Re: [PATCH] soc: kunpeng_hccs: fix some sparse warnings about incorrect type

From: Arnd Bergmann
Date: Thu Aug 17 2023 - 07:55:29 EST


On Thu, Aug 17, 2023, at 03:37, lihuisong (C) wrote:
> 在 2023/8/16 21:17, Arnd Bergmann 写道:
>> On Tue, Aug 15, 2023, at 14:52, Huisong Li wrote:
>>> @@ -199,8 +200,8 @@ static int hccs_pcc_cmd_send(struct hccs_dev *hdev, u8 cmd,
>>> struct hccs_desc *desc)
>>> {
>>> struct hccs_mbox_client_info *cl_info = &hdev->cl_info;
>>> - struct acpi_pcct_shared_memory *comm_base = cl_info->pcc_comm_addr;
>>> - void *comm_space = (void *)(comm_base + 1);
>>> + void __iomem *comm_space = (u8 *)cl_info->pcc_comm_addr +
>>> + sizeof(struct acpi_pcct_shared_memory);
>>> struct hccs_fw_inner_head *fw_inner_head;
>>> struct acpi_pcct_shared_memory tmp = {0};
>>> u16 comm_space_size;
>> The cast still looks wrong, while both comm_space and ->pcc_comm_addr
>> are __iomem pointers, casting to a non-__iomem u8 pointer should
>> still produce that warning. I'd suggest casting to (u8 __iomem *)
>> or (void __iomem *), I assume you still need a cast here to get
>> the correct address.
> Thanks Arnd.
>
> You are right. So I modify it by dropping (u8 *) here in patch v2.
> Please take a look at this again.

Right, if pcc_comm_addr is already a u8 __iomem* or void*, that
works, I though the cast was needed since it points to a larger
object, which would throw off the calculation.

> If it is ok for you, can you apply this patch to soc/soc.git?

Yes, of course.

Arnd