Subject: Re: [PATCH] iommu/rockchip: Fix PAGE_DESC_HI_MASKs for RK3568
To:     Alex Bee <knaerzche@gmail.com>, Joerg Roedel <joro@8bytes.org>,
        Will Deacon <will@kernel.org>, Heiko Stuebner <heiko@sntech.de>
Cc:     iommu@lists.linux-foundation.org,
        linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20211124021325.858139-1-knaerzche@gmail.com>
From:   Benjamin Gaignard <benjamin.gaignard@collabora.com>
Message-ID: <ce137254-eee4-3241-a977-84cccb44b7cd@collabora.com>
Date:   Wed, 24 Nov 2021 09:25:34 +0100
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Le 24/11/2021 à 03:13, Alex Bee a écrit :
> With the submission of iommu driver for RK3568 a subtle bug was
> introduced: PAGE_DESC_HI_MASK1 and PAGE_DESC_HI_MASK2 have to be
> the other way arround - that leads to random errors, especially when
> addresses beyond 32 bit are used.
>
> Fix it.
>
> Fixes: c55356c534aa ("iommu: rockchip: Add support for iommu v2")
> Signed-off-by: Alex Bee <knaerzche@gmail.com>

Thanks for the fix.

Reviewed-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>

> ---
>
> I've found this bug, when testing the recent VOP2 submission, which is
> the first perpherial which uses iommu for RK356x. I could use it on my
> quartz64 8GB board only, when limiting the available memory to less 4GB.
>
> This patch fixes it.
>
>   drivers/iommu/rockchip-iommu.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
> index 5cb260820eda..7f23ad61c094 100644
> --- a/drivers/iommu/rockchip-iommu.c
> +++ b/drivers/iommu/rockchip-iommu.c
> @@ -200,8 +200,8 @@ static inline phys_addr_t rk_dte_pt_address(u32 dte)
>   #define DTE_HI_MASK2	GENMASK(7, 4)
>   #define DTE_HI_SHIFT1	24 /* shift bit 8 to bit 32 */
>   #define DTE_HI_SHIFT2	32 /* shift bit 4 to bit 36 */
> -#define PAGE_DESC_HI_MASK1	GENMASK_ULL(39, 36)
> -#define PAGE_DESC_HI_MASK2	GENMASK_ULL(35, 32)
> +#define PAGE_DESC_HI_MASK1	GENMASK_ULL(35, 32)
> +#define PAGE_DESC_HI_MASK2	GENMASK_ULL(39, 36)
>   
>   static inline phys_addr_t rk_dte_pt_address_v2(u32 dte)
>   {