Re: [RESEND PATCH v4] iommu/mediatek: check 4GB mode by reading infracfg
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/20200603161132.2441-1-miles.c...@mediatek.com/ > >> [2] > >> https://lore.kernel.org/lkml/20200604080120.2628-1-miles.c...@mediatek.com/ > >> [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/ > >> > >> Cc: Mike Rapoport > >> Cc: David Hildenbrand > >> Cc: Yong Wu > >> Cc: Yingjoe Chen > >> Cc: Christoph Hellwig > >> Cc: Rob Herring > >> Cc: Matthias Brugger > >> Signed-off-by: Miles Chen > >> > >> --- > >> > >> 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 > >>*/ > >> -#include > >> #include > >> #include > >> #include > >> @@ -15,13 +14,16 @@ > >> #include > >> #include > >> #include > >> +#include > >> #include > >> #include > >> #include > >> #include > >> #include > >> +#include > >> #include > >> #include > >> +#include > >> #include > >> #include > >> > >> @@ -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 > > > > > >> + 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; > >>
Re: [RESEND PATCH v4] iommu/mediatek: check 4GB mode by reading infracfg
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/20200603161132.2441-1-miles.c...@mediatek.com/ [2] https://lore.kernel.org/lkml/20200604080120.2628-1-miles.c...@mediatek.com/ [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/ Cc: Mike Rapoport Cc: David Hildenbrand Cc: Yong Wu Cc: Yingjoe Chen Cc: Christoph Hellwig Cc: Rob Herring Cc: Matthias Brugger Signed-off-by: Miles Chen --- 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 */ -#include #include #include #include @@ -15,13 +14,16 @@ #include #include #include +#include #include #include #include #include #include +#include #include #include +#include #include #include @@ -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 + 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_MISC0xf00 +#define F_DDR_4GB_SUPPORT_EN BIT(13) + int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask, bool reg_update);
Re: [RESEND PATCH v4] iommu/mediatek: check 4GB mode by reading infracfg
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/20200603161132.2441-1-miles.c...@mediatek.com/ [2] https://lore.kernel.org/lkml/20200604080120.2628-1-miles.c...@mediatek.com/ [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/ Cc: Mike Rapoport Cc: David Hildenbrand Cc: Yong Wu Cc: Yingjoe Chen Cc: Christoph Hellwig Cc: Rob Herring Cc: Matthias Brugger Signed-off-by: Miles Chen Reviewed-by: Matthias Brugger --- 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 */ -#include #include #include #include @@ -15,13 +14,16 @@ #include #include #include +#include #include #include #include #include #include +#include #include #include +#include #include #include @@ -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_MISC0xf00 +#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,
Re: [RESEND PATCH v4] iommu/mediatek: check 4GB mode by reading infracfg
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/20200603161132.2441-1-miles.c...@mediatek.com/ > [2] > https://lore.kernel.org/lkml/20200604080120.2628-1-miles.c...@mediatek.com/ > [3] https://lore.kernel.org/lkml/20200715205120.GA778876@bogus/ > > Cc: Mike Rapoport > Cc: David Hildenbrand > Cc: Yong Wu > Cc: Yingjoe Chen > Cc: Christoph Hellwig > Cc: Rob Herring > Cc: Matthias Brugger > Signed-off-by: Miles Chen > > --- > > 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 > */ > -#include > #include > #include > #include > @@ -15,13 +14,16 @@ > #include > #include > #include > +#include > #include > #include > #include > #include > #include > +#include > #include > #include > +#include > #include > #include > > @@ -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 > + 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,