| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <1598506280.19851.5.camel@mhfsdcap03>
Date: Thu, 27 Aug 2020 13:31:20 +0800
From: Yong Wu <yong.wu@...iatek.com>
To: Miles Chen <miles.chen@...iatek.com>
CC: Joerg Roedel <joro@...tes.org>,
Matthias Brugger <matthias.bgg@...il.com>,
Rob Herring <robh@...nel.org>,
<iommu@...ts.linux-foundation.org>,
<linux-arm-kernel@...ts.infradead.org>,
<linux-mediatek@...ts.infradead.org>,
<linux-kernel@...r.kernel.org>, <wsd_upstream@...iatek.com>,
Mike Rapoport <rppt@...ux.ibm.com>,
"David Hildenbrand" <david@...hat.com>,
Yingjoe Chen <yingjoe.chen@...iatek.com>,
Christoph Hellwig <hch@....de>
Subject: 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.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@...ux.ibm.com>
> Cc: David Hildenbrand <david@...hat.com>
> Cc: Yong Wu <yong.wu@...iatek.com>
> Cc: Yingjoe Chen <yingjoe.chen@...iatek.com>
> Cc: Christoph Hellwig <hch@....de>
> Cc: Rob Herring <robh@...nel.org>
> Cc: Matthias Brugger <matthias.bgg@...il.com>
> Signed-off-by: Miles Chen <miles.chen@...iatek.com>
>
> ---
>
> 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 <yong.wu@...iatek.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 +660,29 @@ 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 <yong.wu@...iatek.com>
> + 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,
Powered by blists - more mailing lists