diff options
| author | Miles Chen <miles.chen@mediatek.com> | 2020-09-04 13:40:38 +0300 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-09-04 14:20:36 +0300 |
| commit | c2c59456e1fcad3f464761c5839399176e3a934a (patch) | |
| tree | e5c2e6e114d5b4195f518e9251b7ede6344e8caf /drivers/iommu/mtk_iommu.c | |
| parent | f53dd97874e6d916ce7d3a487a1073ef5c10e153 (diff) | |
| download | linux-c2c59456e1fcad3f464761c5839399176e3a934a.tar.xz | |
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 <rppt@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yong Wu <yong.wu@mediatek.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Rob Herring <robh@kernel.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Joerg Roedel <joro@8bytes.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Link: https://lore.kernel.org/r/20200904104038.4979-1-miles.chen@mediatek.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/mtk_iommu.c')
| -rw-r--r-- | drivers/iommu/mtk_iommu.c | 33 |
1 files changed, 28 insertions, 5 deletions
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index b99c2b4b48ca..94f676659ed5 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 <yong.wu@mediatek.com> */ -#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 +660,28 @@ 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; + 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); |