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Message-ID: <d72b0fd9-844e-a422-45b6-261d73dbad18@aspeedtech.com>
Date:   Fri, 7 Apr 2023 10:09:24 +0800
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Subject: Re: [PATCH] drm/ast: Fix ARM compatibility
From:   Jammy Huang <jammy_huang@aspeedtech.com>
To:     <airlied@redhat.com>, <tzimmermann@suse.de>, <airlied@gmail.com>,
        <daniel@ffwll.ch>
CC:     <dri-devel@lists.freedesktop.org>, <linux-kernel@vger.kernel.org>,
        <giantl@nvidia.com>
References: <20230302021905.2777-1-jammy_huang@aspeedtech.com>
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In-Reply-To: <20230302021905.2777-1-jammy_huang@aspeedtech.com>
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Hi Thomas,

Could you help review this patch??

We met some problem on nvidia's ARM platfrom and need this patch to fix it.

On 2023/3/2 上午 10:19, Jammy Huang wrote:
> ARM architecture only has 'memory', so all devices are accessed by MMIO.
>
> Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
> ---
>   drivers/gpu/drm/ast/ast_main.c | 17 +----------------
>   1 file changed, 1 insertion(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
> index 794ffd4a29c5..f86d01e9f024 100644
> --- a/drivers/gpu/drm/ast/ast_main.c
> +++ b/drivers/gpu/drm/ast/ast_main.c
> @@ -424,22 +424,7 @@ struct ast_device *ast_device_create(const struct drm_driver *drv,
>   	if (!ast->regs)
>   		return ERR_PTR(-EIO);
>   
> -	/*
> -	 * If we don't have IO space at all, use MMIO now and
> -	 * assume the chip has MMIO enabled by default (rev 0x20
> -	 * and higher).
> -	 */
> -	if (!(pci_resource_flags(pdev, 2) & IORESOURCE_IO)) {
> -		drm_info(dev, "platform has no IO space, trying MMIO\n");
> -		ast->ioregs = ast->regs + AST_IO_MM_OFFSET;
> -	}
> -
> -	/* "map" IO regs if the above hasn't done so already */
> -	if (!ast->ioregs) {
> -		ast->ioregs = pcim_iomap(pdev, 2, 0);
> -		if (!ast->ioregs)
> -			return ERR_PTR(-EIO);
> -	}
> +	ast->ioregs = ast->regs + AST_IO_MM_OFFSET;
>   
>   	ast_detect_chip(dev, &need_post);
>   
>
> base-commit: 254986e324add8a30d0019c6da59f81adc8b565f

-- 
Best Regards
Jammy