diff options
Diffstat (limited to '0003-mfd-intel-lpss-Use-devm_ioremap_uc-for-MMIO.patch')
| -rw-r--r-- | 0003-mfd-intel-lpss-Use-devm_ioremap_uc-for-MMIO.patch | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/0003-mfd-intel-lpss-Use-devm_ioremap_uc-for-MMIO.patch b/0003-mfd-intel-lpss-Use-devm_ioremap_uc-for-MMIO.patch new file mode 100644 index 0000000..853d2b7 --- /dev/null +++ b/0003-mfd-intel-lpss-Use-devm_ioremap_uc-for-MMIO.patch @@ -0,0 +1,48 @@ +From 5408dcb0a652b76a5e190a68ce737a9a903cdfc0 Mon Sep 17 00:00:00 2001 +From: Tuowen Zhao <ztuowen@gmail.com> +Date: Wed, 16 Oct 2019 15:06:29 -0600 +Subject: mfd: intel-lpss: Use devm_ioremap_uc for MMIO + +Some BIOS erroneously specifies write-combining BAR for intel-lpss-pci +in MTRR. This will cause the system to hang during boot. If possible, +this bug could be corrected with a firmware update. + +This patch use devm_ioremap_uc to overwrite/ignore the MTRR settings +by forcing the use of strongly uncachable pages for intel-lpss. + +The BIOS bug is present on Dell XPS 13 7390 2-in-1: + +[ 0.001734] 5 base 4000000000 mask 6000000000 write-combining + +4000000000-7fffffffff : PCI Bus 0000:00 + 4000000000-400fffffff : 0000:00:02.0 (i915) + 4010000000-4010000fff : 0000:00:15.0 (intel-lpss-pci) + +Link: https://bugzilla.kernel.org/show_bug.cgi?id=203485 +Cc: <stable@vger.kernel.org> # v4.19+ +Tested-by: AceLan Kao <acelan.kao@canonical.com> +Signed-off-by: Tuowen Zhao <ztuowen@gmail.com> +Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> +Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> +Tested-by: Roman Gilg <subdiff@gmail.com> +Signed-off-by: Lee Jones <lee.jones@linaro.org> +--- + drivers/mfd/intel-lpss.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/drivers/mfd/intel-lpss.c b/drivers/mfd/intel-lpss.c +index bfe4ff337581..b0f0781a6b9c 100644 +--- a/drivers/mfd/intel-lpss.c ++++ b/drivers/mfd/intel-lpss.c +@@ -384,7 +384,7 @@ int intel_lpss_probe(struct device *dev, + if (!lpss) + return -ENOMEM; + +- lpss->priv = devm_ioremap(dev, info->mem->start + LPSS_PRIV_OFFSET, ++ lpss->priv = devm_ioremap_uc(dev, info->mem->start + LPSS_PRIV_OFFSET, + LPSS_PRIV_SIZE); + if (!lpss->priv) + return -ENOMEM; +-- +cgit v1.2.1-1-g437b + |