[PATCH] MIPS: RALINK: Define pci_remap_iospace under CONFIG_PCI_DRIVERS_GENERIC

From: Tiezhu Yang
Date: Wed May 25 2022 - 07:30:14 EST


kernel test robot reports a build error used with clang compiler and
mips-randconfig [1]:

ld.lld: error: undefined symbol: pci_remap_iospace

we can see the following configs in the mips-randconfig file:

CONFIG_RALINK=y
CONFIG_SOC_MT7620=y
CONFIG_PCI_DRIVERS_LEGACY=y
CONFIG_PCI=y

CONFIG_RALINK is set, so pci_remap_iospace is defined in the related
arch/mips/include/asm/mach-ralink/spaces.h header file:

#define pci_remap_iospace pci_remap_iospace

CONFIG_PCI is set, so pci_remap_iospace() in drivers/pci/pci.c is not
built due to pci_remap_iospace is defined under CONFIG_RALINK.

#ifndef pci_remap_iospace
int pci_remap_iospace(const struct resource *res, ...)

$ objdump -d drivers/pci/pci.o | grep pci_remap_iospace
00004cc8 <devm_pci_remap_iospace>:
4d18: 10400008 beqz v0,4d3c <devm_pci_remap_iospace+0x74>
4d2c: 1040000c beqz v0,4d60 <devm_pci_remap_iospace+0x98>
4d70: 1000fff3 b 4d40 <devm_pci_remap_iospace+0x78>

In addition, CONFIG_PCI_DRIVERS_GENERIC is not set, so pci_remap_iospace()
in arch/mips/pci/pci-generic.c is not built too.

#ifdef pci_remap_iospace
int pci_remap_iospace(const struct resource *res, ...)

For the above reasons, undefined reference pci_remap_iospace() looks like
reasonable.

Here are simple steps to reproduce used with gcc and defconfig:

cd mips.git
make vocore2_defconfig # set RALINK, SOC_MT7620, PCI_DRIVERS_LEGACY
make menuconfig # set PCI
make

there exists the following build error:

LD vmlinux.o
MODPOST vmlinux.symvers
MODINFO modules.builtin.modinfo
GEN modules.builtin
LD .tmp_vmlinux.kallsyms1
drivers/pci/pci.o: In function `devm_pci_remap_iospace':
pci.c:(.text+0x4d24): undefined reference to `pci_remap_iospace'
Makefile:1158: recipe for target 'vmlinux' failed
make: *** [vmlinux] Error 1

Define pci_remap_iospace under CONFIG_PCI_DRIVERS_GENERIC can fix the build
error, with this patch, no build error remains. This patch is similar with
commit e538e8649892 ("MIPS: asm: pci: define arch-specific
'pci_remap_iospace()' dependent on 'CONFIG_PCI_DRIVERS_GENERIC'").

[1] https://lore.kernel.org/lkml/202205251247.nQ5cxSV6-lkp@xxxxxxxxx/

Fixes: 09d97da660ff ("MIPS: Only define pci_remap_iospace() for Ralink")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
arch/mips/include/asm/mach-ralink/spaces.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/mips/include/asm/mach-ralink/spaces.h b/arch/mips/include/asm/mach-ralink/spaces.h
index f7af11e..a9f0570 100644
--- a/arch/mips/include/asm/mach-ralink/spaces.h
+++ b/arch/mips/include/asm/mach-ralink/spaces.h
@@ -6,7 +6,9 @@
#define PCI_IOSIZE SZ_64K
#define IO_SPACE_LIMIT (PCI_IOSIZE - 1)

+#ifdef CONFIG_PCI_DRIVERS_GENERIC
#define pci_remap_iospace pci_remap_iospace
+#endif

#include <asm/mach-generic/spaces.h>
#endif
--
2.1.0