From c2c59456e1fcad3f464761c5839399176e3a934a Mon Sep 17 00:00:00 2001 From: Miles Chen Date: Fri, 4 Sep 2020 18:40:38 +0800 Subject: iommu/mediatek: Check 4GB mode by reading infracfg 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.chen@mediatek.com/ [2] https://lore.kernel.org/lkml/20200604080120.2628-1-miles.chen@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 Cc: Joerg Roedel Reviewed-by: Matthias Brugger Signed-off-by: Miles Chen Link: https://lore.kernel.org/r/20200904104038.4979-1-miles.chen@mediatek.com Signed-off-by: Joerg Roedel --- include/linux/soc/mediatek/infracfg.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/soc') 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, -- cgit v1.3-18-gd494