From: "Christian König" <christian.koenig@amd.com>
To: He Ying <heying24@huawei.com>,
alexander.deucher@amd.com, Xinhui.Pan@amd.com, airlied@linux.ie,
daniel@ffwll.ch, airlied@redhat.com, bskeggs@redhat.com,
matthew.auld@intel.com, Ramesh.Errabolu@amd.com,
mchehab+huawei@kernel.org, Dennis.Li@amd.com,
funfunctor@folklore1984.net
Cc: amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH -next] drm/amdgpu: Use DIV_ROUND_UP_ULL instead of DIV_ROUND_UP
Date: Thu, 10 Jun 2021 10:20:44 +0200 [thread overview]
Message-ID: <5ffe00de-a7b6-3ac4-f61a-5f28b653e7b1@amd.com> (raw)
In-Reply-To: <20210610082005.86876-1-heying24@huawei.com>
Am 10.06.21 um 10:20 schrieb He Ying:
> When compiling the kernel for MIPS with CONFIG_DRM_AMDGPU = y, errors are
> encountered as follows:
>
> drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.o: In function `amdgpu_vram_mgr_new':
> amdgpu_vram_mgr.c:(.text+0x740): undefined reference to `__udivdi3'
>
> Making a 64 bit division by a/b (a is uint64_t) is not supported by default
> in linux kernel space. Instead, using do_div is OK for this situation. For
> this problem, using DIV_ROUND_UP_ULL instead of DIV_ROUND_UP is better.
Already fixed by this patch in drm-next:
commit 691cf8cd7a531dbfcc29d09a23c509a86fd9b24f
Author: Dave Airlie <airlied@redhat.com>
Date: Thu Jun 10 12:59:00 2021 +1000
drm/amdgpu: use correct rounding macro for 64-bit
This fixes 32-bit arm build due to lack of 64-bit divides.
Regards,
Christian.
>
> Fixes: 6a7f76e70fac ("drm/amdgpu: add VRAM manager v2")
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Signed-off-by: He Ying <heying24@huawei.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
> index 9a6df02477ce..436ec246a7da 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c
> @@ -407,7 +407,7 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man,
> #endif
> pages_per_node = max_t(uint32_t, pages_per_node,
> tbo->page_alignment);
> - num_nodes = DIV_ROUND_UP(PFN_UP(mem_bytes), pages_per_node);
> + num_nodes = DIV_ROUND_UP_ULL(PFN_UP(mem_bytes), pages_per_node);
> }
>
> node = kvmalloc(struct_size(node, mm_nodes, num_nodes),
next prev parent reply other threads:[~2021-06-10 8:20 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-10 8:20 [PATCH -next] drm/amdgpu: Use DIV_ROUND_UP_ULL instead of DIV_ROUND_UP He Ying
2021-06-10 8:20 ` Christian König [this message]
2021-06-10 8:41 ` He Ying
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5ffe00de-a7b6-3ac4-f61a-5f28b653e7b1@amd.com \
--to=christian.koenig@amd.com \
--cc=Dennis.Li@amd.com \
--cc=Ramesh.Errabolu@amd.com \
--cc=Xinhui.Pan@amd.com \
--cc=airlied@linux.ie \
--cc=airlied@redhat.com \
--cc=alexander.deucher@amd.com \
--cc=amd-gfx@lists.freedesktop.org \
--cc=bskeggs@redhat.com \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=funfunctor@folklore1984.net \
--cc=heying24@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=matthew.auld@intel.com \
--cc=mchehab+huawei@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).