subject:"\[PATCH 4\/4\] iommu\/mediatek\: check 4GB mode by reading infracfg"

Re: [PATCH 4/4] iommu/mediatek: check 4GB mode by reading infracfg

2020-07-17 Thread Miles Chen

On Wed, 2020-07-15 at 23:05 +0200, Matthias Brugger wrote:
> 
> On 02/07/2020 11:37, Miles Chen wrote:
> > In previous disscusion [1] and [2], we found that it is risky to
> > use max_pfn or totalram_pages to tell if 4GB mode is enabled.
> > 
> > Check 4GB mode by reading infracfg register, remove the usage
> > of the unexported symbol max_pfn.
> > 
> > [1] 
> > https://urldefense.com/v3/__https://lkml.org/lkml/2020/6/3/733__;!!CTRNKA9wMg0ARbw!16gAfVnSY87W4t5kE4iw20QPxBgS_SHBvPKlePKU7CGIb18nUzuRUjHumcf4oYVhIQ$
> >  
> > [2] 
> > https://urldefense.com/v3/__https://lkml.org/lkml/2020/6/4/136__;!!CTRNKA9wMg0ARbw!16gAfVnSY87W4t5kE4iw20QPxBgS_SHBvPKlePKU7CGIb18nUzuRUjHumcfr4i9p5g$
> >  
> > 
> > Cc: Mike Rapoport 
> > Cc: David Hildenbrand 
> > Cc: Yong Wu 
> > Cc: Yingjoe Chen 
> > Cc: Christoph Hellwig 
> > Signed-off-by: Miles Chen 
> > ---
> >   drivers/iommu/mtk_iommu.c | 22 ++
> >   1 file changed, 18 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> > index 2be96f1cdbd2..09be57bd8d74 100644
> > --- a/drivers/iommu/mtk_iommu.c
> > +++ b/drivers/iommu/mtk_iommu.c
> > @@ -3,7 +3,6 @@
> >* Copyright (c) 2015-2016 MediaTek Inc.
> >* Author: Yong Wu 
> >*/
> > -#include 
> >   #include 
> >   #include 
> >   #include 
> > @@ -15,11 +14,13 @@
> >   #include 
> >   #include 
> >   #include 
> > +#include 
> >   #include 
> >   #include 
> >   #include 
> >   #include 
> >   #include 
> > +#include 
> >   #include 
> >   #include 
> >   #include 
> > @@ -91,6 +92,9 @@
> >   #define F_MMU_INT_ID_LARB_ID(a)   (((a) >> 7) & 0x7)
> >   #define F_MMU_INT_ID_PORT_ID(a)   (((a) >> 2) & 0x1f)
> >   
> > +#define REG_INFRA_MISC 0xf00
> > +#define F_DDR_4GB_SUPPORT_EN   BIT(13)
> > +
> 
> As this is used for infracfg, I think it would be good to add it to 
> include/linux/soc/mediatek/infracfg.h and include that file here.
Thanks for your comment.

ok. I'll do this in next version.
> 
> >   #define MTK_PROTECT_PA_ALIGN  128
> >   
> >   /*
> > @@ -599,8 +603,10 @@ static int mtk_iommu_probe(struct platform_device 
> > *pdev)
> > struct resource *res;
> > resource_size_t ioaddr;
> > struct component_match  *match = NULL;
> > +   struct regmap   *infracfg_regmap;
> 
> Maybe call it just infracfg.

ok. I'll do this in next version. 
> 
> > void*protect;
> > int i, larb_nr, ret;
> > +   u32 val;
> >   
> > data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> > if (!data)
> > @@ -614,10 +620,18 @@ static int mtk_iommu_probe(struct platform_device 
> > *pdev)
> > return -ENOMEM;
> > data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
> >   
> > -   /* Whether the current dram is over 4GB */
> > -   data->enable_4GB = !!(max_pfn > (BIT_ULL(32) >> PAGE_SHIFT));
> > -   if (!data->plat_data->has_4gb_mode)
> > +   if (data->plat_data->has_4gb_mode) {
> > +   infracfg_regmap = syscon_regmap_lookup_by_phandle(dev->of_node,
> > +   "mediatek,infracfg");
> > +   if (IS_ERR(infracfg_regmap))
> > +   return PTR_ERR(infracfg_regmap);
> 
> Do we need to error out, or could we be conservative and set endable_4GB = 
> false?

We have to error out in this case because the 4gb_mode setting must be
consistent with the h/w setting.

> 
> > +   ret = regmap_read(infracfg_regmap, REG_INFRA_MISC, );
> > +   if (ret)
> > +   return ret;
> > +   data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
> > +   } else {
> > data->enable_4GB = false;
> 
> Move that before the if() and update enable_4GB only in case of has_4gb_mode.

ok. I'll do this in next version.

Miles
> 
> > +   }
> >   
> > res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > data->base = devm_ioremap_resource(dev, res);
> > 

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Re: [PATCH 4/4] iommu/mediatek: check 4GB mode by reading infracfg

2020-07-15 Thread Matthias Brugger





On 02/07/2020 11:37, Miles Chen wrote:

In previous disscusion [1] and [2], we found that it is risky to
use max_pfn or totalram_pages to tell if 4GB mode is enabled.

Check 4GB mode by reading infracfg register, remove the usage
of the unexported symbol max_pfn.

[1] https://lkml.org/lkml/2020/6/3/733
[2] https://lkml.org/lkml/2020/6/4/136

Cc: Mike Rapoport 
Cc: David Hildenbrand 
Cc: Yong Wu 
Cc: Yingjoe Chen 
Cc: Christoph Hellwig 
Signed-off-by: Miles Chen 
---
  drivers/iommu/mtk_iommu.c | 22 ++
  1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 2be96f1cdbd2..09be57bd8d74 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -3,7 +3,6 @@
   * Copyright (c) 2015-2016 MediaTek Inc.
   * Author: Yong Wu 
   */
-#include 
  #include 
  #include 
  #include 
@@ -15,11 +14,13 @@
  #include 
  #include 
  #include 
+#include 
  #include 
  #include 
  #include 
  #include 
  #include 
+#include 
  #include 
  #include 
  #include 
@@ -91,6 +92,9 @@
  #define F_MMU_INT_ID_LARB_ID(a)   (((a) >> 7) & 0x7)
  #define F_MMU_INT_ID_PORT_ID(a)   (((a) >> 2) & 0x1f)
  
+#define REG_INFRA_MISC0xf00

+#define F_DDR_4GB_SUPPORT_EN   BIT(13)
+


As this is used for infracfg, I think it would be good to add it to 
include/linux/soc/mediatek/infracfg.h and include that file here.



  #define MTK_PROTECT_PA_ALIGN  128
  
  /*

@@ -599,8 +603,10 @@ static int mtk_iommu_probe(struct platform_device *pdev)
struct resource *res;
resource_size_t ioaddr;
struct component_match  *match = NULL;
+   struct regmap   *infracfg_regmap;


Maybe call it just infracfg.


void*protect;
int i, larb_nr, ret;
+   u32 val;
  
  	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);

if (!data)
@@ -614,10 +620,18 @@ static int mtk_iommu_probe(struct platform_device *pdev)
return -ENOMEM;
data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
  
-	/* Whether the current dram is over 4GB */

-   data->enable_4GB = !!(max_pfn > (BIT_ULL(32) >> PAGE_SHIFT));
-   if (!data->plat_data->has_4gb_mode)
+   if (data->plat_data->has_4gb_mode) {
+   infracfg_regmap = syscon_regmap_lookup_by_phandle(dev->of_node,
+   "mediatek,infracfg");
+   if (IS_ERR(infracfg_regmap))
+   return PTR_ERR(infracfg_regmap);


Do we need to error out, or could we be conservative and set endable_4GB = 
false?


+   ret = regmap_read(infracfg_regmap, REG_INFRA_MISC, );
+   if (ret)
+   return ret;
+   data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
+   } else {
data->enable_4GB = false;


Move that before the if() and update enable_4GB only in case of has_4gb_mode.


+   }
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

data->base = devm_ioremap_resource(dev, res);


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[PATCH 4/4] iommu/mediatek: check 4GB mode by reading infracfg

2020-07-02 Thread Miles Chen

In previous disscusion [1] and [2], we found that it is risky to
use max_pfn or totalram_pages to tell if 4GB mode is enabled.

Check 4GB mode by reading infracfg register, remove the usage
of the unexported symbol max_pfn.

[1] https://lkml.org/lkml/2020/6/3/733
[2] https://lkml.org/lkml/2020/6/4/136

Cc: Mike Rapoport 
Cc: David Hildenbrand 
Cc: Yong Wu 
Cc: Yingjoe Chen 
Cc: Christoph Hellwig 
Signed-off-by: Miles Chen 
---
 drivers/iommu/mtk_iommu.c | 22 ++
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 2be96f1cdbd2..09be57bd8d74 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -3,7 +3,6 @@
  * Copyright (c) 2015-2016 MediaTek Inc.
  * Author: Yong Wu 
  */
-#include 
 #include 
 #include 
 #include 
@@ -15,11 +14,13 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
@@ -91,6 +92,9 @@
 #define F_MMU_INT_ID_LARB_ID(a)(((a) >> 7) & 0x7)
 #define F_MMU_INT_ID_PORT_ID(a)(((a) >> 2) & 0x1f)
 
+#define REG_INFRA_MISC 0xf00
+#define F_DDR_4GB_SUPPORT_EN   BIT(13)
+
 #define MTK_PROTECT_PA_ALIGN   128
 
 /*
@@ -599,8 +603,10 @@ static int mtk_iommu_probe(struct platform_device *pdev)
struct resource *res;
resource_size_t ioaddr;
struct component_match  *match = NULL;
+   struct regmap   *infracfg_regmap;
void*protect;
int i, larb_nr, ret;
+   u32 val;
 
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
@@ -614,10 +620,18 @@ static int mtk_iommu_probe(struct platform_device *pdev)
return -ENOMEM;
data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
 
-   /* Whether the current dram is over 4GB */
-   data->enable_4GB = !!(max_pfn > (BIT_ULL(32) >> PAGE_SHIFT));
-   if (!data->plat_data->has_4gb_mode)
+   if (data->plat_data->has_4gb_mode) {
+   infracfg_regmap = syscon_regmap_lookup_by_phandle(dev->of_node,
+   "mediatek,infracfg");
+   if (IS_ERR(infracfg_regmap))
+   return PTR_ERR(infracfg_regmap);
+   ret = regmap_read(infracfg_regmap, REG_INFRA_MISC, );
+   if (ret)
+   return ret;
+   data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
+   } else {
data->enable_4GB = false;
+   }
 
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
data->base = devm_ioremap_resource(dev, res);
-- 
2.18.0
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Re: [PATCH 4/4] iommu/mediatek: check 4GB mode by reading infracfg

Re: [PATCH 4/4] iommu/mediatek: check 4GB mode by reading infracfg

[PATCH 4/4] iommu/mediatek: check 4GB mode by reading infracfg

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