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 adds devm_ioremap_uc as a new managed wrapper to ioremap_uc
and with it overwrite the MTRR settings to force 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
Signed-off-by: Tuowen Zhao <[email protected]>
---
Changes from previous version:
* changed commit message
drivers/mfd/intel-lpss.c | 2 +-
include/linux/io.h | 2 ++
lib/devres.c | 19 +++++++++++++++++++
3 files changed, 22 insertions(+), 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;
diff --git a/include/linux/io.h b/include/linux/io.h
index accac822336a..a59834bc0a11 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -64,6 +64,8 @@ static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
resource_size_t size);
+void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
+ resource_size_t size);
void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
resource_size_t size);
void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
diff --git a/lib/devres.c b/lib/devres.c
index 6a0e9bd6524a..beb0a064b891 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -9,6 +9,7 @@
enum devm_ioremap_type {
DEVM_IOREMAP = 0,
DEVM_IOREMAP_NC,
+ DEVM_IOREMAP_UC,
DEVM_IOREMAP_WC,
};
@@ -39,6 +40,9 @@ static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
case DEVM_IOREMAP_NC:
addr = ioremap_nocache(offset, size);
break;
+ case DEVM_IOREMAP_UC:
+ addr = ioremap_uc(offset, size);
+ break;
case DEVM_IOREMAP_WC:
addr = ioremap_wc(offset, size);
break;
@@ -68,6 +72,21 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
}
EXPORT_SYMBOL(devm_ioremap);
+/**
+ * devm_ioremap_uc - Managed ioremap_uc()
+ * @dev: Generic device to remap IO address for
+ * @offset: Resource address to map
+ * @size: Size of map
+ *
+ * Managed ioremap_uc(). Map is automatically unmapped on driver detach.
+ */
+void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
+ resource_size_t size)
+{
+ return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_UC);
+}
+EXPORT_SYMBOL(devm_ioremap_uc);
+
/**
* devm_ioremap_nocache - Managed ioremap_nocache()
* @dev: Generic device to remap IO address for
--
2.23.0
Confirmed the patch works well on Dell XPS 7390 2-in-1 machine.
Tested-by: AceLan Kao <[email protected]>
Tuowen Zhao <[email protected]> 於 2019年10月8日 週二 上午2:43寫道：
>
> 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 adds devm_ioremap_uc as a new managed wrapper to ioremap_uc
> and with it overwrite the MTRR settings to force 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
> Signed-off-by: Tuowen Zhao <[email protected]>
> ---
> Changes from previous version:
>
> * changed commit message
>
> drivers/mfd/intel-lpss.c | 2 +-
> include/linux/io.h | 2 ++
> lib/devres.c | 19 +++++++++++++++++++
> 3 files changed, 22 insertions(+), 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;
> diff --git a/include/linux/io.h b/include/linux/io.h
> index accac822336a..a59834bc0a11 100644
> --- a/include/linux/io.h
> +++ b/include/linux/io.h
> @@ -64,6 +64,8 @@ static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
>
> void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
> resource_size_t size);
> +void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
> + resource_size_t size);
> void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
> resource_size_t size);
> void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
> diff --git a/lib/devres.c b/lib/devres.c
> index 6a0e9bd6524a..beb0a064b891 100644
> --- a/lib/devres.c
> +++ b/lib/devres.c
> @@ -9,6 +9,7 @@
> enum devm_ioremap_type {
> DEVM_IOREMAP = 0,
> DEVM_IOREMAP_NC,
> + DEVM_IOREMAP_UC,
> DEVM_IOREMAP_WC,
> };
>
> @@ -39,6 +40,9 @@ static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
> case DEVM_IOREMAP_NC:
> addr = ioremap_nocache(offset, size);
> break;
> + case DEVM_IOREMAP_UC:
> + addr = ioremap_uc(offset, size);
> + break;
> case DEVM_IOREMAP_WC:
> addr = ioremap_wc(offset, size);
> break;
> @@ -68,6 +72,21 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
> }
> EXPORT_SYMBOL(devm_ioremap);
>
> +/**
> + * devm_ioremap_uc - Managed ioremap_uc()
> + * @dev: Generic device to remap IO address for
> + * @offset: Resource address to map
> + * @size: Size of map
> + *
> + * Managed ioremap_uc(). Map is automatically unmapped on driver detach.
> + */
> +void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
> + resource_size_t size)
> +{
> + return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_UC);
> +}
> +EXPORT_SYMBOL(devm_ioremap_uc);
> +
> /**
> * devm_ioremap_nocache - Managed ioremap_nocache()
> * @dev: Generic device to remap IO address for
> --
> 2.23.0
>
On Mon, Oct 07, 2019 at 12:42:31PM -0600, Tuowen Zhao wrote:
> 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 adds devm_ioremap_uc as a new managed wrapper to ioremap_uc
> and with it overwrite the MTRR settings to force 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
> Signed-off-by: Tuowen Zhao <[email protected]>
Acked-by: Mika Westerberg <[email protected]>
On Mon, Oct 07, 2019 at 12:42:31PM -0600, Tuowen Zhao wrote:
> 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 adds devm_ioremap_uc as a new managed wrapper to ioremap_uc
> and with it overwrite the MTRR settings to force 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)
>
Acked-by: Andy Shevchenko <[email protected]>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=203485
> Signed-off-by: Tuowen Zhao <[email protected]>
> ---
> Changes from previous version:
>
> * changed commit message
>
> drivers/mfd/intel-lpss.c | 2 +-
> include/linux/io.h | 2 ++
> lib/devres.c | 19 +++++++++++++++++++
> 3 files changed, 22 insertions(+), 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;
> diff --git a/include/linux/io.h b/include/linux/io.h
> index accac822336a..a59834bc0a11 100644
> --- a/include/linux/io.h
> +++ b/include/linux/io.h
> @@ -64,6 +64,8 @@ static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
>
> void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
> resource_size_t size);
> +void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
> + resource_size_t size);
> void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
> resource_size_t size);
> void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
> diff --git a/lib/devres.c b/lib/devres.c
> index 6a0e9bd6524a..beb0a064b891 100644
> --- a/lib/devres.c
> +++ b/lib/devres.c
> @@ -9,6 +9,7 @@
> enum devm_ioremap_type {
> DEVM_IOREMAP = 0,
> DEVM_IOREMAP_NC,
> + DEVM_IOREMAP_UC,
> DEVM_IOREMAP_WC,
> };
>
> @@ -39,6 +40,9 @@ static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
> case DEVM_IOREMAP_NC:
> addr = ioremap_nocache(offset, size);
> break;
> + case DEVM_IOREMAP_UC:
> + addr = ioremap_uc(offset, size);
> + break;
> case DEVM_IOREMAP_WC:
> addr = ioremap_wc(offset, size);
> break;
> @@ -68,6 +72,21 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
> }
> EXPORT_SYMBOL(devm_ioremap);
>
> +/**
> + * devm_ioremap_uc - Managed ioremap_uc()
> + * @dev: Generic device to remap IO address for
> + * @offset: Resource address to map
> + * @size: Size of map
> + *
> + * Managed ioremap_uc(). Map is automatically unmapped on driver detach.
> + */
> +void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
> + resource_size_t size)
> +{
> + return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_UC);
> +}
> +EXPORT_SYMBOL(devm_ioremap_uc);
> +
> /**
> * devm_ioremap_nocache - Managed ioremap_nocache()
> * @dev: Generic device to remap IO address for
> --
> 2.23.0
>
--
With Best Regards,
Andy Shevchenko
On Mon, Oct 07, 2019 at 12:42:31PM -0600, Tuowen Zhao wrote:
> +EXPORT_SYMBOL(devm_ioremap_uc);
EXPORT_SYMBOL_GPL() would be my preference.
Luis
On Tue, Oct 08, 2019 at 03:16:28PM +0000, Luis Chamberlain wrote:
> On Mon, Oct 07, 2019 at 12:42:31PM -0600, Tuowen Zhao wrote:
> > +EXPORT_SYMBOL(devm_ioremap_uc);
>
> EXPORT_SYMBOL_GPL() would be my preference.
Maybe we can even split this to two patches?
--
With Best Regards,
Andy Shevchenko
I think that's a fair point. Sorry for not noticing it earlier.
> On Tue, Oct 8, 2019, 6:12 PM Andy Shevchenko <
> [email protected]> wrote:
> > Maybe we can even split this to two patches?
I assume splitting means one to add devm_ioremap_uc and one to use it
for intel-lpss-pci.
Tuowen
On Wed, Oct 9, 2019 at 12:09 AM GMAIL <[email protected]> wrote:
>
> I think that's a fair point. Sorry for not noticing it earlier.
>
> > On Tue, Oct 8, 2019, 6:12 PM Andy Shevchenko <
> > [email protected]> wrote:
> > > Maybe we can even split this to two patches?
>
> I assume splitting means one to add devm_ioremap_uc and one to use it
> for intel-lpss-pci.
Yes. And please, include Luis to Cc list.
--
With Best Regards,
Andy Shevchenko