvmem_keepout *keepout;
  43 +       unsigned int nkeepout;
  44 +};
  45 +
  46 +static const struct nvmem_keepout sc7180_qfprom_keepout[] = {
  47 +       {.start = 0x128, .end = 0x148},
  48 +       {.start = 0x220, .end = 0x228}
  49 +};
  50 +
  51 +static const struct qfprom_soc_compatible_data sc7180_qfprom = {
  52 +       .keepout = sc7180_qfprom_keepout,
  53 +       .nkeepout = ARRAY_SIZE(sc7180_qfprom_keepout)
  54 +};
  55 +
  56 +/**
  57   * qfprom_disable_fuse_blowing() - Undo enabling of fuse blowing.
  58   * @priv: Our driver data.
  59   * @old:  The data that was stashed from before fuse blowing.
  60 @@ -302,6 +325,7 @@ static int qfprom_probe(struct platform_
  61         struct device *dev = &pdev->dev;
  62         struct resource *res;
  63         struct nvmem_device *nvmem;
  64 +       const struct qfprom_soc_compatible_data *soc_data;
  65         struct qfprom_priv *priv;
  66         int ret;
  67
  68 @@ -320,6 +344,11 @@ static int qfprom_probe(struct platform_
  69         econfig.priv = priv;
  70
  71         priv->dev = dev;
  72 +       soc_data = device_get_match_data(dev);
  73 +       if (soc_data) {
  74 +               econfig.keepout = soc_data->keepout;
  75 +               econfig.nkeepout = soc_data->nkeepout;
  76 +       }
  77
  78         /*
  79          * If more than one region is provided then the OS has the ability
  80 @@ -375,6 +404,7 @@ static int qfprom_probe(struct platform_
  81
  82  static const struct of_device_id qfprom_of_match[] = {
  83         { .compatible = "qcom,qfprom",},
  84 +       { .compatible = "qcom,sc7180-qfprom", .data = &sc7180_qfprom},
  85         {/* sentinel */},
  86  };
  87  MODULE_DEVICE_TABLE(of, qfprom_of_match);