Re: [PATCH v3 5/6] MIPS: implement architecture-specific 'pci_remap_iospace()'
From: Jiaxun Yang
Date: Thu Dec 16 2021 - 08:08:09 EST
在2021年12月16日十二月 上午11:44,Xi Ruoyao写道:
> On Sat, 2021-09-25 at 22:32 +0200, Sergio Paracuellos wrote:
>> To make PCI IO work we need to properly virtually map IO cpu physical address
>> and set this virtual address as the address of the first PCI IO port which
>> is set using function 'set_io_port_base()'.
>>
>> Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
>> Signed-off-by: Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx>
>
> Hi,
>
> the change is causing a WARNING on loongson64g-4core-ls7a:
>
> [ 0.105781] loongson-pci 1a000000.pci: IO
> 0x0018020000..0x001803ffff ->
> 0x0000020000
> [ 0.105792] loongson-pci 1a000000.pci: MEM
> 0x0040000000..0x007fffffff ->
> 0x0040000000
> [ 0.105801] ------------[ cut here ]------------
> [ 0.105804] WARNING: CPU: 0 PID: 1 at arch/mips/pci/pci-generic.c:55
> pci_remap_iospace+0x80/0x88
> [ 0.105815] resource start address is not zero
>
> I'm not sure how to fix this one.
>
>> ---
>> arch/mips/include/asm/pci.h | 2 ++
>> arch/mips/pci/pci-generic.c | 14 ++++++++++++++
>> 2 files changed, 16 insertions(+)
>>
>> diff --git a/arch/mips/include/asm/pci.h b/arch/mips/include/asm/pci.h
>> index 9ffc8192adae..35270984a5f0 100644
>> --- a/arch/mips/include/asm/pci.h
>> +++ b/arch/mips/include/asm/pci.h
>> @@ -20,6 +20,8 @@
>> #include <linux/list.h>
>> #include <linux/of.h>
>>
>> +#define pci_remap_iospace pci_remap_iospace
>> +
>> #ifdef CONFIG_PCI_DRIVERS_LEGACY
>>
>> /*
>> diff --git a/arch/mips/pci/pci-generic.c b/arch/mips/pci/pci-generic.c
>> index 95b00017886c..18eb8a453a86 100644
>> --- a/arch/mips/pci/pci-generic.c
>> +++ b/arch/mips/pci/pci-generic.c
>> @@ -46,3 +46,17 @@ void pcibios_fixup_bus(struct pci_bus *bus)
>> {
>> pci_read_bridge_bases(bus);
>> }
>> +
>> +int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
>> +{
>> + unsigned long vaddr;
>> +
>> + if (res->start != 0) {
>> + WARN_ONCE(1, "resource start address is not zero\n");
>> + return -ENODEV;
>> + }
>> +
>> + vaddr = (unsigned long)ioremap(phys_addr, resource_size(res));
>> + set_io_port_base(vaddr);
>> + return 0;
>> +}
Hi all,
Another way could be keeping a linked list about PIO->PHYS mapping instead of using the single io_port_base variable.
Thanks.
>
> --
> Xi Ruoyao <xry111@xxxxxxxxxxxxxxxx>
> School of Aerospace Science and Technology, Xidian University
--
- Jiaxun