MIPS: Fix undefined reference to physical_memsize

Since commit d41e6858ba58 ("MIPS: Kconfig: Set default MIPS system type
as generic") switched the default platform to the "generic" platform,
allmodconfig has been failing with the following linker error (among
other errors):

arch/mips/kernel/vpe-mt.o In function `vpe_run':
(.text+0x59c): undefined reference to `physical_memsize'

The Lantiq platform already worked around the same issue in commit
9050d50e2244 ("MIPS: lantiq: Set physical_memsize") by declaring
physical_memsize with the initial value of 0 (on the assumption that the
actual memory size will be hard-coded in the loaded VPE firmware), and
the Malta platform already provided physical_memsize.

Since all other platforms will fail to link with the VPE loader enabled,
only allow Lantiq and Malta platforms to enable it, by way of a
SYS_SUPPORTS_VPE_LOADER which is selected by those two platforms and
which MIPS_VPE_LOADER depends on. SYS_SUPPORTS_MULTITHREADING is now a
dependency of SYS_SUPPORTS_VPE_LOADER so that Kconfig emits a warning if
SYS_SUPPORTS_VPE_LOADER is selected without SYS_SUPPORTS_MULTITHREADING.

Fixes: d41e6858ba58 ("MIPS: Kconfig: Set default MIPS system type as generic")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Crispin <john@phrozen.org>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-mips@linux-mips.org
Tested-by: Guenter Roeck <linux@roeck-us.net>
Patchwork: https://patchwork.linux-mips.org/patch/18453/

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 659e007..8e0b370 100644 (file)
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -390,6 +390,7 @@ config LANTIQ
        select SYS_SUPPORTS_32BIT_KERNEL
        select SYS_SUPPORTS_MIPS16
        select SYS_SUPPORTS_MULTITHREADING
+       select SYS_SUPPORTS_VPE_LOADER
        select SYS_HAS_EARLY_PRINTK
        select GPIOLIB
        select SWAP_IO_SPACE
@@ -517,6 +518,7 @@ config MIPS_MALTA
        select SYS_SUPPORTS_MIPS16
        select SYS_SUPPORTS_MULTITHREADING
        select SYS_SUPPORTS_SMARTMIPS
+       select SYS_SUPPORTS_VPE_LOADER
        select SYS_SUPPORTS_ZBOOT
        select SYS_SUPPORTS_RELOCATABLE
        select USE_OF
@@ -2282,9 +2284,16 @@ config MIPSR2_TO_R6_EMULATOR
          The only reason this is a build-time option is to save ~14K from the
          final kernel image.
 
+config SYS_SUPPORTS_VPE_LOADER
+       bool
+       depends on SYS_SUPPORTS_MULTITHREADING
+       help
+         Indicates that the platform supports the VPE loader, and provides
+         physical_memsize.
+
 config MIPS_VPE_LOADER
        bool "VPE loader support."
-       depends on SYS_SUPPORTS_MULTITHREADING && MODULES
+       depends on SYS_SUPPORTS_VPE_LOADER && MODULES
        select CPU_MIPSR2_IRQ_VI
        select CPU_MIPSR2_IRQ_EI
        select MIPS_MT