On Wed, Dec 08, 2021 at 05:27:19PM +0800, Tiezhu Yang wrote:
> After commit 9f76779f2418 ("MIPS: implement architecture-specific
> 'pci_remap_iospace()'"), there exists the following warning on the
> Loongson64 platform:
>
> loongson-pci 1a000000.pci: IO 0x0018020000..0x001803ffff -> 0x0000020000
> loongson-pci 1a000000.pci: MEM 0x0040000000..0x007fffffff -> 0x0040000000
> ------------[ cut here ]------------
> WARNING: CPU: 2 PID: 1 at arch/mips/pci/pci-generic.c:55 pci_remap_iospace+0x84/0x90
> resource start address is not zero
> ...
> Call Trace:
> [<ffffffff8020dc78>] show_stack+0x40/0x120
> [<ffffffff80cf4a0c>] dump_stack_lvl+0x58/0x74
> [<ffffffff8023a0b0>] __warn+0xe0/0x110
> [<ffffffff80cee02c>] warn_slowpath_fmt+0xa4/0xd0
> [<ffffffff80cecf24>] pci_remap_iospace+0x84/0x90
> [<ffffffff807f9864>] devm_pci_remap_iospace+0x5c/0xb8
> [<ffffffff808121b0>] devm_of_pci_bridge_init+0x178/0x1f8
> [<ffffffff807f4000>] devm_pci_alloc_host_bridge+0x78/0x98
> [<ffffffff80819454>] loongson_pci_probe+0x34/0x160
> [<ffffffff809203cc>] platform_probe+0x6c/0xe0
> [<ffffffff8091d5d4>] really_probe+0xbc/0x340
> [<ffffffff8091d8f0>] __driver_probe_device+0x98/0x110
> [<ffffffff8091d9b8>] driver_probe_device+0x50/0x118
> [<ffffffff8091dea0>] __driver_attach+0x80/0x118
> [<ffffffff8091b280>] bus_for_each_dev+0x80/0xc8
> [<ffffffff8091c6d8>] bus_add_driver+0x130/0x210
> [<ffffffff8091ead4>] driver_register+0x8c/0x150
> [<ffffffff80200a8c>] do_one_initcall+0x54/0x288
> [<ffffffff811a5320>] kernel_init_freeable+0x27c/0x2e4
> [<ffffffff80cfc380>] kernel_init+0x2c/0x134
> [<ffffffff80205a2c>] ret_from_kernel_thread+0x14/0x1c
> ---[ end trace e4a0efe10aa5cce6 ]---
> loongson-pci 1a000000.pci: error -19: failed to map resource [io 0x20000-0x3ffff]
>
> We can see that the resource start address is 0x0000020000, because
> the ISA Bridge used the zero address which is defined in the dts file
> arch/mips/boot/dts/loongson/ls7a-pch.dtsi:
>
> ISA Bridge: /bus@10000000/isa@18000000
> IO 0x0000000018000000..0x000000001801ffff -> 0x0000000000000000
>
> Based on the above analysis, the architecture-specific pci_remap_iospace()
> is not suitable for Loongson64, we should only define pci_remap_iospace()
> for Ralink on MIPS based on the commit background.
>
> Suggested-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
> ---
> arch/mips/include/asm/mach-ralink/spaces.h | 2 ++
> arch/mips/include/asm/pci.h | 4 ----
> arch/mips/pci/pci-generic.c | 2 ++
> 3 files changed, 4 insertions(+), 4 deletions(-)
applied to mips-fixes.
Thomas.
--
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