In previous discussion [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 un-exported symbol max_pfn.
This is a step towards building mtk_iommu as a kernel module.
[1] https://lore.kernel.org/lkml/[email protected]/
[2] https://lore.kernel.org/lkml/[email protected]/
[3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/
Cc: Mike Rapoport <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Yong Wu <[email protected]>
Cc: Yingjoe Chen <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Matthias Brugger <[email protected]>
Signed-off-by: Miles Chen <[email protected]>
---
Change since v3
- use lore.kernel.org links
- move "change since..." after "---"
Change since v2:
- determine compatible string by m4u_plat
- rebase to next-20200720
- add "---"
Change since v1:
- remove the phandle usage, search for infracfg instead [3]
- use infracfg instead of infracfg_regmap
- move infracfg definitaions to linux/soc/mediatek/infracfg.h
- update enable_4GB only when has_4gb_mode
---
drivers/iommu/mtk_iommu.c | 34 +++++++++++++++++++++++----
include/linux/soc/mediatek/infracfg.h | 3 +++
2 files changed, 32 insertions(+), 5 deletions(-)
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 785b228d39a6..adc350150492 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 <[email protected]>
*/
-#include <linux/memblock.h>
#include <linux/bug.h>
#include <linux/clk.h>
#include <linux/component.h>
@@ -15,13 +14,16 @@
#include <linux/iommu.h>
#include <linux/iopoll.h>
#include <linux/list.h>
+#include <linux/mfd/syscon.h>
#include <linux/of_address.h>
#include <linux/of_iommu.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
+#include <linux/soc/mediatek/infracfg.h>
#include <asm/barrier.h>
#include <soc/mediatek/smi.h>
@@ -640,8 +642,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
struct resource *res;
resource_size_t ioaddr;
struct component_match *match = NULL;
+ struct regmap *infracfg;
void *protect;
int i, larb_nr, ret;
+ u32 val;
+ char *p;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
@@ -655,10 +660,29 @@ 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 (!MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE))
- data->enable_4GB = false;
+ data->enable_4GB = false;
+ if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE)) {
+ switch (data->plat_data->m4u_plat) {
+ case M4U_MT2712:
+ p = "mediatek,mt2712-infracfg";
+ break;
+ case M4U_MT8173:
+ p = "mediatek,mt8173-infracfg";
+ break;
+ default:
+ p = NULL;
+ }
+
+ infracfg = syscon_regmap_lookup_by_compatible(p);
+
+ if (IS_ERR(infracfg))
+ return PTR_ERR(infracfg);
+
+ ret = regmap_read(infracfg, REG_INFRA_MISC, &val);
+ if (ret)
+ return ret;
+ data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
+ }
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
data->base = devm_ioremap_resource(dev, res);
diff --git a/include/linux/soc/mediatek/infracfg.h b/include/linux/soc/mediatek/infracfg.h
index fd25f0148566..233463d789c6 100644
--- a/include/linux/soc/mediatek/infracfg.h
+++ b/include/linux/soc/mediatek/infracfg.h
@@ -32,6 +32,9 @@
#define MT7622_TOP_AXI_PROT_EN_WB (BIT(2) | BIT(6) | \
BIT(7) | BIT(8))
+#define REG_INFRA_MISC 0xf00
+#define F_DDR_4GB_SUPPORT_EN BIT(13)
+
int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask,
bool reg_update);
int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask,
--
2.18.0
On Wed, 2020-08-26 at 16:56 +0800, Miles Chen wrote:
> In previous discussion [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 un-exported symbol max_pfn.
>
> This is a step towards building mtk_iommu as a kernel module.
>
> [1] https://lore.kernel.org/lkml/[email protected]/
> [2] https://lore.kernel.org/lkml/[email protected]/
> [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/
>
> Cc: Mike Rapoport <[email protected]>
> Cc: David Hildenbrand <[email protected]>
> Cc: Yong Wu <[email protected]>
> Cc: Yingjoe Chen <[email protected]>
> Cc: Christoph Hellwig <[email protected]>
> Cc: Rob Herring <[email protected]>
> Cc: Matthias Brugger <[email protected]>
> Signed-off-by: Miles Chen <[email protected]>
>
> ---
>
> Change since v3
> - use lore.kernel.org links
> - move "change since..." after "---"
>
> Change since v2:
> - determine compatible string by m4u_plat
> - rebase to next-20200720
> - add "---"
>
> Change since v1:
> - remove the phandle usage, search for infracfg instead [3]
> - use infracfg instead of infracfg_regmap
> - move infracfg definitaions to linux/soc/mediatek/infracfg.h
> - update enable_4GB only when has_4gb_mode
> ---
> drivers/iommu/mtk_iommu.c | 34 +++++++++++++++++++++++----
> include/linux/soc/mediatek/infracfg.h | 3 +++
> 2 files changed, 32 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> index 785b228d39a6..adc350150492 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 <[email protected]>
> */
> -#include <linux/memblock.h>
> #include <linux/bug.h>
> #include <linux/clk.h>
> #include <linux/component.h>
> @@ -15,13 +14,16 @@
> #include <linux/iommu.h>
> #include <linux/iopoll.h>
> #include <linux/list.h>
> +#include <linux/mfd/syscon.h>
> #include <linux/of_address.h>
> #include <linux/of_iommu.h>
> #include <linux/of_irq.h>
> #include <linux/of_platform.h>
> #include <linux/platform_device.h>
> +#include <linux/regmap.h>
> #include <linux/slab.h>
> #include <linux/spinlock.h>
> +#include <linux/soc/mediatek/infracfg.h>
> #include <asm/barrier.h>
> #include <soc/mediatek/smi.h>
>
> @@ -640,8 +642,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
> struct resource *res;
> resource_size_t ioaddr;
> struct component_match *match = NULL;
> + struct regmap *infracfg;
> void *protect;
> int i, larb_nr, ret;
> + u32 val;
> + char *p;
>
> data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> if (!data)
> @@ -655,10 +660,29 @@ 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 (!MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE))
> - data->enable_4GB = false;
> + data->enable_4GB = false;
> + if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE)) {
> + switch (data->plat_data->m4u_plat) {
> + case M4U_MT2712:
> + p = "mediatek,mt2712-infracfg";
> + break;
> + case M4U_MT8173:
> + p = "mediatek,mt8173-infracfg";
> + break;
> + default:
> + p = NULL;
> + }
> +
This can be simplified:
if (data->plat_data->m4u_plat == M4U_MT2712)
p = "mediatek,mt2712-infracfg";
else if(data->plat_data->m4u_plat == M4U_MT8173)
p = "mediatek,mt8173-infracfg";
else
return -EINVAL;
Then,
Reviewed-by: Yong Wu <[email protected]>
> + infracfg = syscon_regmap_lookup_by_compatible(p);
> +
> + if (IS_ERR(infracfg))
> + return PTR_ERR(infracfg);
> +
> + ret = regmap_read(infracfg, REG_INFRA_MISC, &val);
> + if (ret)
> + return ret;
> + data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
> + }
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> data->base = devm_ioremap_resource(dev, res);
> diff --git a/include/linux/soc/mediatek/infracfg.h b/include/linux/soc/mediatek/infracfg.h
> index fd25f0148566..233463d789c6 100644
> --- a/include/linux/soc/mediatek/infracfg.h
> +++ b/include/linux/soc/mediatek/infracfg.h
> @@ -32,6 +32,9 @@
> #define MT7622_TOP_AXI_PROT_EN_WB (BIT(2) | BIT(6) | \
> BIT(7) | BIT(8))
>
> +#define REG_INFRA_MISC 0xf00
> +#define F_DDR_4GB_SUPPORT_EN BIT(13)
> +
> int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask,
> bool reg_update);
> int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask,
On 26/08/2020 10:56, Miles Chen wrote:
> In previous discussion [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 un-exported symbol max_pfn.
>
> This is a step towards building mtk_iommu as a kernel module.
>
> [1] https://lore.kernel.org/lkml/[email protected]/
> [2] https://lore.kernel.org/lkml/[email protected]/
> [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/
>
> Cc: Mike Rapoport <[email protected]>
> Cc: David Hildenbrand <[email protected]>
> Cc: Yong Wu <[email protected]>
> Cc: Yingjoe Chen <[email protected]>
> Cc: Christoph Hellwig <[email protected]>
> Cc: Rob Herring <[email protected]>
> Cc: Matthias Brugger <[email protected]>
> Signed-off-by: Miles Chen <[email protected]>
Reviewed-by: Matthias Brugger <[email protected]>
>
> ---
>
> Change since v3
> - use lore.kernel.org links
> - move "change since..." after "---"
>
> Change since v2:
> - determine compatible string by m4u_plat
> - rebase to next-20200720
> - add "---"
>
> Change since v1:
> - remove the phandle usage, search for infracfg instead [3]
> - use infracfg instead of infracfg_regmap
> - move infracfg definitaions to linux/soc/mediatek/infracfg.h
> - update enable_4GB only when has_4gb_mode
> ---
> drivers/iommu/mtk_iommu.c | 34 +++++++++++++++++++++++----
> include/linux/soc/mediatek/infracfg.h | 3 +++
> 2 files changed, 32 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> index 785b228d39a6..adc350150492 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 <[email protected]>
> */
> -#include <linux/memblock.h>
> #include <linux/bug.h>
> #include <linux/clk.h>
> #include <linux/component.h>
> @@ -15,13 +14,16 @@
> #include <linux/iommu.h>
> #include <linux/iopoll.h>
> #include <linux/list.h>
> +#include <linux/mfd/syscon.h>
> #include <linux/of_address.h>
> #include <linux/of_iommu.h>
> #include <linux/of_irq.h>
> #include <linux/of_platform.h>
> #include <linux/platform_device.h>
> +#include <linux/regmap.h>
> #include <linux/slab.h>
> #include <linux/spinlock.h>
> +#include <linux/soc/mediatek/infracfg.h>
> #include <asm/barrier.h>
> #include <soc/mediatek/smi.h>
>
> @@ -640,8 +642,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
> struct resource *res;
> resource_size_t ioaddr;
> struct component_match *match = NULL;
> + struct regmap *infracfg;
> void *protect;
> int i, larb_nr, ret;
> + u32 val;
> + char *p;
>
> data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> if (!data)
> @@ -655,10 +660,29 @@ 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 (!MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE))
> - data->enable_4GB = false;
> + data->enable_4GB = false;
> + if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE)) {
> + switch (data->plat_data->m4u_plat) {
> + case M4U_MT2712:
> + p = "mediatek,mt2712-infracfg";
> + break;
> + case M4U_MT8173:
> + p = "mediatek,mt8173-infracfg";
> + break;
> + default:
> + p = NULL;
> + }
> +
> + infracfg = syscon_regmap_lookup_by_compatible(p);
> +
> + if (IS_ERR(infracfg))
> + return PTR_ERR(infracfg);
> +
> + ret = regmap_read(infracfg, REG_INFRA_MISC, &val);
> + if (ret)
> + return ret;
> + data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
> + }
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> data->base = devm_ioremap_resource(dev, res);
> diff --git a/include/linux/soc/mediatek/infracfg.h b/include/linux/soc/mediatek/infracfg.h
> index fd25f0148566..233463d789c6 100644
> --- a/include/linux/soc/mediatek/infracfg.h
> +++ b/include/linux/soc/mediatek/infracfg.h
> @@ -32,6 +32,9 @@
> #define MT7622_TOP_AXI_PROT_EN_WB (BIT(2) | BIT(6) | \
> BIT(7) | BIT(8))
>
> +#define REG_INFRA_MISC 0xf00
> +#define F_DDR_4GB_SUPPORT_EN BIT(13)
> +
> int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask,
> bool reg_update);
> int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask,
>
On 2020-08-27 06:31, Yong Wu wrote:
> On Wed, 2020-08-26 at 16:56 +0800, Miles Chen wrote:
>> In previous discussion [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 un-exported symbol max_pfn.
>>
>> This is a step towards building mtk_iommu as a kernel module.
>>
>> [1] https://lore.kernel.org/lkml/[email protected]/
>> [2] https://lore.kernel.org/lkml/[email protected]/
>> [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/
>>
>> Cc: Mike Rapoport <[email protected]>
>> Cc: David Hildenbrand <[email protected]>
>> Cc: Yong Wu <[email protected]>
>> Cc: Yingjoe Chen <[email protected]>
>> Cc: Christoph Hellwig <[email protected]>
>> Cc: Rob Herring <[email protected]>
>> Cc: Matthias Brugger <[email protected]>
>> Signed-off-by: Miles Chen <[email protected]>
>>
>> ---
>>
>> Change since v3
>> - use lore.kernel.org links
>> - move "change since..." after "---"
>>
>> Change since v2:
>> - determine compatible string by m4u_plat
>> - rebase to next-20200720
>> - add "---"
>>
>> Change since v1:
>> - remove the phandle usage, search for infracfg instead [3]
>> - use infracfg instead of infracfg_regmap
>> - move infracfg definitaions to linux/soc/mediatek/infracfg.h
>> - update enable_4GB only when has_4gb_mode
>> ---
>> drivers/iommu/mtk_iommu.c | 34 +++++++++++++++++++++++----
>> include/linux/soc/mediatek/infracfg.h | 3 +++
>> 2 files changed, 32 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
>> index 785b228d39a6..adc350150492 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 <[email protected]>
>> */
>> -#include <linux/memblock.h>
>> #include <linux/bug.h>
>> #include <linux/clk.h>
>> #include <linux/component.h>
>> @@ -15,13 +14,16 @@
>> #include <linux/iommu.h>
>> #include <linux/iopoll.h>
>> #include <linux/list.h>
>> +#include <linux/mfd/syscon.h>
>> #include <linux/of_address.h>
>> #include <linux/of_iommu.h>
>> #include <linux/of_irq.h>
>> #include <linux/of_platform.h>
>> #include <linux/platform_device.h>
>> +#include <linux/regmap.h>
>> #include <linux/slab.h>
>> #include <linux/spinlock.h>
>> +#include <linux/soc/mediatek/infracfg.h>
>> #include <asm/barrier.h>
>> #include <soc/mediatek/smi.h>
>>
>> @@ -640,8 +642,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
>> struct resource *res;
>> resource_size_t ioaddr;
>> struct component_match *match = NULL;
>> + struct regmap *infracfg;
>> void *protect;
>> int i, larb_nr, ret;
>> + u32 val;
>> + char *p;
>>
>> data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>> if (!data)
>> @@ -655,10 +660,29 @@ 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 (!MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE))
>> - data->enable_4GB = false;
>> + data->enable_4GB = false;
Nit: this isn't really necessary, since the structure is kzalloc()ed.
>> + if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE)) {
>> + switch (data->plat_data->m4u_plat) {
>> + case M4U_MT2712:
>> + p = "mediatek,mt2712-infracfg";
>> + break;
>> + case M4U_MT8173:
>> + p = "mediatek,mt8173-infracfg";
>> + break;
>> + default:
>> + p = NULL;
>> + }
>> +
>
> This can be simplified:
>
> if (data->plat_data->m4u_plat == M4U_MT2712)
> p = "mediatek,mt2712-infracfg";
> else if(data->plat_data->m4u_plat == M4U_MT8173)
> p = "mediatek,mt8173-infracfg";
> else
> return -EINVAL;
Right, at this point the HAS_4GB_MODE flag is entirely redundant and
should be removed. FWIW I still think your suggestion of putting the
infracfg names into plat_data would be even better and cleaner - there's
plenty of precedent for that sort of thing (see "git grep '\.clk_name'"
for example).
Robin.
>
> Then,
> Reviewed-by: Yong Wu <[email protected]>
>
>
>> + infracfg = syscon_regmap_lookup_by_compatible(p);
>> +
>> + if (IS_ERR(infracfg))
>> + return PTR_ERR(infracfg);
>> +
>> + ret = regmap_read(infracfg, REG_INFRA_MISC, &val);
>> + if (ret)
>> + return ret;
>> + data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
>> + }
>>
>> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> data->base = devm_ioremap_resource(dev, res);
>> diff --git a/include/linux/soc/mediatek/infracfg.h b/include/linux/soc/mediatek/infracfg.h
>> index fd25f0148566..233463d789c6 100644
>> --- a/include/linux/soc/mediatek/infracfg.h
>> +++ b/include/linux/soc/mediatek/infracfg.h
>> @@ -32,6 +32,9 @@
>> #define MT7622_TOP_AXI_PROT_EN_WB (BIT(2) | BIT(6) | \
>> BIT(7) | BIT(8))
>>
>> +#define REG_INFRA_MISC 0xf00
>> +#define F_DDR_4GB_SUPPORT_EN BIT(13)
>> +
>> int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask,
>> bool reg_update);
>> int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask,
>
> _______________________________________________
> linux-arm-kernel mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
On Thu, 2020-08-27 at 20:27 +0100, Robin Murphy wrote:
> On 2020-08-27 06:31, Yong Wu wrote:
> > On Wed, 2020-08-26 at 16:56 +0800, Miles Chen wrote:
> >> In previous discussion [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 un-exported symbol max_pfn.
> >>
> >> This is a step towards building mtk_iommu as a kernel module.
> >>
> >> [1] https://lore.kernel.org/lkml/[email protected]/
> >> [2] https://lore.kernel.org/lkml/[email protected]/
> >> [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/
> >>
> >> Cc: Mike Rapoport <[email protected]>
> >> Cc: David Hildenbrand <[email protected]>
> >> Cc: Yong Wu <[email protected]>
> >> Cc: Yingjoe Chen <[email protected]>
> >> Cc: Christoph Hellwig <[email protected]>
> >> Cc: Rob Herring <[email protected]>
> >> Cc: Matthias Brugger <[email protected]>
> >> Signed-off-by: Miles Chen <[email protected]>
> >>
> >> ---
> >>
> >> Change since v3
> >> - use lore.kernel.org links
> >> - move "change since..." after "---"
> >>
> >> Change since v2:
> >> - determine compatible string by m4u_plat
> >> - rebase to next-20200720
> >> - add "---"
> >>
> >> Change since v1:
> >> - remove the phandle usage, search for infracfg instead [3]
> >> - use infracfg instead of infracfg_regmap
> >> - move infracfg definitaions to linux/soc/mediatek/infracfg.h
> >> - update enable_4GB only when has_4gb_mode
> >> ---
> >> drivers/iommu/mtk_iommu.c | 34 +++++++++++++++++++++++----
> >> include/linux/soc/mediatek/infracfg.h | 3 +++
> >> 2 files changed, 32 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> >> index 785b228d39a6..adc350150492 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 <[email protected]>
> >> */
> >> -#include <linux/memblock.h>
> >> #include <linux/bug.h>
> >> #include <linux/clk.h>
> >> #include <linux/component.h>
> >> @@ -15,13 +14,16 @@
> >> #include <linux/iommu.h>
> >> #include <linux/iopoll.h>
> >> #include <linux/list.h>
> >> +#include <linux/mfd/syscon.h>
> >> #include <linux/of_address.h>
> >> #include <linux/of_iommu.h>
> >> #include <linux/of_irq.h>
> >> #include <linux/of_platform.h>
> >> #include <linux/platform_device.h>
> >> +#include <linux/regmap.h>
> >> #include <linux/slab.h>
> >> #include <linux/spinlock.h>
> >> +#include <linux/soc/mediatek/infracfg.h>
> >> #include <asm/barrier.h>
> >> #include <soc/mediatek/smi.h>
> >>
> >> @@ -640,8 +642,11 @@ static int mtk_iommu_probe(struct platform_device *pdev)
> >> struct resource *res;
> >> resource_size_t ioaddr;
> >> struct component_match *match = NULL;
> >> + struct regmap *infracfg;
> >> void *protect;
> >> int i, larb_nr, ret;
> >> + u32 val;
> >> + char *p;
> >>
> >> data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> >> if (!data)
> >> @@ -655,10 +660,29 @@ 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 (!MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE))
> >> - data->enable_4GB = false;
> >> + data->enable_4GB = false;
>
> Nit: this isn't really necessary, since the structure is kzalloc()ed.
Thanks for the comment, I will remove this this in v5.
>
> >> + if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE)) {
> >> + switch (data->plat_data->m4u_plat) {
> >> + case M4U_MT2712:
> >> + p = "mediatek,mt2712-infracfg";
> >> + break;
> >> + case M4U_MT8173:
> >> + p = "mediatek,mt8173-infracfg";
> >> + break;
> >> + default:
> >> + p = NULL;
> >> + }
> >> +
> >
> > This can be simplified:
> >
> > if (data->plat_data->m4u_plat == M4U_MT2712)
> > p = "mediatek,mt2712-infracfg";
> > else if(data->plat_data->m4u_plat == M4U_MT8173)
> > p = "mediatek,mt8173-infracfg";
> > else
> > return -EINVAL;
>
> Right, at this point the HAS_4GB_MODE flag is entirely redundant and
> should be removed. FWIW I still think your suggestion of putting the
> infracfg names into plat_data would be even better and cleaner - there's
> plenty of precedent for that sort of thing (see "git grep '\.clk_name'"
> for example).
>
> Robin.
hmm, I have no strong opinion about this. We have discussed this
approach before and built this patch based on the discussion.
https://lore.kernel.org/patchwork/patch/1276801/
Miles
>
> >
> > Then,
> > Reviewed-by: Yong Wu <[email protected]>
> >
> >
> >> + infracfg = syscon_regmap_lookup_by_compatible(p);
> >> +
> >> + if (IS_ERR(infracfg))
> >> + return PTR_ERR(infracfg);
> >> +
> >> + ret = regmap_read(infracfg, REG_INFRA_MISC, &val);
> >> + if (ret)
> >> + return ret;
> >> + data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
> >> + }
> >>
> >> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >> data->base = devm_ioremap_resource(dev, res);
> >> diff --git a/include/linux/soc/mediatek/infracfg.h b/include/linux/soc/mediatek/infracfg.h
> >> index fd25f0148566..233463d789c6 100644
> >> --- a/include/linux/soc/mediatek/infracfg.h
> >> +++ b/include/linux/soc/mediatek/infracfg.h
> >> @@ -32,6 +32,9 @@
> >> #define MT7622_TOP_AXI_PROT_EN_WB (BIT(2) | BIT(6) | \
> >> BIT(7) | BIT(8))
> >>
> >> +#define REG_INFRA_MISC 0xf00
> >> +#define F_DDR_4GB_SUPPORT_EN BIT(13)
> >> +
> >> int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask,
> >> bool reg_update);
> >> int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask,
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > [email protected]
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> >